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Sample records for platelet distribution width

  1. Association of Adiposity Indices with Platelet Distribution Width and Mean Platelet Volume in Chinese Adults.

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    Jian Hou

    Full Text Available Hypoxia is a prominent characteristic of inflammatory tissue lesions. It can affect platelet function. While mean platelet volume (MPV and platelet distribution width (PDW are sample platelet indices, they may reflect subcinical platelet activation. To investigated associations between adiposity indices and platelet indices, 17327 eligible individuals (7677 males and 9650 females from the Dongfeng-Tongji Cohort Study (DFTJ-Cohort Study, n=27009 were included in this study, except for 9682 individuals with missing data on demographical, lifestyle, physical indicators and diseases relative to PDW and MPV. Associations between adiposity indices including waist circumstance (WC, waist-to-height ratio (WHtR, body mass index (BMI, and MPV or PDW in the participants were analyzed using multiple logistic regressions. There were significantly negative associations between abnormal PDW and WC or WHtR for both sexes (ptrend<0.001 for all, as well as abnormal MPV and WC or WHtR among female participants (ptrend<0.05 for all. In the highest BMI groups, only females with low MPV or PDW were at greater risk for having low MPV (OR=1.33, 95% CI=1.10, 1.62 ptrend<0.001 or PDW (OR=1.34, 95% CI=1.14, 1.58, ptrend<0.001 than those who had low MPV or PDW in the corresponding lowest BMI group. The change of PDW seems more sensitive than MPV to oxidative stress and hypoxia. Associations between reduced PDW and MPV values and WC, WHtR and BMI values in Chinese female adults may help us to further investigate early changes in human body.

  2. Mean platelet volume and red cell distribution width levels in initial evaluation of panic disorder

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    Asoglu M

    2016-09-01

    Full Text Available Mehmet Asoglu,1 Mehmet Aslan,2 Okan Imre,1 Yuksel Kivrak,3 Oznur Akil,1 Emin Savik,4 Hasan Buyukaslan,5 Ulker Fedai,1 Abdurrahman Altındag6 1Department of Psychiatry, Faculty of Medicine, Harran University, Sanliurfa, 2Department of Internal Medicine, Faculty of Medicine, Yuzuncu Yil University, Van, 3Department of Psychiatry, Faculty of Medicine, Kafkas University, Kars, 4Department of Clinical Biochemistry, Faculty of Medicine, Harran University, 5Department of Emergency Medicine, Faculty of Medicine, Harran University, Sanliurfa, 6Department of Psychiatry, Faculty of Medicine, Gaziantep University, Gaziantep, Turkey Background: As the relationship between psychological stress and platelet activation has been widely studied in recent years, activated platelets lead to certain biochemical changes, which occur in the brain in patients with mental disorders. However, data relating to the mean platelet volume (MPV in patients with panic disorder (PD are both limited and controversial. Herein, we aimed to evaluate, for the first time, the red cell distribution width (RDW levels combined with MPV levels in patients with PD.Patients and methods: Between January 2012 and June 2015, data of 30 treatment-naïve patients (16 females, 14 males; mean age: 37±10 years; range: 18–59 years who were diagnosed with PD and 25 age- and sex-matched healthy volunteers (10 females, 15 males; mean age: 36±13 years; range: 18–59 years (control group were retrospectively analyzed. The white blood cell count (WBC, MPV, and RDW levels were measured in both groups.Results: The mean WBC, MPV, and RDW levels were 9,173.03±2,400.31/mm3, 8.19±1.13 fl, and 12.47±1.14%, respectively, in the PD group. These values were found to be 7,090.24±1,032.61, 6.85±0.67, and 11.63±0.85, respectively, in the healthy controls. The WBC, MPV, and RDW levels were significantly higher in the patients with PD compared to the healthy controls (P=0.001, P=0.001, and P=0

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

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    Giuseppe Lippi

    2014-01-01

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

  4. Red cell distribution width and mean platelet volume in patients with irritable bowel syndrome

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    Alcelik, Aytekin; Tekce, Buket Kin; Tekelioglu, Vildan; Sit, Mustafa; Savli, Haluk

    2014-01-01

    Introduction Possible pathophysiological mechanisms of irritable bowel syndrome (IBS) are interactions between microbial flora of the gut and the mucosal/systemic immune system, post-infectious status and inflammation. Mean platelet volume (MPV) and red cell distribution width (RDW) have been reported as inflammatory markers in patients with inflammatory bowel disease, but they have not been studied in functional gastrointestinal disorders. Aim To investigate whether there was an association between haemogram parameters (RDW and MPV) and IBS. Material and methods Forty patients with IBS and 44 healthy controls were included to this retrospective study. Patients diagnosed with IBS according to Rome III criteria were included as the IBS group. They were all screened for psychiatric or organic bowel diseases for the sake of precise diagnosis. Results Both RDW (p < 0.001) and MPV (p = 0.046) were increased in patients with IBS compared to controls. This increase in RDW and MPV was independent of the type of IBS. Conclusions The RDW and MPV should be laboratory indicators of IBS. More prospective studies with larger cohorts are needed to confirm our results. PMID:25097713

  5. The effect of erythropoietin on platelet distribution width during ischemia reperfusion injury in rats

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    Constantinos Tsompos

    2014-04-01

    Full Text Available OBJECTIVE: Aim of this experiment study was the erythropoietin (Epo testing, on rat model and particularly on ischemia reperfusion protocol. The benefit or the non effect of that molecule was studied hematologically on platelet distribution width (PDW. METHODS: 40 rats were used of mean weight 247,7 gr. PDW was measured on these time points: on 60 min after reperfusion (groups A and C, and on 120 min after reperfusion (groups B and D, A and B without but C and D with Epo administration. RESULTS: Epo administration increased significantly the PDW levels by 0.22 % [0.034374 % - 0.4056259 %] (P= 0.0214, in accordance also with paired t-test (P= 0.0196, 2 reperfusion time decreased significantly the PDW levels by 0.27 % [-0.4483669 % - 0.0916332 %] (P= 0.0040, in accordance also with paired t-test (P= 0.0012, and 3 interaction of Epo administration and reperfusion time increased non significantly the PDW levels by 0.06 % [-0.054648 % - 0.1819207 %] (P= 0.0615. CONCLUSION: Epo administration has significant increasing short-term effects on PDW levels. However, reperfusion time attenuates significantly this effect. Their interaction seems to resemble the action of Epo administration. The following question is whether these PDW levels alterations are the cause or the result of diseases process modification.

  6. Aspirin resistance may be identified by miR-92a in plasma combined with platelet distribution width

    DEFF Research Database (Denmark)

    Binderup, Helle Glud; Houlind, Kim; Madsen, Jonna Skov;

    2016-01-01

    OBJECTIVE: Aspirin is a widely used drug for prevention of thrombotic events in cardiovascular patients, but approximately 25% of patients experience insufficient platelet inhibition due to aspirin, and remain in risk of cardiovascular events. This study aimed to investigate the value...... of circulating miR-92a and platelet size as biomarkers of the individual response to aspirin therapy. METHODS: Blood samples were collected from 50 healthy blood donors without antithrombotic medication and 50 patients with intermittent claudication on daily aspirin therapy. Based on results from the arachidonic...... acid stimulated aggregation test on Multiplate®analyzer (ASPItest), patients were defined as aspirin resistant (n=10) or aspirin responders (n=40). Plasma levels of miR-92a were evaluated by RT-qPCR analysis and platelet distribution width (PDW) was used to assess platelet size variability. Receiver...

  7. Study on the relationship between mean platelet volume and platelet distribution width with coronary artery lesion in children with Kawasaki disease.

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    Liu, Ruixi; Gao, Fang; Huo, Junming; Yi, Qijian

    2012-01-01

    Mean platelet volume (MPV) and platelet distribution width (PDW) are correlated with platelet function and may be a more sensitive index than platelet number as a marker of clinical interest in various disorders. Therefore, this study was designed to answer the following questions: do MPV and PDW levels change in Kawasaki disease (KD), is there any relation between CAL in children with MPV and PDW and whether MPV and PDW might support a diagnosis of incomplete KD. A total of 309 KD patients and 160 sex-age matched healthy subjects were enrolled into the study. For all subjects following tests were performed: MPV, PDW, platelet count, white blood cells counts (WBC), C reactive protein (CRP) and erythrocyte sedimentation rate (ESR). Patients with CALs were assigned to three groups depending on the extent of CALs which were visualized by echocardiography: dilatation and/or ectasia, aneurysm and giant aneurysms. We compared patients with fever and four or five of the principal criteria (complete KD, cKD) to the other patients (iKD). Compared with healthy controls a significant decrease in MPV and PDW (p platelet count, CRP and ESR (p all children with KD. There were no statistically differences in MPV and PDW between KD with CALs and KD without CALs (p > 0.05). However, MPV and PDW were significantly lower in patients with iKD than in group with cKD (p = 0.003, p = 0.014, respectively). It was first shown that patients with KD have lower MPV and PDW than control subjects. The diagnosis of iKD is challenging but can be supported by the presence of lower MPV and PDW.

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

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    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) 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 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.

  9. The predictive value of mean platelet volume, plateletcrit and red cell distribution width in the differentiation of autoimmune gastritis patients with and without type I gastric carcinoid tumors.

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    Tüzün, Ali; Keskin, Onur; Yakut, Mustafa; Kalkan, Cagdas; Soykan, Irfan

    2014-01-01

    Autoimmune gastritis is an autoimmune and inflammatory condition that may predispose to gastric carcinoid tumors or adenocarcinomas. The early diagnosis of these tumors is important in order to decrease morbidity and mortality. Platelet indices such as mean platelet volume and plateletcrit levels increase in inflammatory, infectious and malign conditions. The primary aim of this study was to explore wheter platelet indices and red cell distribution width have any predictive role in the discrimination of autoimmune gastritis patients with and without gastric carcinoid tumors. Also secondary aim of this study was to investigate whether any changes exist betwenn autoimmune gastritis and functional dyspepsia patients by means of platelet indices. Plateletcrit (0.22 ± 0.06 vs. 0.20 ± 0.03%, p gastritis patients compared to control group. Receiver operating curve analysis suggested that optimum plateletcrit cut-off point was 0.20% (AUC: 0.646), and 13.95% as the cut off value for red cell distribution width (AUC: 0.860). Although plateletcrit (0.22 ± 0.06 vs. 0.21 ± 0.04%, p = 0.220) and mean platelet volume (8.94 ± 1.44 vs. 8.68 ± 0.89 fl, p = 0.265) were higher in autoimmune gastritis patients without carcinoid tumor compared to patients with carcinoid tumors, these parameters were not statistically significant. Changes in plateletcrit and red cell distribution width values may be used as a marker in the discrimination of autoimmune gastritis and fucntional dyspepsia patients but not useful in patients with gastric carcinoid tumor type I.

  10. Mean platelet volume, red cell distribution width, platelet-to-lymphocyte and neutrophil-to-lymphocyte ratios in patients with ankylosing spondylitis and their relationships with high-frequency hearing thresholds.

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    Bozan, Nazim; Alpaycı, Mahmut; Aslan, Mehmet; Cankaya, Hakan; Kıroglu, Ahmet Faruk; Turan, Mahfuz; Ayral, Abdurrahman; Senkoy, Emre; Ilter, Server

    2016-11-01

    The mean platelet volume (MPV), red cell distribution width (RDW) and neutrophil-to-lymphocyte ratio (NLR) comprise laboratory markers in ankylosing spondylitis (AS). There is a controversy in the literature regarding which type of ear involvement is characteristic of AS. The aim of this study was to simultaneously investigate the MPV, RDW, platelet to lymphocyte (PLR) and NLR in patients with AS and their relationships with high-frequency hearing thresholds. Thirty patients with AS and 35 age-matched healthy subjects were included. Each subject was tested with low- (250, 500, 1000 and 2000 Hz) and high- (4000, 8000, 10,000, 12,000, 14,000 and 16,000 Hz) frequency audiometry. Additionally, the case and control groups were evaluated regarding the average hearing thresholds in bone conduction. The erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) levels were measured. The RDW, MPV, neutrophils, lymphocytes and platelet counts were evaluated with the complete blood count. Furthermore, the NLR and PLR were calculated. The complete blood count, platelet numbers, ESR, CRP and NLR levels were significantly increased in the AS patients compared with the healthy controls (p  0.05) in the AS patients compared with the healthy controls. The BASDAI score and disease duration were not correlated with the ESR, CRP levels, MPV, PLR, RDW or NLR in patients with AS (all; p > 0.05). The AS patients had increased average measurement values for the hearing threshold in both ears at frequencies of 250, 500, 1000 and 2000 Hz; however, there was no statistically significant difference (p > 0.05). The average values of the hearing threshold in both ears at the high frequencies of 4000, 6000, 8000, 10,000, 12,000 and 14,000 Hz were significantly increased in the case group; however, it was not significantly increased at 16,000 Hz. The current study is the first to investigate the PLR, NLR, MPV and RDW levels in acute AS. We identified a significantly increased

  11. Evaluation of the Mean Platelet Volume and Red Cell Distribution Width in FMF: Are They Related to Subclinical Inflammation or Not?

    OpenAIRE

    Gozde Yildirim Cetin; Ozlem Gul; Fatma Kesici-Metin; İrem Gokalp; Mehmet Sayarlıoglu

    2014-01-01

    In this paper we want to demonstrate whether higher than normal levels of RDW, and lower than normal levels of MPV can be used as indicators of subclinical inflammation and tools for treatment decision in FMF or not. The participants in this study included 89 patients with FMF during attack-free periods and 30 healthy controls. The RDW and platelet counts were significantly higher, while the MPV was significantly lower in the patients with FMF group than healthy control group (P < 0.001; P = ...

  12. Evaluation of the Mean Platelet Volume and Red Cell Distribution Width in FMF: Are They Related to Subclinical Inflammation or Not?

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    Yildirim Cetin, Gozde; Gul, Ozlem; Kesici-Metin, Fatma; Gokalp, İrem; Sayarlıoglu, Mehmet

    2014-01-01

    In this paper we want to demonstrate whether higher than normal levels of RDW, and lower than normal levels of MPV can be used as indicators of subclinical inflammation and tools for treatment decision in FMF or not. The participants in this study included 89 patients with FMF during attack-free periods and 30 healthy controls. The RDW and platelet counts were significantly higher, while the MPV was significantly lower in the patients with FMF group than healthy control group (P FMF group, a negative correlation was found between the MPV and RDW values (P FMF patients. But other strong predisposing factors affecting subclinical inflammation in FMF should be considered. Further studies with large numbers of patients are needed. Treatment of FMF should include not only prevention of acute attacks but also decreasing of the subclinical inflammation.

  13. Evaluation of the Mean Platelet Volume and Red Cell Distribution Width in FMF: Are They Related to Subclinical Inflammation or Not?

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    Gozde Yildirim Cetin

    2014-01-01

    Full Text Available In this paper we want to demonstrate whether higher than normal levels of RDW, and lower than normal levels of MPV can be used as indicators of subclinical inflammation and tools for treatment decision in FMF or not. The participants in this study included 89 patients with FMF during attack-free periods and 30 healthy controls. The RDW and platelet counts were significantly higher, while the MPV was significantly lower in the patients with FMF group than healthy control group (P<0.001; P=0.005; P<0.001, resp.. In the attack-free FMF group, a negative correlation was found between the MPV and RDW values (P<0.001, r=-0.40. The positive correlation was found between the RDW and ESR (r=0.23, P=0.028. And the negative correlation was found between the MPV and CRP (r=-0.216, P=0.042. Consequently, our results suggest that low MPV and high RDW levels may provide additional information about subclinical inflammation in FMF patients. But other strong predisposing factors affecting subclinical inflammation in FMF should be considered. Further studies with large numbers of patients are needed. Treatment of FMF should include not only prevention of acute attacks but also decreasing of the subclinical inflammation.

  14. Nano-scaled graphene platelets with a high length-to-width aspect ratio

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    Zhamu, Aruna; Guo, Jiusheng; Jang, Bor Z.

    2010-09-07

    This invention provides a nano-scaled graphene platelet (NGP) having a thickness no greater than 100 nm and a length-to-width ratio no less than 3 (preferably greater than 10). The NGP with a high length-to-width ratio can be prepared by using a method comprising (a) intercalating a carbon fiber or graphite fiber with an intercalate to form an intercalated fiber; (b) exfoliating the intercalated fiber to obtain an exfoliated fiber comprising graphene sheets or flakes; and (c) separating the graphene sheets or flakes to obtain nano-scaled graphene platelets. The invention also provides a nanocomposite material comprising an NGP with a high length-to-width ratio. Such a nanocomposite can become electrically conductive with a small weight fraction of NGPs. Conductive composites are particularly useful for shielding of sensitive electronic equipment against electromagnetic interference (EMI) or radio frequency interference (RFI), and for electrostatic charge dissipation.

  15. Width Distributions for Convex Regular Polyhedra

    CERN Document Server

    Finch, Steven R

    2011-01-01

    The mean width is a measure on three-dimensional convex bodies that enjoys equal status with volume and surface area [Rota]. As the phrase suggests, it is the mean of a probability density f. We verify formulas for mean widths of the regular tetrahedron and the cube. Higher-order moments of f_tetra and f_cube have not been examined until now. Assume that each polyhedron has edges of unit length. We deduce that the mean square width of the regular tetrahedron is 1/3+(3+sqrt(3))/(3*pi) and the mean square width of the cube is 1+4/pi.

  16. Red cell distribution width in type 2 diabetic patients

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    Nada AM

    2015-10-01

    Full Text Available Aml Mohamed Nada Department of Internal Medicine, Unit of Endocrinology, Diabetes and Metabolism, Faculty of Medicine, Mansoura University, Mansoura, Egypt Objective: To study the indices of some elements of the complete blood count, in type 2 diabetic patients, in comparison with nondiabetic healthy controls; and to find out the effects of glycemic control and different medications on these indices. To the best of our knowledge, this study is novel in our environment and will serve as a foundation for other researchers in this field. Methods: This retrospective study included 260 type 2 diabetic patients on treatment and 44 healthy control subjects. Sex, age, weight, height, blood pressure, complete blood count, fasting plasma glucose, hemoglobin A1c (HbA1c, and lipid profile data, were available for all of the study population. For diabetic patients, data on duration of diabetes and all medications were also available. Results: Red cell distribution width (RDW was significantly higher in diabetic patients than in control subjects (P=0.008. It was also higher in patients with uncontrolled glycemia (HbA1c >7% than those with good control (HbA1c ≤7%; P=0.035. Mean platelet volume (MPV was comparable in both diabetic patients and healthy controls (P=0.238. RDW and MPV did not significantly correlate with fasting plasma glucose, HbA1c, or duration of diabetes. Both aspirin and clopidogrel did not show a significant effect on MPV. Both insulin and oral hypoglycemic agents did not show a significant effect on RDW, mean corpuscular volume, MPV, platelet count, or white blood cell count. Diabetic patients treated with indapamide or the combined thiazides and angiotensin receptor blockers showed no significant difference in RDW when compared with the control subjects. Conclusion: RDW, which is recently considered as an inflammatory marker with a significant predictive value of mortality in diseased and healthy populations, is significantly higher in

  17. Statistical study of the pulse width distribution for radio pulsars

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Pulse widths of standard pulse profiles for 262 pulsars were measured by using the Urumqi 25 m radio telescope at 1.54 GHz.For the simplest case of circular emission beam,we applied Monte Carlo simulations to the pulse width distribution.Different density functions of magnetic inclination angle α and observer angle ξ were considered.Using Kolmogorov-Smirnov tests,we derived the most probable distribution for α and ξ.

  18. Narrowing of Terrace-width Distributions During Growth on Vicinals

    Science.gov (United States)

    Hamouda, Ajmi Bh.; Pimpinelli, A.; Einstein, T. L.

    2009-03-01

    Using kinetic Monte Carlo simulations for a generic minimal SOS model of vicinal surfaces, we compute the terrace-width distributions (TWDs) as a function of incident flux during homoepitaxial growth. We show that the distribution narrows markedly, U.B.P.-Clermont 2 as though there were a flux-dependent repulsion between steps, until the step picture fails at high flux. Using a Fokker-Planck approach, we analyze the evolution and saturation of this narrowing. We compare with a 1D model and with our simulations for narrowing due to an Ehrlich-Schwoebel barrier.

  19. Magnetohydrodynamic disc winds and line width distributions - II

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    Chajet, L. S.; Hall, P. B.

    2017-02-01

    We study AGN emission line profiles combining an improved version of the accretion disc-wind model of Murray & Chiang with the magnetohydrodynamic (MHD) model of Emmering et al. Here, we extend our previous work to consider central objects with different masses and/or luminosities. We have compared the dispersions in our model C IV line-width distributions to observational upper limit on that dispersion, considering both smooth and clumpy torus models. Following Fine et al., we transform that scatter in the profile line-widths into a constraint on the torus geometry and show how the half-opening angle of the obscuring structure depends on the mass of the central object and the accretion rate. We find that the results depend only mildly on the dimensionless angular momentum, one of the two integrals of motion that characterize the dynamics of the self-similar ideal MHD outflows.

  20. The distribution of equivalent widths in long GRB afterglow spectra

    CERN Document Server

    Postigo, A de Ugarte; Thoene, C C; Christensen, L; Gorosabel, J; Milvang-Jensen, B; Schulze, S; Jakobsson, P; Wiersema, K; Sanchez-Ramirez, R; Leloudas, G; Zafar, T; Malesani, D; Hjorth, J

    2012-01-01

    The extreme brightness of gamma-ray burst (GRB) afterglows and their simple spectral shape make them ideal beacons to study the interstellar medium of their host galaxies through absorption line spectroscopy. Using 69 low-resolution GRB afterglow spectra, we conduct a study of the rest-frame equivalent width (EW) distribution of features with an average rest-frame EW larger than 0.5 A. To compare an individual GRB with the sample, we develop EW diagrams as a graphical tool, and we give a catalogue with diagrams for the 69 spectra. We introduce a line strength parameter (LSP) that allows us to quantify the strength of the absorption features as compared to the sample by a single number. Using the distributions of EWs of single-species features, we derive the distribution of column densities by a curve of growth (CoG) fit. We find correlations between the LSP and the extinction of the GRB, the UV brightness of the host galaxies and the neutral hydrogen column density. However, we see no significant evolution of...

  1. Red cell distribution width predicts totally occluded infarct-related artery in NSTEMI.

    Science.gov (United States)

    Açıkgöz, Sadık Kadri; Akboğa, Mehmet Kadri; Açıkgöz, Eser; Yayla, Çağrı; Şensoy, Barış; Aydoğdu, Sinan

    2016-08-01

    Objective Since non-ST segment elevation myocardial infarction (NSTEMI) patients with totally occluded infarct-related artery (TO-IRA) have worse prognosis, it is important to recognize TO-IRA in NSTEMI. Red cell distribution width (RDW) and mean platelet volume (MPV) are novel markers of inflammation and oxidative stress and were associated with poor clinical outcomes in acute coronary syndrome. In the present study, association of RDW and MPV with the presence of TO-IRA in NSTEMI was investigated. Methods Data of 201 consecutive patients who underwent coronary angiography with a diagnosis of NSTEMI were analyzed. Independent predictors of TO-IRA were investigated with logistic regression analysis. Results Sixty-six (32.8%) of the patients had TO-IRA. In patients with TO-IRA, RDW and troponin-T were significantly higher and left ventricular ejection fraction (LVEF) was lower. MPV did not differ between groups. Circumflex (CX) IRA was more common in TO-IRA group. The ROC curve analysis showed that the RDW at a cut-point of 13.95% has 76% sensitivity and 66% specificity in detecting TO-IRA. RDW, troponin-T, LVEF and CX-IRA were independent predictors of TO-IRA in NSTEMI, but MPV was not. Conclusion RDW is a cheap and readily available marker that may have a role to predict TO-IRA in NSTEMI.

  2. Dependence of Wave Height Distribution on Spectral Width and Wave Steepness

    Institute of Scientific and Technical Information of China (English)

    文凡; 吴自库; 吕红民

    2004-01-01

    In this paper experimental wind wave data are analyzed. It is found that differences in spectral width will give rise to differences in wave height distribution. The effect of spectral width on the distribution is mainly in the high wave range.The effect of wave steepness is in low, medium and high wave ranges. In the high wave range the effect of spectral width is comparable to that of wave steepness. Differences in spectral width in the observations may give rise to discrepancies in the result when wave steepness is the only parameter in the distribution.

  3. Platelets

    Science.gov (United States)

    ... tiny fraction of the blood volume. The principal function of platelets is to prevent bleeding. Red blood cells are ... forming a long string. This illustrates the basic function of platelets, to stick to any foreign surface and then ...

  4. [Mathematical processing of human platelet distribution according to size for determination of cell heterogeneity].

    Science.gov (United States)

    Kosmovskiĭ, S Iu; Vasin, S L; Rozanova, I B; Sevast'ianov, V I

    1999-01-01

    The paper proposes a method for mathematical treatment of the distribution of human platelets by sizes to detect the heterogeneity of cell populations. Its use allowed the authors to identify three platelet populations that have different parameters of size distribution. The proposed method opens additional vistas for analyzing the heterogeneity of platelet populations without sophisticating experimental techniques.

  5. Elevated red blood cell distribution width is associated with intrahepatic cholestasis of pregnancy.

    Science.gov (United States)

    Vural Yilmaz, Zehra; Gencosmanoglu Turkmen, Gulenay; Daglar, Korkut; Yılmaz, Elif; Kara, Ozgur; Uygur, Dilek

    2017-01-01

    Intrahepatic cholestasis of pregnancy is the most common pregnancy specific liver disease and related with adverse maternal and perinatal outcome. Red blood cell distribution width, an anisocytosis marker in a complete blood count, has been used as an inflammation marker in various diseases. However the association of red blood cell distribution width with intrahepatic cholestasis of pregnancy is unknown. We aimed to evaluate the relationship between red blood cell distribution width and intrahepatic cholestasis of pregnancy. Ninety pregnant women with intrahepatic cholestasis of pregnancy and ninety healthy pregnant women were included in the study. Their clinical and laboratory characteristics including red blood cell distribution width, liver function tests, fasting and postprandial bile acid concentrations were analyzed. Serum red blood cell distribution width cell levels were significantly higher in pregnants with intrahepatic cholestasis of pregnancy than healthy pregnants. We also demonstrated that red blood cell distribution Width levels were higher in severe disease than mild disease and was significantly correlated with fasting and postprandial bile acid concentration in intrahepatic cholestasis of pregnancy group. Our study showed that red blood cell distribution width, an easy and inexpensive marker; were associated with intrahepatic cholestasis of pregnancy and can be used as a diagnostic and prognostic marker in intrahepatic cholestasis of pregnancy.

  6. A Novel Multisection Distributed Feedback Laser with Varied Ridge Width for Self-Pulsation Generation

    Institute of Scientific and Technical Information of China (English)

    WAN Qin; SUN Chang-Zheng; XIONG Bing; WANG Jian; LUO Yi

    2006-01-01

    @@ A novel ridge-waveguide multisection (MS) distributed feedback (DFB) laser, which consists of two identical DFB sections but different ridge widths, is proposed to generate beating-type self-pulsations (SPs).

  7. Resonance width distribution in RMT: Weak-coupling regime beyond Porter-Thomas

    Science.gov (United States)

    Fyodorov, Yan V.; Savin, Dmitry V.

    2015-05-01

    We employ the random matrix theory (RMT) framework to revisit the distribution of resonance widths in quantum chaotic systems weakly coupled to the continuum via a finite number M of open channels. In contrast to the standard first-order perturbation theory treatment we do not a priori assume the resonance widths being small compared to the mean level spacing. We show that to the leading order in weak coupling the perturbative χ^2M distribution of the resonance widths (in particular, the Porter-Thomas distribution at M = 1) should be corrected by a factor related to a certain average of the ratio of square roots of the characteristic polynomial (“spectral determinant”) of the underlying RMT Hamiltonian. A simple single-channel expression is obtained that properly approximates the width distribution also at large resonance overlap, where the Porter-Thomas result is no longer applicable.

  8. The role of red cell distribution width as a marker in inflammatory bowel disease

    OpenAIRE

    Arhan, Mehmet; ÖNAL, İbrahim Koral; Taş, Adnan; KURT, Mevlüt; Kalkan, İsmail Hakkı

    2011-01-01

    To determine whether red cell distribution width could be used for the assessment of disease activity in patients with inflammatory bowel disease. Materials and methods: A total of 165 patients with inflammatory bowel disease (105 ulcerative colitis; 60 Crohn's disease) and 43 healthy blood donors were included in this retrospective study in a tertiary care setting. The medical records of the patients were reviewed to note clinical activity indices, red cell distribution width, serum C ...

  9. Relationship between red cell distribution width and early renal injury in patients with gestational diabetes mellitus.

    Science.gov (United States)

    Cheng, Dong; Zhao, Jiangtao; Jian, Liguo; Ding, Tongbin; Liu, Shichao

    2016-09-01

    Previous studies found that red cell distribution width was related to adverse cardiovascular events. However, few studies reported the relationship between red cell distribution width and early-stage renal injury in pregnant women with gestational diabetes mellitus. Using a cross-sectional design, 334 pregnant women with gestational diabetes mellitus were enrolled according to the criterion of inclusion and exclusion. Demographic and clinical examination data were collected. Depended on the urine albumin, study population were divided into case group (n = 118) and control group (n = 216). Compared with control group, the case group tend to be higher red cell distribution width level (13.6 ± 0.9 vs.12.5 ± 0.6, p red cell distribution width was positively associated with albuminuria creatinine ratio (r = 0.567, p red cell distribution width was still associated with early-stage renal injury after adjusting for many other potential cofounders. Compared with the first quartile, the risk ratio of the second, the third and the fourth quartile were 1.38 (95%CI: 1.06-1.80), 1.57 (95%CI: 1.21-2.97), 2.71 (95%CI: 2.08-3.54), respectively. Besides, systolic blood pressure, estimated glomerular filtration rate, uric acid and blood urea nitrogen were also significantly associated with renal injury in gestational diabetes mellitus patients. The elevated red cell distribution width level might be a predictor of early-stage renal injury in pregnant women with gestational diabetes mellitus. As an easy and routine examination index, red cell distribution width may provide better clinical guidance when combined with other important indices.

  10. Parameters of the best approximation of reduced neutron widths distribution. Actinides

    CERN Document Server

    Sukhovoj, A M

    2011-01-01

    The data of ENDF/B-VII library on reduced neutron widths for nuclei 231Pa, 232Th, 233,234,235,236,238U, 237Np, 239,240,241,242Pu, 241,243Am and 243Cm (including p-resonances of 232Th, 238U, 239Pu) in form of cumulative sums in function on Gamma0n/ were approximated by variable number K of partial items 0widths of distribution number K in their total sum. The problems of their determination from distributions of different number of squares of normally distributed random values with variable threshold of loss of some part of the lowest widths values were studied. It was obtained for some part of neutron resonances that their mean amplitudes can considerably differ from zero value, and dispersions - from mean widths. And it is worth while to perform any quantitative analysis of widths distributions by means of comparison of different model notions with obligatory estimation of random ...

  11. Evaluation of Red Blood Cell Distribution Width in Patients with Cardiac Syndrome X

    Directory of Open Access Journals (Sweden)

    Ping Qing

    2013-01-01

    Full Text Available BACKGROUND: Cardiac syndrome X (CSX is a condition characterized by chest pain with normal coronary arteries. However, its pathogenesis has not fully been understood yet. Red blood cell distribution width (RDW has recently been suggested as a marker of acute and chronic cardiovascular diseases, while no data is available in patients with CSX.

  12. Red blood cell distribution width and 1-year mortality in acute heart failure

    NARCIS (Netherlands)

    van Kimmenade, Roland R. J.; Mohammed, Asim A.; Uthamalingam, Shanmugam; van der Meer, Peter; Felker, G. Michael; Januzzi, James L.

    2010-01-01

    Red blood cell distribution width (RDW) predicts mortality in chronic heart failure (HF) and stable coronary artery disease. The prognostic value of RDW in more acute settings such as acute HF, and its relative prognostic value compared with more established measures such as N-terminal pro-brain nat

  13. Computer Simulation of Fiber Length and Width Distribution for Two Poplar Woods

    Institute of Scientific and Technical Information of China (English)

    ZHANGDongmei; HOUZhuqiang; GUANNing

    2004-01-01

    Computer simulation was carried out on fiber length and width for plantation-grown Chinese white poplar (Populus tomentosa Cart. clone) and plantation-grown poplar 1-72 (P. x eurumericana (Dode) Guiner cv.). Skewness and kurtosis of measured results exhibited that distributions of the fiber length and width departured from normal distribution. Three-parameter Weibull density function was used in this investigation and the corresponding program was written with Turbo C. The results showed that profiles of simulated length and width histograms were similar to ones of measured histograms, and that there was a pretty good agreement between simulated and measured means of fiber length and width. There was a little influence on the simulated means from seed used in random number generator and number of simulated variables. That indicated that the simulation was steady when the seed and the number were altered. Different histograms can be obtained with different values of the location, the shape, and the scale parameter corresponding to different values of the minimum, the mean, and the standard deviation for fiber length and width. The simulation presented here can be used as a tool for the studies on the variations in fiber morphology.

  14. Terrace width distribution during unstable homoepitaxial growth of GaAs(110): An experimental study

    Energy Technology Data Exchange (ETDEWEB)

    Crespillo, M.L. [Instituto de Ciencia de Materiales de Madrid (ICMM-CSIC), Sor Juana Ines de la Cruz s/n, Cantoblanco, 28049 Madrid (Spain)]. E-mail: mcrespillo@icmm.csic.es; Sacedon, J.L. [Instituto de Ciencia de Materiales de Madrid (ICMM-CSIC), Sor Juana Ines de la Cruz s/n, Cantoblanco, 28049 Madrid (Spain); Tejedor, P. [Instituto de Ciencia de Materiales de Madrid (ICMM-CSIC), Sor Juana Ines de la Cruz s/n, Cantoblanco, 28049 Madrid (Spain)

    2006-07-15

    The temporal evolution of the step bunching instability formed during GaAs homoepitaxial growth on the GaAs(110) vicinal to (111)A has been studied by atomic force microscopy (AFM) and the step-step distribution has been quantified as a function of deposition time. Analysis of the AFM data has shown that neither the terrace width distribution (TWD) nor the terrace height distribution (THD) fit to a Gaussian function in the initial stages of growth, but both evolve with time as the bunching instability develops. After deposition of 500 ML of GaAs the TWD exhibits a clear Gaussian behavior while the THD is very well fitted to a Lorentzian distribution. The GaAs surface morphology initially shows a great dispersion in terrace height and width values with a clear anisotropy along the <001> tilt direction, but evidence of self-controlled growth is observed irrespective of layer thickness.

  15. Inferences from the Distributions of Fast Radio Burst Pulse Widths, Dispersion Measures and Fluences

    CERN Document Server

    Katz, J I

    2015-01-01

    The widths, dispersion measures, dispersion indices and fluences of Fast Radio Bursts (FRB) impose coupled constraints that all models must satisfy. Observation of dispersion indices close to their low density limit of $-2$ sets a model-independent upper bound on the electron density and a lower bound on the size of any dispersive plasma cloud. The non-monotonic dependence of burst widths (after deconvolution of instrumental effects) on dispersion measure excludes the intergalactic medium as the location of scattering that broadens the FRB in time. Temporal broadening far greater than that of pulsars at similar high Galactic latitudes implies that scattering occurs close to the sources, where high densities and strong turbulence are plausible. FRB energetics are consistent with supergiant pulses from young, fast, high-field pulsars at cosmological distances. The distribution of FRB dispersion measures is inconsistent with expanding clouds (such as SNR). It excludes space-limited distributions (such as the loc...

  16. Clinical application of whole blood red cell distribution width in lung cancer metastasis

    Institute of Scientific and Technical Information of China (English)

    徐阳飏

    2014-01-01

    Objective To investigate the clinical value of whole blood red cell distribution width(RDW)in discriminating lung cancer metastasis.Methods A retropective analysis was conducted on the patients who were initially diagnosed as primary lung cancer.A total of 525 patients were included for analysis between January 2012 and July2013,stratified by different stages and metastasis scenarios.RDW data was investigated.Kruskal-Wallis H tests

  17. Distribution of total radiation widths for neutron resonances of Pt isotopes

    Directory of Open Access Journals (Sweden)

    Koehler P.E.

    2015-01-01

    Full Text Available High quality neutron capture and transmission data were measured on isotopically enriched 192,194,195,196Pt and natural Pt samples at ORELA. R-matrix analysis of this data revealed resonance parameters for 159, 413, 423, 258, and 11 neutron resonances for neutron energies below 5.0, 16.0, 7.5, 16.0, and 5.0 keV for 192,194,195,196,198Pt+n, respectively. Earlier analysis of data on reduced neutron widths, Γ0n, showed that the distributions of Γ0n for 192,194Pt deviate significantly from the Porter-Thomas distribution (PTD predicted by random matrix theory. In this contribution we report on preliminary results of the analysis of distribution of total radiation widths, Γγ, in 192,194,195,196Pt+n reactions. Comparison of experimental data with predictions made within the nuclear statistical model indicates that standard models of Photon Strength Functions (PSFs and Nuclear Level Density predict Γγ distributions which are too narrow. We found that satisfactory agreement between experimental and simulated distributions can be obtained only by a strong suppression of the PSFs at low γ-ray energies and/or by violation of the usual assumption that primary transitions from neutron resonances follow the PTD. The shape of PSFs needed for reproduction of our Γγ data also nicely reproduces spectra from several (n,γ experiments on the neighbor nuclide 198Au.

  18. Neutrophil to Lymphocyte Ratio, Platelet to Lymphocyte Ratio, Mean Platelet Volume and Red Cell Distribution Width Measures in Bells Palsy

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    Caner Sahin

    2017-01-01

    CONCLUSION: Statistically significant changes in the neutrophil count and NLR were determined in the measurements between Bells Palsy and control group (p = 0.013, p = 0.016 respectively on admission. A grade of the disease and NLR measurements had no statistically significant connection. RDW value was investigated for the first time in the literature for Bells Palsy patients.

  19. Influence of leads widths distribution on turbulent heat transfer between the ocean and the atmosphere

    Directory of Open Access Journals (Sweden)

    S. Marcq

    2011-10-01

    Full Text Available Leads are linear-like structures of open water within the sea ice cover that develop as the result of fracturing due to divergence or shear. Through leads, air and water come into contact and directly exchange latent and sensible heat through convective processes driven by the large temperature and moisture differences between them. In the central Arctic, leads only cover 1 to 2% of the ocean during winter, but account for more than 80% of the heat fluxes. Furthermore, narrow leads (several meters are more than twice as efficient at transmitting turbulent heat than larger ones (several hundreds of meters. We show that lead widths are power law distributed, P(X~X−a with a>1, down to very small spatial scales (20 m or below. This implies that the open water fraction is by far dominated by very small leads. Using two classical formulations, which provide first order turbulence closure for the fetch-dependence of heat fluxes, we find that the mean heat fluxes (sensible and latent over open water are up to 55 % larger when considering the lead width distribution obtained from a SPOT satellite image of the ice cover, compared to the situation where the open water fraction constitutes one unique large lead and the rest of the area is covered by ice, as it is usually considered in climate models at the grid scale. This difference may be even larger if we assume that the power law scaling of lead widths extents down to smaller (~1 m scales. Such estimations may be a first step towards a subgrid scale parameterization of the spatial distribution of open water for heat fluxes calculations in ocean/sea ice coupled models.

  20. The Local Lyman-$\\alpha$ Forest; 1, Distribution of HI Absorbers, Doppler Widths, and Baryon Content

    CERN Document Server

    Penton, S V; Stocke, J T; Penton, Steven V.; Stocke, John T.

    1999-01-01

    In Paper I of this series (astro-ph/9911117) we described observations of 15 extragalactic targets taken with the Hubble Space Telescope GHRS/G160M grating for studies of the low-z Lya forest. We reported the detection of 110 Lya absorbers at significance level >3 sigma in the redshift range z=0.002-0.069, over a total pathlength of 116,000 km/s. In this second paper, we evaluate the physical properties of these Lya absorbers and compare them to their high-z counterparts. The distribution of Doppler parameters is similar to that at high redshift, with mean b = 35.0 +- 16.6 km/s. The true Doppler parameter may be somewhat lower, owing to component blends and non-thermal velocities. The distribution of equivalent widths exhibits a significant break at W~133mA, with an increasing number of weak absorbers (10mA-100mA). Adopting a curve of growth with b = 25 +- 5km/s and applying a sensitivity correction as a function of equivalent width and wavelength, we derive the distribution in column density, Nh^{-1.80+-0.05...

  1. The influence of row width and seed spacing on uniformity of plant spatial distributions

    DEFF Research Database (Denmark)

    Griepentrog, Hans W.; Olsen, Jannie Maj; Weiner, Jacob

    2009-01-01

    Crop performance and weed suppression increase with increasing crop spatial uniformity. We use spatial pattern simulations and field experiments to show the current state-of-the-art for spatial uniformity for different seeding technologies. We use Morisita's Index to quantify how changes in row...... width and evenness of spacing within rows influences two-dimensional spatial quality. The results can be used to define new requirements for improved seeding technologies to achieve higher benefits in sustainable crop production systems. In general it can be concluded that more even plant distributions...

  2. The relationship between subclinic atherosclerosis and red cell distribution width in patients with metabolic syndrome

    Directory of Open Access Journals (Sweden)

    Ali Rıza Gülcan

    2013-12-01

    Full Text Available Objectıve: We have investigated the possible associationbetween red cell distribution width (RDW and subclinicatherosclerosis which can assessed by carotidintima-media thickness (CIMT measurement in patientswith metabolic syndrome (MetS.Methods: 74 patients with MetS were enrolled to thestudy. Patients were divided into 2 groups according tocarotid intima-media thickness (CIMT measurement: 35patients with CIMT≥1.0 mm were at group 1 and 39 patientswith CIMT<1.0 mm were at group 2. RDW weremeasured using an automated blood cell counter.Results: The RDW level was not statistically significantin patients with CIMT≥1,0 mm than in patients withCIMT<1,0 mm (13.73±0.79% vs. 13.77±1.04 %; p=0.85.Conclusion: In our study, we found that RDW was notdifferent in the MetS patients with CIMT≥1.0 mm comparedwith the MetS patients with CIMT<1.0 mm.Key words: red cell distribution width, metabolic syndrome,complete blood count

  3. Increased red blood cell distribution width associates with cancer stage and prognosis in patients with lung cancer.

    Directory of Open Access Journals (Sweden)

    Yasuko Koma

    Full Text Available BACKGROUND: Red cell distribution width (RDW, one of many routinely examined parameters, shows the heterogeneity in erythrocyte size. We investigated the association of RDW levels with clinical parameters and prognosis of lung cancer patients. METHODS: Clinical and laboratory data from 332 patients with lung cancer in a single institution were retrospectively studied by univariate analysis. Kaplan-Meier survival analysis and Cox proportional hazard models were used to examine the effect of RDW on survival. RESULTS: THE RDW LEVELS WERE DIVIDED INTO TWO GROUPS: high RDW (>=15%, n=73 vs. low RDW, n=259 (<15%. Univariate analysis showed that there were significant associations of high RDW values with cancer stage, performance status, presence of other disease, white blood cell count, hemoglobin, mean corpuscular volume, platelet count, albumin level, C-reactive protein level, and cytokeratin 19 fragment level. Kruskal-Wallis tests revealed an association of RDW values with cancer stage in patients irrespective of comorbidity (patient with/without comorbidity: p<0.0001, patient without comorbidity: p<0.0001. Stages I-IV lung cancer patients with higher RDW values had poorer prognoses than those with lower RDW values (Wilcoxon test: p=0.002. In particular, the survival rates of stage I and II patients (n=141 were lower in the high RDW group (n=19 than in the low RDW group (n=122 (Wilcoxon test: p<0.001. Moreover, multivariate analysis showed higher RDW is a significant prognostic factor (p=0.040. CONCLUSION: RDW is associated with several factors that reflect inflammation and malnutrition in lung cancer patients. Moreover, high levels of RDW are associated with poor survival. RDW might be used as a new and convenient marker to determine a patient's general condition and to predict the mortality risk of lung cancer patients.

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

    Science.gov (United States)

    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.

  5. Narrowing of terrace-width distributions during growth on vicinal surfaces

    Science.gov (United States)

    Hamouda, A. BH.; Pimpinelli, A.; Einstein, T. L.

    2009-10-01

    We present analytic and numerical results for the steady-state, non-equilibrium terrace-width distribution (TWD) of steps during growth on vicinal surfaces. Kinetic Monte Carlo shows that the TWD narrows progressively with increasing flux until the model breaks down. The narrowing corresponds to kinetic repulsion between moving steps, due to the intrinsic asymmetry of the adatom diffusion current on a growing surface. With a 1-dimensional (1D) model, from a Burton-Cabrera-Frank approach, we make contact with previous work, in which the attachment asymmetry can also be due to electromigration or to asymmetry in attachment rates; we deduce an expression for the narrowing via a Fokker-Planck analysis. We illustrate how Ehrlich-Schwoebel barriers (although inducing an instability in 2D) also lead to such asymmetry and narrowing.

  6. Effects of $\\rho$-meson width on pion distributions in heavy-ion collisions

    CERN Document Server

    Huovinen, Pasi; Marczenko, Michał; Morita, Kenji; Redlich, Krzysztof; Sasaki, Chihiro

    2016-01-01

    The influence of the finite width of $\\rho$ meson on the pion momentum distribution is studied quantitatively in the framework of the S-matrix approach combined with a blast-wave model to describe particle emissions from an expanding fireball. We find that the proper treatment of resonances which accounts for their production dynamics encoded in data for partial wave scattering amplitudes can substantially modify spectra of daughter particles originating in their two body decays. In particular, it results in an enhancement of the low-$p_T$ pions from the decays of $\\rho$ mesons which improves the quantitative description of the pion spectra in heavy ion collisions obtained by the ALICE collaboration at the LHC energy.

  7. Magnetohydrodynamic DiscWinds and LineWidth Distributions.II

    CERN Document Server

    Chajet, L S

    2016-01-01

    We study AGN emission line profiles combining an improved version of the accretion disc-wind model of Murray & Chiang with the magneto-hydrodynamic model of Emmering et al. (1992). Here we extend our previous work to consider central objects with different masses and/or luminosities. We have compared the dispersions in our model C IV linewidth distributions to observational upper limit on that dispersion, considering both smooth and clumpy torus models. Following Fine et al., we transform that scatter in the profile line-widths into a constraint on the torus geometry and show how the half-opening angle of the obscuring structure depends on the mass of the central object and the accretion rate. We find that the results depend only mildly on the dimensionless angular momentum, one of the two integrals of motion that characterise the dynamics of the self-similar ideal MHD outflows

  8. [Red cell distribution width as a risk marker in patients with cardiovascular diseases].

    Science.gov (United States)

    Alcaíno, Hernán; Pozo, José; Pavez, Mario; Toledo, Humberto

    2016-05-01

    Red cell distribution width (RDW) is a measurement of the variation in size, as well as an index of heterogeneity of erythrocytes, which is used in combination with other hematologic parameters as an aid to the differential diagnosis of hypochromic anemia. RDW could also serve as a biomarker in the diagnosis and prognosis patients with cardiovascular diseases. However, it is unclear whether the increased heterogeneity is the cause or consequence of other pathophysiological conditions such as renal failure, malnutrition, inflammation and oxidative stress, which among other conditions are actively involved in the genesis and progression of cardiovascular diseases. The aim of this review is to show and discuss recent evidence about the role of RDW measurement as an aid in the diagnosis and prognosis of patients with such diseases. Besides being a simple, inexpensive and routinely measured parameter, it could help in the stratification of patients according to their risk in clinical practice.

  9. Red cell distribution width in anemic patients undergoing transcatheter aortic valve implantation

    Institute of Scientific and Technical Information of China (English)

    Katharina Hellhammer; Tobias Zeus; Pablo E Verde; Verena Veulemanns; Lisa Kahlstadt; Georg Wolff; Ralf Erkens; Ralf Westenfeld; Eliano P Navarese; Marc W Merx; Tienush Rassaf; Malte Kelm

    2016-01-01

    AIM: To determine the impact of red blood cell distribution width on outcome in anemic patients undergoing transcatheter aortic valve implantation(TAVI).METHODS: In a retrospective single center cohort study we determined the impact of baseline red cell distribution width(RDW) and anemia on outcome in 376 patients with aortic stenosis undergoing TAVI. All patients were discussed in the institutional heart team and declined for surgical aortic valve replacement due to high operative risk. Collected data included patient characteristics, imaging findings, periprocedural in hospital data, laboratory results and follow up data. Blood samples for hematology and biochemistry analysis were taken from every patient before and at fixed intervals up to 72 h after TAVI including blood count and creatinine. Descriptive statistics were used for patient’s characteristics. KaplanMeier survival curves were used for time to event outcomes. A recursive partitioning regression and classification was used to investigate the association between potential risk factors and outcome variables.RESULTS: Mean age in our study population was 81 ± 6.1 years. Anemia was prevalent in 63.6%(n = 239) of our patients. Age and creatinine were identified as risk factors for anemia. In our study population, anemia per se did influence 30-d mortality but did not predict longterm mortality. In contrast, a RDW > 14% showed to be highly predictable for a reduced short- and longterm survival in patients with aortic valve disease after TAVI procedure.CONCLUSION: Age and kidney function determine the degree of anemia. The anisocytosis of red blood cells in anemic patients supplements prognostic information in addition to that derived from the WHO-based definition of anemia.

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

    DEFF Research Database (Denmark)

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

    2016-01-01

    . METHODS: Citrate- and EDTA-anticoagulated blood from healthy volunteers were centrifuged at 80-10,000 g for 5-15 min to prepare plasma and platelet-rich plasma. Pre-analytical platelet activation was assessed by flow cytometric measurement of platelet P-selectin (CD62p) expression. Blood cell counts, mean...... platelet volume (MPV), immature platelet fraction (IPF), and platelet distribution width (PDW) were measured. Platelet aggregation in platelet-rich plasma induced by arachidonic acid (AA), ADP or thrombin receptor activator peptide-6 (TRAP) was tested by 96-well aggregometry. RESULTS: The median percentage...... of platelets expressing P-selectin in citrate- and EDTA-plasma centrifuged at 2000 g for 10 min were 43% [interquartile range (IQR), 38%-53%] and 56% (IQR, 31%-78%), respectively (p=0.82). Platelet-rich plasma prepared at 100-250 g for 10 min had significantly lower platelet P-selectin expression (11%-15%), p...

  11. Predictive value of red blood cell distribution width for coronary artery lesions in patients with Kawasaki disease.

    Science.gov (United States)

    Xu, Haiyan; Fu, Songling; Wang, Wei; Zhang, Qing; Hu, Jian; Gao, Lichao; Zhu, Weihua; Gong, Fangqi

    2016-08-01

    Recent studies have shown that elevated red blood cell distribution width is associated with poor outcome in cardiovascular diseases. In order to assess the predictive value of red blood cell distribution width, before treatment with intravenous immunoglobulins, for coronary artery lesions in patient with Kawasaki disease, we compared 83 patients with coronary artery lesions and 339 patients without coronary artery lesions before treatment with intravenous immunoglobulin. Clinical, echocardiographic, and biochemical values were evaluated along with red blood cell distribution width. A total of 422 consecutive patients with Kawasaki disease were enrolled into our study. According to receiver operating characteristic curve analysis, the optimal red blood cell distribution width cut-off value for predicting coronary artery lesions was 14.55% (area under the curve was 0.721; p=0.000); eighty-three patients (19.7%) had coronary artery lesions, and 70% of the patients with coronary artery lesions had red blood cell distribution width level >14.55%. Logistic regression analysis revealed that fever duration >14 days (odds ratio was 3.42, 95% confidence interval was 1.27-9.22; p=0.015), intravenous immunoglobulin resistance (odds ratio was 2.33, 95% confidence interval was 1.02-5.29; p=0.04), and red blood cell distribution width >14.55% (odds ratio was 3.49, 95% confidence interval was 2.01-6.05; p=0.000) were independent predictors of coronary artery lesions in patients with Kawasaki disease. In Conclusion, red blood cell distribution width may be helpful for predicting coronary artery lesions in patients with Kawasaki disease.

  12. Statins have beneficial effects on platelet free radical activity and intracellular distribution of GTPases in hyperlipidaemia.

    Science.gov (United States)

    Hamilton, Paul K; Hughes, Sinead M T; Plumb, Richard D; Devine, Adrian; Leahey, William; Lyons, Kristopher S; Johnston, Dennis; McVeigh, Gary E

    2010-03-01

    In addition to lowering cholesterol, statins may alter endothelial release of the vasodilator NO and harmful superoxide free radicals. Statins also reduce cholesterol intermediates including isoprenoids. These are important for post-translational modification of substances including the GTPases Rho and Rac. By altering the membrane association of these molecules, statins affect intracellular positioning and hence activity of a multitude of substances. These include eNOS(endothelial NO synthase), which produces NO (inhibited by Rho), and NADPH oxidase, which produces superoxide (dependent on Rac). Statins may improve endothelial function by enhancing production of NO while decreasing superoxide production. A total of 40 hypercholesterolaemic patients were randomized to treatment with either atorvastatin or placebo; 20 normolipidaemic patients were also studied. Platelet nitrite, NO and superoxide were examined as was the cellular distribution of the GTPases Rho and Rac at baseline and after 8 weeks of treatment.Following atorvastatin therapy, platelet NO was increased (3.2 pmol/10(8) platelets) and superoxide output was attenuated [-3.4 pmol min(-1) (10(8) platelets)(-1)] when compared with placebo. The detection of both Rho and Rac was significantly reduced in the membranes of platelets, implying reduced activity. In conclusion, the results of the present study show altered NO/superoxide production following statin therapy. A potential mechanism for this is the change in the distribution of intracellular GTPases, which was considered to be secondary to decreases in isoprenoid intermediates, suggesting that the activity of the former had been affected by atorvastatin.

  13. The Evaluation of Red Cell Distribution Width in Chronic Hemodialysis Patients

    Directory of Open Access Journals (Sweden)

    Hikmet Tekce

    2014-01-01

    Full Text Available Background. Red cell distribution width (RDW has been used as a marker of iron deficiency; however, it is accepted as a marker of cardiovascular survival. We aimed to study RDW levels in hemodialysis (HD patients and the association between RDW and inflammatory, nutritional, and volume markers. Methods. We included 296 HD patients with sufficient iron storage and without anemia or hypervolemia. We grouped patients into four groups according to clinical parameters, albumin, and C-reactive protein (CRP. Results. The lowest RDW levels were found in group 1 (13.2%. Although RDW of group 2 was higher than that of group 1, it was still in normal range (14.7% versus 13.2%, P=0.028. RDW levels of groups 3 (17.8% and 4 (18.5% were significantly higher than those of groups 1 and 2 and above normal range. A positive correlation was detected between RDW and HD duration, interdialytic weight gain (IDWG, serum phosphate, and CRP levels and a negative correlation was detected with serum albumin. HD duration, CRP, IDWG, and serum albumin have been found as independent predictors of RDW elevation. Conclusions. Results of the present study reflect adverse effects of inflammation, malnutrition, and excess IDWG on RDW elevation in an HD study cohort with sufficient iron storage and without anemia and hypervolemia.

  14. Red blood cell distribution width and iron deficiency anemia among pregnant Sudanese women

    Directory of Open Access Journals (Sweden)

    Abdelrahman Esam G

    2012-12-01

    Full Text Available Abstract Background Iron deficiency anemia (IDA is a major health problem during pregnancy and it has adverse effects on the mother and the newborn. Red cell distribution width (RDW, which is a quantitative measure for red cell size variation (anisocytosis, is a predictor of IDA. Little is known regarding RDW and IDA during pregnancy. Methods A cross sectional study was conducted at the antenatal clinic of Khartoum Hospital, Sudan, to determine the performance of RDW in the diagnosis of IDA using serum ferritin as a gold standard. Results Among 194 pregnant women with a gestational period of 21.4 ± 6.5 weeks, 57 (29.4% had IDA according to serum ferritin levels (14.5. The sensitivity, specificity, positive predictive value, and negative predictive value of RDW where serum ferritin was the gold standard were 43.8% (95% CI: 31.4–57.0%, 73.7% (95% CI: 65.8–80.5%, 41.0% (95% CI: 29.2–53.6%, and 76.0% (95% CI: 68.1–82.6%, respectively. Conclusions In this study, we found that RDW has a poor performance in diagnosing IDA among pregnant women compared with serum ferritin as the gold standard. Virtual slides The virtual slides for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1721072967826303

  15. Association of erythrocyte deformability with red blood cell distribution width in metabolic diseases and thalassemia trait.

    Science.gov (United States)

    Vayá, Amparo; Alis, Rafael; Suescún, Marta; Rivera, Leonor; Murado, Julian; Romagnoli, Marco; Solá, Eva; Hernandez-Mijares, Antonio

    2015-01-01

    Increased red blood distribution width (RDW) in anemia is related to disturbances in the cellular surface/volume ratio, usually accompanied by morphological alterations, while it has been shown in inflammatory diseases that the activity of pro-inflammatory cytokines disturbing erythropoiesis increases RDW. Recently it has been reported that higher RDW is related with decreased erythrocyte deformability, and that it could be related with the association of RDW and increased risk of cardiovascular diseases. In order to analyze the influence of morphological alterations and proinflammatory status on the relationship between RDW and erythrocyte deformability, we analyzed erythrocyte deformability along with RDW and other hematological and biochemical parameters in 36 α-thalassemia, 20 β-thalassemia, 20 δβ-thalassemia trait carriers, 61 metabolic syndrome patients and 76 morbidly obese patients. RDW correlated inversely with erythrocyte deformability in minor β-thalassemia (r =-0.530, p thalassemia is often accompanied by more marked cell-shaped perturbations than other thalassemia traits. This could be the reason for this negative association only in this setting. Higher anisocytosis seems to be associated with greater morphologic alterations (shape/volume), which reduce erythrocyte deformability. The proinflammatory profile in metabolic patients can be related to the positive association of RDW with erythrocyte deformability found in these patients. However, further research is needed to explain the mechanisms underlying this association.

  16. Red Blood Cell Distribution Width in Patients With Chronic Obstructive Pulmonary Disease and Healthy Subjects.

    Science.gov (United States)

    Ozgul, Guler; Seyhan, Ekrem Cengiz; Özgül, Mehmet Akif; Günlüoğlu, Mehmet Zeki

    2017-03-01

    Chronic obstructive pulmonary disease (COPD) increases the risk of cardiovascular disease (CVD). Red blood cell distribution width (RDW) is accepted as a powerful predictor of outcomes in patients with CVD. To study RDW in patients with COPD, and to compare the value of this measurement with clinical, echocardiographic, nutritional and laboratory status. Secondly, we aimed to determine the effect of smoking on RDW values in healthy subjects. One hundred and seventy-five patients with stable COPD and 210 healthy controls were enrolled in the study. Demographic, clinical, nutritional status, echocardiographic, and laboratory characteristics, RDW values were recorded and compared. RDW values were higher in the COPD group than in controls (15±2.3% vs. 13.8±2.5%, ppulmonary hypertension (PAH) (r=0.1, P=.02), and presence of CVD (r=0.24, P=.02). In multivariable logistic regression suggested that presence of CVD (4.3; 95% CI: 1.3 to 11; P=.01), and presence of RVD (3.1; 95% CI: 1.7 to 8.3; P=.02) were independently related to elevated RDW levels in COPD patients. In the healthy population, correlations analysis showed only a significant correlation between RDW and cigarette smoking years (r=0.57, P<.001). RDW is independently associated with CVD and RVD in patients with COPD. In the healthy population, RDW is also associated with smoking status. Copyright © 2016 SEPAR. Publicado por Elsevier España, S.L.U. All rights reserved.

  17. Ratio of spleen diameter to red blood cell distribution width: a novel indicator for celiac disease.

    Science.gov (United States)

    Balaban, Daniel Vasile; Popp, Alina; Lungu, Andrei Marian; Costache, Raluca Simona; Anca, Ioana Alina; Jinga, Mariana

    2015-04-01

    Celiac disease (CD) is currently considerably underdiagnosed, setting the need for developing tools to select patients with probability of CD, who warrant further testing. Red blood cell distribution width (RDW) has been shown in previous studies to be a sensitive predictor for CD, but it lacks specificity. Splenic hypotrophy is also noted frequently in celiac patients. Our aim was to evaluate if spleen diameter to RDW ratio can be used as an indicator for CD. We evaluated 15 newly diagnosed CD patients, 52 patients with inflammatory bowel disease, and 35 patients with irritable bowel syndrome (IBS). We evaluated the differences in spleen diameter, RDW, and their ratio among the four groups. Two-thirds of the CD patients had elevated RDW, compared to 9% in the IBS group. A small spleen was seen in 80% of the celiacs, compared to 21.9% in the ulcerative colitis group, 10% in the Crohn disease group, and 9% in the IBS group. A spleen diameter to RDW ratio under 6 had a sensitivity of 73.3% and specificity of 88.5% in predicting CD, with an AUROC of 0.737. Spleen diameter to RDW ratio is a simple, widely available score, which can be used to select adult patients with probability of CD.

  18. Red cell distribution width is associated with albuminuria in adults with familial Mediterranean fever.

    Science.gov (United States)

    Uslu, Ali Ugur; Yonem, Ozlem; Aydin, Bahattin; Uncu, Tunahan; Seven, Dogan; Balta, Sevket; Cicekli, Emre

    2016-04-01

    Systematic inflammation, enhanced oxidative stress, and endothelial dysfunction are important for evolution and progression of renal damage, and they cause an increase in red cell distribution width (RDW). Familial Mediterranean fever (FMF) patients who are in the attack-free period and its relation with albuminuria and performance on assessment of microalbuminuria. One hundred and seventy-seven patients who had been diagnosed in accordance with Tel-hoshmer criteria and were in the attack-free period, and 143 age- and sex-matched healthy individuals were enrolled in our study. RDW values of FMF patients were higher compared with those of the controls (13.85 ± 1.07 and 13.15 ± 0.91, respectively; p < 0.0001). RDW values of FMF patients with microalbuminuria were higher compared with those of FMF patients with normoalbuminuria and the control group (p = 0.002 and p < 0.0001, respectively). RDW values of FMF patients with normoalbuminuria were higher compared with those of the control group (p < 0.0001). We have showed RDW levels are positively correlated with albuminuria (r = 0.185, p = 0.014). When assessing microalbuminuria with RDW in the patients, a cutoff value of 13.85 with sensitivity of 60%, specificity of 62%, and p = 0.002 (area under curve: 0.651, 95% confidence interval 0.563-0.738), was observed according to receiver-operating characteristic curve analysis. Among the various variables associated with albuminuria in multivariate logistic regression analyses, RDW remained an independent predictor of albuminuria (95% confidence interval 0.479-0.942, p = 0.021). RDW may be associated with albuminuria in FMF patients and it can be a predictor of microalbuminuria. Copyright © 2016. Published by Elsevier Taiwan.

  19. Admission red cell distribution width: a novel predictor of massive transfusion after injury.

    Science.gov (United States)

    Paulus, Elena M; Weinberg, Jordan A; Magnotti, Louis J; Sharpe, John P; Schroeppel, Thomas J; Fabian, Timothy C; Croce, Martin A

    2014-07-01

    Admission red cell distribution width (aRDW) has been shown to predict mortality in trauma patients by an unclear mechanism. It has been speculated that aRDW is a marker of chronic health status, but elevated RDW may also reflect recent hemorrhage. We hypothesized that aRDW is a predictor of major hemorrhage in trauma patients. Shock trauma patients at a Level I trauma center over 6.5 years were evaluated. Patients were stratified by aRDW quintile (Q1: less than 13%, Q2: 13.1 to 13.5%, Q3: 13.6 to 14.0%, Q4: 14.1 to 14.9%, Q5: 15.0% or greater). Massive transfusion (MT) was defined as 10 or more packed red blood cells in the first 24 hours. From multiple logistic regression, odds ratios with 95 per cent confidence intervals (CIs) were determined to evaluate the association between aRDW quintile and MT. Three thousand nine hundred ninety-four met study criteria. Overall MT incidence was 10 per cent and in-hospital mortality was 17 per cent. MT and mortality increased in a stepwise fashion by aRDW quintile (P < 0.0001). From logistic regression, a threefold increased odds of MT was associated with aRDW Q4 (CI, 1.81 to 4.92), and a 3.5-fold increased odds of MT was associated with aRDW Q5 (CI, 2.70 to 5.83). aRDW independently predicted MT, suggesting that elevated aRDW is an indicator of major hemorrhage in trauma patients. The association between aRDW and mortality in trauma patients may be explained by acute hemorrhage rather than chronic health status.

  20. Red cell distribution width and neurological scoring systems in acute stroke patients

    Directory of Open Access Journals (Sweden)

    Kara H

    2015-03-01

    Full Text Available Hasan Kara,1 Selim Degirmenci,1 Aysegul Bayir,1 Ahmet Ak,1 Murat Akinci,1 Ali Dogru,1 Fikret Akyurek,2 Seyit Ali Kayis3 1Department of Emergency Medicine, Faculty of Medicine, Selcuk University, Konya, Turkey; 2Department of Biochemistry, Faculty of Medicine, Selcuk University, Konya, Turkey; 3Department of Biostatistics, Faculty of Medicine, Karabuk University, Karabuk, Turkey Objectives: The purpose of the present study was to evaluate the association between the red blood cell distribution width (RDW and the Glasgow Coma Scale (GCS, Canadian Neurological Scale (CNS, and National Institutes of Health Stroke Scale (NIHSS scores in patients who had acute ischemic stroke. Methods: This prospective observational cohort study included 88 patients who have had acute ischemic stroke and a control group of 40 patients who were evaluated in the Emergency Department for disorders other than acute ischemic stroke. All subjects had RDW determined, and stroke patients had scoring with the GCS, CNS, and NIHSS scores. The GCS, CNS, and NIHSS scores of the patients were rated as mild, moderate, or severe and compared with RDW. Results: Stroke patients had significantly higher median RDW than control subjects. The median RDW values were significantly elevated in patients who had more severe rather than milder strokes rated with all three scoring systems (GCS, CNS, and NIHSS. The median RDW values were significantly elevated for patients who had moderate rather than mild strokes rated by GCS and CNS and for patients who had severe rather than mild strokes rated by NIHSS. The area under the receiver operating characteristic curve was 0.760 (95% confidence interval, 0.676–0.844. Separation of stroke patients and control groups was optimal with RDW 14% (sensitivity, 71.6%; specificity, 67.5%; accuracy, 70.3%. Conclusion: In stroke patients who have symptoms <24 hours, the RDW may be useful in predicting the severity and functional outcomes of the stroke

  1. Improved Early Detection of Sepsis in the ED With a Novel Monocyte Distribution Width Biomarker.

    Science.gov (United States)

    Crouser, Elliott D; Parrillo, Joseph E; Seymour, Christopher; Angus, Derek C; Bicking, Keri; Tejidor, Liliana; Magari, Robert; Careaga, Diana; Williams, JoAnna; Closser, Douglas R; Samoszuk, Michael; Herren, Luke; Robart, Emily; Chaves, Fernando

    2017-09-01

    Sepsis most often presents to the ED, and delayed detection is harmful. WBC count is often used to detect sepsis, but changes in WBC count size also correspond to sepsis. We sought to determine if volume increases of circulating immune cells add value to the WBC count for early sepsis detection in the ED. A blinded, prospective cohort study was conducted in two different ED populations within a large academic hospital. Neutrophil and monocyte volume parameters were measured in conjunction with routine CBC testing on a UniCel DxH 800 analyzer at the time of ED admission and were evaluated for the detection of sepsis. There were 1,320 subjects in the ED consecutively enrolled and categorized as control subjects (n = 879) and those with systemic inflammatory response syndrome (SIRS) (n = 203), infection (n = 140), or sepsis (n = 98). Compared with other parameters, monocyte distribution width (MDW) best discriminated sepsis from all other conditions (area under the curve [AUC], 0.79; 95% CI, 0.73-0.84; sensitivity, 0.77; specificity, 0.73; MDW threshold, 20.50), sepsis from SIRS (AUC, 0.74; 95% CI, 0.67-0.84), and severe sepsis from noninfected patients in the ED (AUC, 0.88; 95% CI, 0.75-0.99; negative predictive value, 99%). The added value of MDW to WBC count was statistically significant (AUC, 0.89 for MDW + WBC vs 0.81 for WBC alone; P detection of sepsis compared with WBC count alone at the time of admission in the ED. ClinicalTrials.gov; No.: NCT02232750; URL: www.clinicaltrials.gov. Copyright © 2017 American College of Chest Physicians. Published by Elsevier Inc. All rights reserved.

  2. Usefulness of elevated red cell distribution width for predicting systemic inflammatory response syndrome after extracorporeal circulation.

    Science.gov (United States)

    Özeren, M; Aytaçoğlu, B; Vezir, Ö; Karaca, K; Akın, R; Sucu, N

    2015-10-01

    Cardiac surgical operations performed by using extracorporeal circulation (ECC) lead to a systemic inflammatory response (SIR). Sometimes SIR may turn into a severe state, the systemic inflammatory response syndrome (SIRS) that usually has a poor outcome with no specific clinical tools described for its prediction. Red cell distribution width (RDW) is a routine hematological parameter. It has been proposed as a marker of morbidity and mortality in various clinical conditions. We aimed to investigate the relationship between high RDW and SIRS which is triggered by ECC. Eleven hundred consecutive patients who underwent elective heart surgery with the use of ECC were retrospectively analyzed. A total of 19 patients fulfilled the described SIRS criteria and 20 consecutive patients were selected as the control group. RDW and other laboratory parameters, preoperative clinical status, operative data and postoperative data were compared between the SIRS and the control groups. Baseline characteristics of the patient groups were similar. Significant mortality was found in the SIRS group; 18 (94.73%) patients and 2 (10%) patients in the control group (p SIRS group vs the control group (15.02 ± 2.03 vs 13.01 ± 1.93, respectively, p SIRS development (OR for RDW levels exceeding 13.5%; 95% confidence limits of 1.0-1.3; p SIRS group (p = 0.049). Increased RDW was significantly associated with increased risk of SIRS after ECC. The results of this study suggest that paying attention to RDW might provide valuable clinical information for predicting SIRS development among patients who are candidates for open heart surgery, without incurring additional costs. © The Author(s) 2015.

  3. On microphysical processes of noctilucent clouds (NLC: observations and modeling of mean and width of the particle size-distribution

    Directory of Open Access Journals (Sweden)

    G. Baumgarten

    2010-07-01

    Full Text Available Noctilucent clouds (NLC in the polar summer mesopause region have been observed in Norway (69° N, 16° E between 1998 and 2009 by 3-color lidar technique. Assuming a mono-modal Gaussian size distribution we deduce mean and width of the particle sizes throughout the clouds. We observe a quasi linear relationship between distribution width and mean of the particle size at the top of the clouds and a deviation from this behavior for particle sizes larger than 40 nm, most often in the lower part of the layer. The vertically integrated particle properties show that 65% of the data follows the linear relationship with a slope of 0.42±0.02 for mean particle sizes up to 40 nm. For the vertically resolved particle properties (Δz = 0.15 km the slope is comparable and about 0.39±0.03. For particles larger than 40 nm the distribution width becomes nearly independent of particle size and even decreases in the lower part of the layer. We compare our observations to microphysical modeling of noctilucent clouds and find that the distribution width depends on turbulence, the time that turbulence can act (cloud age, and the sampling volume/time (atmospheric variability. The model results nicely reproduce the measurements and show that the observed slope can be explained by eddy diffusion profiles as observed from rocket measurements.

  4. Red cell distribution width as a marker of impaired exercise tolerance in patients with chronic heart failure

    NARCIS (Netherlands)

    Van Craenenbroeck, Emeline M; Pelle, A.J.M.; Beckers, Paul J; Possemiers, Nadine M; Ramakers, Christian; Vrints, Christiaan J; Van Hoof, Viviane; Denollet, J.; Conraads, Viviane M

    2012-01-01

    AIMS: Exercise intolerance predicts mortality in patients with chronic heart failure (CHF). Recently, increased red cell distribution width (RDW) has emerged as an additional powerful predictor of poor outcome. We investigated the relationship between RDW and exercise capacity in patients with CHF.

  5. Determinants of red cell distribution width (RDW) in cardiorenal patients: RDW is not related to erythropoietin resistance.

    NARCIS (Netherlands)

    Emans, M.E.; Putten, K. van der; Rooijen, K.L. van; Kraaijenhagen, R.J.; Swinkels, D.W.; Solinge, W.W. van; Cramer, M.J.; Doevendans, P.A.; Braam, B.; Gaillard, C.A.J.M.

    2011-01-01

    BACKGROUND: Studies have shown that red cell distribution width (RDW) is related to outcome in chronic heart failure (CHF). The pathophysiological process is unknown. We studied the relationship between RDW and erythropoietin (EPO) resistance, and related factors such as erythropoietic activity, fun

  6. Determinants of Red Cell Distribution Width (RDW) in Cardiorenal Patients : RDW is Not Related to Erythropoietin Resistance

    NARCIS (Netherlands)

    Emans, Mireille E.; van der Putten, Karien; van Rooijen, Karlijn L.; Kraaijenhagen, Rob J.; Swinkels, Dorine; van Solinge, Wouter W.; Cramer, Maarten J.; Doevendans, Pieter A. F. M.; Braam, Branko; Gaillard, Carlo A. J. M.

    2011-01-01

    Background: Studies have shown that red cell distribution width (RDW) is related to outcome in chronic heart failure (CHF). The pathophysiological process is unknown. We studied the relationship between RDW and erythropoietin (EPO) resistance, and related factors such as erythropoietic activity, fun

  7. Platelet turnover in stable coronary artery disease - influence of thrombopoietin and low-grade inflammation.

    Directory of Open Access Journals (Sweden)

    Sanne Bøjet Larsen

    Full Text Available BACKGROUND: Newly formed platelets are associated with increased aggregation and adverse outcomes in patients with coronary artery disease (CAD. The mechanisms involved in the regulation of platelet turnover in patients with CAD are largely unknown. AIM: To investigate associations between platelet turnover parameters, thrombopoietin and markers of low-grade inflammation in patients with stable CAD. Furthermore, to explore the relationship between platelet turnover parameters and type 2 diabetes, prior myocardial infarction, smoking, age, gender and renal insufficiency. METHODS: We studied 581 stable CAD patients. Platelet turnover parameters (immature platelet fraction, immature platelet count, mean platelet volume, platelet distribution width and platelet large cell-ratio were determined using automated flow cytometry (Sysmex XE-2100. Furthermore, we measured thrombopoietin and evaluated low-grade inflammation by measurement of high-sensitive CRP and interleukin-6. RESULTS: We found strong associations between the immature platelet fraction, immature platelet count, mean platelet volume, platelet distribution width and platelet large cell ratio (r = 0.61-0.99, p<0.0001. Thrombopoietin levels were inversely related to all of the platelet turnover parameters (r = -0.17--0.25, p<0.0001. Moreover, thrombopoietin levels were significantly increased in patients with diabetes (p = 0.03 and in smokers (p = 0.003. Low-grade inflammation evaluated by high-sensitive CRP correlated significantly, yet weakly, with immature platelet count (r = 0.10, p = 0.03 and thrombopoietin (r = 0.16, p<0.001. Also interleukin-6 correlated with thrombopoietin (r = 0.10, p = 0.02. CONCLUSION: In stable CAD patients, thrombopoietin was inversely associated with platelet turnover parameters. Furthermore, thrombopoietin levels were increased in patients with diabetes and in smokers. However, low-grade inflammation did not seem to have a

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

    Directory of Open Access Journals (Sweden)

    Vijaya

    2014-03-01

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

  9. THE MINIMUM WIDTH OF THE ARRIVAL DIRECTION DISTRIBUTION OF ULTRA-HIGH-ENERGY COSMIC RAYS DETECTED WITH THE YAKUTSK ARRAY

    Energy Technology Data Exchange (ETDEWEB)

    Ivanov, A. A., E-mail: ivanov@ikfia.ysn.ru [Shafer Institute for Cosmophysical Research and Aeronomy, 31 Lenin Avenue, Yakutsk 677980 (Russian Federation)

    2015-05-10

    This paper presents the results of searches for anisotropy in the arrival directions of ultra-high-energy cosmic rays (CRs) detected with the Yakutsk Array during the 1974–2008 observational period as well as searches in available data from other giant extensive air shower arrays working at present. A method of analysis based on a comparison of the minimum width of distributions in equatorial coordinates is used. As a result, a hypothesis of isotropy in arrival directions is rejected at the 99.5% significance level. The observed decrease in the minimum width of the distribution can be explained by the presence of CR sources in energy intervals and sky regions according to recent indications inferred from data of the Yakutsk Array and Telescope Array experiments.

  10. A minimal width of the arrival direction distribution of ultra-high energy cosmic rays detected with the Yakutsk array

    CERN Document Server

    Ivanov, A A

    2015-01-01

    This paper presents the results of searches for anisotropy in arrival directions of ultra-high energy cosmic rays detected with the Yakutsk Array during the 1974--2008 observational period together with available data from other giant extensive air shower arrays working at present. A method of analysis based on a comparison of the minimal width of distributions in equatorial coordinates is applied. As a result, a hypothesis of isotropy in arrival directions is rejected at the $99.5\\%$ significance level. The observed decrease in the minimal width of distribution can be explained by the presence of cosmic ray sources in energy intervals and sky regions according to the recent indications inferred from data of the Yakutsk Array and Telescope Array experiments.

  11. Red Blood Cell Distribution Width, Hematology, and Serum Biochemistry in Dogs with Echocardiographically Estimated Precapillary and Postcapillary Pulmonary Arterial Hypertension

    OpenAIRE

    2016-01-01

    Background Red blood cell distribution width (RDW) is a quantitative measurement of anisocytosis. RDW has prognostic value in humans with different cardiovascular and systemic disorders, but few studies have investigated this biomarker in dogs. Objectives To compare the RDW in dogs with precapillary and postcapillary pulmonary hypertension (PH) and a control population of dogs and to correlate RDW with demographic, echocardiographic, and laboratory variables. Animals One hundred and twenty‐se...

  12. Effect of swirling flow on platelet concentration distribution in small-caliber artificial grafts and end-to-end anastomoses

    Institute of Scientific and Technical Information of China (English)

    Fan Zhan; Yu-Bo Fan; Xiao-Yan Deng

    2011-01-01

    Platelet concentration near the blood vessel wall is one of the major factors in the adhesion of platelets to the wall.In our previous studies,it was found that swirling flows could suppress platelet adhesion in small-caliber artificial grafts and end-to-end anastomoses.In order to better understand the beneficial effect of the swirling flow,we numerically analyzed the near-wall concentration distribution of platelets in a straight tube and a sudden tubular expansion tube under both swirling flow and normal flow conditions.The numerical models were created based on our previous experimental studies.The simulation results revealed that when compared with the normal flow,the swirling flow could significantly reduce the near-wall concentration of platelets in both the straight tube and the expansion tube.The present numerical study therefore indicates that the reduction in platelet adhesion under swirling flow conditions in small-caliber arterial grafts,or in end-to-end anastomoses as observed in our previous experimental study,was possibly through a mechanism of platelet transport,in which the swirling flow reduced the near-wall concentration of platelets.

  13. Screening for EDTA-dependent deviations in platelet counts and abnormalities in platelet distribution histograms in pseudothrombocytopenia.

    Science.gov (United States)

    Bartels, P C; Schoorl, M; Lombarts, A J

    1997-11-01

    Screening for pseudothrombocytopenia caused by in vitro platelet clumping has been performed in 45,000 subjects attending a general hospital. In our region, the observed prevalence of EDTA-induced pseudothrombocytopenia in blood samples with an initial platelet count below 150 x 10(9)/l was estimated to amount to 0.1%. EDTA-induced pseudothrombocytopenia was confirmed by detection of platelet aggregates by means of microscopic evaluation from the blood smear. In routine investigations, pseudothrombocytopenia could be highly suspected when the Sysmex NE 8000 showed characteristic peculiarities in the white blood cell (WBC) scattergram and histogram. Platelet aggregation is avoided in such cases by the use of citrate as an anticoagulant instead of EDTA. Pseudothrombocytopenia was detected in 46 subjects. As a screening test for pseudothrombocytopenia, increased cut-off values derived from the WBC histogram demonstrated 90% sensitivity and 100% specificity. Automated flagging for platelet clumps, deviations reflecting MPV, or PDW abnormalities revealed lower scores with respect to sensitivity.

  14. Effect of width of repair welding on stress distribution of dissimilar metal butt weld of nuclear piping

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, Won Shik; Lee, Hwee Seung; Huh, Nam Su [Seoul National Univ. of Science and Technology, Seoul (Korea, Republic of)

    2013-10-15

    In the present work, the welding residual stress due to repair welding and the stress redistribution behavior due to primary pressure are investigated via 2-dimensional non-linear finite element analyses. In particular, the effect of repair welding width on stress distribution is emphasized. Although, large tensile residual stresses are produced at the PWSCC sensitive region due to repair welding, these stresses are highly reduced due to stress redistribution caused by primary load. Based on the present finite element results, it has been revealed that the effect of width of repair welding on stress distribution is not significant. In the past few years, many numerical and experimental works have been made to assess a structural integrity of cracked components subjected to primary water stress corrosion cracking in dissimilar metal weld (DMW) using Alloys 82/182 in nuclear industries worldwide. These works include a prediction of weld residual stresses in dissimilar metal weld by either numerical or experimental works since an accurate estimation of residual stress distribution in dissimilar metal weld is the most important element for integrity assessment of components subjected to primary water stress corrosion cracking. During an actual welding process, in general, a repair welding is often performed when a defect indication is detected during post-welding inspection. It has been revealed that such a repair welding could lead to higher tensile residual stress in dissimilar metal weld, which is detrimental to the crack growth due to primary water stress corrosion cracking. Thus, the prediction of residual stress considering a repair welding is needed, and then many efforts were made on this issue. In the present work, the effect of width of repair welding on stress distribution of dissimilar metal butt weld of nuclear piping is evaluated based on the detailed 2-dimensional non-linear finite element analyses. For this purpose, the welding residual stress due to

  15. Effect of Composite Salvia Injection on Platelet Parameters in Children with Anaphylactoid Purpura

    Institute of Scientific and Technical Information of China (English)

    谢雪兰; 寇素茹; 许月红; 李朝英

    2009-01-01

    Objective:To explore the effect of composite salvia injection(CSI) on platelet parameters in children with anaphylactoid purpura(AP) and its clinical significance.Methods:One hundred and fifty children with AP were assigned to two groups,80 in Group A and 70 in Group B.They were treated,respectively,with conventional therapy only or conventional therapy combined with CSI.Their platelet parameters,including blood platelet count(BPC),mean platelet volume(MPV),platelet distribution width(PDW) and plateletcr...

  16. Influence of sea ice lead-width distribution on turbulent heat transfer between the ocean and the atmosphere

    Directory of Open Access Journals (Sweden)

    S. Marcq

    2012-02-01

    Full Text Available Leads are linear-like structures of open water within the sea ice cover that develop as the result of fracturing due to divergence or shear. Through leads, air and water come into contact and directly exchange latent and sensible heat through convective processes driven by the large temperature and moisture differences between them. In the central Arctic, leads only cover 1 to 2% of the ocean during winter, but account for more than 70% of the upward heat fluxes. Furthermore, narrow leads (several meters are more than twice as efficient at transmitting turbulent heat than larger ones (several hundreds of meters. We show that lead widths are power law distributed, P(X~X−a with a>1, down to very small spatial scales (20 m or below. This implies that the open water fraction is by far dominated by very small leads. Using two classical formulations, which provide first order turbulence closure for the fetch-dependence of heat fluxes, we find that the mean heat fluxes (sensible and latent over open water are up to 55% larger when considering the lead-width distribution obtained from a SPOT satellite image of the ice cover, compared to the situation where the open water fraction constitutes one unique large lead and the rest of the area is covered by ice, as it is usually considered in climate models at the grid scale. This difference may be even larger if we assume that the power law scaling of lead widths extends down to smaller (~1 m scales. Such estimations may be a first step towards a subgrid scale parameterization of the spatial distribution of open water for heat fluxes calculations in ocean/sea ice coupled models.

  17. Platelet lipidomic.

    Science.gov (United States)

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

    2012-01-01

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

  18. Red cell distribution width in relation to incidence of stroke and carotid atherosclerosis: a population-based cohort study.

    Directory of Open Access Journals (Sweden)

    Martin Söderholm

    Full Text Available Increased red cell distribution width (RDW has been related to poor prognosis in patients with cardiovascular disease, and is a predictor of cardiovascular mortality in the general population. The purpose of the present study was to investigate if RDW is associated with increased incidence of stroke and its subtypes in individuals from the general population.Red cell distribution width was measured in 26,879 participants (16,561 women and 10,318 men aged 45-73 years without history of coronary events or stroke, from the population-based Malmö Diet and Cancer Study. Incidences of total stroke and stroke subtypes over a mean follow-up of 15.2 years were calculated in relation to sex-specific quartiles of RDW. The presence of carotid plaque and intima-media thickness, as assessed by ultrasound, was studied in relation to RDW in a randomly selected subcohort (n = 5,309.Incidences of total stroke (n = 1,869 and cerebral infarction (n = 1,544 were both increased in individuals with high RDW. Hazard ratios (HRs in the highest compared to the lowest quartile were 1.31 for total stroke (95% confidence interval [CI]: 1.11-1.54, p for trend = 0.004 and 1.32 for cerebral infarction (95% CI: 1.10-1.58, p for trend = 0.004 after adjustment for stroke risk factors and hematological parameters. The adjusted HR for intracerebral hemorrhage (n = 230 was 1.44 (95% CI: 0.90-2.30 and the HR for subarachnoid hemorrhage (n = 75 was 0.94 (95% CI: 0.43-2.07, in the highest compared to the lowest quartile of RDW. Red cell distribution width was positively associated with intima-media thickness of the common carotid artery (p for trend = 0.011.Red cell distribution width in the highest quartile was associated with increased incidence of total stroke and cerebral infarction. There was no significant association between RDW and incidence of intracerebral or subarachnoid hemorrhage.

  19. Atmospheric velocity spectral width measurements using the statistical distribution of pulsed CO2 lidar return signal intensities

    Science.gov (United States)

    Ancellet, Gerard M.; Menzies, Robert T.; Grant, William B.

    1989-01-01

    A pulsed CO2 lidar with coherent detection has been used to measure the correlation time of backscatter from an ensemble of atmospheric aerosol particles which are illuminated by the pulsed radiation. The correlation time of the backscatter of the return signal, which is directly related to the velocity spectral width, can be used to study the velocity structure constant of atmospheric turbulence and wind shear. Various techniques for correlation time measurement are discussed, and several measurement results are presented for the technique using the information contained in the statistical distribution of a set of lidar return signal intensities.

  20. Effect of connector width on stress distribution in all ceramic fixed partial dentures (a 3D finite element study).

    Science.gov (United States)

    Mokhtarikhoee, Sepideh; Jannesari, Alireza; Behroozi, Hamid; Mokhtarikhoee, Saeedeh

    2008-01-01

    Connectors in fixed partial dentures (FPDs) are the weakest areas and responsible for failure in most cases. Optimizing the design of connectors will lead to higher strength and better performance of all-ceramic FPDs. The aim of this study was to use the finite element method in order to simulate the effect of connector width on stress distribution in all-ceramic FPDs. Three 3-dimensional finite element models for a 3-unit FPD made of IPS-Empress 2 representing a lower first molar were created and a static load of 500 N was applied axially at mid pontic area. By choosing three different widths, 3 mm, 4 mm, 5 mm for connectors, three models I,II, and III for complete assembly of teeth and connectors were created. Maximum stress occurred in the connector area in all models. Compared to model I, stress decreased 24% in model III; so the wider connector lead to lower stress values. Connectors are the most regular area for the fracture in all-ceramic FPDs because of high concentration of stress. Decreasing the width of connector raises the stress and increases the risk for fracture. Also, maximum stress in bridges is less than half of the strength of IPS-Empress2 and no failure is expected for all cases. This in vitro study of 3-unit all ceramicFPDs made with IPS-Empress2 shows that an increase in the width of connector reduces the stress concentration and improves the likelihood of long-term prognosis. Also, IPS-Empress2 can be used in posterior regions in many cases.

  1. Red blood cell distribution width is an independent predictor of mortality in patients with gram-negative bacteremia.

    Science.gov (United States)

    Ku, Nam Su; Kim, Hye-Won; Oh, Hyung Jung; Kim, Yong Chan; Kim, Min Hyung; Song, Je Eun; Oh, Dong Hyun; Ahn, Jin Young; Kim, Sun Bean; Jeong, Su Jin; Han, Sang Hoon; Kim, Chang Oh; Song, Young Goo; Kim, June Myung; Choi, Jun Yong

    2012-08-01

    Red blood cell distribution width (RDW) is known to be a predictor of severe morbidity and mortality in some chronic diseases such as congestive heart failure. However, to our knowledge, little is known about RDW as a predictor of mortality in patients with Gram-negative bacteremia, a major nosocomial cause of intra-abdominal infections, urinary tract infections, and primary bacteremia. Therefore, we investigated whether RDW is an independent predictor of mortality in patients with Gram-negative bacteremia. Clinical characteristics, laboratory parameters, and outcomes of 161 patients with Gram-negative bacteremia from November 2010 to March 2011 diagnosed at Severance Hospital, Yonsei University College of Medicine, Seoul, Korea, were retrospectively analyzed. The main outcome measure was 28-day all-cause mortality. The 28-day mortality rate was significantly higher in the increased RDW group compared with the normal RDW group (P blood cell distribution width at the onset of bacteremia was an independent predictor of mortality in patients with Gram-negative bacteremia. Also, 72-h RDW could be a predictor for all-cause mortality in patients with Gram-negative bacteremia.

  2. TO EVALUATE ANAEMIA BY ERYTHROCYTE INDICES, RED CELL DISTRIBUTION WIDTH AND HAEMOGLOBIN ELECTROPHORESIS WITH SPECIAL REFERENCE TO THALASSEMIA IN PAEDIATRIC AGE GROUP

    Directory of Open Access Journals (Sweden)

    Mahendra

    2015-02-01

    Full Text Available Anemia is not a diagnosis; it is a manifestation of an underlying disorder. Thus, even mild, asymptomatic anemia should be investigated so that the primary problem can be diagnosed and treated. Laboratory evaluation begins with a CBC, including WBC and platelet counts, RBC indices and morphology (MCV, MCH, MCHC, RBC distribution width [RDW], and examination of the peripheral smear. In many instances routine test like Hb, TLC, DLC, GBP fail to decide anemia especially in early cases and also fail to decide the type of anaemia. In such situations the RBC indices and RDW are very useful. These become abnormal even before changes in routine hemogram are appreciable. Thalassemia minor poses problems in diagnosis because GBP reveals no features of hemolysis rather it has microcytic hypochromic picture which has similarity with iron deficiency anemia. It is difficult to differentiate between two by only GBP. Several decision making rules have been proposed for differentiation. METHOD : The present study was carried out in 100 cases to evaluate anaemia in different age groups based on RBC Indices and RDW and t o evaluate sensitivity of RBC indices and RDW in diagnosis of anaemia. Cases showing positivity by various rules and RDW in favour of thalassemia minor were subjected to Hb electrophoresis for confirmation of diagnosis. RESULTS : RBC indices are more sensitive for diagnosis of microcytic hypochromic anemia, normocytic normochromic anemia and macrocytic anemia than PBS alone. RDW - CV is superior to all in use to differentiate iron deficiency anemia an d thalassemia minor having high sensitivity 87.3% and specificity 90 .5%.

  3. Terrace-width distributions of touching steps: Modification of the fermion analogy with implications for measuring step-step interactions

    Science.gov (United States)

    Sathiyanarayanan, Rajesh; Hamouda, Ajmi Bh.; Einstein, T. L.

    2009-10-01

    Using Monte Carlo simulations, we compute the terrace-width distributions (TWDs) of surfaces in which steps can touch each other, forming multiple-atomic height steps, but cannot cross (no overhangs), and so inconsistent with the standard mapping to spinless fermions. Our results show that the generalized Wigner distribution with minor modifications at small step separations, gives a very good fit for TWDs of touching steps. The interaction strength derived from the fit parameter (ϱ) indicates an effective attraction between steps. The strength of this effective attraction decreases for larger mean-step separations and decreasing step-touching energies; describable via finite-size scaling. Hence, accurate extraction of the true repulsion strength requires multiple vicinalities.

  4. Another way to view the chain conformation broadening of the line-width distribution measured in dynamic light scattering

    Institute of Scientific and Technical Information of China (English)

    吴奇; 牛爱珍

    1999-01-01

    In dynamic laser light scattering (LLS), for a given polydisperse sample, a line-width distribution G(Γ) or the translational diffusion coefficient distribution G(D) can be obtained from the measured time correlation function. For rigid colloid particles, G(Γ) can be directly related to the hydrodynamic size distribution. However, for flexible polymer chains, G(Γ) depends not only on the chain length distribution, but also on the relaxation of the chain conformation; that is, even for a monodisperse polymer sample there still exists a chain conformation distribution. If the time scale of the chain conformation relaxation is comparable to that of the translational diffusion, such as in the case of a very long polymer chain, the conformation relaxation might lead to an additional broadening in G (Γ). This "conformation broadening" has been directly observed for the first time by comparing two G(Γ) s obtained from a poly(N-isopropyl-acrylamide) solution at~25℃ and~32℃ at which the solution is ther

  5. A comparison of the fibrinogen receptor distribution on adherent platelets using both soluble fibrinogen and fibrinogen immobilized on gold beads.

    Science.gov (United States)

    Estry, D W; Mattson, J C; Mahoney, G J; Oesterle, J R

    1991-04-01

    The distribution of fibrinogen receptors was determined on the surface of adherent platelets using both direct labeling with the ligand fibrinogen which was immobilized on gold particles (Fg-Au) and indirect immunogold (Ig-Au) labeling of bound soluble fibrinogen identified with a rabbit polyclonal anti-fibrinogen antibody. Two distinctly different patterns of labeling were obtained and appeared to depend on whether solid phase fibrinogen (Fg-Au) or soluble phase released fibrinogen were bound to the membrane receptor. The membrane-bound Fg-Au reorganized in patterns that closely mimicked the organization of the underlying cytoskeleton. In approximately 18% of the adherent platelets, Fg-Au was seen in channels or vesicle-like structures lying deep to the platelet surface suggesting internalization into the open canalicular system and/or endocytosis. The labeling pattern obtained when identifying the location of membrane-bound soluble released fibrinogen by Ig-Au was diffuse and lacked the organizational patterns characteristic of Fg-Au. Unlike the Fg-Au probe, early dendritic platelets were heavily labeled by the soluble phase fibrinogen using the Ig-Au technique. Although the label covered the entire exposed platelet membrane in fully spread platelets, labeling over the peripheral web was more dense than that over the intermediate or granulomere zone. The diffuse organization and heavier peripheral distributional pattern of the glycoprotein IIb-IIIa (GP IIb-IIIa) receptor in fixed, adherent platelets, was also seen with the GP IIb-IIIa receptor-specific antibody AP-2. The binding of both the Fg-Au and Ig-Au were inhibited using the tetrapeptide Arg-Gly-Asp-Ser (RGDS) (93% and 98% inhibition, respectively), AP-2 (98% and 97%, respectively) and platelets from patients with Glanzmann's thrombasthenia (GT) (99% and 98%, respectively). The data presented provides the first report that receptor reorganization, following binding of fibrinogen, appears to be related to

  6. Quantification of the distribution of /sup 111/In-labelled platelets in organs

    Energy Technology Data Exchange (ETDEWEB)

    van Reenen, O.; Loetter, M.G.; Heyns, A.P.; de Kock, F.; Herbst, C.; Kotze, H.; Pieters, H.; Minnaar, P.C.; Badenhorst, P.N.

    1982-02-01

    A simple and practical approach to the in vivo quantification of /sup 111/indium-oxine labelled blood platelets with a scintillation camera and computer assisted imaging system was evaluated. Radioactivity of the 172 and 247 keV energies was measured in a phantom at various source distances from the collimator and the accuracy of anterior and posterior mode measurements compared with that of the geometrical mean (GM) method, with and without correction for Compton scatter (CS). Organ radioactivity, expressed as a percentage of whole body radioactivity, was determined in vivo in five baboons and the accuracy of the methods verified by post mortem quantification in the animals. Measurement in the anterior mode significantly overestimates hepatic and underestimates splenic radioactivity; posterior mode quantification reverses these results. Correction with the GM method made the accuracy and reproducibility very acceptable. Further correction for anterior-posterior attenuation and/or CS did not improve results materially. The GM method could readily be applied in five human subjects. This study shows that the GM method is an accurate and practical method for the in vivo quantification of organ and regional distribution of /sup 111/In-labelled platelets.

  7. Distributed seeding for narrow-line width hard x-ray free-electron lasers

    Energy Technology Data Exchange (ETDEWEB)

    Nguyen, Dinh Cong [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Anisimov, Petr Mikhaylovich [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Buechler, Cynthia Eileen [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Lewellen, IV, John W. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Marksteiner, Quinn R. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-09-09

    We describe a new FEL line-narrowing technique called distributed seeding (DS), using Si(111) Bragg crystal monochromators to enhance the spectral brightness of the MaRIE hard X-ray freeelectron laser. DS differs from self-seeding in three important aspects. First, DS relies on spectral filtering of the radiation at multiple locations along the undulator, with a monochromator located every few power gain lengths. Second, DS performs filtering early in the exponential gain region before SASE spikes start to appear in the radiation longitudinal profile. Third, DS provides the option to select a wavelength longer than the peak of the SASE gain curve, which leads to improved spectral contrast of the seeded FEL over the SASE background. Timedependent Genesis simulations show the power-vs-z growth curves for DS exhibit behaviors of a seeded FEL amplifier, such as exponential growth region immediately after the filters. Of the seeding approaches considered, the two-stage DS spectra produce the highest contrast of seeded FEL over the SASE background and that the three-stage DS provides the narrowest linewidth with a relative spectral FWHM of 8 X 10-5 .

  8. Exercise-induced changes in the in vivo distribution of /sup 111/In-labelled platelets

    Energy Technology Data Exchange (ETDEWEB)

    Schmidt, K.G.; Waever Rasmussen, J. (Department of Radiophysics, Odense University Hospital, Odense, Denmark)

    1984-01-01

    In order to throw some light on the mechanisms underlying exercise-induced thrombocytosis, we investigated 15 healthy persons subjected to short-term vigorous pedalling on a bicycle ergometer 1 d after injection of autologous /sup 111/In-labelled platelets. Scintigraphic studies during the post-excercise period showed the spleen to be the major platelet-releasing organ. There was, however, a considerable interindividual variability manifested as signs of a contributing platelet release from the lungs in some cases and of deposition of a surplus of released platelets in the liver of others. Our results also seem to be compatible with the existence of an intravascular marginal platelet pool.

  9. Impact Of The Pulse Width Modulation On The Temperature Distribution In The Armature Of A Solenoid Valve

    Directory of Open Access Journals (Sweden)

    Goraj R.

    2015-12-01

    Full Text Available In order to estimate the inductive power set in the armature of the high-speed solenoid valve (HSV during the open loop control (OLC using pulse width modulation (PWM an analytical explicit formula has been derived. The simplifications taken both in the geometry and in the physical behavior of the HSV were described. The inductive power was calculated for different boundary conditions and shown as a function of the frequency of the coil current. The power set in the armature was used as an input to the thermal calculation. The thermal calculation had an objective to estimate the time dependent temperature distribution in the armature of the HSV. All the derivation steps were presented and the influence of different boundary conditions was shown and discussed. The increase of the temperature during the heating with inductive power has been evaluated both in the core and on the side surface of the HSV.

  10. Impact Of The Pulse Width Modulation On The Temperature Distribution In The Armature Of A Solenoid Valve

    Science.gov (United States)

    Goraj, R.

    2015-12-01

    In order to estimate the inductive power set in the armature of the high-speed solenoid valve (HSV) during the open loop control (OLC) using pulse width modulation (PWM) an analytical explicit formula has been derived. The simplifications taken both in the geometry and in the physical behavior of the HSV were described. The inductive power was calculated for different boundary conditions and shown as a function of the frequency of the coil current. The power set in the armature was used as an input to the thermal calculation. The thermal calculation had an objective to estimate the time dependent temperature distribution in the armature of the HSV. All the derivation steps were presented and the influence of different boundary conditions was shown and discussed. The increase of the temperature during the heating with inductive power has been evaluated both in the core and on the side surface of the HSV.

  11. The platelet indices in pediatric patients with acute appendicitis

    Directory of Open Access Journals (Sweden)

    Yunus Yilmaz

    2015-06-01

    Full Text Available Background: The diagnosis of Acute Appendicitis (AA remains a problem in pediatric population. It has been suggested that Mean Platelet Volume (MPV is lower in the patients with AA. The purpose of this study was to investigate the diagnostic value of platelet indices in pediatric AA cases. Methods: A retrospective case-controlled study was designed: 224 subjects were included in this study. All patients had been operated on in division of pediatric surgery at the Kars Government Hospital with the preliminary diagnosis of AA. 204 and 20 of these patients were pathologically diagnosed as AA (group 1 and normal appendix vermiformis (group 2, respectively. Platelet indices had been studied in the biochemistry laboratory of the hospital, before the surgery. Results: In group 1, platelet count, mean platelet volume, plateletcrit and platelet distribution width were 305 +/- 94x103/ and micro;L; 7.37 +/- 0.90 fL; 0,220 +/- 0.057 % and 16.3 +/- 0.5%, respectively. In group 2, platelet count, mean platelet volume, plateletcrit and platelet distribution width were 283 +/- 85 103/ and micro;L; 7.60 +/- 1.24 fL; 0.208 +/- 0.045 % and 16.4 +/- 0.7%, respectively. There was no statistically significant difference between the groups studied with regard to platelet indices (P>0.05. Conclusions: Our study showed that platelet indices have no diagnostic value in the diagnosis of AA at pediatric age group. [Int J Res Med Sci 2015; 3(6.000: 1388-1391

  12. Red Cell Distribution Width

    Science.gov (United States)

    ... used to diagnose: Other blood disorders such as thalassemia , an inherited disease that can cause severe anemia ... cold hands and feet A family history of thalassemia, sickle cell anemia or other inherited blood disorder ...

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

    Science.gov (United States)

    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

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

    Science.gov (United States)

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

    2016-01-01

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

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

    Directory of Open Access Journals (Sweden)

    Abbas Mirvakili

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

  16. [HPA distribution characteristics of platelet donor population in Mudanjiang area of China and establishment of its database].

    Science.gov (United States)

    Liu, Bing-Xian; Gao, Guang-Ping; Wang, Dan; Zhang, Yan; Yu, Xiu-Qing; Xia, Dong-Mei; Zhou, Rui-Hua; Zhang, Hua; Ma, Qiang; Liu, Jie

    2012-06-01

    This study was aimed to explore the distribution characteristics of the human platelet antigen (HPA) gene of human platelet donors and its polymorphism in Mudanjiang area of Heilongjiang Province in China, to determine platelet antigen system with clinical significance by judging the rate of incompatibility of HPA, as well as to establish a database of donors' HPA. The genotyping of 154 unrelated platelet donors was performed by means of PCR-SSP. The frequencies of gene and genotype were calculated and compared with that in other areas. The results showed that the genes 1a-17a of HPA-a were all expressed in the 154 healthy and unrelated platelet donors. Only genes 1b, 2b, 3b, 5b, 6b and 15b of HPA-b were expressed while genes 4b, 7b-14b, 16b were not expressed. Among the genotypes, aa homozygosity was predominant and HPA15 had the greatest heterozygosity, while HPA3 had lower heterozygosity. There were 23 combined types of HPA, 5 of them had a rate higher than 10%, and the frequencies of the other 18 were lower than 8%. HPA genotype frequencies showed a good consistency to Hardy-Weinberg equilibrium. It is concluded that the distribution of the allele polymorphism of HPA1-HPA17 in Mudanjiang area has its own characteristics, compared with other areas and some countries, the local HPA genotype database of platelet donors is established in Mudanjiang area, which can provide the matching donors for clinical use with immunological significance.

  17. Changes in platelet parameters in leukocytosis.

    Science.gov (United States)

    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.

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

    Science.gov (United States)

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

    2012-01-01

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

  19. Evaluation of the effect of red cell distribution width on the development of acute renal failure in patients with sepsis

    Directory of Open Access Journals (Sweden)

    Ali Veysel Kara

    2017-06-01

    Full Text Available Objective: Acute kidney injury (AKI is an important clinical entity that is known to increase mortality in patients with sepsis. Erythrocyte maturation and proliferation are inhibited by pro-inflammatory cytokines; these cytokines exert effects on red cell distribution width (RDW well. Based on this knowledge; our aim in this study was to evaluate the impact of RDW on acute kidney injury in patients with sepsis. Methods: 120 patients diagnosed with sepsis and admitted to intesive care unit (ICU and treated between 2009-2013 were retrospectively evaluated. Patients were divided into two groups as follows: group 1 (RDW≥16.8 and group 2 (RDW<16.8. Multiple logistic regression analysis was used to determine the association between RDW and AKI and mortality. Results: There was a statistically significant relationship between AKI and RDW (p<0.001, OR=11.52 but there were no statistically significant relationship between AKI and sex, age, serum lactate levels as well as SOFA score. Also, there were statistically significant relationship between mortality and RDW (p=0.044, OR=5, serum lactate levels (p=0.030 and SOFA score (p<0.001. RDW was found associated with both AKI and mortality. Conclusions: Results suggest that RDW is an important parameter for predicting development of AKI and mortality in ICU patients with sepsis.

  20. Red cell distribution width and risk of cardiovascular mortality: Insights from National Health and Nutrition Examination Survey (NHANES)-III.

    Science.gov (United States)

    Shah, Neeraj; Pahuja, Mohit; Pant, Sadip; Handa, Aman; Agarwal, Vratika; Patel, Nileshkumar; Dusaj, Raman

    2017-04-01

    Red cell distribution width (RDW) has been linked to cardiovascular disease. We sought to determine whether addition of RDW improved the Framingham risk score (FRS) model to predict cardiovascular mortality in a healthy US cohort. We performed a post-hoc analysis of the National Health and Nutritional Examination Survey-III (1988-94) cohort, including non-anemic subjects aged 30-79years. Primary endpoint was death from coronary heart disease (CHD). We divided the cohort into three risk categories: 20%. RDW>14.5 was considered high. Kaplan-Meier survival curves and Cox proportional hazards models were created. Discrimination, calibration and reclassification were used to assess the value of addition of RDW to the FRS model. We included 7005 subjects with a mean follow up of 14.1years. Overall, there were 233 (3.3%) CHD deaths; 27 (8.2%) in subjects with RDW>14.5 compared to 206 (3.1%) in subjects with RDW≤14.5 (prisk NRI of 9.6% (p=0.011). Absolute integrated discrimination index (IDI) was 0.004 (p=0.02), with relative IDI of 10.4%. Our study demonstrates that RDW is a promising biomarker which improves prediction of cardiovascular mortality over and above traditional cardiovascular risk factors. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. Lead detection in Arctic sea ice from CryoSat-2: quality assessment, lead area fraction and width distribution

    Directory of Open Access Journals (Sweden)

    A. Wernecke

    2015-03-01

    Full Text Available Leads cover only a small fraction of the Arctic sea ice but they have a dominant effect on the turbulent exchange between the ocean and the atmosphere. A supervised classification of CryoSat-2 measurements is performed by a combination with visual MODIS scenes. For several parameters thresholds are optimized and tested in order to reproduce this prior classification. The maximum power of the waveform shows the best classification properties amongst them, including the Pulse Peakiness. With the same correct lead detection rates as of published classifiers, the amount of ice being detected as lead can be reduced by up to 40%. Lead area fraction estimates based on CryoSat-2 show a major fracturing event in the Beaufort Sea in 2013. The resulting Arctic wide lead width distribution follows a power law with an exponent of 2.47 ± 0.04 for the winter seasons from 2011 to 2014, confirming and complementing a regional study based on a high resolution SPOT image.

  2. Haematological, biochemical and inflammatory parameters in inactive Behçet's disease. Its association with red blood cell distribution width.

    Science.gov (United States)

    Vayá, Amparo; Rivera, Leonor; Todolí, José; Hernandez, Jose Luis; Laiz, Begoña; Ricart, José M

    2014-01-01

    Red blood cell distribution width (RDW) has been shown to be associated with disease activity in several inflammatory disorders. However only one study to show this has been conducted in patients with Behçet's disease (BD). The aim of the present study was to analyse the association of RDW with BD and its main complications; i.e.; thrombosis and posterior uveitis. A second aim was to analyse the possible correlation between RDW and both haematological and inflammatory parameters. Eighty-nine patients with BD (48 males/41 females) and 94 controls (49 males/45 females) were included in the study. Patients were in an inactive phase of the disease, showing only minimum activity. RDW was statistically higher in patients than in controls (14.02 ± 1.32 vs. 13.15 ± 0.75; p 0.05). RDW correlated negatively with haemoglobin, MCH and MCHC (p 0.05). The multivariate regression analysis revealed that haemoglobin and homocysteine were independent predictors of RDW (beta coefficient: -0.310; p = 0.003, beta coefficient: 0.379; p 14 was associated with neither thrombosis nor uveitis (p = 0.935; p = 0.553, respectively). Our results indicate that BD patients show increased RDW when compared with controls. This increase seems to be related with haematimetric indices and with homocysteine levels. Lack of correlation with inflammatory markers may be due to the fact that patients were in an inactive phase of the disease.

  3. The Prognostic Role of Red Blood Cell Distribution Width in Coronary Artery Disease: A Review of the Pathophysiology

    Directory of Open Access Journals (Sweden)

    Kamil Bujak

    2015-01-01

    Full Text Available Red blood cell distribution width (RDW is a measure of red blood cell volume variations (anisocytosis and is reported as part of a standard complete blood count. In recent years, numerous studies have noted the importance of RDW as a predictor of poor clinical outcomes in the settings of various diseases, including coronary artery disease (CAD. In this paper, we discuss the prognostic value of RDW in CAD and describe the pathophysiological connection between RDW and acute coronary syndrome. In our opinion, the negative prognostic effects of elevated RDW levels may be attributed to the adverse effects of independent risk factors such as inflammation, oxidative stress, and vitamin D3 and iron deficiency on bone marrow function (erythropoiesis. Elevated RDW values may reflect the intensity of these phenomena and their unfavorable impacts on bone marrow erythropoiesis. Furthermore, decreased red blood cell deformability among patients with higher RDW values impairs blood flow through the microcirculation, resulting in the diminution of oxygen supply at the tissue level, particularly among patients suffering from myocardial infarction treated with urgent revascularization.

  4. The Prognostic Role of Red Blood Cell Distribution Width in Coronary Artery Disease: A Review of the Pathophysiology

    Science.gov (United States)

    Bujak, Kamil; Wasilewski, Jarosław; Osadnik, Tadeusz; Jonczyk, Sandra; Kołodziejska, Aleksandra; Gierlotka, Marek; Gąsior, Mariusz

    2015-01-01

    Red blood cell distribution width (RDW) is a measure of red blood cell volume variations (anisocytosis) and is reported as part of a standard complete blood count. In recent years, numerous studies have noted the importance of RDW as a predictor of poor clinical outcomes in the settings of various diseases, including coronary artery disease (CAD). In this paper, we discuss the prognostic value of RDW in CAD and describe the pathophysiological connection between RDW and acute coronary syndrome. In our opinion, the negative prognostic effects of elevated RDW levels may be attributed to the adverse effects of independent risk factors such as inflammation, oxidative stress, and vitamin D3 and iron deficiency on bone marrow function (erythropoiesis). Elevated RDW values may reflect the intensity of these phenomena and their unfavorable impacts on bone marrow erythropoiesis. Furthermore, decreased red blood cell deformability among patients with higher RDW values impairs blood flow through the microcirculation, resulting in the diminution of oxygen supply at the tissue level, particularly among patients suffering from myocardial infarction treated with urgent revascularization. PMID:26379362

  5. Reduction in mean platelet volume in children with acute bronchiolitis.

    Science.gov (United States)

    Ergül, Ayşe Betül; Torun, Yasemin Altuner; Uytun, Salih; Aslaner, Hümeyra; Kısaaslan, Ayşenur Paç; Şerbetçi, Mahmut Can

    2016-03-01

    Platelets which are known to play a role in inflamation change their shapes when they are activated and this change is reflected in mean platelet volume and platelet distribution width values. Therefore, the mean platelet volume and platelet distribution width values are considered to be beneficial parameters for the diagnosis and treatment of many inflammatory diseases. The aim of the study was to evaluate platelet volume indices in children with acute bronchiolitis. A total of 514 infants who were below the age of 2 years old were evaluated in this study. Three hundred thirteen of these infants were diagnosed with acute bronchiolitis patients and 201 were healthy children. The patients were separated into four groups as mild, moderate, severe bronchiolitis and the control patient group. The groups were evaluated in terms of significant differences in the values of mean platelet volume and platelet distribution width. A p value of <0.05 was considered statistically significant for all results. The mean platelet volume was found to be 6.8±0.6 fL in the patients with mild bronchiolitis attack, 6.7±0.6 fL in the patients with moderate bronchiolitis attack, 6.5±0.5 fL in the patients with severe bronchiolitis attack and 7.3±1.1 fL in the control group. The mean platalet volume was statistically significantly lower in the mild, moderate and severe bronchiolitis attack groups compared to the control group (p=0.000). The platelet distribution width was found to be 17.2%±0.83 in the mild bronchiolitis attack group, 17.1%±0.96 in the moderate bronchiolitis attack group, 17.3%±0.87 in the severe bronchiolitis attack group and 16.9±1.6% in the control patient group. This difference was not statistically significant (p=0.159). The platelet count was statistically significantly higher in the mild, moderate and severe bronchiolitis attack groups compared to the control group (p=0.000). The mean platalet volume is decreased in patients with acute bronchiolitis. It is not

  6. Distribution of Platelet-rich Plasma after Ultrasound-Guided Injection for Chronic Elbow Tendinopathies

    Science.gov (United States)

    Park, Gi-Young; Kwon, Dong Rak; Cho, Hee Kyung; Park, Jinyoung; Park, Jung Hyun

    2017-01-01

    Characteristics of the spreads of platelet-rich plasma (PRP) are not widely known despite commonly use. This study aims to evaluate whether PRP stays within the injected area by using ultrasonography, to improve understanding of the spreads of intratendinous injected PRP. Thirty-nine patients (15 males, 24 females; mean age, 49.3 years), who had symptoms on their elbows (> 6 months) and diagnosed as lateral (25 elbows) or medial (14 elbows) tendinopathies of elbow, were included. The severity of tendon pathology was assessed by ultrasonography as tear or no tear. Immediately after ultrasound-guided PRP injection, ultrasound images were evaluated to assess the area of PRP distribution, which was defined as the presence of fluid or microbubbles. Ultrasound revealed that 13 elbows had tendon tear and 26 had no tear, respectively. Post-injection ultrasound confirmed the injected PRP was within the tendon in all cases. The mean distance of distribution from the injection site was 12.6 mm (5.0–26.0 mm). There was no difference in the distance of PRP distribution between tendon tear and no tear. Injected PRP spread to soft tissue outside the tendon in 20 of 39 cases. Intra-articular extension of PRP was observed in 5 cases. Although PRP remained intratendinous after the injection in all cases, some portion tended to spread outside from the injection site in a short space of time. Postinjection ultrasonographic imaging has a value for observing the spreading patterns of intratendinous PRP injection. Key points This study aims to evaluate whether PRP stays within the injected area by using ultrasonography, to improve understanding of the spreads of intratendinous injected PRP. Although PRP remained intratendinous after the injection in all cases, some portion tended to spread outside from the injection site in a short space of time. PMID:28344444

  7. Distribution of Platelet-rich Plasma after Ultrasound-Guided Injection for Chronic Elbow Tendinopathies

    Directory of Open Access Journals (Sweden)

    Gi-Young Park, Dong Rak Kwon, Hee Kyung Cho, Jinyoung Park, Jung Hyun Park

    2017-03-01

    Full Text Available Characteristics of the spreads of platelet-rich plasma (PRP are not widely known despite commonly use. This study aims to evaluate whether PRP stays within the injected area by using ultrasonography, to improve understanding of the spreads of intratendinous injected PRP. Thirty-nine patients (15 males, 24 females; mean age, 49.3 years, who had symptoms on their elbows (> 6 months and diagnosed as lateral (25 elbows or medial (14 elbows tendinopathies of elbow, were included. The severity of tendon pathology was assessed by ultrasonography as tear or no tear. Immediately after ultrasound-guided PRP injection, ultrasound images were evaluated to assess the area of PRP distribution, which was defined as the presence of fluid or microbubbles. Ultrasound revealed that 13 elbows had tendon tear and 26 had no tear, respectively. Post-injection ultrasound confirmed the injected PRP was within the tendon in all cases. The mean distance of distribution from the injection site was 12.6 mm (5.0–26.0 mm. There was no difference in the distance of PRP distribution between tendon tear and no tear. Injected PRP spread to soft tissue outside the tendon in 20 of 39 cases. Intra-articular extension of PRP was observed in 5 cases. Although PRP remained intratendinous after the injection in all cases, some portion tended to spread outside from the injection site in a short space of time. Postinjection ultrasonographic imaging has a value for observing the spreading patterns of intratendinous PRP injection.

  8. An overall and dose-response meta-analysis of red blood cell distribution width and CVD outcomes

    Science.gov (United States)

    Hou, Haifeng; Sun, Tao; Li, Cheng; Li, Yuanmin; Guo, Zheng; Wang, Wei; Li, Dong

    2017-01-01

    Red blood cell distribution width (RDW) is the coefficient of variation of red blood cell size, considered to be associated with cardiovascular disease (CVD). This study aimed to comprehensively synthesize previous studies on RDW and CVD outcomes through an overall and dose-response meta-analysis. PubMed, Embase and Web of Science were searched systematically for English and Chinese language publications up to November 30, 2015. We extracted data from publications matching our inclusion criteria for calculating pooled hazard ratio (HR), which was used to assess prognostic impact of RDW on CVD. Twenty-seven articles, consisting of 28 studies and 102,689 participants (mean age 63.9 years, 63,703 males/36,846 females, 2,140 gender-unmentioned subjects) were included in the present meta-analysis. The pooled HRs are 1.12 (95% CI = 1.09–1.15) for the association of all-cause mortality (ACM) per 1% increase of RDW, 1.12(95% CI = 1.08–1.17) for major adverse cardiac events (MACEs) per 1% increase of RDW. A dose-response curve relating RDW increase to its effect on CVD outcomes was established (pcurve ACM (pooled HR = 1.03, 95% CI = 1.02–1.04) and MACEs (pooled HR = 1.04, 95% CI = 1.01–1.06). This study indicates RDW may be a prognostic indicator for CVD outcomes. PMID:28233844

  9. The clinical significance of changes in red blood cell distribution width in patients with community-acquired pneumonia

    Science.gov (United States)

    Lee, Sang-Min; Lee, Jae Hyuk; Kim, Kyuseok; Jo, You Hwan; Lee, Jungyoup; Kim, Joonghee; Hwang, Ji Eun; Ko, Young Sang; Ha, Chulmin; Jang, Sujin; Park, Hyunmi

    2016-01-01

    Objective Red cell distribution width (RDW) is associated with mortality in patients with community-acquired pneumonia (CAP). However, little is known about the effect of changes in RDW during treatment on mortality. Thus, the objective of this study was to evaluate the association between RDW changes and mortality in hospitalized patients with CAP. Methods Retrospective analyses were performed using medical records of patients hospitalized for CAP from April 2008 to February 2014. The abstracted laboratory values included RDW (from days one to four), clinical variables, and pneumonia severity index (PSI) scores. The ΔRDWn-1 was defined as the change in RDW calculated as: (RDWday1-RDWday-n)/RDWday1×100 (%), where ‘day n’ refers to hospital day. Results During the study period, a total of 1,069 patients were hospitalized for CAP. The 30-day mortality was 100/1,069 (9.4%). The median RDW at baseline was 14.1% (range, 11.1 to 30.2) and differed significantly between survivors and non-survivors (P<0.05). There were 470 patients with available serial RDW data (30-day mortality 58/470 [12.3%]). Of those, age, PSI score, blood urea nitrogen level, total protein concentration, albumin level, RDW at day 1, and the ΔRDW4-1 differed significantly between survivors and non-survivors. Multivariate Cox regression analysis showed that the significance of the relationship between ΔRDW4-1 and 30-day mortality risk remained after adjusting for age, PSI score, RDW at day 1, total protein concentration, and initial albumin level. Conclusion RDW change from day 1 to day 4 was an independent predictor of mortality in patients with CAP.

  10. The role of neutrophil-lymphocyte ratio and red blood cell distribution width in the classification of febrile seizures.

    Science.gov (United States)

    Yigit, Y; Yilmaz, S; Akdogan, A; Halhalli, H C; Ozbek, A E; Gencer, E G

    2017-02-01

    Most febrile seizures occur outside of hospitals, and in most cases, information about the characteristics of the seizures is obtained from the parents. This makes it difficult to differentiate between simple and complex seizures. The aim of this study is to evaluate the significance of the Neutrophil-Lymphocyte Ratio (NLR) and the red blood cell (erythrocyte) distribution width (RDW) in distinguishing between simple and complex febrile seizures. The files of 142 patients between the ages of 6 months and 5 years who were admitted to the Emergency Department with the diagnosis of first febrile seizure were reviewed retrospectively. Complete blood count and C-reactive protein (CRP) parameters obtained from the venous blood samples collected from the patients at admission were evaluated. The average values of NLR for simple and complex seizure groups were 2.38 ± 1.60 and 3.42 ± 1.77 respectively, and the difference was statistically significant (p seizure groups were 16.15 ± 1.37 and 16.27 ± 1.53, respectively; the difference was not significant (p = 0.631). We used receiver operating characteristic (ROC) analysis and chose a cutoff value of 2.315 for the NLR, and we found that the sensitivity and specificity were 62.7% and 53.8%, respectively (area under the curve [AUC]: 0.665, p = 0.001, confidence interval [CI] 0.573-0.756). We suggest that NLR may provide clinicians with an insight into differentiating between simple and complex febrile seizures; however, it does not produce a clear-cut distinction. We found that the RDW ratio is not useful in this differentiation.

  11. Incremental predictive value of red cell distribution width for 12-month clinical outcome after acute myocardial infarction.

    Science.gov (United States)

    Lee, Jang Hoon; Yang, Dong Heon; Jang, Se Yong; Choi, Won Suk; Kim, Kyun Hee; Lee, Won Kee; Bae, Myung Hwan; Park, Hun Sik; Cho, Yongkeun; Chae, Shung Chull

    2013-06-01

    The incremental predictive value of red cell distribution width (RDW) for major adverse cardiac events (MACEs) has not been fully investigated in patients with acute myocardial infarction (AMI). The aim of this study was to determine the incremental value of RDW to the established risk factors in predicting clinical outcomes after AMI. Between November 2005 and January 2010, 1596 patients with AMI (1070 male; mean age, 64.5 ± 11.9 years) were analyzed in this study. Baseline levels of RDW were measured at the time of admission. The 12-month MACEs were defined as death and nonfatal MI. The RDW levels were significantly higher in patients with 12-month MACEs (13.8 ± 1.3% vs 13.3 ± 1.2%, P Adding RDW to established risk factors and hemoglobin levels significantly improved prediction for 12-month MACEs, as shown by the net reclassification improvement (0.297; P = 0.012) and integrated discrimination improvement (0.0143; P = 0.042). The likelihood ratio test showed that RDW added incremental predictive value to the combination of hemoglobin and established risk factors (P = 0.005). Patients were categorized into 4 groups according to quartiles of RDW at baseline. Adjusted HRs for 12-month MACEs were 1 (RDW ≤12.6%, reference), 4.24 (RDW 12.7%-13.1%, P = 0.01), 4.36 (RDW 13.2%-13.9%, P = 0.008), and 6.18 (RDW 13.2%-13.9%, P = 0.001), respectively. In post-myocardial infarction patients, baseline RDW levels at admission could provide incremental predictive value to established risk factors for predicting 12-month MACEs. © 2013 Wiley Periodicals, Inc.

  12. An overall and dose-response meta-analysis of red blood cell distribution width and CVD outcomes.

    Science.gov (United States)

    Hou, Haifeng; Sun, Tao; Li, Cheng; Li, Yuanmin; Guo, Zheng; Wang, Wei; Li, Dong

    2017-02-24

    Red blood cell distribution width (RDW) is the coefficient of variation of red blood cell size, considered to be associated with cardiovascular disease (CVD). This study aimed to comprehensively synthesize previous studies on RDW and CVD outcomes through an overall and dose-response meta-analysis. PubMed, Embase and Web of Science were searched systematically for English and Chinese language publications up to November 30, 2015. We extracted data from publications matching our inclusion criteria for calculating pooled hazard ratio (HR), which was used to assess prognostic impact of RDW on CVD. Twenty-seven articles, consisting of 28 studies and 102,689 participants (mean age 63.9 years, 63,703 males/36,846 females, 2,140 gender-unmentioned subjects) were included in the present meta-analysis. The pooled HRs are 1.12 (95% CI = 1.09-1.15) for the association of all-cause mortality (ACM) per 1% increase of RDW, 1.12(95% CI = 1.08-1.17) for major adverse cardiac events (MACEs) per 1% increase of RDW. A dose-response curve relating RDW increase to its effect on CVD outcomes was established (pcurve < 0.001). For every 1-unit increase of RDW, there is an increased risk of occurrence of ACM (pooled HR = 1.03, 95% CI = 1.02-1.04) and MACEs (pooled HR = 1.04, 95% CI = 1.01-1.06). This study indicates RDW may be a prognostic indicator for CVD outcomes.

  13. COMPARISON OF RED CELL DISTRIBUTION WIDTH WITH SOFA SCORE AS A PROGNOSTIC MARKER OF SEPSIS IN ELDERLY PATIENTS

    Directory of Open Access Journals (Sweden)

    Shaikh Mohammed Aslam

    2015-12-01

    Full Text Available BACKGROUND Severe sepsis and septic shock are increasing in incidence and contributing significantly to mortality. The prediction of outcome for elderly patients with sepsis may facilitate more aggressive interventions. The SOFA score is a scoring system used to quantify the severity of the patient’s illness based on the degree of organ dysfunction. Various biomarkers are being evaluated for early diagnosis of sepsis. RDW is one of them, which have been shown to predict mortality and morbidity of sepsis. Hence, this study is being done to compare RDW with SOFA score as prognostic marker of sepsis in elderly patients. AIM To compare red cell distribution width with SOFA score as a prognostic marker of sepsis in elderly patients. METHODS A total of 93 elderly patients in sepsis who were admitted to Intensive Care Unit of M. S. Ramaiah Hospitals between October 2013 and September 2015 were included in the study. ROC (Receiver Operating Curve was used to determine the optimal cut-off point for RDW for predicting mortality. ROC of RDW was compared with ROC of SOFA score. RESULTS Mean age of the patients was 70.72±8.02 and most of the patients were in the age group of 61–70yrs. (53.8%. 52(55.9% patients were males and 41(44.1% patients were females. Bronchopneumonia (34.4% and urosepsis (30.1% were the most common causes of sepsis; 61.3% of the patients had SOFA score in the range of 5–10. Mean SOFA score was 7.87097±3.22769. Mean RDW was 14.247±2.1151. CONCLUSION RDW had a sensitivity of 81.6%, specificity of 77.3%, positive predictive value of 80%, and negative predictive value of 79.1% with a cut-off value of 13.75% in predicting mortality in elderly patients in sepsis.

  14. Application of a frequency distribution method for determining instars of the beet armyworm (Lepidoptera: Noctuidae) from widths of cast head capsules

    Science.gov (United States)

    Y. Chen; S. J. Seybold

    2013-01-01

    Instar determination of field-collected insect larvae has generally been based on the analysis of head capsule width frequency distributions or bivariate plotting, but few studies have tested the validity of such methods. We used head capsules from exuviae of known instars of the beet armyworm, Spodoptera exigua (Hübner) (Lepidoptera: Noctuidae),...

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

    Energy Technology Data Exchange (ETDEWEB)

    Schneider, M.D.; Miller, J.K.; White, P.K.; Ramsey, N.

    1983-05-01

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

  16. Information Width

    CERN Document Server

    Ratsaby, Joel

    2008-01-01

    Kolmogorov argued that the concept of information exists also in problems with no underlying stochastic model (as Shannon's information representation) for instance, the information contained in an algorithm or in the genome. He introduced a combinatorial notion of entropy and information $I(x:\\sy)$ conveyed by a binary string $x$ about the unknown value of a variable $\\sy$. The current paper poses the following questions: what is the relationship between the information conveyed by $x$ about $\\sy$ to the description complexity of $x$ ? is there a notion of cost of information ? are there limits on how efficient $x$ conveys information ? To answer these questions Kolmogorov's definition is extended and a new concept termed {\\em information width} which is similar to $n$-widths in approximation theory is introduced. Information of any input source, e.g., sample-based, general side-information or a hybrid of both can be evaluated by a single common formula. An application to the space of binary functions is con...

  17. Evaluation of the diagnostic performance of platelet-derived indices for the differential diagnosis of thrombocytopenia in pediatrics

    Directory of Open Access Journals (Sweden)

    Nelson Hernando Aponte-Barrios

    2014-10-01

    Full Text Available Background. Platelet-derived indices have a well-established correlation with the differential diagnosis of thrombocytopenia in adult-based research. These indices include mean platelet volume, platelet distribution width, and platelet-large cell ratio. Objective. To determine the values of platelet-derived indices in a pediatric population with diagnoses of thrombocytopenia and their etiologic correlation. Materials and methods. Analytic observational diagnostic-test study. The population for this analytical study was pediatric patients between 6 months and 18 years of age who had thrombocytopenia (<100x10(9/L. The study period was 18 months long. Results. Of 54 subjects, 18 (33.3% were diagnosed with idiopathic thrombocytopenic purpura, and 36 (66.7% were diagnosed with acute leukemia. Mean age was 7.4 years and 6.8 years for immune thrombocytopenic purpura and acute leukemia, respectively. Mean platelet distribution width values for immune thrombocytopenic purpura and acute leukemia were 15.08 fL and 10.73, respectively. Mean MPV for immune thrombocytopenic purpura and acute leukemia was 11.7 fL and 9.8 fL, respectively. Mean platelet-large cell ratio was 38.26% and 24.97% for idiopathic thrombocytopenic purpura and acute leukemia, respectively. Differences in these three distinct platelet indices between idiopathic thrombocytopenic purpura and acute leukemia were statistically significant (p=0.00. The area under the ROC curve for platelet-derived indices showed that they were adequate for defining the causes of thrombocytopenia. MPV and platelet-large cell ratio had an area under the curve of 0.89 and 0.88, respectively, while platelet size deviation width had an area under the curve of 0.903. Conclusions. Platelet-derived indices could be useful in the initial approach for the differential diagnosis of pediatric patients with thrombocytopenia.

  18. WIDTHS AND AVERAGE WIDTHS OF SOBOLEV CLASSES

    Institute of Scientific and Technical Information of China (English)

    刘永平; 许贵桥

    2003-01-01

    This paper concerns the problem of the Kolmogorov n-width, the linear n-width, the Gel'fand n-width and the Bernstein n-width of Sobolev classes of the periodicmultivariate functions in the space Lp(Td) and the average Bernstein σ-width, averageKolmogorov σ-widths, the average linear σ-widths of Sobolev classes of the multivariatequantities.

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

    Science.gov (United States)

    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 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 preeclampsia.

  20. The effect of lithology on valley width, terrace distribution, and coarse sediment provenance in a tectonically stable catchment with flat-lying stratigraphy

    Science.gov (United States)

    Amanda Keen-Zebert,; Hudson, Mark R.; Stephanie L. Shepherd,; Evan A. Thaler,

    2017-01-01

    How rock resistance or erodibility affects fluvial landforms and processes is an outstanding question in geomorphology that has recently garnered attention owing to the recognition that the erosion rates of bedrock channels largely set the pace of landscape evolution. In this work, we evaluate valley width, terrace distribution, and sediment provenance in terms of reach scale variation in lithology in the study reach and discuss the implications for landscape evolution in a catchment with relatively flat2

  1. A Young double-slit experiment using a single electron source: Oscillations in the angular distribution of Auger-line width

    Energy Technology Data Exchange (ETDEWEB)

    Fremont, F; Chesnel, J-Y [Universite de Caen-CEA-CNRS-EnsiCaen-CIMAP, 6 bd du Mal Juin, F-14050 Caen Cedex (France); Barrachina, R O; Suarez, S, E-mail: francois.fremont@ensicaen.f, E-mail: barra@cab.cnea.gov.a [Centro Atomico Bariloche and Instituto Balseiro 8400 S. C. de Bariloche, Rio Negro (Argentina)

    2009-11-01

    We present evidence for two-center interference effects in the autoionization of a Helium atom following a double capture process in a He''2''+ + H{sub 2} collision, by looking, not at the total intensity as in a previous article [1], but at the full width at half maximum of the energy distribution at a function of the observation angle.

  2. Comment on "Distribution of Partial Neutron Widths for Nuclei Close to a Maximum of the Neutron Strength Function"

    OpenAIRE

    Koehler, P. E.; Bečvář, F.; Krtička, M.; Harvey, J. A.; Guber, K. H.

    2011-01-01

    A recent Letter attempted to reconcile the disagreement between neutron resonance data and random matrix theory (RMT). To this end, a new formula was derived for transforming measured ({\\Gamma}_{{\\lambda}n}) to reduced ({\\Gamma}_{{\\lambda}n}^0) neutron widths for s-wave resonances ({\\lambda}=1,2,...) in nuclides near peaks of the s-wave neutron strength function. In this Comment, we show that such a rescaling would not, in general, be expected to reconcile the type of disagreement observed, a...

  3. Comment on "Distribution of Partial Neutron Widths for Nuclei Close to a Maximum of the Neutron Strength Function"

    CERN Document Server

    Koehler, P E; Krtička, M; Harvey, J A; Guber, K H

    2011-01-01

    A recent Letter attempted to reconcile the disagreement between neutron resonance data and random matrix theory (RMT). To this end, a new formula was derived for transforming measured ({\\Gamma}_{{\\lambda}n}) to reduced ({\\Gamma}_{{\\lambda}n}^0) neutron widths for s-wave resonances ({\\lambda}=1,2,...) in nuclides near peaks of the s-wave neutron strength function. In this Comment, we show that such a rescaling would not, in general, be expected to reconcile the type of disagreement observed, and demonstrate that indeed it does not for the specific cases in question. Hence, the disagreements between RMT and these data remain.

  4. Platelet function and activation in Cavalier King Charles Spaniels with subclinical chronic valvular heart disease.

    Science.gov (United States)

    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.

  5. Preoperative red cell distribution width and neutrophil-to-lymphocyte ratio predict survival in patients with epithelial ovarian cancer

    Science.gov (United States)

    Li, Zheng; Hong, Na; Robertson, Melissa; Wang, Chen; Jiang, Guoqian

    2017-01-01

    Several parameters of preoperative complete blood count (CBC) and inflammation-associated blood cell markers derived from them have been reported to correlate with prognosis in patients with epithelial ovarian cancer (EOC), but their prognostic importance and optimal cutoffs are still needed be elucidated. Clinic/pathological parameters, 5-year follow-up data and preoperative CBC parameters were obtained retrospectively in 654 EOC patients underwent primary surgery at Mayo Clinic. Cutoffs for neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), and monocyte-to-lymphocyte ratio (MLR) were optimized by receiver operating characteristic (ROC) curve. Prognostic significance for overall survival (OS) and recurrence free survival (RFS) were determined by Cox proportional hazards models and Kaplan-Meier method. Associations of RDW and NLR with clinic/pathological parameters were analyzed using non-parametric tests. RDW with cutoff 14.5 and NLR with cutoff 5.25 had independent prognostic significance for OS, while combined RDW and NLR scores stratified patients into low (RDW-low and NLR-low), intermediate (RDW-high or NLR-high) and high risk (RDW-high and NLR-high) groups, especially in patients with high-grade serous ovarian cancer (HGSOC). Moreover, high NLR was associated with poor RFS as well. Elevated RDW was strongly associated with age, whereas high NLR was strongly associated with stage, preoperative CA125 level and ascites at surgery. PMID:28223716

  6. Platelet count and platelet indices in women with preeclampsia

    Directory of Open Access Journals (Sweden)

    AlSheeha MA

    2016-11-01

    Full Text Available Muneera A AlSheeha,1 Rafi S Alaboudi,1 Mohammad A Alghasham,1 Javed Iqbal,2 Ishag Adam1 1Department of Obstetrics and Gynaecology, College of Medicine, Qassim University, Buriadah, 2Department of Obstetrics and Gynecology, Maternity and Children’s Hospital, Qassim, Kingdom of Saudi Arabia 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 preeclampsia (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. Keywords: preeclampsia, platelets, PDW, mean platelet

  7. On the determination of the He abundance distribution in globular clusters from the width of the main sequence

    Science.gov (United States)

    Cassisi, Santi; Salaris, Maurizio; Pietrinferni, Adriano; Hyder, David

    2017-01-01

    One crucial piece of information to study the origin of multiple stellar populations in globular clusters is the range of initial helium abundances ΔY amongst the sub-populations hosted by each cluster. These estimates are commonly obtained by measuring the width in colour of the unevolved main sequence in an optical colour-magnitude diagram (CMD). The measured colour spread is then compared with predictions from theoretical stellar isochrones with varying initial He abundances to determine ΔY. The availability of UV/optical magnitudes, thanks to the Hubble Space Telescope UV Legacy Survey of Galactic GCs project, will allow the homogeneous determination of ΔY for a large Galactic globular cluster sample. From a theoretical point of view, accurate UV CMDs can efficiently disentangle the various sub-populations, and main sequence colour differences in the ACS F606W - (F606W - F814W) diagram allow an estimate of ΔY. We demonstrate that from a theoretical perspective, the (F606W - F814W) colour is an extremely reliable He-abundance indicator. The derivative dY/d(F606W - F814W), computed at a fixed luminosity along the unevolved main sequence, is largely insensitive to the physical assumptions made in stellar model computations, being more sensitive to the choice of the bolometric correction scale, and is only slightly dependent on the adopted set of stellar models. From a theoretical point of view, the (F606W - F814W) colour width of the cluster main sequence is therefore a robust diagnostic of the ΔY range.

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

    Science.gov (United States)

    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 ( 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 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.

  9. On the determination of the He abundance distribution in globular clusters from the width of the main sequence

    CERN Document Server

    Cassisi, Santi; Pietrinferni, Adriano; Hyde, David

    2016-01-01

    One crucial piece of information to study the origin of multiple stellar populations in globular clusters, is the range of initial helium abundances $\\Delta{Y}$ amongst the sub-populations hosted by each cluster. These estimates are commonly obtained by measuring the width in colour of the unevolved main sequence in an optical colour-magnitude-diagram. The measured colour spread is then compared with predictions from theoretical stellar isochrones with varying initial He abundances, to determine $\\Delta{Y}$. The availability of UV/optical magnitudes thanks to the {\\sl HST UV Legacy Survey of Galactic GCs} project, will allow the homogeneous determination of $\\Delta{Y}$ for a large Galactic globular cluster sample. From a theoretical point of view, accurate UV CMDs can efficiently disentangle the various sub-populations, and main sequence colour differences in the ACS $F606W-(F606W-F814W)$ diagram allow an estimate of $\\Delta{Y}$. We demonstrate that from a theoretical perspective the ($F606W-F814W$) colour is...

  10. Distribution of secretory inhibitor of platelet microbicidal protein among urethral isolates with its correlation with prostatitis

    Institute of Scientific and Technical Information of China (English)

    Iuri B.Ivanov; Viktor A.Gritsenko; Michael D.Kuzmin

    2008-01-01

    Aim: To report the detection in vitro of secretory inhibitor of platelet microbicidal protein (SIPMP) phenotypes of urethral isolates along with a comparison with isolates from patients with or without chronic bacterial prostatitis (CBP). Methods: Urethral isolates of Staphylococcus spp. (n = 64), diphtheroids (n = 28), micrococci (n = 15),streptococci (n = 21), Enterobacteriaceae (n = 9) and Enterococcusfaecalis (n = 19) from patients with or without CBP were tested. SIPMP production was tested by inhibition of platelet microbicidal protein (PMP) bioactivity against Bacillus subtilis and was expressed as percentage of inhibition of PMP bactericidal activity. Results: A significantly higher proportion of CBP-strains (57.78% vs. 16.67%) reduced PMP-induced killing of Bacillus subtilis than non-CBP strains did (P < 0.01), SIPMP levels of staphylococci and Enterococcusfaecalis from the CBP group were significantly higher than those of the control group. Conclusion: These results suggest that SIPMP production is associated with the CBP source. Data from the present study might have significant implications for the understanding of the pathogenesis of CBP.

  11. 红细胞体积分布宽度与冠心病的关系研究%Correlation of red blood cell distribution width with coronary heart disease

    Institute of Scientific and Technical Information of China (English)

    盛春梅; 马礼坤

    2014-01-01

    Objective To assess the relation between red blood cell distribution width(RDW)and coronary heart disease (CHD).Methods A total of 152 patients with CHD by coronary angiography admitted to our hospital were assigned to coronary heart disease group, and another 67 healthy cases in hospital physical examination in the same period were selected as control group.The laboratory indicators,in-cluding RDW,red blood cell count(RBC),hemoglobin(HGB),average red blood cell volume(MCV),white blood cell count(WBC),hema-tocrit(Hct),platelet count(PLT),mean platelet volume(MPV),aspartate aminotransferase(AST),alanine aminotransferase(ALT),muscle, liver(Cr),blood urea nitrogen(BUN)of the two groups were compared.The severity of coronary artery lesions was evaluated by modified Gensini score method,and its correlation with RDW was analyzed.Results Compared with control group,RDW in CHD group increased sig-nificantly(P <0.05).Conclusion RDW is associated with CHD and the severity of coronary artery lesion,which could be a predictor for the severity of pathological changes in coronary artery.%目的:探讨红细胞分布宽度(RDW)与冠心病(CHD)的关系。方法选取冠状动脉造影确诊的152例 CHD 患者为 CHD 组,67例健康体检人群为对照组。对比分析两组人群的 RDW、红细胞计数(RBC)、血红蛋白(HGB)、红细胞平均体积(MCV)、血细胞比容(Hct)、白细胞计数(WBC)、血小板计数(PLT)、平均血小板体积(MPV)、天冬氨酸氨基转移酶(AST)、丙氨酸氨基转移酶(ALT)、血肌肝(Cr)、尿素氮(BUN);采用改良 Gensini 积分法评价冠状动脉病变的严重程度。结果与对照组比较, CHD 组 RDW 明显升高(P <0.05)。结论RDW 与 CHD 及冠状动脉病变严重程度存在一定关系,可以预测其严重程度。

  12. Changes in platelet functional parameters and CD62 P expression in liver cirrhosis.

    Science.gov (United States)

    Xianghong, G; Guanping, C; Fenghua, Y; Jiayin, W

    2013-12-01

    Hepatic impairment, portal hypertension, and multi-systemic damage could occur during liver cirrhosis's late stage. Bleeding is a complication of hepatic cirrhosis along with several changes including blood platelet count (BPC), mean platelet volume (MPV), platelet crit (PCT) and expression of platelet CD62P. Blood platelet count (BPC), mean platelet volume (MPV), platelet distribution width, and other indices are indirect reflections of CD62P parameters. To investigate the changes in platelet functional parameters and CD62 P expression in liver cirrhosis as a possible guide in clinical treatments and prognoses of liver cirrhosis. CD62P was tested by flow cytometry in liver cirrhosis. BPC, MPV, and PCT in peripheral blood were tested using an auto blood cell analyzer. Data were analyzed using SPSS11.0. The values of CD62P and MPV in patients was significantly higher than those of healthy donors (PPP, BPC, MPV, and platelet crit (PCT) show several changes in liver cirrhosis. It is useful to understand the relationship between hepatic cirrhosis severity and CD62P, BPC, MPV, PCT, timely monitoring of CD62P for treatment of hepatic cirrhosis in clinical treatment and prognosis.

  13. Mean corpuscular volume and red cell distribution width as predictors of left atrial stasis in patients with non-valvular atrial fibrillation.

    Science.gov (United States)

    Providência, Rui; Ferreira, Maria João; Gonçalves, Lino; Faustino, Ana; Paiva, Luís; Fernandes, Andreia; Barra, Sérgio; Pimenta, Joana; Leitão-Marques, António M

    2013-01-01

    The role of erythrocyte indexes for the prediction of left atrial stasis, assessed by transesophageal echocardiography in patients with non-valvular atrial fibrillation, has not been previously clarified. Single center cross-sectional study comprising 247 consecutive patients admitted to the emergency department due to symptomatic atrial fibrillation and undergoing transesophageal echocardiogram evaluation for exclusion of left atrial appendage thrombus (LAAT) before cardioversion. All patients had a complete blood count performed up to 12 hours prior to the transesophageal echocardiogram. Markers of left atrial stasis were sought: LAAT, dense spontaneous echocardiographic contrast (DSEC) and low flow velocities (LFV) in the left atrial appendage. Erythrocyte indexes' accuracy for detecting transesophageal echocardiogram changes was evaluated through receiver operating curve analysis. Binary logistic multivariate analysis, using solely erythrocyte indexes and in combination with other variables (i.e. CHADS2, CHA2DS2VASc classifications and left ventricle ejection fraction), was used for transesophageal echocardiogram endpoints prediction. LAAT was found in 8.5%, DSEC in 26.1% and LFV in 12.1%. Mean corpuscular volume and red cell distribution width were independent predictors of LAAT and DSEC. Despite adding incremental predictive value to each other, when clinical risk factors from CHADS2 and CHA2DS2VASc classifications and left ventricle ejection fraction were added to the models, only mean corpuscular volume remained an independent predictor of LAAT and DSEC. These findings suggest that mean corpuscular volume and red cell distribution width may be linked to left atrial stasis markers.

  14. SIGNIFICANCE OF PLATELET COUNT AND PLATELET INDICES IN PATIENTS WITH SOME THROMBOCYTOPENIC CONDITIONS

    Directory of Open Access Journals (Sweden)

    Omer Noureldaim Abdalla

    2016-01-01

    Full Text Available Background: Thrombocytopenia is one of the most frequent causes for hematologic consultation in the practice of medicine and can result from a wide variety of conditions. Objective: The study was conducted on behave of platelets count in tie with platelet volume indices to measure their consistency. Methods: The study was “prospective cross-sectional hospital based design” and conducted at Khartoum hospitals (A.Gasim, Jafar I A, and R.ICK. Studied populations texture has stipulated concurred diagnosis of heart disorders (HD, lymphoid neoplasms (LN, hypoplastic bone marrow (HPB, renal transplantation (RT, patients under chemotherapy (CT, and fully checked healthy Sudanese population (HSP. Platelet (PLT count and platelet volume index (PVI were measured using automated method of Sysmex KX-21N and the data was analyzed using SPSS. Results: does established (24 mean and standard for the study population among which (HSP was platelet distribution width (PDW (11.4±1.5 fl, mean platelet volume (MPV (9.3±0.8 fl, platelet large cell ratio (P- LCR (20.6±6.7% and PLT count (245±45 X109/L, and established correlations between PLT count and PVI in thrombocytopenic conditions. Conclusion: we conclude that, PVI has the ability to change from normal to higher or lower than (HSP in thrombocytopenic conditions and Sudanese has PVI mean lower than the mean of reference range, and there are inverse and reverse correlations between PLT count and PVI but not in (HSP and reverse correlation in between PVI except between PDW and P-LCR in (HPB

  15. Effects of red blood cell deformability on the non-uniform distribution of platelet-sized particles in blood flow through microchannels

    Science.gov (United States)

    Sugihara-Seki, Masako; Sakamoto, Keisuke; Itano, Tomoaki; Seki, Junji

    2016-11-01

    In blood flow through microvessels, platelets are known to have enhanced concentrations near the vessel wall, which is the so-called "near-wall excess (NWE)". This phenomenon is considered to be caused by the interaction with red blood cells (RBCs); since RBCs have a tendency to approach the vessel centerline due to their highly deformability, they may push away less deformable platelets toward the near-wall region. In order to examine this proposition by in vitro experiments, we measured the distribution of platelet-sized particles mixed in intact RBC or hardened RBC suspensions flowing through microchannels of 50 μm x 50 μm cross-section. Hardened RBCs were prepared by immersing human RBCs in glutaraldehayde solution of 40 - 4000 ppm. Fluorescent observations were conducted with the use of a confocal laser scanning microscope system with a high-speed video camera. It was found that platelet-sized particles exhibited high concentrations near the channel wall, i.e., NWE, when they were mixed in intact RBC suspensions. By contrast, the particles mixed in hardened RBC suspensions showed weak NWE or uniform distribution over the channel cross-section, indicating that deformability of RBCs plays an essential role in the NWE phenomenon.

  16. Platelet mimicry

    DEFF Research Database (Denmark)

    Moghimi, Seyed Moein; Hunter, Alan Christy; Peer, Dan

    2016-01-01

    Here we critically examine whether coating of nanoparticles with platelet membranes can truly disguise them against recognition by elements of the innate immune system. We further assess whether the "cloaking technology" can sufficiently equip nanoparticles with platelet-mimicking functionalities...

  17. Platelet Count

    Science.gov (United States)

    ... their spleen removed surgically Use of birth control pills (oral contraceptives) Some conditions may cause a temporary (transitory) increased ... increased platelet counts include estrogen and birth control pills (oral contraceptives). Mildly decreased platelet counts may be seen in ...

  18. A deterministic width function model

    Directory of Open Access Journals (Sweden)

    C. E. Puente

    2003-01-01

    Full Text Available Use of a deterministic fractal-multifractal (FM geometric method to model width functions of natural river networks, as derived distributions of simple multifractal measures via fractal interpolating functions, is reported. It is first demonstrated that the FM procedure may be used to simulate natural width functions, preserving their most relevant features like their overall shape and texture and their observed power-law scaling on their power spectra. It is then shown, via two natural river networks (Racoon and Brushy creeks in the United States, that the FM approach may also be used to closely approximate existing width functions.

  19. Predictive value of platelet-to-lymphocyte ratio in exacerbation of chronic obstructive pulmonary disease.

    Science.gov (United States)

    Karadeniz, Gülistan; Aktoğu, Serir; Erer, Onur Fevzi; Kır, Serpil Bulaç; Doruk, Sibel; Demir, Melike; Sonat, Kübra

    2016-07-01

    We aimed to assess the platelet-to-lymphocyte ratio (PLR) and platelet parameters in patients with chronic obstructive pulmonary disease (COPD). A total of 60 stable COPD patients, 50 acute exacerbation COPD patients and 50 healthy controls were enrolled in this study. The platelet distribution width and PLR were higher and the mean platelet volume was lower in the COPD patients during acute exacerbation compared with the stable patients and controls. The PLR was negatively correlated with the forced expiratory volume in 1 s. The PLR may be used as a useful and easily accessible tool for evaluating the ongoing inflammation during stable period and the disease severity during acute exacerbations in COPD patients.

  20. Megakaryocytes and platelets express nicotinic acetylcholine receptors but nicotine does not affect megakaryopoiesis or platelet function.

    Science.gov (United States)

    Schedel, Angelika; Kaiser, Kerstin; Uhlig, Stefanie; Lorenz, Florian; Sarin, Anip; Starigk, Julian; Hassmann, Dennis; Bieback, Karen; Bugert, Peter

    2016-01-01

    In our previous investigations we have shown that platelets and their precursors express nicotinic α7 acetylcholine receptors (nAChRα7) that are involved in platelet function and in vitro differentiation of the megakaryoblastic cell line MEG-01. In this study, we were interested in the expression analysis of additional nAChR and the effects of nicotine in an ex vivo model using megakaryocytic cells differentiated from cord blood derived CD34(+) cells (CBMK) and an in vivo model using blood samples from smokers. CBMK were differentiated with thrombopoietin (TPO) for up to 17 days. Quantitative real-time PCR (QRT-PCR), Western blot analysis and flow cytometry were used to investigate nAChR expression (nAChRα7, nAChRα4, nAChRβ2) and nicotine effects. In blood samples of 15 nonsmokers and 16 smokers platelet parameters (count, mean platelet volume--MPV and platelet distribution width--PDW) were determined as indicators for changes of in vivo megakaryopoiesis. Platelet function was determined by the use of whole blood aggregometry and flow cytometry. The functional role of nAChR was evaluated using specific antagonists in aggregometry. CHRNA7, CHRNA4 and CHRNB2 gene transcripts and the corresponding proteins could be identified in CBMK during all stages of differentiation. Platelets contain nAChRα7 and nAChRβ2 but not nAChRα4. Nicotine had no effect on TPO-induced differentiation of CBMK. There was no significant difference in all platelet parameters of the smokers compared to the nonsmokers. In line with this, cholinergic gene transcripts as well as the encoded proteins were equally expressed in both the study groups. Despite our observation of nAChR expression in megakaryopoiesis and platelets, we were not able to detect effects of nicotine in our ex vivo and in vivo models. Thus, the functional role of the nAChR in these cells remains open.

  1. The correlation of coronary heart disease with red blood cell distribution width and uric acid%红细胞分布宽度、尿酸与冠心病的相关性研究

    Institute of Scientific and Technical Information of China (English)

    张海云

    2016-01-01

    目的 探讨红细胞分布宽度(RDW)、尿酸(UA)水平与冠心病(CHD)的关系.方法 选取该院心内科住院的150例CHD患者(CHD组) ,同时选取健康对照者120例(对照组) ,对所有入选患者的RDW、红细胞(RBC)、血红蛋白(Hb)、红细胞平均体积(MCV)、白细胞(WBC)、血小板(PLT)、UA、血肌酐(Cr)、尿素氮(BUN)、血脂四项进行检测 ,并对数据进行分析.结果 与对照组RDW(12 .45 ± 0 .86)% 、UA(302 .21 ± 66 .46)μmol/L比较 ,CHD组RDW(13 .34 ± 0 .73)% 、UA(378 .32 ± 67 .20)μmol/L均显著升高 ,差异有统计学意义(P<0 .05).结论 RDW、UA对CHD的诊断具有重要意义.%Objective To investigate the correlation of coronary heart disease with the RDW(red blood cell distribution width) and UA(uric acid)level .Methods Chose 150 cases of coronary heart disease patients in our hospital(CHD group) ,at the same time selected 120 healthy cases as a normal control(control group) .Measured the RDW ,red blood cell (RBC) ,hemoglobin(Hb) ,mean corpuscular volume (MCV) ,white blood cell count(WBC) ,platelets(PLT) ,UA ,serum creatinine(Cr) ,blood urea nitrogen(BUN) , lipids four of the patients whose were selected ,then analyzed the data .Results The RDW(13 .34 ± 0 .73)% were significantly in-creased in CHD group compared with RDW (12 .45 ± 0 .86)% in the control group;The UA (378 .32 ± 67 .20)μmol/L were also significantly increased in CHD group compared with UA(302 .21 ± 66 .46)μmol/L in the control group(P<0 .05) .Conclusion RDW and UA has an important significance for the diagnosis of CHD .

  2. Red blood cell distribution width independently predicts medium-term mortality and major adverse cardiac events after an acute coronary syndrome

    Science.gov (United States)

    Turcato, Gianni; Serafini, Valentina; Dilda, Alice; Bovo, Chiara; Caruso, Beatrice; Ricci, Giorgio

    2016-01-01

    Background The value of red blood cell distribution width (RDW), a simple and inexpensive measure of anisocytosis, has been associated with the outcome of many human chronic disorders. Therefore, this retrospective study was aimed to investigate whether RDW may be associated with medium-term mortality and major adverse cardiac events (MACE) after an acute coronary syndrome (ACS). Methods A total number of 979 patients diagnosed with ACS were enrolled from June 2014 to November 2014, and followed-up until June 2015. Results The RDW value in patients with 3-month MACE and in those who died was significantly higher than that of patients without 3-month MACE (13.3% vs. 14.0%; P14.8% exhibited a significantly short survival than those with RDW ≤14.8% (331 vs. 465 days; P<0.001). Conclusions The results of this study confirm that RDW may be a valuable, easy and inexpensive parameter for stratifying the medium-term risk in patients with ACS. PMID:27500155

  3. Preoperative red cell distribution width: Not a useful prognostic indicator for 30-day mortality in patients who undergo major- or ultra-major noncardiac surgery

    Directory of Open Access Journals (Sweden)

    Yik-Nang Cheung

    2016-01-01

    Full Text Available Background: Red cell distribution width (RDW has been shown to be associated with mortality in cardiac surgical patients. This study investigates the association of RDW with the 30-day mortality for those patients who undergo major- or ultra-major noncardiac surgery. Methods: Patients who received major- or ultra-major noncardiac surgery between July 2012 and May 2013 were included in the study and patients those with preoperative hemoglobin 13.35% (P = 0.025, odds ratio [OR]: 1.52, INR (P = 0.008, OR: 4.49, albumin level (P < 0.001, OR: 1.10, use of antihypertensives (P = 0.001, OR: 1.82, and preoperative pulse rate (P = 0.006, OR: 1.02 independently predicted the 30-day mortality. However, the area under receiver operating characteristic curve for the prediction of 30-day mortality using RDW was only 0.614. Conclusions: Although preoperative RDW independently predicted 30-day mortality in patients who underwent major- or ultra-major noncardiac surgery, it may not serve as an influential prognostic indicator in view of its low sensitivity and specificity.

  4. The Acute Effect of the Antioxidant Drug U-74389G on Red Blood Cell Distribution Width Levels During Hypoxia Reoxygenation Injury in Rats

    Directory of Open Access Journals (Sweden)

    Tsompos Constantinos

    2015-12-01

    Full Text Available The AIM of this experimental study was to evaluate the effect of the antioxidant drug “U-74389G” in a rat model of hypoxia reoxygenation (HR using the previously established protocol. Effects of treatment were evaluated by mean red blood cell distribution width (RDW levels. MATERIALS AND METHODS: 40 rats of a mean weight of 231.875 g were employed in the study. RDW levels were determined at 60 min (groups A and C and at 120 min (groups B and D after starting the reoxygenation. Groups A and B received no drugs, whereas rats from groups C and D were administered with U-74389G. RESULTS: demonstrated that U-74389G administration significantly decreased the RDW levels by 4.96% + 2.27% (p = 0.0175. Reoxygenation time non-significantly decreased the RDW levels by 0.27% + 2.41% (p = 0.8889. Together, U-74389G administration and reoxygenation time non-significantly decreased the RDW levels by 2.54% + 1.39% (p = 0.0679. CONCLUSIONS: U-74389G administration particulary in concert without reperfusion declines the RDW levels even within the short - time context of 1.5 hours reperfusion.

  5. 红细胞分布宽度的临床应用新进展%Progress in Clinical Application of Red Blood Cell Distribution Width

    Institute of Scientific and Technical Information of China (English)

    何磊

    2013-01-01

    Red blood cell distribution width( RDW )is a coefficient of variation reflecting the change of the red blood cell volume,which was mostly often used in the diagnosis and differentiation of different types of anemia. In recent years the study found that RDW has a certain clinical value in the occurrence and prognosis judgment of the disease and predicting prognosis in acute and chronic heart failure, coronary atherosclerosis heart disease,hypertension,type 2 diabetes,etc..%红细胞分布宽度(RDW)是反映周围血红细胞体积大小变化的变异性系数,既往多用于对不同类型贫血的诊断以及鉴别诊断.近年来研究发现,RDW在急、慢性心功能不全、冠状动脉粥样硬化性心脏病、高血压病、2型糖尿病等疾病的发生发展、病变严重程度、并发症的发生以及判断预后等方面具有一定的临床价值.

  6. Platelet proteomics.

    Science.gov (United States)

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

    2012-01-01

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

  7. Prognostic value of red blood cell distribution width for patients with heart failure: a systematic review and meta-analysis of cohort studies.

    Directory of Open Access Journals (Sweden)

    Yuan-Lan Huang

    Full Text Available AIMS: Multiple studies have investigated the prognostic role of red blood cell distribution width (RDW for patients with heart failure (HF, but the results have been inconsistent. The aim of the present study was to estimate the impact of RDW on the prognosis of HF by performing a systematic review and meta-analysis. METHODS AND RESULTS: The Embase, PubMed, and Web of Science databases were searched up to November 16, 2013 to identify eligible cohort studies. The quality of each study was assessed using the Newcastle-Ottawa Scale (NOS. The association between RDW, either on admission or at discharge, and HF outcomes (all-cause mortality [ACM], heart transplantation, cardiovascular mortality, and rehospitalization, etc. were reviewed. The overall hazard ratio (HR for the effect of RDW on ACM was pooled using a random-effects model, and the publication bias was evaluated using funnel plots and Eggers' tests. Seventeen studies, with a total of 18288 HF patients, were included for systematic review. All eligible studies indicated that RDW on admission and RDW at discharge, as well as its change during treatment, were of prognostic significance for HF patients. The HR for the effect of a 1% increase in baseline RDW on ACM was 1.10 (95% confidence interval: 1.07-1.13, based on pooling of nine studies that provided related data. However, publication bias was observed among these studies. CONCLUSIONS: HF patients with higher RDW may have poorer prognosis than those with lower RDW. Further studies are needed to explore the potential mechanisms underlying this association.

  8. The red cell distribution width as a sensitive biomarker for assessing the pulmonary function in automobile welders- a cross sectional study.

    Science.gov (United States)

    Subhashree, A R; Shanthi, B; Parameaswari, P J

    2013-01-01

    Welding fumes are considered as a risk factor for pulmonary diseases and a periodic spirometry is essential to evaluate the lung function of the welders. The Red Cell Distribution Width (RDW) is a red cell measurement which is provided by automated haematology analyzers. It reflects the range of the red cell sizes which are measured within a sample. Few studies have shown a relationship between the RDW values and the changes in the spirometry. This study was aimed at correlating the RDW% and the spirometry FEV1/FVC ratio (%) among automobile welders (cases). Further, we have analyzed the effect of smoking on the FEV1/FVC ratio% and the RDW% in the cases. A cross sectional study was done on 50 welders and 50 non-welding office workers (controls) who were working in an automobile industry on the outskirts of Chennai, india. All the cases were arc welders and the controls were from the same production unit, who had never worked as welders. This study was conducted during the period from March 2012 to May 2012. The demographic data, smoking habits, work history and the respiratory symptoms were gathered by using a standard self -administered questionnaire. A complete haemogram study was done and pulmonary function tests were performed for both the cases and the controls. All the cases and the controls were examined in the hospital outpatients room and subsequently, their blood samples were collected. The pulmonary function tests were conducted in the spirometry room in the hospital. The statistical analysis was done using the SPSS, version 15.0. A statistically significant inverse correlation was found between the RDW% and the FEV1/FVC ratio% in the cases. RDW can be used as a biomarker to identify the pulmonary compromise in automobile welders.

  9. Associations between accelerometer-assessed sedentary behavior, physical activity and objectively-measured cardiorespiratory fitness with red blood cell distribution width.

    Science.gov (United States)

    Edwards, Meghan K; Loprinzi, Paul D

    2016-10-15

    Emerging work identifies red blood cell distribution width (RDW) as a unique biomarker independently associated with cardiovascular disease and mortality. Encouragingly, recent research demonstrates individual associations of sedentary behavior, physical activity and cardiorespiratory fitness with RDW. However, no study has evaluated their independent and combined associations on RDW, which was this study's purpose. Data from the 2003-2004 National Health and Nutrition Examination Survey were used (N=627 adults 20-49yrs). Sedentary behavior and MVPA were objectively assessed (accelerometry) with cardiorespiratory fitness determined from a submaximal treadmill-based test. Participants were classified as above or below the median values for each of these three parameters, with a PACS (Physical Activity Cardiorespiratory Sedentary) score ranging from 0 to 3, indicating the participant number of these three positive characteristics. A blood sample was obtained from each participant to assess RDW. Only above median MVPA (OR=0.47; 95% CI: 0.32-0.68) was independently associated with a reduced odds of having an elevated RDW. With regard to the additive model, and after adjustment, the odds ratio (95% CI) for the PACS score of 1 (vs. 0), 2 (vs. 0), and 3 (vs. 0), respectively, were 0.81 (0.45-1.45; P=0.46), 0.66 (0.44-0.99; P=0.04) and 0.35 (0.18-0.68; P=0.004). When considering sedentary behavior, MVPA, and cardiorespiratory fitness, only MVPA was associated with reduced odds of elevated RDW, but those with all three characteristics had the lowest odds of elevated RDW. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  10. The Value of Erythrocyte Indices and Red Cell Volume Distribution Width in Differential Diagnosis of Iron Deficiency Anemia and Anemia of Chronic Disease

    Directory of Open Access Journals (Sweden)

    Abdullah Altıntaş

    2007-01-01

    Full Text Available Iron deficiency anemia (IDA and anemia of chronic disease are the most commonly confused anemias. We investigate the diagnostic value of erythrocyte indices, red cell volume distribution width, and serum ferritin levels to make differential diagnosis of anemia in controls and anemic patients.Iron deficiency anemia (44 patients, anemia of chronic disease (41, IDA with anemia of chronic disease (17 and control (50 groups were compared. We performed serum ferritin, CBC, and sedimentation rate in all patientsand bone marrow aspiration in patients with anemia of chronic disease.Although mean cell volume (MCV and mean corpuscular hemoglobin (MCH are low in IDA and anemia of chronic disease, it is much striking in the former one (p<0.001, p<0.001. Only 7.3% of patients with anemia of chronic disease had a MCV<70 fL and MCH<24 pg, 90.0% of patients with IDA were below that cut-off point. Serum ferritin means were in patients with IDA and anemia of chronic disease were 4.6±3.3 and 489.6 ±519.9 ng/ml, respectively.The probability of IDA is low when RDW is normal in microcytic anemias. RDW is high in half of patients with anemia of chronic disease. Reference values for ferritin must be changed in patients with anemia of chronic disease and IDA. If serum ferritin is 57.6-146.4 ng/ml anemia of chronic disease and iron deficiency must ruled out by other diagnostic tests.

  11. CD(4) has bounded width

    CERN Document Server

    Carvalho, Catarina; Marković, Petar; Maróti, Miklós

    2007-01-01

    We prove that the constraint languages invariant under a short sequence of J\\'onsson terms (containing at most three non-trivial ternary terms) are tractable by showing that they have bounded width. This improves the previous result by Kiss and Valeriote and presents some evidence that the Larose-Zadori conjecture holds in the congruence-distributive case.

  12. Non-cardiac factors for prediction of response to cardiac resynchronization therapy: The value of baseline, and of serial changes, in red cell distribution width.

    Science.gov (United States)

    Carluccio, Erberto; Biagioli, Paolo; Alunni, Gianfranco; Murrone, Adriano; Zingarini, Gianluca; Coiro, Stefano; D'Antonio, Antonella; Mengoni, Anna; Cerasa, Maria Francesca; Ambrosio, Giuseppe

    2017-09-15

    Increased red blood cell distribution width (RDW) has been associated with poor outcome after cardiac resynchronization therapy (CRT). However, whether baseline RDW, and its serial changes after CRT implant, have incremental prognostic value is unknown. In 148 consecutive patients (age, 68±9years; 122 men) undergoing CRT, RDW was assessed before and 3months after implant. Patients were categorized according to baseline RDW (≤14.5% vs >14.5%); and as "stable", "decreased", "increased", relative to post-implant changes. Primary end-point was a composite of death/HF hospitalization during follow-up (median 21months). A reduction in left ventricular (LV) end-systolic volume by ≥15% at 6-month identified LV reverse remodeling. By multivariable logistic regression analysis "increased" (OR:0.22, 95%CI: 0.07-0.69, P=0.010) and "stable-high" RDW at follow-up (OR: 0.39, 95%CI: 0.17-0.89, P=0.027) showed a lower likelihood to develop LV reverse remodeling, while baseline RDW was no longer predictive of LV remodeling. During follow-up, there were 57 events. Baseline RDW>14.5% (HR: 2.24, 95%CI: 1.05-4.77, P=0.036), "increased" (HR: 2.55, 95% CI: 1.09-5.97, P=0.030) and "stable-high" RDW (HR: 2.95, 95% CI: 1.45-5.99, P=0.003) independently predicted outcome after adjusting for functional improvement after CRT, radial dyssynchrony, BNP, creatinine clearance, and left atrial volume index. However, integrated discrimination improvement and net reclassification improvement were not statistically significant when both baseline RDW and its changes were added to a base predictive model. Increased and stable-high values of RDW were independently associated with both LV reverse remodeling and outcome after CRT; however, RDW did not show any incremental predictive value. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. Relation between Red Cell Distribution Width and Fibroblast Growth Factor 23 Cleaving in Patients with Chronic Kidney Disease and Heart Failure.

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    Fenna van Breda

    Full Text Available In chronic kidney disease (CKD, both anemia and deregulated phosphate metabolism are common and predictive of adverse outcome. Previous studies suggest that iron status influences phosphate metabolism by modulating proteolytic cleavage of FGF23 into C-terminal fragments. Red cell distribution width (RDW was recently identified as a strong prognostic determinant for cardiovascular morbidity and mortality, independently of iron status. We assessed whether RDW is associated with FGF23 cleaving in CKD patients with heart failure.The associations between RDW and either intact FGF23 (iFGF23, C-terminal FGF23 (cFGF23, reflecting iFGF23 and C-terminal fragments together and the iFGF23/cFGF23 ratio were analyzed in 52 patients with CKD (eGFR 34,9 ± 13.9 ml/min/1.73m2 and chronic heart failure (CHF. Associations between RDW and FGF23 forms were studied by linear regression analysis adjusted for parameters of renal function, iron metabolism, phosphate metabolism and inflammation.Median cFGF23 levels were 197.5 [110-408.5] RU/ml, median iFGF23 levels were 107.3 [65.1-162.2] pg/ml and median FGF23 ratio was 0.80 [0.37-0.86]. Mean RDW was 14.1 ± 1.2%. cFGF23 and RDW were associated (β = 1.63 x 10(-3, P < 0.001, whereas iFGF23 and RDW were not (β = -1.38 x 10(-3, P = 0.336. The iFGF23/cFGF23 ratio was inversely associated with RDW. The difference between cFGF23 and iFGF23 (cFGF23- iFGF23 was positively associated with RDW (β = 1.74 x 10(-3, P < 0.001. The association between cFGF23 and RDW persisted upon multivariable linear regression analysis, adjusted for parameters of renal function, phosphate metabolism, iron metabolism and inflammation (β = 0.97 x 10(-3, P = 0.047.RDW is associated with cFGF23 but not with iFGF23 levels in patients with CKD and CHF. This suggests a connection between RDW and FGF23 catabolism, independent of iron status and inflammation. Future studies are needed to unravel underlying mechanisms and whether these pertain to the link

  14. [STRUCTURAL CHARACTERIZATION OF PLATELETS AND PLATELET-DERIVED MICROVESICLES].

    Science.gov (United States)

    Ponomareva, A A; Nevzorova, T A; Mordakhanova, E R; Andrianova, I A; Litvinov, R I

    2016-01-01

    Platelets are the anucleated blood cells, wich together with the fibrin stop bleeding (hemostasis). Cellular microvesicles are membrane-surrounded microparticles released into extracellular space upon activation and/or apoptosis of various cells. Platelet-derived macrovesicles from the major population of circulating blood microparticles that play an important role in hemostasis and thrombosis. Despite numerous studies on the pathophysiology of platelet-derived macrovesicles, mechanisms of their formation and structural details remain poorly understood. Here we investigated the ultrastructure of parental platelets and platelet-derived microvesicles formed in vitro by quiescent cells as well as by cells stimulated with one of the following activators: arachidonic acid, ADP, thrombin, calcium ionophore A23187. Using transmission electron microscopy of human platelets and isolated microvesicles, we analyzed the intracellular origin, steps of formation, structural diversity, and size distributions of the subcellular particles. We have revealed that thrombin, unlike other stimuli, not only induced vesiculation of the plasma membrane but also caused break-up of the cells followed by formation of microparticles that are comparable with microvesicles by size. A fraction of these microparticles contained cellular organelles surrounded by a thin membrane. The size of platelet-derived macrovesicles varied from 30 nm to 500 nm, however, the size distributions depended on the nature of a cell-activating stimulus. The results obtained provide new information about the formation of platelet-derived macrovesicles and their structural diversity, wich is important to understand their multiple functions in normal and disease states.

  15. Acquired platelet function defect

    Science.gov (United States)

    Acquired qualitative platelet disorders; Acquired disorders of platelet function ... blood clotting. Disorders that can cause problems in platelet function include: Idiopathic thrombocytopenic purpura Chronic myelogenous leukemia Multiple ...

  16. Platelet Donation

    Science.gov (United States)

    ... of gratitude that washed over me when I saw those platelets going into my husband’s body. I ... Needles LGBTQ+ Donors Blood Donor Community SleevesUp Games Facebook Avatars and Badges Banners eCards Red Cross Information ...

  17. Experimental study on rehydration conditions of freeze-dried platelets

    Institute of Scientific and Technical Information of China (English)

    Ju-li FAN; Xian-guo XU; Shao-zhi ZHANG; Fa-ming ZHU; Guang-ming CHEN; Li-xing YAN

    2009-01-01

    A rehydration process for freeze-dried human platelets was studied on 1 ml of samples.The effects of prehydration duration,prehydration temperature,an rehydration solution on the recovery rate,mean platelet volume(MPV),and platelet distribution width(PDW)were investigated.The mass changes during the prehydration process were also studied.Three prehydration durations:0,1.5,and 3.5 h,and two rehydration solutions:platelet-poor plasma and phosphate-buffered saline(PBS),were tested.It was found that:(1)the prehydration was of significance;(2)1.5 h of prehydration had better effects than 3.5 h of prehydration;(3)as a rehydration solution,the platelet-poor plasma behaved better than the PBS.The impacts of prehydration duration and temperature on the results were studied.There was almost no difference between 35 and 37℃.Among all the prehydration durations tested,15,30,60,90,and 120 min,the best result was achieved with the time duration of 15 min.The weights of prehydrated platelets at the end of each test were measured and the water contents were calculated.Atier 15 min of prehydration,the water contents in the samples were about(4.8±0.01)%and(5.27±0.29)%(w/w)corresponding to the conditions of 35 and 37 ℃.respectively.These results will be helpful for further studies on the freeze-drying of mammalian cells.

  18. Platelet indices and platelet-to-lymphocyte ratio predict coronary chronic total occlusion in patients with acute ST-elevation myocardial infarction

    Directory of Open Access Journals (Sweden)

    Hadadi Laszlo

    2015-12-01

    Full Text Available Coronary chronic total occlusion (CTO is caused by organized thrombi or atherosclerotic plaque progression. The presence of a CTO is an independent predictor of mortality in patients presenting with ST-segment elevation myocardial infarction (STEMI. Platelets have a crucial role in the pathophysiology of atherosclerosis. The aim of this retrospective study was to investigate platelet indices as predictors of CTO in patients with STEMI treated with primary percutaneous coronary intervention (pPCI. A total number of 334 patients admitted for STEMI between January 2011 and December 2013 were included and divided in two groups based on the presence of CTO (48 patients in CTO+ group, 286 patients in CTO-group. Platelet count, mean platelet volume (MPV, platelet distribution width (PDW, platelet-large cell ratio (P-LCR, lymphocyte and neutrophil count determined on admission were analyzed. MPV was larger in patients with CTO compared with patients without CTO (p=0.02, as were PDW (p=0.03 and P-LCR (p=0.01. Platelet-to-lymphocyte ratio (PLT/LYM was lower in patients with CTO: 105.2 (75.86-159.1 compared to 137 (97-188.1, p<0.01. Receiver-operator characteristic curve analysis identified an area under the curve of 0.61 (95%CI=0.57-0.67, p< 0.01 for PLT/LYM in predicting the presence of a CTO, with a cut-off value at 97.73. Lower values than this were independent predictors of a CTO in multivariate logistic regression analysis, with an Odds Ratio of 2.2 (95%CI=1.15-4.20, p=0.02. Our results support the use of platelet indices and PLT/LYM as predictors of CTO in patients presenting with STEMI.

  19. Association between high platelet indices and proteinuria in patients with hypertension.

    Science.gov (United States)

    Ates, Ihsan; Bulut, Mesudiye; Ozkayar, Nihal; Dede, Fatih

    2015-11-01

    We aimed to determine the association between platelet indices including plateletcrit (PCT), mean platelet volume (MPV), platelet distribution width (PDW), and proteinuria associated with hypertension (HT) as well as the relative power of each to predict proteinuria. The study included 223 patients (68 men and 155 women) with primary HT. PCT, MPV, PDW, and proteinuria levels were measured. The patients were divided into two groups according to proteinuria status based on 24-hr urinary protein excretion: proteinuria (+) group (15 men and 40 women) and proteinuria (-) group (53 men and 115 women). The mean and SD of platelet count, PDW, PCT, and MPV were 278.8±49.6×10⁸/L, 13.5±1.8%, 0.31±0.07%, and 11.3±2.6 fL, respectively. The mean platelet count, PCT, MPV, and PDW were significantly higher in the proteinuria (+) group than in the proteinuria (-) group (Pproteinuria according to a stepwise regression analysis of PDW, PCT, and MPV. PCT was the strongest independent predictor of proteinuria. The platelet indices PCT, PDW, and MPV were significantly higher in patients with proteinuria than in those without it. Among these three indices, PCT was the strongest predictor of proteinuria.

  20. Platelet volume indices as predictive biomarkers for diabetic complications in Type 2 diabetic patients

    Science.gov (United States)

    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 diabetics with and without complications and nondiabetics (P 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

  1. Analyzing the average intensity distribution and beam width evolution of phase-locked partially coherent radial flat-topped array laser beams in oceanic turbulence

    Science.gov (United States)

    Yousefi, M.; Kashani, F. D.; Mashal, A.

    2017-02-01

    In this research, an analytical expression for cross-spectral density matrix elements (and consequently, average intensity) of partially coherent flat-topped (PCFT) radial array laser beams in weak oceanic turbulence are derived based on the extended Huygens-Fresnel principle and the previously developed knowledge of the propagation of a partially coherent beam in atmosphere. Mean-squared beam width is calculated analytically using average intensity formula. The simulation is done by considering the effects of source parameters (such as the radius of the array setup’s circle and effective width of spectral degree of coherence) and turbulent ocean factors (such as the rate of dissipation of the turbulent kinetic energy per unit mass of fluid and relative strength of temperature-salinity fluctuations, Kolmogorov micro-scale, and the rate of dissipation of the mean squared temperature) in detail. It is found that when salinity fluctuations in the ocean dominate temperature fluctuations, the average intensity of the PCFT array beam becomes more broad and the array beam profile conversion process to a single wider Gaussian beam profile will occur at a faster rate. For the same turbulent conditions and the same initial beam width, the divergence of a flat-topped array beam is less than the Gaussian array beam. The simulation and calculation results are shown by graphs.

  2. 红细胞体积分布宽度与心血管疾病的研究进展%Progress in red blood cell distribution width and cardiovascular diseases

    Institute of Scientific and Technical Information of China (English)

    陈渠通; 朱辰; 吴晓虹

    2015-01-01

    Red blood cell distribution width (RDW) is a classic index for hematological disease differential diagnosis. Recently, accumulated studies have found that RDW was closely associated with the incidence, diagnosis and prognosis of various cardiovascular diseases. In present review, the relationships between RDW and heart failure, acute myocardial infarction etc. were summarized.%红细胞体积分布宽度(red blood cell distribution width,RDW)是血液系统疾病鉴别诊断的经典指标.近年来越来越多的研究发现RDW与心血管疾病的发生、诊断和预后密切相关.本文对近年来有关RDW与心力衰竭、急性心肌梗死等心血管疾病的研究进行简综述.

  3. Distribution of secretory inhibitor of platelet microbiddal protein among anaerobic bacteria isolated from stool of children with diarrhea

    Institute of Scientific and Technical Information of China (English)

    Iuri B Ivanov; Viktor A Gritsenko

    2008-01-01

    AIM: To study the secretory inhibitor of platelet microbicidal protein (SIPHP) phenotypes of faecal anaerobic isolates from patients with diarrhea.METHODS: Faecal isolates of anaerobic bacteria(B.fragiliS,n=42; B.longum,n=70;A.israelii,n=21;E.lentum,n=12) from children with diarrhea were tested.SlPHP production was tested by inhibition of platelet microbicidal protein (PHP) bioactivity against B.subtilis and was expressed as percentage of inhibition of PMP bactericidal activity.RESULTS: Among anaerobic isolates 80% of B.Iongum strains,85.7% of A.israelii strains,50%of E.lentum strains and 92.86% of B.fragilis strains were SIPMP-positive.The isolated anaerobic organisms demonstrated SIPHP production at a mean level of 13.8%±0.7%,14.7%±1.8%,3.9%±0.9% (P<0.05) and 26.8%±7.5% (P<0.05) for bifidobacteria,A.israelii,E.lentum and B.fragilis,respectively.CONCLUSION: Data from the present study may have significant implications in understanding the pathogenesis of microecological disorders in the intestine,as well as for future improvement in the prevention and therapy of anaerobe-associated infections.

  4. Red Blood Cell Distribution Width (RDW in thorougbred horses from 12 to 24 months of age/ Valores da amplitude de distribuição do tamanho dos eritrócitos (RDW – Red Cell Distribution Width em equinos da raça puro sangue inglês (PSI de ambos os sexos de 12 a 24 meses de idade

    Directory of Open Access Journals (Sweden)

    Raimundo Souza Lopes

    2001-05-01

    Full Text Available The purpose of this study was to establish reference values for red blood cell distribution width (RDW in health horses. We obtained blood samples through jugular punctured from 90 clinicaly health thorougbred horses between 12 and 24 months of age. Blood was obtained in a Cell-Dyn 3500 (Abbott Diagnostic cell counter. Mean ± standart deviation values for RDW in male horses were 26,90 ± 1,41, whereas in females values were 26,89 ± 1,75. There were no differences in the RDW values between sexes, therefore, our reference values can be used in both males and females.O objetivo do presente estudo foi estabelecer valores da amplitude de distribuição do tamanho dos eritrócitos (RDW em eqüinos clinicamente sadios. Foram utilizadas 90 amostras de sangue de eqüinos da raça Puro Sangue Inglês (PSI, clinicamente sadios de 12 a 24 meses de idade, obtidas por venipunção jugular em tubos à vácuo contendo EDTA 10%. Posteriormente as amostras foram processadas no contador automático de células Cell-Dyn 3500 (Abbott Diagnostic. Os valores médios e o desvios-padrão para o RDW (% de machos foi de 26,90 ± 1,41 e para as fêmeas de 26,89 ± 1,75. Os resultados demonstram não haver diferenças nos valores de RDW para machos e fêmeas, podendo ser utilizados como referência para ambos os sexos.

  5. Fractal and Euclidean descriptors of platelet shape.

    Science.gov (United States)

    Kraus, Max-Joseph; Neeb, Heiko; Strasser, Erwin F

    2014-01-01

    Platelet shape change is a dynamic membrane surface process that exhibits remarkable morphological heterogeneity. Once the outline of an irregular shape is identified and segmented from a digital image, several mathematical descriptors can be applied to numerical characterize the irregularity of the shapes surface. 13072 platelet outlines (PLO) were segmented automatically from 1928 microscopic images using a newly developed algorithm for the software product Matlab R2012b. The fractal dimension (FD), circularity, eccentricity, area and perimeter of each PLO were determined. 972 PLO were randomly assigned for computer-assisted manual measurement of platelet diameter as well as number, width and length of filopodia per platelet. FD can be used as a surrogate parameter for determining the roughness of the PLO and circularity can be used as a surrogate to estimate the number and length of filopodia. The relationship between FD and perimeter of the PLO reveals the existence of distinct groups of platelets with significant structural differences which may be caused by platelet activation. This new method allows for the standardized continuous numerical classification of platelet shape and its dynamic change, which is useful for the analysis of altered platelet activity (e.g. inflammatory diseases, contact activation, drug testing).

  6. 血红蛋白及红细胞分布宽度预测动静脉内瘘晚期血栓形成的研究%Hemoglobin and red cell distribution width for the prediction of late thrombosis of arteriovenous fistula

    Institute of Scientific and Technical Information of China (English)

    段书众; 董巧荣; 王景福; 张宝红

    2015-01-01

    Objective To probe relatively cheap and generally available laboratory test for predicting late thrombosis of arteriovenous fistu-la( AVF). Methods Retrospective analysis of laboratory data of hemoglobin( HGB),red cell distribution width-standard deviation( RDW-SD),red cell distribution width-coefficient of variation( RDW-CV),platelet,triglyceride and cholesterol was undertaken in 30 patients with late thrombosis of arteriovenous fistula. Thirty patients with AVF for maintenance hemodialysis but without thrombosis in the same hemodialysis center were as control. The above parameters were compared between two groups. Results The values of HGB and RDW in patients with throm-bosis were higher than those in control group,and the differences were statistically significant(all P 0. 05). Conclusion HGB and RDW may be used as the indicator for the prediction of late thrombosis of AVF.%目的:寻找廉价的、易于获得的能预测透析用动静脉内瘘晚期血栓形成的化验指标。方法回顾性研究30例动静脉内瘘晚期血栓形成患者的血红蛋白、红细胞分布宽度、血小板计数、甘油三酯、胆固醇;选择同一透析中心内瘘流量良好患者30例作为对照组,收集上述数据。比较两组间指标差异。结果晚期血栓形成者血红蛋白、红细胞分布宽度均明显高于对照组( P 0.05)。结论血红蛋白、红细胞分布宽度可作为预测动静脉内瘘晚期血栓形成的实验室指标。

  7. Platelet Function Tests

    Science.gov (United States)

    ... be limited. Home Visit Global Sites Search Help? Platelet Function Tests Share this page: Was this page helpful? ... their patients by ordering one or more platelet function tests. Platelet function testing may include one or more of ...

  8. Congenital platelet function defects

    Science.gov (United States)

    ... storage pool disorder; Glanzmann's thrombasthenia; Bernard-Soulier syndrome; Platelet function defects - congenital ... Congenital platelet function defects are bleeding disorders that ... function, even though there are normal platelet numbers. Most ...

  9. Single-step separation of platelets from whole blood coupled with digital quantification by interfacial platelet cytometry (iPC).

    Science.gov (United States)

    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 (

  10. Correlation of red cell distribution width with the severity of coronary artery disease: a large Chinese cohort study from a single center

    Institute of Scientific and Technical Information of China (English)

    MA Feng-lian; LI Sha; LI Xiao-lin; LIU Jun; QING Ping; GUO Yuan-lin; XU Rui-xia

    2013-01-01

    Background It has been reported that increased red blood cell width (RDW) is a marker associated with the presence and adverse outcomes of various cardiovascular diseases.The aim of the present study was prospectively evaluate the severity of coronary artery disease (CAD) and RDW in a large Chinese cohort.Methods A total of 677 consecutive individuals who underwent coronary angiography due to the presence of angina-like chest pain and/or positive treadmill exercise test were enrolled in this study.All patients received coronary angiography and were then divided into two groups based on the results of coronary angiography (CAD group (n=499) and control group (n=178)).The clinical information including classical CAD risk factors and RDW were analyzed to identify their relationship to CAD.The severity of CAD was evaluated by Gensini score and its relationship with RDW was also analyzed.Results Patients with angiographic CAD had significantly elevated RDW levels compared with controls ((12.95±0.77)%vs.(12.73±0.83)%,P=0.001).There was a significant positive correlation between RDW and the Gensini score (r=0.37,P <0.001).In multivariate Logistic regression analysis,RDW was demonstrated to be an independent predictor for both angiographic CAD (OR=1.34,95% CI.1.02-1.77,P <0.05) and for a higher Gensini score (>13,OR=2.23,95% CI.1.62-3.08,P <0.001).In a receiver operating characteristic (ROC) curve analysis,an RDW value of 12.85% was identified as an effective cut-point in predicting the presence or absence of CAD with a sensitivity of 50.0% and a specificity of 65.2%.Conclusion RDW is associated with both presence of CAD and the severity of coronary stenosis,suggesting that it might be a readily available marker for the prediction of CAD and its severity.

  11. 红细胞分布宽度在急性冠状动脉综合征中的研究进展%Research Progress of Red Blood Cell Distribution Width on Acute Coronary Syndrome

    Institute of Scientific and Technical Information of China (English)

    潘崇(综述); 李佳(审校)

    2016-01-01

    As a parameter routinely measured by most modern hematology analyzers ,red blood cell distribution width ( RDW) reflects variability in the size of circulating red blood cells .Increasing RDW is an indicator for the adverse prognosis of acute coronary syndrome and can be an independent predictor for the prognosis of cardiovascular disease .The aim of this review is to describe the prognostic utility of RDW in patients with acute coronary syndromes and to elucidate the mechanism and clinical application underlying the relationship between elevat -ed RDW values and poor patient prognosis .%红细胞分布宽度( red blood cell distribution width ,RDW)作为血常规中的一项参数,反映红细胞大小异质性。近年来的研究证实,RDW值与心血管疾病间具有重要相关性,RDW值升高预示急性冠状动脉综合征患者不良预后,RDW是急性冠状动脉综合征患者预后的独立预测因子。现就RDW值在急性冠状动脉综合征患者预后、作用机制及其临床应用价值的研究进展做一综述。

  12. 红细胞分布宽度在肺部疾病中的临床价值%The clinical value of red cell distribution width in pulmonary diseases

    Institute of Scientific and Technical Information of China (English)

    杨妮; 柯蕊; 刘原

    2015-01-01

    红细胞分布宽度(red cell distribution width,RDW)可反映外周血红细胞大小不一的程度,是评价红细胞异质性的参数,临床上常用于贫血的诊断和鉴别诊断。近年来,RDW 在评估肺部疾病严重程度和预后中的作用逐步得到了人们的重视。研究证实,RDW 的变化可能是整体上反映与患者病情和预后密切相关的因素,从而在提示肺部疾病的病变程度和远期预后中发挥重要作用。%Red cell distribution width (RDW)is a measurement of the size variation as well as an index of the heterogeneity of the erythrocytes.It is used clinically to differentiate different types of anemia.Recently,a strong association of RDW levels with clinical parameters and prognosis of lung disease has drawn people′s attention.It had been demonstrated that RDW values may reflect many factors which associated with the patient′s condition and prognosis,thus play an important role in predicting the severity and long-term prognosis of lung diseases.

  13. [Calculation of the dose distribution of high-energy electrons within and behind tissue inhomogeneities of any width. II. Influence of multiple scattering (author's transl)].

    Science.gov (United States)

    Mandour, M A; Harder, D

    1978-08-01

    The algorithn proposed in 1976 to allow for the influences of tissue inhomogeneities in electron beam dose distributions has been improved. A factor adopted from Sternheimer corrects for differences in lateral displacement by multiple scattering within the inhomogeneity resp. the equivalent layer of the homogeneous medium. The algorithm has been tested by direct comparison with Monte Carlo computations for the example of cylindrical cavities in carbon at Eo=10 MeV and resulted in a very close approximation.

  14. Platelet Count and Mean Platelet Volume in Patients with Nasal Polyposis

    Directory of Open Access Journals (Sweden)

    Asli Tanrivermis Sayit

    2014-12-01

    Full Text Available Aim: Nasal polyps (NPs are the most common reason for nasal obstruction, with a prevalence of 1-4%. Although the etiology is not clearly known, chronic infections and mechanical, immunological, and biochemical factors can play a role in the etiology. Recently, mean platelet volume (MPV was recognized as a simple inflammatory marker in the inflammatory disease. In this study, we aimed to evaluate platelet (PLT and MPV in patients with NPs. Material and Method: This study included 80 histopathologically proven patients with NPs and 80 age- and sex-matched healthy subjects as controls. The Lund-Mackay staging system was used to evalute paranasal sinus CT scans, in patients with NPs, and paranasal sinus CT scores were recorded. Values of MPV, platelet (PLT, platelet crit (PCT and platelet distribution width (PDW were assessed in NP and control groups. Results: MPV and PLT values were found to be low in patients with NPs, at 8.57±1.62 fL and 259.99±62.03 x103/µL, respectively, compared with the control groups, at 8.79±1.49fL and 270.29±61.82 x103/µL. These findings were not statistically significant. PDW values were found to be slightly high in patients with NPs, at 17.1±1.36 fL, compared with the control group, at 16.78±1.04 fL (p=0.075. But PCT values were found to be low in patients with NPs, at 0.21±0.065, compared with the control group, at 0.23±0.069 (p=0.044. This finding was statistically significant. Discussion: In our study, the MPV and PLT values were lower in patients with NPs, but the difference was not statistically significant. According to our findings, the use of MPV as an inflammation marker in patients with NPs does not seem to be reliable.

  15. Level Width Broaden Effect

    Institute of Scientific and Technical Information of China (English)

    ZHANG Jing-Shang

    2004-01-01

    In fitting the double-differential measurements thelevelwidth broadening effect should be taken into account properly due to Heisenberg uncertainty.Besides level width broadening effect the energy resolution in the measurements is also needed in this procedure.In general,the traditional normal Gaussian expansion is employed.However,the research indicates that to do so in this way the energy balance could not hold.For this reason,the deformed Gaussian expansion functions with exponential form for both the single energy point and continuous spectrum are introduced,with which the normalization and energy balance conditions could hold exactly in the analytical form.

  16. Platelet dynamics in three-dimensional simulation of whole blood.

    Science.gov (United States)

    Vahidkhah, Koohyar; Diamond, Scott L; Bagchi, Prosenjit

    2014-06-03

    A high-fidelity computational model using a 3D immersed boundary method is used to study platelet dynamics in whole blood. We focus on the 3D effects of the platelet-red blood cell (RBC) interaction on platelet margination and near-wall dynamics in a shear flow. We find that the RBC distribution in whole blood becomes naturally anisotropic and creates local clusters and cavities. A platelet can enter a cavity and use it as an express lane for a fast margination toward the wall. Once near the wall, the 3D nature of the platelet-RBC interaction results in a significant platelet movement in the transverse (vorticity) direction and leads to anisotropic platelet diffusion within the RBC-depleted zone or cell-free layer (CFL). We find that the anisotropy in platelet motion further leads to the formation of platelet clusters, even in the absence of any platelet-platelet adhesion. The transverse motion, and the size and number of the platelet clusters are observed to increase with decreasing CFL thickness. The 3D nature of the platelet-RBC collision also induces fluctuations in off-shear plane orientation and, hence, a rotational diffusion of the platelets. Although most marginated platelets are observed to tumble just outside the RBC-rich zone, platelets further inside the CFL are observed to flow with an intermittent dynamics that alters between sliding and tumbling, as a result of the off-shear plane rotational diffusion, bringing them even closer to the wall. To our knowledge, these new findings are based on the fundamentally 3D nature of the platelet-RBC interaction, and they underscore the importance of using cellular-scale 3D models of whole blood to understand platelet margination and near-wall platelet dynamics.

  17. An association of platelet indices with blood pressure in Beijing adults: Applying quadratic inference function for a longitudinal study.

    Science.gov (United States)

    Yang, Kun; Tao, Lixin; Mahara, Gehendra; Yan, Yan; Cao, Kai; Liu, Xiangtong; Chen, Sipeng; Xu, Qin; Liu, Long; Wang, Chao; Huang, Fangfang; Zhang, Jie; Yan, Aoshuang; Ping, Zhao; Guo, Xiuhua

    2016-09-01

    The quadratic inference function (QIF) method becomes more acceptable for correlated data because of its advantages over generalized estimating equations (GEE). This study aimed to evaluate the relationship between platelet indices and blood pressure using QIF method, which has not been studied extensively in real data settings.A population-based longitudinal study was conducted in Beijing from 2007 to 2012, and the median of follow-up was 6 years. A total of 6515 cases, who were aged between 20 and 65 years at baseline and underwent routine physical examinations every year from 3 Beijing hospitals were enrolled to explore the association between platelet indices and blood pressure by QIF method. The original continuous platelet indices were categorized into 4 levels (Q1-Q4) using the 3 quartiles of P25, P50, and P75 as a critical value. GEE was performed to make a comparison with QIF.After adjusting for age, usage of drugs, and other confounding factors, mean platelet volume was negatively associated with diastolic blood pressure (DBP) (Equation is included in full-text article.)in males and positively linked with systolic blood pressure (SBP) (Equation is included in full-text article.). Platelet distribution width was negatively associated with SBP (Equation is included in full-text article.). Blood platelet count was associated with DBP (Equation is included in full-text article.)in males.Adults in Beijing with prolonged exposure to extreme value of platelet indices have elevated risk for future hypertension and evidence suggesting using some platelet indices for early diagnosis of high blood pressure was provided.

  18. Terrace-Width Distributions (TWDs) of Touching Steps: Modification of the Fermion Analogy, with Implications for Measuring Step-Step Interactions on Vicinals

    Science.gov (United States)

    Einstein, T. L.; Sathiyanarayanan, Rajesh; Hamouda, Ajmi Bh.; Kim, Kwangmoo

    2010-03-01

    Using Monte Carlo simulations, we computefootnotetextRS, ABH, and TLE, Phys. Rev. B 80 (2009) 153415. the TWDs of surfaces in which steps can touch each other, forming multiple-atomic height steps, but cannot cross (no overhangs), and so inconsistent with the standard mapping to spinless fermions. Our numerical results show that the generalized Wigner distribution, with minor modifications at small step separations, gives a very good fit for TWDs of touching steps. (We also generate analytic results by generalizing results for extended fermions.footnotetextSiew-Ann Cheong and C.L. Henley, arXiv:0907.4228v1.) The interaction strength derived from the fit parameter indicates an effective attraction between steps, weakening the overall repulsion. The strength of this effective attraction decreases for larger mean-step separations and decreasing step-touching energies; describable via finite-size scaling. Hence, accurate extraction of the true repulsion strength requires multiple vicinalities.

  19. Platelet transfusion in chemotherapy patients: comparison of the effect of intravenous infusion pumps versus gravity transfusion.

    Science.gov (United States)

    Meess, A

    2015-01-01

    Platelet concentrates are given to patients suffering with severe thrombocytopenia usually by a gravity transfusion procedure. Increasing patient numbers that are in need of this treatment increase the pressure on hospital staff and space. In order to combat time issues, the use of medical devices such as intravenous infusion pumps are thought to be beneficial for time and simultaneously for safety in transfusion practices. By using infusion pumps, platelet concentrates can be transfused in less time and provide accurate volume measurements. Manufacturers of infusion pumps claim that these devices are safe to be used for blood products including platelet concentrates. However, published studies were performed on older models and newer devices are on the market now. The purpose of this study is to evaluate infusion pumps, which are claimed to be suitable for blood products and to investigate the impact the pumps had on platelets. Furthermore, the study revealed if the intravenous infusion pumps are safe to be used for platelet transfusion as claimed by manufacturers. A simulated transfusion was performed using the Carefusion Alaris GP Plus volumetric pump and Fresenius Kabi Volumat Agilia infusion pump. Samples were taken from expired platelet concentrates before and after passage through the pump. All samples were investigated for full blood count that included platelet count, mean platelet volume (MPV), platelet distribution width (PDW) and a plateletcrit (PCT). The samples were then centrifuged to achieve platelet-poor plasma and then tested for lactate dehydrogenase (LDH). A power calculation performed on the statistical power analysis program G*power indicated a requirement of 82 samples for a power of 80%. Statistical analysis was performed with the IBM SPSS statistic software. A paired sample t-test was used to calculate mean, standard deviation and P values for the infusion pumps used. The Wilcoxon Signed Rank Test was used to evaluate results that had a non

  20. 血小板系列参数对血小板减少性疾病的临床意义%Clinical Significance of Platelet Parameters to the Diseases on Platelet Reduce

    Institute of Scientific and Technical Information of China (English)

    李瑞珍

    2014-01-01

    目的:探讨血小板系列参数对血小板减少性疾病的临床意义。方法采用SysmexXE-5000血液分析仪分别对200例健康体检者及200例血小板减少性患者的血小板平均体积( MPV)、血小板分布宽度( PDW)、大血小板比率( P-LCR)及血小板比容( PCT)进行测定。结果血小板减少性患者与血小板正常人群比较,其血小板平均体积( MPV)、血小板分布宽度( PDW)、大血小板比率( P-LCR)及血小板比容( PCT)有不同程度的升高、轻度降低或显著降低,差异均有统计学意义。结论血小板系列参数分析可作为某些血小板减少性疾病鉴别诊断的初筛指标,对某些血小板减少性疾病患者的诊断和治疗具有重要参考价值。%Objective To investigate the clinical significance of platelet parameters to the diseases on platelet reduce. Methods SysmexXE-5000 blood analyzer respectively in 200 healthy subjects and 200 patients with thrombocytopenia, platelet mean volume of patients (MPV), platelet distribution width (PDW), platelet large cell ratio (P-LCR) and hematocrit (PCT) were measured. Results The thrombocytopenia compared the normal population it’ platelet ( MPV, average volume, platelet dis-tribution width ( PDW) , platelet large cell ratio ( P-LCR) and hematocrit ( PCT) were slightly decreased or decreased significant-ly, the differences were statistically significant. Conclusion The platelet parameter analysis can be used for some thrombocytope-nia in differential diagnosis of disease screening index, which has important reference value for some thrombocytopenia of diagnosis and treatment.

  1. Mean platelet volume (MPV predicts middle distance running performance.

    Directory of Open Access Journals (Sweden)

    Giuseppe Lippi

    Full Text Available Running economy and performance in middle distance running depend on several physiological factors, which include anthropometric variables, functional characteristics, training volume and intensity. Since little information is available about hematological predictors of middle distance running time, we investigated whether some hematological parameters may be associated with middle distance running performance in a large sample of recreational runners.The study population consisted in 43 amateur runners (15 females, 28 males; median age 47 years, who successfully concluded a 21.1 km half-marathon at 75-85% of their maximal aerobic power (VO2max. Whole blood was collected 10 min before the run started and immediately thereafter, and hematological testing was completed within 2 hours after sample collection.The values of lymphocytes and eosinophils exhibited a significant decrease compared to pre-run values, whereas those of mean corpuscular volume (MCV, platelets, mean platelet volume (MPV, white blood cells (WBCs, neutrophils and monocytes were significantly increased after the run. In univariate analysis, significant associations with running time were found for pre-run values of hematocrit, hemoglobin, mean corpuscular hemoglobin (MCH, red blood cell distribution width (RDW, MPV, reticulocyte hemoglobin concentration (RetCHR, and post-run values of MCH, RDW, MPV, monocytes and RetCHR. In multivariate analysis, in which running time was entered as dependent variable whereas age, sex, blood lactate, body mass index, VO2max, mean training regimen and the hematological parameters significantly associated with running performance in univariate analysis were entered as independent variables, only MPV values before and after the trial remained significantly associated with running time. After adjustment for platelet count, the MPV value before the run (p = 0.042, but not thereafter (p = 0.247, remained significantly associated with running

  2. Platelet matching for alloimmunized patients

    Institute of Scientific and Technical Information of China (English)

    S H.Hsu

    2010-01-01

    @@ Platelets play an essential role in blood coagulation,hemostasis and maintenance of vascular integrity.Platelets are utilized primarily to prevent or treat bleeding in thrombocytopenic patients and patients with impaired platelet production in the bone marrow and/or with dysfunctional platelets.In current practice,platelet transfusion begins with randomly selected platelet products:either pooled platelets prepared from whole blood derived platelets; or single donor platelets prepared by apheresis procedures.

  3. Changes of Platelet Indices in Juvenile Idiopathic Arthritis in Acute Phase and After Two Months Treatment

    Directory of Open Access Journals (Sweden)

    Marjan Vakili

    2016-05-01

    Full Text Available Background Various indices have been raised as predictors of activity and severity of juvenile idiopathic arthritis. Objectives This study was conducted to investigate the changes of platelet indices in acute phase and two months after treatment in these patients. Patients and Methods In a cohort study, platelet count, mean platelet volume (MPV, platelet distribution width (PDW, plateletcrit (PCT were evaluated in children referred to children’s medical center, Tehran due to juvenile idiopathic arthritis from March 2013 to March 2014 during the acute phase and two months after standard treatment. The statistical data were analyzed by SPSS 19 software, and the significance level was set as P < 0.05. Results In this study, 55 children (24 boys and 31 girls with mean ± SD age of 7.50 ± 3.35 years were studied. The mean ± SD value of platelet count was 441872.7 ± 151836.9 in the acute phase and reached 395418.2 ± 119601.6 two months after treatment (P = 0.01. The mean ± SD PCT in the acute phase of various subtypes of the disease was 0.32 ± 0.11, which reached 0.29 ± 0.10 after treatment (P = 0.09. However, the PDW range in different subtypes of the disease reached 13.4 ± 8.0 from 13.9 ± 2.9 and MPV reached 8.7 ± 0.9 from 8.8 ± 1.1 after treatment, but they were not significantly different from the results in the acute phase (P = 0.5. Conclusions Platelet count is one of the most remarkable indices in JIA. Evaluation of PCT can also help determine the severity of the inflammatory process in the follow-up and treatment process.

  4. Global synchronization of parallel processors using clock pulse width modulation

    Science.gov (United States)

    Chen, Dong; Ellavsky, Matthew R.; Franke, Ross L.; Gara, Alan; Gooding, Thomas M.; Haring, Rudolf A.; Jeanson, Mark J.; Kopcsay, Gerard V.; Liebsch, Thomas A.; Littrell, Daniel; Ohmacht, Martin; Reed, Don D.; Schenck, Brandon E.; Swetz, Richard A.

    2013-04-02

    A circuit generates a global clock signal with a pulse width modification to synchronize processors in a parallel computing system. The circuit may include a hardware module and a clock splitter. The hardware module may generate a clock signal and performs a pulse width modification on the clock signal. The pulse width modification changes a pulse width within a clock period in the clock signal. The clock splitter may distribute the pulse width modified clock signal to a plurality of processors in the parallel computing system.

  5. Are Global Coagulation and Platelet Parameters Useful Markers for Predicting Late-Onset Neonatal Sepsis?.

    Science.gov (United States)

    Lu, Qi; Duan, Hongmei; Yu, Jialin; Yao, Yao

    2016-01-01

    Diagnosis of neonatal sepsis is difficult because of the nonspecific nature of the clinical presentation. Inflammation and coagulation can activate each other. Coagulation activation can occur in the early phase of sepsis. The main purposes of this study were to investigate the value of platelet parameters and coagulation parameters in predicting neonatal sepsis. The study included 650 patients: 490, Group I (330 proven and 160 clinical sepsis cases), and 160, Group II (control group). Platelet count (PLT), mean platelet volume (MPV), platelet distribution width (PDW), thrombocytocrit, prothrombin time (PT), and activated partial thromboplastin time (APTT) were measured. The parameters were determined before diagnosis of sepsis. Receiver-operating characteristic (ROC) curves were analyzed to determine the optimal thresholds. The optimum cutoff value, sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were calculated for each potential marker. The MPV, PDW, PT, and CRP values were found to be increased while PLT decreased significantly in sepsis patients. ROC curve analysis showed that PT and PLT were better than PDW and MPV for the diagnosis of sepsis. Further, combining PT (17.85 s) and CRP (8.5 mg/L) can enhance the diagnostic accuracy of sepsis, with a sensitivity, specificity, PPV, and NPV of 77.9, 83.1, 58.2, and 92.6%, respectively. PT has a potential to be an additional indicator for neonatal sepsis, the combined use of PT and other markers such as CRP should be considered in the early diagnosis of neonatal sepsis.

  6. Evaluation of the immature platelet fraction in the diagnosis and prognosis of childhood immune thrombocytopenia.

    Science.gov (United States)

    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

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

    Institute of Scientific and Technical Information of China (English)

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

    2015-01-01

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

  8. Clinical application of radiolabelled platelets

    Energy Technology Data Exchange (ETDEWEB)

    Kessler, C. (Medical Univ. Lubeck, Lubeck (DE))

    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.

  9. Índice de anisocitose eritrocitária (RDW: diferenciação das anemias microcíticas e hipocrômicas Red blood cell distribution width (RDW: differentiation of microcytic and hypochromic anemias

    Directory of Open Access Journals (Sweden)

    Januária F. Matos

    2008-04-01

    Full Text Available A anemia ferropriva, talassemia menor e anemia de doença crônica são as anemias microcíticas e hipocrômicas mais comuns em nosso meio. O diagnóstico diferencial das referidas anemias é de grande importância clínica; contudo, muitas vezes é complexo em virtude de concomitância de doenças, além de demandar tempo e apresentar custos significativos. Com o propósito de conferir maior simplicidade e eficiência ao diagnóstico diferencial destas anemias, o uso de índices derivados de modernos contadores automáticos tem sido sugerido. Entre estes, pode ser citado o índice de anisocitose eritrocitária (RDW, que indica o grau de variabilidade do tamanho das hemácias. Neste estudo, o poder de discriminação deste índice quanto ao tipo de anemia microcítica e hipocrômica foi avaliado em um grupo de 159 pacientes sabidamente portadores de um quadro de anemia causado por deficiência de ferro, beta talassemia menor ou uma anemia de doença crônica. Não foi observada diferença significativa para o RDW entre os três grupos de anemias microcíticas, indicando não ser este índice uma ferramenta útil para a diferenciação entre anemia ferropriva, beta talassemia menor e anemia de doença crônica.Iron deficiency anemia, the thalassemia trait and chronic disease anemia are the most common microcytic and hypochromic anemias in the Brazilian population. Differential diagnosis of these anemias is of great clinical importance however, frequently, it is complex due to coexistence of diseases, as well as being time consuming and expensive. In order to simplify and increase efficiently of checking the differential diagnoses of these anemias, the use of indexes derived from modern blood cell counters has been suggested. Among them, is the index called red blood cell distribution width which indicates the variability in red blood cell size. In this study, the discriminative power of the red blood cell distribution width in differentiating

  10. Progress in clinical application of red blood cell distribution width in cardiovascular diseases%红细胞分布宽度在心血管疾病的临床应用进展

    Institute of Scientific and Technical Information of China (English)

    王钢; 华琦

    2015-01-01

    红细胞分布宽度(RDW)是测定血液循环中红细胞体积大小是否具有均一性、形态可变性和大小变异性的一个指标,常结合红细胞平均体积用于诊断贫血。研究表明RDW升高可以在心血管疾病的预测及诊断中提供有价值的线索。本篇综述介绍RDW在心血管疾病中的临床应用。%The red blood cell distribution width (RDW) is a measure of the variation of red blood cell (RBC, also known as erythrocytes), which is typically used in combination with mean corpuscular volume to diagnose anemia. Recently, a number of studies have shown that an increased RDW is a strong and independent predictor of prognosis in cardiovascular disease (CVD). Although the mechanism is still unclear, nevertheless, RDW is an easy, inexpensive, and routinely reported test which might supply diagnostic and prognostic information for patients with CVD. This article reviewed the promising progress in RDW application in cardiovascular disease.

  11. Research progress on the relationship between red cell distribution width and liver disease%红细胞分布宽度与肝脏疾病的关系

    Institute of Scientific and Technical Information of China (English)

    林青; 石建凤; 王莉

    2015-01-01

    Red cell distribution width (RDW) is an objective indicator of red blood cell (RBC) heterogeneity which reflects size variability of RBC.Rise of RDW associates many disease,especially with cardiovascular disease.The association of RDW and liver disease focuses on the relationship with severity of HBV-associated liver disease and nonalcoholic fatty liver disease and with stage of liver fibrosis.Research progresses on these aspects are reviewed in this paper.%红细胞分布宽度(RDW)是红细胞异质性的客观指标,反映了红细胞大小不均一性.RDW升高与许多疾病相关,特别是心血管疾病,而与肝脏疾病的关系研究主要集中于与慢性HBV感染相关的疾病和非酒精性脂肪性肝病纤维化程度以及疾病严重程度的相关性上.此文就RDW与上述肝脏疾病相关性研究的进展进行综述.

  12. Platelets and hemostasis

    Directory of Open Access Journals (Sweden)

    M. A. Panteleev

    2014-09-01

    Full Text Available Platelets are anuclear cell fragments playing important role in hemostasis, termination of bleeding after damage, as well as in pathological thrombus formation. The main action of platelets is the formation of aggregates, overlapping the injury. They obtained the ability to aggregate by the transition process called activation. Despite the relatively simple and definite function platelet structure is very difficult: they have almost a full set of organelles, including the endoplasmic reticulum, mitochondria and other entities. When activated platelets secrete various granules interact with plasma proteins and red blood cells and other tissues. Their activation is controlled by multiple receptors and complex signaling cascades. In this review platelet structure, mechanisms of its functioning in health and disease, diagnostic methods of platelet function and approaches to their correction were considered. Particular attention will be given to those areas of the science of platelets, which still lay hidden mysteries.

  13. Fast Rendering for Great Width Stereo Image Pair Based on Distributed Rendering%基于分布式绘制的大幅面立体像对快速浏览技术

    Institute of Scientific and Technical Information of China (English)

    刘涛; 谢剑薇; 龚雪晶; 赵兴国

    2012-01-01

    针对当前影像数据存储格式不能适应海量影像数据快速访问的情况,研究设计了大幅面立体像对的逻辑四叉树存储格式,并通过立体像对的逻辑四叉树剖分算法把普通格式的立体像对格式快速转换成逻辑四叉树存储格式。由于单机显示无法满足大幅面立体像对的高分辨率、高沉浸感的显示,因此系统研究了大幅面立体像对快速浏览的分布式结构,包括硬件选择、分布式策略和通信方式等方面。由于当前分布式网络不足以支持大规模数据的实时传输,根据帧相关性原理,研究提出了大幅面立体像对的分布式缓冲机制。最后通过实验证明该方法能够实现大幅面立体像对的实时浏览。%The current image data format cannot fit the fast access of the massive image data, so the logistic quad-tree structure has been designed for the large scale stereo image pair, and the ordinary form of stereo image pair can be fast changed into logistic quad-tree structure ones through the split method of the logistic quad-tree structure. The single machine display cannot meet the high resolution and high immersion display of the large scale stereo image pair, so the distributed structure has been studied to the fast browsing of the large scale stereo image pair, including hardware choice, distributed strategy, communications method, and so on. Because the current distributed network is insufficient to support the real-time transmission of the large-scale data, the data management mechanism has been proposed for the large scale stereo image pair according to the flame relevant principle, including distributed cache mechanism and fast access algorithm. The experiment proves that the application above technology to the fast rendering for the great width stereo image pair has realized real-time roams in the large screen stereo display.

  14. Probabilistic Analysis of Crack Width

    Directory of Open Access Journals (Sweden)

    J. Marková

    2000-01-01

    Full Text Available Probabilistic analysis of crack width of a reinforced concrete element is based on the formulas accepted in Eurocode 2 and European Model Code 90. Obtained values of reliability index b seem to be satisfactory for the reinforced concrete slab that fulfils requirements for the crack width specified in Eurocode 2. However, the reliability of the slab seems to be insufficient when the European Model Code 90 is considered; reliability index is less than recommended value 1.5 for serviceability limit states indicated in Eurocode 1. Analysis of sensitivity factors of basic variables enables to find out variables significantly affecting the total crack width.

  15. A closer look at the "characteristic" width of molecular cloud filaments

    CERN Document Server

    Panopoulou, G V; Skalidis, R; Tassis, K; Andrews, J J

    2016-01-01

    Filaments in Herschel molecular cloud images are found to exhibit a "characteristic width". This finding is in tension with spatial power spectra of the data, which show no indication of this characteristic scale. We demonstrate that this discrepancy is a result of the methodology adopted for measuring filament widths. First, we perform the previously used analysis technique on artificial scale-free data, and obtain a peaked width distribution of filament-like structures. Next, we repeat the analysis on three Herschel maps and reproduce the narrow distribution of widths found in previous studies $-$ when considering the average width of each filament. However, the distribution of widths measured at all points along a filament spine is broader than the distribution of mean filament widths, indicating that the narrow spread (interpreted as a "characteristic" width) results from averaging. Furthermore, the width is found to vary significantly from one end of a filament to the other. Therefore, the previously ide...

  16. Platelet profile is associated with clinical complications in patients with vivax and falciparum malaria in Colombia

    Directory of Open Access Journals (Sweden)

    Edgar Leonardo Martínez-Salazar

    2014-06-01

    Full Text Available Introduction Thrombocytopenia is a common complication in malaria patients. The relationship between abnormal platelet profile and clinical status in malaria patients is unclear. In low and unstable endemic regions where vivax malaria predominates, the hematologic profiles of malaria patients and their clinical utility are poorly understood. The aim of this study was to characterize the thrombograms of malaria patients from Colombia, where Plasmodium vivax infection is common, and to explore the relationship between thrombograms and clinical status. Methods Eight hundred sixty-two malaria patients were enrolled, including 533 (61.8% patients infected with Plasmodium falciparum, 311 (36.1% patients infected with Plasmodium vivax and 18 (2.1% patients with mixed infections. Results The most frequently observed changes were low platelet count (PC and high platelet distribution width (PDW, which were observed in 65% of patients; thrombocytopenia with <50,000 platelets/µL was identified in 11% of patients. Patients with complications had lower PC and plateletcrit (PT and higher PDW values. A higher risk of thrombocytopenia was identified in patients with severe anemia, neurologic complications, pulmonary complications, liver dysfunction, renal impairment and severe hypoglycemia. The presence of thrombocytopenia (<150,000 platelets/µL was associated with a higher probability of liver dysfunction. Conclusions Young age, longer duration of illness and higher parasitemia are associated with severe thrombocytopenia. Our study showed that thrombocytopenia is related to malaria complications, especially liver dysfunction. High PDW in patients with severe malaria may explain the mechanisms of thrombocytopenia that is common in this group of patients.

  17. Effect of Severe Maternal Iron Deficiency Anemia on Neonatal Platelet Indices.

    Science.gov (United States)

    Basu, Sriparna; Kumar, Naveen; Srivastava, Ragini; Kumar, Ashok

    2015-12-01

    To evaluate the effect of maternal iron deficiency anemia (IDA) on fetal thrombopoiesis. In this prospective observational study, maternal and cord blood iron status parameters (serum iron, serum ferritin, total iron-binding capacity, and transferrin saturation), and platelet indices, such as, absolute platelet count (APC), mean platelet volume (MPV), platelet distribution width (PDW) and plateletcrit, were estimated in a convenient sample of 142 mothers with IDA (hemoglobin neonates at term gestation. Mothers with antenatal thrombocytopenia, infections, inflammatory conditions, pregnancy-induced hypertension and neonates with perinatal asphyxia, sepsis and congenital malformations were excluded. For statistical analysis, the IDA group was further subdivided into mild-to-moderate (hemoglobin 7-10.9 g/dl) and severe (hemoglobin anemia. Cord blood APC and PDW were comparable between non-anemic and mild-to-moderate anemic mothers (242,550 ± 54,320/μL vs. 235,260 ± 34,620/μL for APC and 16.2 ± 1.4 vs. 16.4 ± 1.8 fl for PDW, respectively), but in severe IDA group, cord blood APC and PDW were significantly lower (74,520 ± 12,380/μL and 17.8 ± 2.1 fl, respectively, p neonates had a platelet count Neonates born to mothers with severe IDA had moderate thrombocytopenia with increased PDW, though no change was observed in MPV and plateletcrit. Further studies should be carried out to identify the cause and consequences of this observation.

  18. Bounding the Higgs boson width through interferometry.

    Science.gov (United States)

    Dixon, Lance J; Li, Ye

    2013-09-13

    We study the change in the diphoton-invariant-mass distribution for Higgs boson decays to two photons, due to interference between the Higgs resonance in gluon fusion and the continuum background amplitude for gg→γγ. Previously, the apparent Higgs mass was found to shift by around 100 MeV in the standard model in the leading-order approximation, which may potentially be experimentally observable. We compute the next-to-leading-order QCD corrections to the apparent mass shift, which reduce it by about 40%. The apparent mass shift may provide a way to measure, or at least bound, the Higgs boson width at the Large Hadron Collider through "interferometry." We investigate how the shift depends on the Higgs width, in a model that maintains constant Higgs boson signal yields. At Higgs widths above 30 MeV, the mass shift is over 200 MeV and increases with the square root of the width. The apparent mass shift could be measured by comparing with the ZZ* channel, where the shift is much smaller. It might be possible to measure the shift more accurately by exploiting its strong dependence on the Higgs transverse momentum.

  19. 山东金刚石晶体中氮片晶的分布特征及其表面微形貌%Distribution Characteristics and Surface Microtopography of Nitrogen Platelets in Diamond Crystals from Shandong Province,China

    Institute of Scientific and Technical Information of China (English)

    张健; 陈华; 陆太进; 丘志力; 魏然

    2011-01-01

    In order to study the distribution characteristics of nitrogen platelets in diamond crystals from Shandong Province,China,116 pieces of gem quality diamond crystal samples are investigated by using FTIR.The surface microstructures related to the nitrogen platelets are observed by differential interference microscope.The results show that 80.2% of the diamond samples contain nitrogen platelets.The stripe-like etch figures parallel to directions on {111} planes are discovered on the surfaces of several brown octahedral diamond samples.These etch figures lie parallel to each other and vary in size.The microanalysis of the {111} planes show that there are stronger IR absorption peaks at 1359-1375cm-1 in the diamond samples,revealing the existence of huge quantities of nitrogen platelets.Judging from their appearances and IR spectra,the formation of the stripe-like etch figures parallel to directions on {111} planes may result from selective etching of the platelets.%为研究山东蒙阴金伯利岩型金刚石晶体中氮片晶的分布特征,采用红外光谱仪对116粒宝石级金刚石晶体样品中的氮片晶进行分析,并采用微分干涉显微镜观察氮片晶在金刚石表面所具有的物理化学性质及其表面微细结构。结果表明,80.2%的金刚石样品中具有氮片晶;在个别浅褐色、八面体金刚石样品{111}面上观察到平行于[100]晶带方向的长条状蚀像,这些蚀像相互平行,大小不等。显微红外光谱对具长条状蚀像的金刚石样品{111}面的测试结果表明,该类晶体均具有较强的氮片晶的吸收峰(1359~1375cm-1)。综合浅褐色、八面体金刚石样品的红外光谱及其表面微形貌特征,推测长条状蚀像是由氮片晶的出露点受优先选择性腐蚀而致。

  20. Combined Value of Red Blood Cell Distribution Width and Global Registry of Acute Coronary Events Risk Score for Predicting Cardiovascular Events in Patients with Acute Coronary Syndrome Undergoing Percutaneous Coronary Intervention.

    Directory of Open Access Journals (Sweden)

    Na Zhao

    Full Text Available Global Registry of Acute Coronary Events (GRACE risk score and red blood cell distribution width (RDW content can both independently predict major adverse cardiac events (MACEs in patients with acute coronary syndrome (ACS. We investigated the combined predictive value of RDW and GRACE risk score for cardiovascular events in patients with ACS undergoing percutaneous coronary intervention (PCI for the first time. We enrolled 480 ACS patients. During a median follow-up time of 37.2 months, 70 (14.58% patients experienced MACEs. Patients were divided into tertiles according to the baseline RDW content (11.30-12.90, 13.00-13.50, 13.60-16.40. GRACE score was positively correlated with RDW content. Multivariate Cox analysis showed that both GRACE score and RDW content were independent predictors of MACEs (hazard ratio 1.039; 95% confidence interval [CI] 1.024-1.055; p < 0.001; 1.699; 1.294-2.232; p < 0.001; respectively. Furthermore, Kaplan-Meier analysis demonstrated that the risk of MACEs increased with increasing RDW content (p < 0.001. For GRACE score alone, the area under the receiver operating characteristic (ROC curve for MACEs was 0.749 (95% CI: 0.707-0.787. The area under the ROC curve for MACEs increased to 0.805 (0.766-0.839, p = 0.034 after adding RDW content. The incremental predictive value of combining RDW content and GRACE risk score was significantly improved, also shown by the net reclassification improvement (NRI = 0.352, p < 0.001 and integrated discrimination improvement (IDI = 0.023, p = 0.002. Combining the predictive value of RDW and GRACE risk score yielded a more accurate predictive value for long-term cardiovascular events in ACS patients who underwent PCI as compared to each measure alone.

  1. Effects of combined therapy of traditional Chinese medicine and western medicine on platelets, coagulative functions and inflammatory cytokines with ulcerative colitis

    Institute of Scientific and Technical Information of China (English)

    Yun-Xia Lei; Lei He; Hao Sheng; Xin Liu

    2016-01-01

    Objective:To explore the effects of combined therapy of traditional Chinese medicine and western medicine on platelets, coagulative functions and inflammatory cytokines in patients with ulcerative colitis (UC). Methods:A total of 267 patients with UC were collected. 137 patients were treated with combined therapy of traditional Chinese medicine and western medicine as experimental group and 130 patients were treated with only western medicine as controls. Platelet count, coagulation function indexes and inflammatory cytokines were measured before and 15 d after the treatment. Results:No significantly differences were found in all indexes before treatment between two groups. After different treatments, platelet count (PLT), platelet distribution width (PDW) were significantly decreased in both groups, but mean platelet volumn (MPV) were significantly increased than before treatment. PLT and PDW were significantly lower and MPV were significantly higher in experimental group than control group. Fibrinogen (Fib) and D-dimer (DD) decreased significantly after treatment. Fib and DD in experimental group were significantly lower than controls. No significantly differences were found in activated partial thromboplastin time (APTT) and prothrobin time (PT). Tumor necrosisi factor-α(TNF-α), interleukin-6 (IL-6) and interleukin-8 (IL-8) decreased significantly in both group after treatment. TNF-α, IL-6 and IL-8 were significantly lower in experimental group than controls. Conclusion:Combined therapy of traditional Chinese medicine and western medicine can more effectively improve the cogulation, fibrinolysis and inflammation in patients with UC than only western medicine therapy.

  2. Correlation between interalar width and intercommisural width against mesiodistal width of central upper incisor in Buginese tribe

    Directory of Open Access Journals (Sweden)

    Bahruddin Thalib

    2016-04-01

    Full Text Available Various types of anatomical landmarks of the face should match its proportions with the size of the teeth which is the interalar width, intercomissural width, interpupillary width, Intercanthal width, and byzigomatic width. Some of face landmarks can be used as a guide in the selection of anterior teeth in complete denture, especially if the pre extraction record such as radiography image, extracted teeth, model study, the remaining teeth, face shape, and the shape of the curved jaw have been lost. The objective of this study was to evaluate the correlation between interalar width and intercommisural width against mesiodistal incisivus centralis width in a group of Buginese tribe. Ninety nine Buginese tribe subjects aged 17-25 were selected. The interalar width, intercommisural width, and mesiodistal incisor centralis teeth were measured using caliper about three times for accuracy and precision. Mean of interalar width and mesiodistal incisor centralis maxilla width in males more width than females (p0.05. The degree of correlation between interalar width against mesiodistal incisor centralis maxilla width was 0.030, -0.246, 0,225 in Buginese tribe, males, and females (p>0.05. : The degree of correlation between intercommisural width against  mesiodistal incisor centralis maxilla width in Buginese tribe was 0,054, 0,013, 0,153 in Buginese tribe, males, and females (p>0.05. The degree of correlation between interalar width and intercommisural width was 0.301 and 0.356 in Buginese tribe and males (p0.05. In conclusion, there is no significant correlation between interalar width and intercommisural width against mesiodistal incisor centralis maxilla width in a group of Buginese tribe. Interalar width and intercommisural width  directly proportional to mesiodistal incisor centralis maxilla in a group of Buginese tribe. Interalar width and intercommisural width  inversely proportional to mesiodistal incisor centralis maxilla in males and directly

  3. Biological width: No violation zone

    Directory of Open Access Journals (Sweden)

    Ashu Sharma

    2012-01-01

    Full Text Available Maintenance of gingival health is one of the keys for the longevity of teeth, as well as for the longevity of restorations. The concept of Biologic width has been widely described by periodontists and restorative dentists. An adequate understanding of relationship between periodontal tissues and restorative dentistry is paramount to ensure adequate form, function and esthetics, and comfort of the dentition. While most clinicians are aware of this important relationship, uncertainty remains regarding specific concepts such as biologic width and indications and applications of surgical crown lengthening. These violations lead to complications like gingival inflammation, alveolar bone loss and improper fit of the restorative component. This review gives the wide aspect of the complex question of biologic width and represents an attempt to answer some of the demands in relation to it. The article also discusses the possible methods to assess biologic width, problems that occur after improper margin placement in the periodontium and the alternative procedures for prevention of biological width violation.

  4. 红细胞分布宽度和白细胞水平与冠心病的关系%Relationship of red blood cell distribution width and white blood cell count with coronary heart disease

    Institute of Scientific and Technical Information of China (English)

    孙洁静; 刘德平; 李华; 李辉; 张妮

    2015-01-01

    目的 观察红细胞分布宽度和白细胞水平与冠心病及冠状动脉病变的关系. 方法 选择行冠状动脉造影术患者590例,根据冠状动脉造影术结果分为冠心病组383例和对照组207例,并按冠状动脉病变支数将冠心病组分为不同的亚组,计算冠状动脉病变Gensini评分,比较各组间红细胞分布宽度和白细胞水平的差异,以及分析其与冠状动脉病变程度的相关性. 结果 冠心病组红细胞分布宽度和白细胞水平分别为(13.06±0.57)%、(6.33±1.56)×109/L,明显高于对照组(12.63±0.49)%、(5.86±1.29)×109/L(t=9.771、3.728,均P=0.000),并随着冠状动脉病变支数的增加而升高(F=51.454、7.544,均P=0.000),且与冠状动脉Gensini评分呈正相关(r=0.414、0.111,P=0.000、0.030);红细胞分布宽度与白细胞水平呈正相关(r=0.108,P=0.009).红细胞分布宽度对冠心病的预测价值进行受试者工作特征曲线(ROC)分析结果显示,红细胞分布宽度的界值为12.75%,ROC曲线下面积为0.723(95% CI:0.680~0.765),诊断的敏感度为67.6%,特异度为65.2%. 结论 红细胞分布宽度和白细胞水平在冠心病患者中明显升高,且与冠状动脉严重程度呈正相关,是冠心病的独立预测因子.%Objective To observe the relationship of the red blood cell distribution width and white blood cell count with coronary heart disease and coronary artery lesions.Methods Totally 590 patients undergoing coronary angiography were selected and divided into two groups based on the results of coronary angiography:coronary heart disease group (n=383) and control group (n=207).Based on the number of coronary lesions,patients in coronary heart disease were divided into different subgroup.The Gensini scores of coronary lesions were assessed.The differences in red blood cell distribution and white blood cell count were compared among different groups,and the correlations of coronary lesions with red blood cell distribution

  5. A numerical analysis model for the interpretation of in vivo platelet consumption data.

    Directory of Open Access Journals (Sweden)

    Ted S Strom

    Full Text Available Unlike anemias, most thrombocytopenias cannot be separated into those due to impaired production and those due to accelerated consumption. While rapid clearance of labeled platelets from the bloodstream can be followed in thrombocytopenic individuals, no model exists for quantitatively inferring from autologous or allogeneic platelet consumption data what changes in random consumption, lifespan dependent consumption, and platelet production rate may have caused the thrombocytopenia. Here we describe a numerical analysis model which resolves these issues. The model applies three parameter values (a random consumption rate constant, a lognormally-distributed platelet lifespan, and the standard deviation of the latter to a matrix comprising a series of platelet cohorts which are sequentially produced and fractionally consumed in a series of time intervals. The cohort platelet counts achieved after equilibration of production and consumption both enumerate the population age distribution and sum to the population platelet count. Continued platelet consumption after production is halted then serves to model in vivo platelet consumption data, with consumption rate in the first such interval defining the equilibrium platelet production rate. We use a least squares fitting procedure to find parameter values which best fit observed platelet consumption data obtained in WT and thrombocytopenic WASP(- mice. Equilibrium platelet age distributions are then 'grafted' into the matrix to allow modeling of the consumption of WT platelets in WASP(- recipients, and vice versa. The optimal parameter values obtained indicate that random WT platelet consumption accounts for a larger fraction of platelet turnover than was previously suspected. Platelet WASP deficiency accelerates random consumption, and a trans effect of recipient WASP deficiency contributes to this. Application of the model to clinical data will allow distinctions to be made between thrombocytopenias

  6. Functional alterations of human platelets following indium-111 labelling using different incubation media and labelling agents

    Energy Technology Data Exchange (ETDEWEB)

    Isaka, Yoshinari; Imaizumi, Masatoshi (Osaka National Hospital (Japan). Dept. of Cardiovascular Medicine and Radiological Science); Kimura, Kazufumi (Osaka Univ. (Japan). Dept. of Nuclear Medicine); Matsumoto, Masayasu; Kamada, Takenobu (Osaka Univ. (Japan). 1. Dept. of Internal Medicine)

    1991-05-01

    Human platelets were labelled in the absence of presence of plasma using {sup 111}In-labelled oxine sulphate, tropolone or 2-mercaptopyridine-N-oxide (MPO). Under in vitro and in vivo conditions, platelet functions were evaluated by measuring their aggregability, survival, recovery and early distribution. High labelling efficiency was achieved in saline labelling, whereas with plasma labelling, it was necessary to concentrate the platelet-rich plasma to 4.8x10{sup 6} platelets/{mu}l. The aggregation of platelets labelled in plasma or saline was compared with that of controls; platelets labelled in saline showed lower aggregability in 2 {mu}M ADP but not in 5 {mu}M ADP nor with collagen. No significant differences in platelet survival and recovery were noted between platelets labelled in plasma and those labelled in saline. Our results indicate that partial loss of ADP aggregability in vitro does not influence the in vivo viability of platelets labelled in saline. Scintigraphic studies showed that platelets labelled in a saline medium were temporarily sequestrated in the liver but not in the spleen or heart. Thus, platelet labelling in saline does not affect platelet function adversely, but platelets labelled in plasma are more desirable for assessing the early distribution of platelets in the reticuloendothelial system. (orig.).

  7. Platelet Dynamics in Three-Dimensional Simulation of Whole Blood

    OpenAIRE

    Vahidkhah, Koohyar; Diamond, Scott L.; Bagchi, Prosenjit

    2014-01-01

    A high-fidelity computational model using a 3D immersed boundary method is used to study platelet dynamics in whole blood. We focus on the 3D effects of the platelet-red blood cell (RBC) interaction on platelet margination and near-wall dynamics in a shear flow. We find that the RBC distribution in whole blood becomes naturally anisotropic and creates local clusters and cavities. A platelet can enter a cavity and use it as an express lane for a fast margination toward the wall. Once near the ...

  8. 红细胞分布宽度与慢性心力衰竭死亡率的Meta分析%A Meta-analysis on relationship between red cell distribution width and mortality of chronic heart failure

    Institute of Scientific and Technical Information of China (English)

    毛燕; 张国荣

    2013-01-01

    Objective To investigate the predictive value of red cell distribution width (RDW) to the mortality of chronic heart failure (CHF). Methods The databases of PubMed, Embase and CNKI were retrieved to collect the studies about the relationship between RDW and the mortality of CHF. The hazard ratio (HR) and 95%confidence interval (CI) of the mortality of CHF were calculated by using Stata12.0 software. Results There were totally 6 studies included involved 13 502 cases. The analysis on homogeneity showed that all eligible studies had heterogeneity (I2=79.9%, P<0.001). The combined HR was 1.18 (95%CI:1.10-1.25, P<0.001) after using random effect model. Conclusion RDW is an index for predicting the mortality of CHF.%目的探讨红细胞分布宽度(RDW)对预测慢性心力衰竭死亡率的价值。方法检索PubMed、Embase、CNKI数据库中所有论述RDW与慢性心衰死亡率队列研究的文献,使用Stata12.0软件计算合并死亡率的风险比(HR)和95%可信区间(95%CI)。结果共纳入相关文献6篇,累计样本量13502例。对入选文献进行一致性检验,文献间具有异质性(I2=79.9%,P<0.001),采用随机效应模型合并显示高水平RDW慢性心力衰竭患者死亡风险更高(HR=1.18,95%CI:1.10~1.25,P<0.001)。结论RDW是预测慢性心力衰竭死亡率的指标。

  9. Platelet alloimmunization after transfusion

    DEFF Research Database (Denmark)

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

    1997-01-01

    BACKGROUND AND OBJECTIVES: The frequency of platelet-specific antibodies after one series of blood transfusions has not been reported, and in multiply transfused patients is controversial. MATERIALS AND METHODS: We studied the frequency of alloimmunization against platelet antigens in 117 patient...

  10. Flavanols and Platelet Reactivity

    Directory of Open Access Journals (Sweden)

    Debra A. Pearson

    2005-01-01

    Full Text Available Platelet activity and platelet-endothelial cell interactions are important in the acute development of thrombosis, as well as in the pathogenesis of cardiovascular disease. An increasing number of foods have been reported to have platelet-inhibitory actions, and research with a number of flavanol-rich foods, including, grape juice, cocoa and chocolate, suggests that these foods may provide some protection against thrombosis. In the present report, we review a series of in vivo studies on the effects of flavanol-rich cocoa and chocolate on platelet activation and platelet-dependent primary hemostasis. Consumption of flavanol-rich cocoa inhibited several measures of platelet activity including, epinephrine- and ADP-induced glycoprotein (GP IIb/IIIa and P-Selectin expression, platelet microparticle formation, and epinephrine-collagen and ADP-collagen induced primary hemostasis. The epinephrine-induced inhibitory effects on GP IIb/IIIa and primary hemostasis were similar to, though less robust than those associated with the use of low dose (81 mg aspirin. These data, coupled with information from other studies, support the concept that flavanols present in cocoa and chocolate can modulate platelet function through a multitude of pathways.

  11. Platelet activation and aggregation

    DEFF Research Database (Denmark)

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

    2013-01-01

    This study introduces a new laboratory model of whole blood platelet aggregation stimulated by endogenously generated thrombin, and explores this aspect in haemophilia A in which impaired thrombin generation is a major hallmark. The method was established to measure platelet aggregation initiated...

  12. Gasotransmitters and platelets.

    Science.gov (United States)

    Truss, Nicola J; Warner, Timothy D

    2011-11-01

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

  13. Alloimmune refractoriness to platelet transfusions.

    Science.gov (United States)

    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).

  14. Platelet function in dogs

    DEFF Research Database (Denmark)

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

    2007-01-01

    Cairn Terriers, 10 Boxers, and 11 Labrador Retrievers) were included in the study. Platelet function was assessed by whole-blood aggregation with ADP (1, 5, 10, and 20 µM) as agonist and by PFA-100 using collagen and epinephrine (Col + Epi) and Cpæ + ADP as agonists. Plasma thromboxane B2 concentration......Background: Clinical studies investigating platelet function in dogs have had conflicting results that may be caused by normal physiologic variation in platelet response to agonists. Objectives: The objective of this study was to investigate platelet function in clinically healthy dogs of 4...... different breeds by whole-blood aggregometry and with a point-of-care platelet function analyzer (PFA-100), and to evaluate the effect of acetylsalicylic acid (ASA) administration on the results from both methods. Methods: Forty-five clinically healthy dogs (12 Cavalier King Charles Spaniels [CKCS], 12...

  15. Cisplatin triggers platelet activation.

    Science.gov (United States)

    Togna, G I; Togna, A R; Franconi, M; Caprino, L

    2000-09-01

    Clinical observations suggest that anticancer drugs could contribute to the thrombotic complications of malignancy in treated patients. Thrombotic microangiopathy, myocardial infarction, and cerebrovascular thrombotic events have been reported for cisplatin, a drug widely used in the treatment of many solid tumours. The aim of this study is to explore in vitro cisplatin effect on human platelet reactivity in order to define the potentially active role of platelets in the pathogenesis of cisplatin-induced thrombotic complications. Our results demonstrate that cisplatin increases human platelet reactivity (onset of platelet aggregation wave and thromboxane production) to non-aggregating concentrations of the agonists involving arachidonic acid metabolism. Direct or indirect activation of platelet phospholipase A(2) appears to be implicated. This finding contributes to a better understanding of the pathogenesis of thrombotic complications occurring during cisplatin-based chemotherapy.

  16. Platelet function in dogs

    DEFF Research Database (Denmark)

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

    2007-01-01

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

  17. Average radiation widths and the giant dipole resonance width

    Energy Technology Data Exchange (ETDEWEB)

    Arnould, M.; Thielemann, F.K.

    1982-11-01

    The average E1 radiation width can be calculated in terms of the energy Esub(G) and width GAMMAsub(G) of the Giant Dipole Resonance (GDR). While various models can predict Esub(G) quite reliably, the theoretical situation regarding ..lambda..sub(G) is much less satisfactory. We propose a simple phenomenological model which is able to provide GAMMAsub(G) values in good agreement with experimental data for spherical or deformed intermediate and heavy nuclei. In particular, this model can account for shell effects in GAMMAsub(G), and can be used in conjunction with the droplet model. The GAMMAsub(G) values derived in such a way are used to compute average E1 radiation widths which are quite close to the experimental values. The method proposed for the calculation of GAMMAsub(G) also appears to be well suited when the GDR characteristics of extended sets of nuclei are required, as is namely the case in nuclear astrophysics.

  18. Predictive value of red cell distribution width in aged patients with community acquired pneumonia%红细胞分布宽度对老年社区获得性肺炎预后的探讨

    Institute of Scientific and Technical Information of China (English)

    陈小军; 张泓

    2015-01-01

    目的:探讨红细胞分布宽度( red cell distribution width, RDW)对老年社区获得性肺炎( community acquired pneumonia, CAP)预后的预测价值。方法回顾性分析安徽医科大学第一附属医院急诊内科及急诊重症监护室205例老年CAP患者。根据入院时RDW将患者分为4组,对比各组间相关指标( CURB-65计分、器官衰竭及ICU入住率、住院天数、30 d死亡率)的差异,并就RDW对老年CAP住院患者死亡预测价值进行统计学分析。结果 CURB-65计分、器官衰竭发生率、ICU入住率、30 d死亡率4组间进行两两比较,差异有统计学意义( P<0.05);RDW预测老年CAP死亡的受试者工作曲线( ROC)的曲线下面积( AUC)=0.75。结论 RDW可作为临床对老年CAP患者病情严重程度的评估指标之一,对预测老年CAP患者死亡预后有一定意义。%Objective To investigate the predictive value of red cell distribution width ( RDW) in the aged patients with community acquired pneumonia(CAP). Methods 205 elderly patients with CAP from the Emergency Medical Ward and Emergency Intensive Care Unit of the First Affiliated Hospital of Anhui Medical University were retrospectively analyzed.According to RDW on admission, the patients with CAP were divided into four groups.CURB-65 scores, organ failure, intensive care unit occupancy, the duration of hospital stay and 30 -day mortality outcomes were detected and compared among the groups, and RDW was statistically analyzed to predict mortality in these patients. Results Among the four groups, CURB-65, incidence of organ failure, ICU occupancy rate and 30-day mortality were statistically different (P<0.05).ROC curve was drawn to evaluate the predictive role of RDW in elderly CAP death, the area under the curve ( AUC) =0.75.Conclusion RDW can be used as a clinical evaluation of the severity of disease in elderly patients with CAP of one of the indicators.It is of some

  19. Measurement of platelet aggregation, independently of patient platelet count

    DEFF Research Database (Denmark)

    Vinholt, P. J.; Frederiksen, H.; Hvas, A.M.

    2017-01-01

    platelet aggregation ruled out bleeding tendency in thrombocytopenic patients. Summary: 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...... platelets at platelet counts of > 10 × 109 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...

  20. Effects of platelet-poor plasma, platelet-rich plasma, and platelet-rich fibrin on healing of extraction sockets with buccal dehiscence in dogs.

    Science.gov (United States)

    Hatakeyama, Ichiro; Marukawa, Eriko; Takahashi, Yukinobu; Omura, Ken

    2014-02-01

    Alveolar bone resorption generally occurs during healing after tooth extraction. This study aimed to evaluate the effects of platelet-poor plasma (PPP), platelet-rich plasma (PRP), and platelet-rich fibrin (PRF) on healing in a ridge-augmentation model of the canine socket with dehiscence of the buccal wall. The third mandibular premolars of 12 beagle dogs were extracted and a 3 mm buccal dehiscence from the alveolar crest to the buccal wall of the extraction socket was created. These sockets were then divided into four groups on the basis of the material used to fill the sockets: PPP, PRP, PRF, and control (no graft material) groups. Results were evaluated at 4 and 8 weeks after surgery. The ultrastructural morphology and constructs of each blood product were studied by a scanning electron microscope (SEM) or calculating concentrations of platelets, fibrinogen, platelet-derived growth factor, and transforming growth factor-β. A total of five microcomputed tomography images of specimens were selected for measurement, and the area occupied by the newly formed bone as well as the horizontal bone width were measured. Moreover, decalcified tissue specimens from each defect were analyzed histologically. The median area of new bone at 4 and 8 weeks and median horizontal bone width at 8 weeks were the highest in the PPP group. However, bone maturation in the PRF and the PRP groups was more progressed than that in the PPP and control groups. By SEM findings, the PRF group showed a more highly condensed fibrin fiber network that was regularly arranged when compared with the PPP and PRP groups. The growth factors released from platelets in PRP indicated higher concentrations than that in PRF. Under more severe conditions for bone formation, as in this experiment, the growth factors released from platelets had a negative effect on bone formation. This study showed that PPP is an effective material for the preservation of sockets with buccal dehiscence.

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

    Directory of Open Access Journals (Sweden)

    Keith B Neeves

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

  2. Platelet-collagen adhesion enhances platelet aggregation induced by binding of VWF to platelets

    Energy Technology Data Exchange (ETDEWEB)

    Laduca, F.M.; Bell, W.R.; Bettigole, R.E. (Johns Hopkins Univ. School of Medicine, Baltimore, MD (USA) State Univ. of New York, Buffalo (USA))

    1987-11-01

    Ristocetin-induced platelet aggregation (RIPA) was evaluated in the presence of platelet-collagen adhesion. RIPA of normal donor platelet-rich plasma (PRP) demonstrated a primary wave of aggregation mediated by the binding of von Willebrand factor (VWF) to platelets and a secondary aggregation wave, due to a platelet-release reaction, initiated by VWF-platelet binding and inhibitable by acetylsalicylic acid (ASA). An enhanced RIPA was observed in PRP samples to which collagen had been previously added. These subthreshold concentrations of collagen, which by themselves were insufficient to induce aggregation, caused measurable platelet-collagen adhesion. Subthreshold collagen did not cause microplatelet aggregation, platelet release of ({sup 3}H)serotonin, or alter the dose-responsive binding of {sup 125}I-labeled VWF to platelets, which occurred with increasing ristocetin concentrations. However, ASA inhibition of the platelet release reaction prevented collagen-enhanced RIPA. These results demonstrate that platelet-collagen adhesion altered the platelet-release reaction induced by the binding of VWF to platelets causing a platelet-release reaction at a level of VWF-platelet binding not normally initiating a secondary aggregation. These findings suggest that platelet-collagen adhesion enhances platelet function mediated by VWF.

  3. Hybrid Exotic Meson Decay Width

    CERN Document Server

    Cook, M S

    2005-01-01

    We present results of a decay width calculation for a hybrid exotic meson(h, JPC=1-+) in the decay channel h to pi+a1. This calculation uses quenched lattice QCD and Luescher's finite box method. Operators for the h and pi+a1 states are used in a correlation matrix which was expanded by varying the smearing and fuzzing levels at source and sink points. Scattering phase shifts for a discrete set of relative pi+a1 momenta are determined using eigenvalues of the correlation matrix and formulae derived by Luescher. The phase shift data is very sparse, but fits to a Breit-Wigner model are made, resulting in a decay width of about 80 MeV.

  4. On the maximal diphoton width

    CERN Document Server

    Salvio, Alberto; Strumia, Alessandro; Urbano, Alfredo

    2016-01-01

    Motivated by the 750 GeV diphoton excess found at LHC, we compute the maximal width into $\\gamma\\gamma$ that a neutral scalar can acquire through a loop of charged fermions or scalars as function of the maximal scale at which the theory holds, taking into account vacuum (meta)stability bounds. We show how an extra gauge symmetry can qualitatively weaken such bounds, and explore collider probes and connections with Dark Matter.

  5. Probing eigenfunction nonorthogonality by parametric shifts of resonance widths

    CERN Document Server

    Savin, D V

    2013-01-01

    Recently, it has been shown that the change of resonance widths in an open system under a perturbation of its interior is a sensitive indicator of the nonorthogonality of resonance states. We apply this measure to quantify parametric motion of the resonances. In particular, a strong redistribution of the widths is linked with the maximal degree of nonorthogonality. Then for weakly open chaotic systems we discuss the role of spectral rigidity on the statistical properties of the parametric width shifts, and derive the distribution of the latter in a picket-fence model with equidistant spectrum.

  6. Changes and Clinical Significance of Platelet Parameters in Patients with Cirrhosis%肝硬化患者血小板参数变化及临床意义

    Institute of Scientific and Technical Information of China (English)

    许海霞; 王秀玲; 佟雪松

    2014-01-01

    目的:探讨肝硬化患者血小板参数的变化及临床价值。方法:用血液分析仪检测128例肝硬化患者(肝硬化组,其中出血组32例,无出血组96例)的血小板参数指标,与110例健康对照组的血小板参数比较。结果:肝硬化组与健康对照组比较,血小板计数(PLT)和血小板压积(PCT)低于健康对照组,平均血小板体积(MPV)、血小板分布宽度(PDW)和大血小板比率(P-LCR)高于健康对照组,差异有统计学意义(P<0.05)。出血组PLT和PCT低于无出血组,而出血组MPV、PDW和P-LCR均高于无出血组,差异有统计学意义(P<0.05)。结论:肝硬化患者的血小板存在质量和数量方面的异常,血小板参检测可以反映肝硬化患者肝细胞损伤程度,为临床对病情判断、治疗及预后提供有价值的参考依据。%Objective:To investigate the changes and clinical value of platelet parameters in patients with cirrhosis.Method:To detect parameter index with blood analyzer for 128 cases of cirrhosis platelet,and compare with 110 cases of platelet parameters in healthy control group.Result:The platelet count(PLT) and platelet hematocrit(PCT) in cirrhosis group were lower than the healthy control group,the mean platelet volume (MPV),platelet distribution width (PDW) and large platelet ratio(P-LCR) in cirrhosis group were higher than the healthy control group,the differences were statistically significance(P<0.05).The platelet count(PLT) and platelet hematocrit(PCT) in bleeding group were lower than non-bleeding group,the mean platelet volume(MPV),platelet distribution width(PDW) and large platelet ratio(P-LCR) in bleeding group were higher than the non-bleeding group,the differences were statistically significance(P<0.05). Conclusion:The platelets of cirrhosis patients have abnormal aspects of quality and quantity,detection of platelet parameters may reflect the degree of liver cell injury for patients with cirrhosis,for clinical

  7. Association of Red Cell Distribution Width and Serum Uric Acid in Preeclampsia%红细胞体积分布宽度及血清尿酸与先兆子痫的相关性探讨

    Institute of Scientific and Technical Information of China (English)

    郭进京; 李黎

    2013-01-01

    Objective Purpose of this study was to evaluate the relation red blood cell distribution width (RDW) and serum u-ric acid in preeclampsia.Methods A case-control study was conducted on singleton preeclamptic pregnancies deliverd between 37 and 40 weeks, gestation at Weinan Municipal Maternal and Child Health Hospital from October 2010 to December 2012 and control groups constituted 97 singleton pregnant normotensive.RDW, hemoglobin and serum uric acid concentration were determind.Results ①RDW and serum uric acid concentration were higher in preeclampsia compared with the controls (t=2.55,P=0.029 ; t= 1.425, P=0.031 respectively).②preeclampsia patients were divided into 2 groups according to RDW at baseling (14.7%) a high RDW(≥14.7%) and a low RDW (<14.7%).The uterine-incision delivery rates and placental abruption rates and low weigh fetus rates in preeclampsia patients with high RDW were more significantly statistical different with that of the a low RDW preeclampsia patients (χ2=7.58, P=0.006 ;χ2= 6.64, P=0.011;χ2 =6.84, P = 0.009 respectively).The serum uric acid concentration were not significantly different with that of controls (t=4.17, P= 0.058).②Multivarate analysis identified higher RDW were strongly risk factor in preeclampsia (OR=1.81, P=0.017).Conclusion Higher RDW lever are strongly correlated with preeclampsia patients.%目的 评价红细胞体积分布宽度(RDW)及血清尿酸与先兆子痫发病的关系.方法 采用病例-对照的研究方法,选取2010年10月~2012年12月在渭南市妇幼保健院住院,妊娠37~40周109例单胎先兆子痫患者;同时选取同孕周正常血压单胎孕妇97例为对照组,分别检测其RDW,Hb及血清尿酸等指标.结果 ①先兆子痫患者RDW及血清尿酸明显高于对照组(t=2.55,P=0.029;t=1.425,P=0.031).②以RDW基线水平14.7%为标准,高RDW(≥14.7%)先兆子痫组剖宫产率、胎盘早剥率及低体重胎儿率与低RDW(<14.7%)比较差异具有显著统

  8. Resonance trapping and saturation of decay widths

    CERN Document Server

    Persson, E; Rotter, I

    1998-01-01

    Resonance trapping appears in open many-particle quantum systems at high level density when the coupling to the continuum of decay channels reaches a critical strength. Here a reorganization of the system takes place and a separation of different time scales appears. We investigate it under the influence of additional weakly coupled channels as well as by taking into account the real part of the coupling term between system and continuum. We observe a saturation of the mean width of the trapped states. Also the decay rates saturate as a function of the coupling strength. The mechanism of the saturation is studied in detail. In any case, the critical region of reorganization is enlarged. When the transmission coefficients for the different channels are different, the width distribution is broadened as compared to a chi_K^2 distribution where K is the number of channels. Resonance trapping takes place before the broad state overlaps regions beyond the extension of the spectrum of the closed system.

  9. Defining Platelet Function During Polytrauma

    Science.gov (United States)

    2013-02-01

    using calibrated automated thrombography ( CAT ). 3. Platelet-induced clot contraction and using viscoelastic measures such as TEG with Platelet Mapping...using calibrated automated thrombography ( CAT ) in platelet-rich plasma. 3. Platelet-induced clot contraction and effect on clot structure by platelet...if injury with stable vital signs on initial evaluation.  Pregnancy (confirmed with urine pregnancy testing)  Documented do not resuscitate order

  10. 红细胞分布宽度对老年急性肺栓塞患者近期预后的影响分析%Effect of red cell distribution width on early prognosis of elderly acute pulmonary embolism patients

    Institute of Scientific and Technical Information of China (English)

    郭倩玉; 卢成志; 夏大胜; 赵向东; 陈欣

    2013-01-01

    目的 探讨红细胞分布宽度(RDW)对老年急性肺栓塞患者近期预后的影响.方法 回顾性分析我院81例老年急性肺栓塞患者临床资料,根据RDW水平分为3组,RDW低值组27例,RDW中值组27例,RDW高值组27例,比较3组患者住院死亡、休克发生率及其他血流动力学、实验室指标.结果 随RDW水平升高,RDW低值组、RDW中值组和RDW高值组住院病死率、死亡和休克总发生率、N末端B型利钠肽前体水平明显增加(P<0.05).Pearson相关分析显示,与死亡发生的相关因素是年龄、收缩压、心率、N末端B型利钠肽前体、肌钙蛋白I、RDW(P<0.05,P<0.01).logistic多因素回归分析显示,年龄、收缩压、心率是住院死亡的独立影响因素(P<0.05,P<0.01).结论 老年急性肺栓塞患者RDW升高者住院死亡和休克的发生率增加.%Objective To study the effect of red cell distribution width on early prognosis of elderly acute pulmonary embolism patients .Methods Clinical data about 81 elderly acute pulmonary embolism patients were retrospectively analyzed .The patients were divided into low red cell distribution width group ,medium red cell distribution width group ,and high red cell distribution width group(27 in each group) .The in-hospital incidence of death ,hemodynamics change and labotatory findings were compared among the 3 groups .Results The total in-hospital incidence of death , plasma N-terminal probrain natriutetic peptide (NT-proBNP) level increased with the elevated red cell distribution width in low ,medium and high red cell distribution width groups (P<0.05). Pearson correlation analysis showed that age ,systolic blood pressure ,heart rate ,NT-proBNP ,tro-ponin I and red cell distribution width were the relative factors for in-hospital death ( P<0 .05 , P<0 .01) .Multivariate logistic regression analysis showed that age , systolic blood pressure and heart rate were the independent factors for in-hospital death ( P<0. 05 , P<0 .01

  11. Thrombin Increases Expression of Fibronectin Antigen on the Platelet Surface

    Science.gov (United States)

    Ginsberg, Mark H.; Painter, Richard G.; Forsyth, Jane; Birdwell, Charles; Plow, Edward F.

    1980-02-01

    Fibronectins (fn) are adhesive glycoproteins which bind to collagen and to fibrin and appear to be important in cellular adhesion to other cells or surfaces. Fn-related antigen is present in human platelets, suggesting a possible role for fn in the adhesive properties of platelets. We have studied the localization of fn in resting and thrombin-stimulated platelets by immunofluorescence and quantitative binding of radiolabeled antibody. In resting fixed platelets, variable light surface staining for fn was observed. When these cells were made permeable to antibody with detergent, staining for fn was markedly enhanced and was present in a punctate distribution, suggesting intracellular localization. Stimulation with thrombin, which is associated with increased platelet adhesiveness, resulted in increased staining for fn antigen on intact platelets. These stimulated cells did not leak 51Cr nor did they stain for F-actin, thus documenting that the increased fn staining was not due to loss of plasma membrane integrity. The thrombin-induced increase in accessible platelet fn antigen was confirmed by quantitative antibody binding studies in which thrombin-stimulated platelets specifically bound 15 times as much radiolabeled F(ab')2 anti-fn as did resting cells. Thus, thrombin stimulation results in increased expression of fn antigen on the platelet surface. Here it may participate in interactions with fibrin, connective tissue, or other cells.

  12. Masses, widths, and leptonic widths of the higher upsilon resonances

    Energy Technology Data Exchange (ETDEWEB)

    Lovelock, D.M.J.; Horstkotte, J.E.; Klopfenstein, C.; Lee-Franzini, J.; Romero, L.; Schamberger, R.D.; Youssef, S.; Franzini, P.; Son, D.; Tuts, P.M.

    1985-02-04

    The masses, total widths, and leptonic widths of three triplet s-wave bb-bar states UPSILON(4S), UPSILON(5S), and UPSILON(6S) are determined from measurements of the e/sup +/e/sup -/ annihilation cross section into hadrons for 10.55

  13. Spreading widths of doorway states

    Energy Technology Data Exchange (ETDEWEB)

    De Pace, A., E-mail: depace@to.infn.i [Istituto Nazionale di Fisica Nucleare, Sezione di Torino, via P. Giuria 1, I-10125 Torino (Italy); Molinari, A. [Dipartimento di Fisica Teorica dell' Universita di Torino, via P. Giuria 1, I-10125 Torino (Italy); Istituto Nazionale di Fisica Nucleare, Sezione di Torino, via P. Giuria 1, I-10125 Torino (Italy); Weidenmueller, H.A. [Max-Planck-Institut fuer Kernphysik, D-69029 Heidelberg (Germany)

    2011-01-01

    As a function of energy E, the average doorway strength function S(E)-bar of a doorway state is commonly assumed to be Lorentzian in shape and characterized by two parameters, the peak energy E{sub 0} and the spreading width {Gamma}{sup {down_arrow}}. The simple picture is modified when the density of background states that couple to the doorway state changes significantly in an energy interval of size {Gamma}{sup {down_arrow}}. For that case we derive an approximate analytical expression for S(E)-bar. We test our result successfully against numerical simulations. Our result may have important implications for shell-model calculations.

  14. N-Widths and Average Widths of Besov Classes in Sobolev Spaces

    Institute of Scientific and Technical Information of China (English)

    Gui Qiao XU; Yong Sheng SUN; Yong Ping LIU

    2006-01-01

    In this paper, we consider the n-widths and average widths of Besov classes in the usual Sobolev spaces. The weak asymptotic results concerning the Kolmogorov n-widths, the linear n-widths,the Gel'fand n-widths, in the Sobolev spaces on Td, and the infinite-dimensional widths and the average widths in the Sobolev spaces on Rd are obtained, respectively.

  15. Clinical application of radiolabelled platelets

    Energy Technology Data Exchange (ETDEWEB)

    Kessler, C. (Medical University Luebeck (Federal Republic of Germany). Department of Neurology); Hardeman, M.R. (Amsterdam Univ. (Netherlands). Academisch Ziekenhuis); Henningsen, H. (Heidelberg Univ. (Germany, F.R.). Neurologische Klinik); Petrovici, J.-N. (Cologne-Merheim Hospital (Federal Republic of Germany). Department of Neurology) (eds.)

    1990-01-01

    The increasing number of therapeutic modalities available for the management of patients with thromboembolic complications, such as fibrinolytic treatment or vascular surgery, require the development of new imaging techniques to provide more information on the xtent, age and activity of the thromboembolic material causing clinical symptoms. Since the introduction of radiolabelling of platelets with indium-111, platelet scintigraphy (PSC) has been used as a tool in the diagnosis of various thromboembolic diseases. During the International Symposium on Radiolabelled Platelets scientists from a variety of medical backgrounds presented their results on the clinical applictions of radiolabelled platelets. The papers presented there have been updated to take account of the latest results before publication in this volume. 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. refs.; figs.; tabs.

  16. Platelet preservation: agitation and containers.

    Science.gov (United States)

    van der Meer, Pieter F; de Korte, Dirk

    2011-06-01

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

  17. 红细胞分布宽度与冠心病相关性的性别差异探讨%Gender differences in relationship between red cell distribution width and coronary artery disease

    Institute of Scientific and Technical Information of China (English)

    马凤莲; 名盛; 刘俊; 李小林; 郭远林; 朱成刚; 徐瑞霞; 刘庚; 董倩

    2013-01-01

    目的 冠心病的临床特征具有明显的性别差异,既往研究证实红细胞分布宽度(RDW)与冠心病发生与发展有一定关系.本文探讨RDW与冠心病相关性的性别差异.方法 连续收集因胸痛疑诊冠心病的患者674例,根据冠状动脉造影(CAG)结果分为冠心病组499例(男性352例,女性147例)与对照组175例(男性89例,女性86例).分析冠心病传统危险因素在不同性别的差异,探讨RDW在不同性别冠心病患者中的分布情况.结果 不同性别总体的基线资料比较中,年龄、吸烟史、家族史、血红蛋白水平有性别差异(P<0.05),男女两组的RDW无明显差异(P>0.05).不同性别的冠心病组与对照组相比,女性冠心病组与女性对照组相比,RDW显著升高[(12.9±0.7)% vs (12.6±0.6)%,P=0.001],男性冠心病组与男性对照组相比,RDW无统计学差异[(13.0±0.8)%vs (12.8±1.0)%,P=0.144].女性冠心病患者多因素logistic回归分析显示,年龄和RDW是女性冠心病患者的独立预测因素(OR=1.07,95%CI:1.03~1.10,P<0.001 ; OR=2.03,95%CI:1.28~3.23,P<0.01).女性RDW的ROC曲线下面积(AUC)=0.63,95%CI:0.56~0.70,RDW界值为12.75%,敏感性为57.1%,特异性为66.3%.结论 RDW与冠心病之相关性存在性别差异,是女性冠心病的独立预测因素之一.%Objective To explore the gender differences in red cell distribution width (RDW) and CAD. Methods A total of 674 consecutively admitted patients from May 2011 to May 2012 in Fu Wai Hospital were analyzed. All patients had received coronary angiography (CAG) and then were divided into two groups based on the results of CAG: CAD group consisting of 499 patients (male=352, female=147), and control group consisting of 175 subjects (male=89, female=86). The clinical characteristics including traditional CAD risk factors were collected, and their gender differences and the gender differences in RDW and CAD were analysed. Results There were significant

  18. Investigating Starburst Galaxy Emission Line Equivalent Widths

    Science.gov (United States)

    Meskhidze, Helen; Richardson, Chris T.

    2016-01-01

    Modeling star forming galaxies with spectral synthesis codes allows us to study the gas conditions and excitation mechanisms that are necessary to reproduce high ionization emission lines in both local and high-z galaxies. Our study uses the locally optimally-emitting clouds model to develop an atlas of starburst galaxy emission line equivalent widths. Specifically, we address the following question: What physical conditions are necessary to produce strong high ionization emission lines assuming photoionization via starlight? Here we present the results of our photoionization simulations: an atlas spanning 15 orders of magnitude in ionizing flux and 10 orders of magnitude in hydrogen density that tracks over 150 emission lines ranging from the UV to the near IR. Each simulation grid contains ~1.5x104 photoionization models calculated by supplying a spectral energy distribution, grain content, and chemical abundances. Specifically, we will be discussing the effects on the emission line equivalent widths of varying the metallicity of the cloud, Z = 0.2 Z⊙ to Z = 5.0 Z⊙, and varying the star-formation history, using the instantaneous and continuous evolution tracks and the newly released Starburst99 Geneva rotation tracks.

  19. Platelets and cardiac arrhythmia

    Directory of Open Access Journals (Sweden)

    Jonas S De Jong

    2010-12-01

    Full Text Available Sudden cardiac death remains one of the most prevalent modes of death in industrialized countries, and myocardial ischemia due to thrombotic coronary occlusion is its primary cause. The role of platelets in the occurrence of SCD extends beyond coronary flow impairment by clot formation. Here we review the substances released by platelets during clot formation and their arrhythmic properties. Platelet products are released from three types of platelet granules: dense core granules, alpha-granules, and platelet lysosomes. The physiologic properties of dense granule products are of special interest as a potential source of arrhythmic substances. They are released readily upon activation and contain high concentrations of serotonin, histamine, purines, pyrimidines, and ions such as calcium and magnesium. Potential arrhythmic mechanisms of these substances, e.g. serotonin and high energy phosphates, include induction of coronary constriction, calcium overloading, and induction of delayed after-depolarizations. Alpha-granules produce thromboxanes and other arachidonic acid products with many potential arrhythmic effects mediated by interference with cardiac sodium, calcium and potassium channels. Alpha-granules also contain hundreds of proteins that could potentially serve as ligands to receptors on cardiomyocytes. Lysosomal products probably do not have an important arrhythmic effect. Platelet products and ischemia can induce coronary permeability, thereby enhancing interaction with surrounding cardiomyocytes. Antiplatelet therapy is known to improve survival after myocardial infarction. Although an important part of this effect results from prevention of coronary clot formation, there is evidence to suggest that antiplatelet therapy also induces anti-arrhythmic effects during ischemia by preventing the release of platelet activation products.

  20. Direct measurement of the W boson width

    Energy Technology Data Exchange (ETDEWEB)

    Abazov, V.M.; /Dubna, JINR; Abbott, B.; /Oklahoma U.; Abolins, M.; /Michigan State U.; Acharya, B.S.; /Tata Inst.; Adams, M.; /Illinois U., Chicago; Adams, T.; /Florida State U.; Aguilo, E.; /Alberta U. /Simon Fraser U. /McGill U.; Ahsan, M.; /Kansas State U.; Alexeev, G.D.; /Dubna, JINR; Alkhazov, G.; /St. Petersburg, INP; Alton, A.; /Michigan U. /Northeastern U.

    2009-09-01

    We present a direct measurement of the width of the W boson using the shape of the transverse mass distribution of W {yields} e{nu} candidates selected in 1 fb{sup -1} of data collected with the D0 detector at the Fermilab Tevatron collider in p{bar p} collisions at {radical}s = 1.96 TeV. We use the same methods and data sample that were used for our recently published W boson mass measurement, except for the modeling of the recoil, which is done with a new method based on a recoil library. Our result, 2.028 {+-} 0.072 GeV, is in agreement with the predictions of the standard model and is the most precise direct measurement result from a single experiment to date.

  1. Direct measurement of the W boson width.

    Science.gov (United States)

    Abazov, V M; Abbott, B; Abolins, M; Acharya, B S; Adams, M; Adams, T; Aguilo, E; Ahsan, M; Alexeev, G D; Alkhazov, G; Alton, A; Alverson, G; Alves, G A; Ancu, L S; Andeen, T; Anzelc, M S; Aoki, M; Arnoud, Y; Arov, M; Arthaud, M; Askew, A; Asman, B; Atramentov, O; Avila, C; BackusMayes, J; Badaud, F; Bagby, L; Baldin, B; Bandurin, D V; Banerjee, S; Barberis, E; Barfuss, A-F; Bargassa, P; Baringer, P; Barreto, J; Bartlett, J F; Bassler, U; Bauer, D; Beale, S; Bean, A; Begalli, M; Begel, M; Belanger-Champagne, C; Bellantoni, L; Benitez, J A; Beri, S B; Bernardi, G; Bernhard, R; Bertram, I; Besançon, M; Beuselinck, R; Bezzubov, V A; Bhat, P C; Bhatnagar, V; Blazey, G; Blessing, S; Bloom, K; Boehnlein, A; Boline, D; Bolton, T A; Boos, E E; Borissov, G; Bose, T; Brandt, A; Brock, R; Brooijmans, G; Bross, A; Brown, D; Bu, X B; Buchholz, D; Buehler, M; Buescher, V; Bunichev, V; Burdin, S; Burnett, T H; Buszello, C P; Calfayan, P; Calpas, B; Calvet, S; Cammin, J; Carrasco-Lizarraga, M A; Carrera, E; Carvalho, W; Casey, B C K; Castilla-Valdez, H; Chakrabarti, S; Chakraborty, D; Chan, K M; Chandra, A; Cheu, E; Cho, D K; Cho, S W; Choi, S; Choudhary, B; Christoudias, T; Cihangir, S; Claes, D; Clutter, J; Cooke, M; Cooper, W E; Corcoran, M; Couderc, F; Cousinou, M-C; Cutts, D; Cwiok, M; Das, A; Davies, G; De, K; de Jong, S J; De La Cruz-Burelo, E; DeVaughan, K; Déliot, F; Demarteau, M; Demina, R; Denisov, D; Denisov, S P; Desai, S; Diehl, H T; Diesburg, M; Dominguez, A; Dorland, T; Dubey, A; Dudko, L V; Duflot, L; Duggan, D; Duperrin, A; Dutt, S; Dyshkant, A; Eads, M; Edmunds, D; Ellison, J; Elvira, V D; Enari, Y; Eno, S; Escalier, M; Evans, H; Evdokimov, A; Evdokimov, V N; Facini, G; Ferapontov, A V; Ferbel, T; Fiedler, F; Filthaut, F; Fisher, W; Fisk, H E; Fortner, M; Fox, H; Fuess, S; Gadfort, T; Galea, C F; Garcia-Bellido, A; Gavrilov, V; Gay, P; Geist, W; Geng, W; Gerber, C E; Gershtein, Y; Gillberg, D; Ginther, G; Golovanov, G; Gómez, B; Goussiou, A; Grannis, P D; Greder, S; Greenlee, H; Greenwood, Z D; Gregores, E M; Grenier, G; Gris, Ph; Grivaz, J-F; Grohsjean, A; Grünendahl, S; Grünewald, M W; Guo, F; Guo, J; Gutierrez, G; Gutierrez, P; Haas, A; Haefner, P; Hagopian, S; Haley, J; Hall, I; Hall, R E; Han, L; Harder, K; Harel, A; Hauptman, J M; Hays, J; Hebbeker, T; Hedin, D; Hegeman, J G; Heinson, A P; Heintz, U; Hensel, C; Heredia-De La Cruz, I; Herner, K; Hesketh, G; Hildreth, M D; Hirosky, R; Hoang, T; Hobbs, J D; Hoeneisen, B; Hohlfeld, M; Hossain, S; Houben, P; Hu, Y; Hubacek, Z; Huske, N; Hynek, V; Iashvili, I; Illingworth, R; Ito, A S; Jabeen, S; Jaffré, M; Jain, S; Jakobs, K; Jamin, D; Jesik, R; Johns, K; Johnson, C; Johnson, M; Johnston, D; Jonckheere, A; Jonsson, P; Juste, A; Kajfasz, E; Karmanov, D; Kasper, P A; Katsanos, I; Kaushik, V; Kehoe, R; Kermiche, S; Khalatyan, N; Khanov, A; Kharchilava, A; Kharzheev, Y N; Khatidze, D; Kirby, M H; Kirsch, M; Klima, B; Kohli, J M; Konrath, J-P; Kozelov, A V; Kraus, J; Kuhl, T; Kumar, A; Kupco, A; Kurca, T; Kuzmin, V A; Kvita, J; Lacroix, F; Lam, D; Lammers, S; Landsberg, G; Lebrun, P; Lee, H S; Lee, W M; Leflat, A; Lellouch, J; Li, L; Li, Q Z; Lietti, S M; Lim, J K; Lincoln, D; Linnemann, J; Lipaev, V V; Lipton, R; Liu, Y; Liu, Z; Lobodenko, A; Lokajicek, M; Love, P; Lubatti, H J; Luna-Garcia, R; Lyon, A L; Maciel, A K A; Mackin, D; Mättig, P; Magaña-Villalba, R; Mal, P K; Malik, S; Malyshev, V L; Maravin, Y; Martin, B; McCarthy, R; McGivern, C L; Meijer, M M; Melnitchouk, A; Mendoza, L; Menezes, D; Mercadante, P G; Merkin, M; Meyer, A; Meyer, J; Mondal, N K; Montgomery, H E; Moore, R W; Moulik, T; Muanza, G S; Mulhearn, M; Mundal, O; Mundim, L; Nagy, E; Naimuddin, M; Narain, M; Neal, H A; Negret, J P; Neustroev, P; Nilsen, H; Nogima, H; Novaes, S F; Nunnemann, T; Obrant, G; Ochando, C; Onoprienko, D; Orduna, J; Oshima, N; Osman, N; Osta, J; Otec, R; Otero y Garzón, G J; Owen, M; Padilla, M; Padley, P; Pangilinan, M; Parashar, N; Park, S-J; Park, S K; Parsons, J; Partridge, R; Parua, N; Patwa, A; Penning, B; Perfilov, M; Peters, K; Peters, Y; Pétroff, P; Piegaia, R; Piper, J; Pleier, M-A; Podesta-Lerma, P L M; Podstavkov, V M; Pogorelov, Y; Pol, M-E; Polozov, P; Popov, A V; Prewitt, M; Protopopescu, S; Qian, J; Quadt, A; Quinn, B; Rakitine, A; Rangel, M S; Ranjan, K; Ratoff, P N; Renkel, P; Rich, P; Rijssenbeek, M; Ripp-Baudot, I; Rizatdinova, F; Robinson, S; Rominsky, M; Royon, C; Rubinov, P; Ruchti, R; Safronov, G; Sajot, G; Sánchez-Hernández, A; Sanders, M P; Sanghi, B; Savage, G; Sawyer, L; Scanlon, T; Schaile, D; Schamberger, R D; Scheglov, Y; Schellman, H; Schliephake, T; Schlobohm, S; Schwanenberger, C; Schwienhorst, R; Sekaric, J; Severini, H; Shabalina, E; Shamim, M; Shary, V; Shchukin, A A; Shivpuri, R K; Siccardi, V; Simak, V; Sirotenko, V; Skubic, P; Slattery, P; Smirnov, D; Snow, G R; Snow, J; Snyder, S; Söldner-Rembold, S; Sonnenschein, L; Sopczak, A; Sosebee, M; Soustruznik, K; Spurlock, B; Stark, J; Stolin, V; Stoyanova, D A; Strandberg, J; Strang, M A; Strauss, E; Strauss, M; Ströhmer, R; Strom, D; Stutte, L; Sumowidagdo, S; Svoisky, P; Takahashi, M; Tanasijczuk, A; Taylor, W; Tiller, B; Titov, M; Tokmenin, V V; Torchiani, I; Tsybychev, D; Tuchming, B; Tully, C; Tuts, P M; Unalan, R; Uvarov, L; Uvarov, S; Uzunyan, S; van den Berg, P J; Van Kooten, R; van Leeuwen, W M; Varelas, N; Varnes, E W; Vasilyev, I A; Verdier, P; Vertogradov, L S; Verzocchi, M; Vesterinen, M; Vilanova, D; Vint, P; Vokac, P; Wagner, R; Wahl, H D; Wang, M H L S; Warchol, J; Watts, G; Wayne, M; Weber, G; Weber, M; Wenger, A; Wetstein, M; White, A; Wicke, D; Williams, M R J; Wilson, G W; Wimpenny, S J; Wobisch, M; Wood, D R; Wyatt, T R; Xie, Y; Xu, C; Yacoob, S; Yamada, R; Yang, W-C; Yasuda, T; Yatsunenko, Y A; Ye, Z; Yin, H; Yip, K; Yoo, H D; Youn, S W; Yu, J; Zeitnitz, C; Zelitch, S; Zhao, T; Zhou, B; Zhu, J; Zielinski, M; Zieminska, D; Zivkovic, L; Zutshi, V; Zverev, E G

    2009-12-04

    We present a direct measurement of the width of the W boson using the shape of the transverse mass distribution of W --> enu candidate events. Data from approximately 1 fb(-1) of integrated luminosity recorded at square root of s = 1.96 TeV by the D0 detector at the Fermilab Tevatron pp collider are analyzed. We use the same methods and data sample that were used for our recently published W boson mass measurement, except for the modeling of the recoil, which is done with a new method based on a recoil library. Our result, 2.028 +/- 0.072 GeV, is in agreement with the predictions of the standard model.

  2. The Platelet and Platelet Function Testing in Liver Disease

    NARCIS (Netherlands)

    Hugenholtz, Greg G. C.; Porte, Robert J.; Lisman, Ton

    2009-01-01

    Patients who have liver disease commonly present with alterations in platelet number and function. Recent data have questioned the contribution of these changes to bleeding complications in these patients. Modern tests of platelet function revealed compensatory mechanisms for the decreased platelet

  3. Investigation of platelet function and platelet disorders using flow cytometry.

    Science.gov (United States)

    Rubak, Peter; Nissen, Peter H; Kristensen, Steen D; Hvas, Anne-Mette

    2016-01-01

    Patients with thrombocytopenia or platelet disorders are at risk of severe bleeding. We report the development and validation of flow cytometry assays to diagnose platelet disorders and to assess platelet function independently of platelet count. The assays were developed to measure glycoprotein levels (panel 1) and platelet function (panel 2) in sodium citrated blood. Twenty healthy volunteers and five patients diagnosed with different platelet disorders were included. Glycoprotein expression levels of the receptors Ia, Ib, IIb, IIIa and IX were measured and normalised with forward scatter (FS) as a measurement of platelet size. Platelet function was assessed by CD63, P-selectin and bound fibrinogen in response to arachidonic acid, adenosine diphosphate (ADP), collagen-related peptide, ristocetin and thrombin receptor-activation peptide-6. All patients except one with suspected δ-granule defect showed aberrant levels of glycoproteins in panel 1. Glanzmann's thrombasthenia and genetically verified Bernard-Soulier syndrome could be diagnosed using panel 1. All patients showed reduced platelet function according to at least one agonist. Using panel 2 it was possible to diagnose Bernard-Soulier syndrome, δ-granule defect and GPVI disorder. By combining the two assays, we were able to diagnose different platelet disorders and investigate platelet function independent of platelet count.

  4. Reproducibility of Manual Platelet Estimation Following Automated Low Platelet Counts

    Directory of Open Access Journals (Sweden)

    Zainab S Al-Hosni

    2016-11-01

    Full Text Available Objectives: Manual platelet estimation is one of the methods used when automated platelet estimates are very low. However, the reproducibility of manual platelet estimation has not been adequately studied. We sought to assess the reproducibility of manual platelet estimation following automated low platelet counts and to evaluate the impact of the level of experience of the person counting on the reproducibility of manual platelet estimates. Methods: In this cross-sectional study, peripheral blood films of patients with platelet counts less than 100 × 109/L were retrieved and given to four raters to perform manual platelet estimation independently using a predefined method (average of platelet counts in 10 fields using 100× objective multiplied by 20. Data were analyzed using intraclass correlation coefficient (ICC as a method of reproducibility assessment. Results: The ICC across the four raters was 0.840, indicating excellent agreement. The median difference of the two most experienced raters was 0 (range: -64 to 78. The level of platelet estimate by the least-experienced rater predicted the disagreement (p = 0.037. When assessing the difference between pairs of raters, there was no significant difference in the ICC (p = 0.420. Conclusions: The agreement between different raters using manual platelet estimation was excellent. Further confirmation is necessary, with a prospective study using a gold standard method of platelet counts.

  5. 14 CFR 121.115 - Route width.

    Science.gov (United States)

    2010-01-01

    ... Route width. (a) Routes and route segments over Federal airways, foreign airways, or advisory routes have a width equal to the designated width of those airways or advisory routes. Whenever the... clearance. (2) Minimum en route altitudes. (3) Ground and airborne navigation aids. (4) Air traffic density...

  6. Clique-width of unit interval graphs

    OpenAIRE

    Lozin, Vadim V.

    2007-01-01

    The clique-width is known to be unbounded in the class of unit interval graphs. In this paper, we show that this is a minimal hereditary class of unbounded clique-width, i.e., in every hereditary subclass of unit interval graphs the clique-width is bounded by a constant.

  7. Application of red blood cell distribution width in the early diagnosis of patients with chronic heart failure%红细胞分布宽度检验在慢性心力衰竭患者早期诊断中的应用研究

    Institute of Scientific and Technical Information of China (English)

    王社盈; 唐爱国; 杨俊

    2014-01-01

    Objective To investigate the clinical significance of red blood cell distribution width in the early diagnosis of patients with chronic heart failure.Methods Seventy eight cases of chronic heart failure patients from November 2011 to November 2013 in our hospital were recruited in this study,and were divided into three different heart failure groups (Ⅱ,Ⅲ,and Ⅳ) according to the degree of heart failure; 40 healthy cases were used as control group.The red blood cell distribution width was measured among four groups.The relationship of the red blood cell distribution width and chronic heart failure was analyzed.According to the red blood cell distribution width data,patients were grouped into < 13.1%,13.1% ~ 14.5%,and > 14.5% groups.The eventual fatality rates were compared among three groups with different red blood cell distribution width.Results (1) The red blood cell distribution width was (11.63 ±0.71)%,(13.11 ±1.08)%,(14.31 ±1.52)%,and (16.83 ±0.71)% in the healthy group,andⅡ,Ⅲ,and Ⅳ heart failure groups,respectively.The red blood cell distribution width was gradually increased with the degree of heart failure,with a statistically significant difference among four groups (P < 0.05).(2) The mortality was 0 (0/32),14.8% (4/29),and 41.2% (7/ 17) in different red blood cell distribution width groups (< 13.1%,13.1% ~ 14.5%,and > 14.5%),respectively.The mortality was gradually increased with the increased red blood cell distribution width,with a statistically significant difference among three groups (P < 0.05).Conclusions Red blood cell distribution width is of great importance to detect disease degree of chronic heart failure and can guide one to effectively evaluate disease processes and therapeutic effect.%目的 研究红细胞分布宽度检验在慢性心力衰竭患者早期诊断中的意义.方法 以本院2011年11月至2013年11月间收治的78例慢性心力衰竭患者为研究对象,首先按

  8. Modelling the widths of fission observables in GEF

    Directory of Open Access Journals (Sweden)

    Schmidt K.-H.

    2013-03-01

    Full Text Available The widths of the mass distributions of the different fission channels are traced back to the probability distributions of the corresponding quantum oscillators that are coupled to the heat bath, which is formed by the intrinsic degrees of freedom of the fissioning system under the influence of pairing correlations and shell effects. Following conclusion from stochastic calculations of Adeev and Pashkevich, an early freezing due to dynamical effects is assumed. It is shown that the mass width of the fission channels in low-energy fission is strongly influenced by the zero-point motion of the corresponding quantum oscillator. The observed variation of the mass widths of the asymmetric fission channels with excitation energy is attributed to the energy-dependent properties of the heat bath and not to the population of excited states of the corresponding quantum oscillator.

  9. Palindromic widths of nilpotent and wreath products

    Indian Academy of Sciences (India)

    Valeriy G Bardakov; Oleg V Bryukhanov; Krishnendu Gongopadhyay

    2017-02-01

    We prove that the nilpotent product of a set of groups $A_1, \\ldots , A_s$ has finite palindromic width if and only if the palindromic widths of $A_i$, $i = 1, \\ldots , s$, are finite. We give a new proof that the commutator width of $F_n \\wr K$ is infinite, where $F_n$ is a free group of rank $n\\geq 2$ and $K$ is a finite group. This result, combining with a result of Fink [9] gives examples of groups with infinite commutator width but finite palindromic width with respect to some generating set.

  10. Mean platelet volume and mean platelet volume/platelet count ratio ...

    African Journals Online (AJOL)

    Amira M. Elsayed

    2016-03-30

    Mar 30, 2016 ... Abstract The mean platelet volume (MPV) is a laboratory marker associated with platelet func- tion and activity. .... the first 24 h of presentation to the emergency department. Severity of ..... J Neurol Neurosurg Psychiatry.

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

    Science.gov (United States)

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

    2016-01-01

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

  12. Prophylactic platelets in dengue

    DEFF Research Database (Denmark)

    Whitehorn, James; Rodriguez Roche, Rosmari; Guzman, Maria G

    2012-01-01

    of platelets in dengue. Respondents were all physicians involved with the treatment of patients with dengue. Respondents were asked that their answers reflected what they would do if they were the treating physician. We received responses from 306 physicians from 20 different countries. The heterogeneity...

  13. Rho GTPases in platelet function.

    Science.gov (United States)

    Aslan, J E; McCarty, O J T

    2013-01-01

    The Rho family of GTP binding proteins, also commonly referred to as the Rho GTPases, are master regulators of the platelet cytoskeleton and platelet function. These low-molecular-weight or 'small' GTPases act as signaling switches in the spatial and temporal transduction, and amplification of signals from platelet cell surface receptors to the intracellular signaling pathways that drive platelet function. The Rho GTPase family members RhoA, Cdc42 and Rac1 have emerged as key regulators in the dynamics of the actin cytoskeleton in platelets and play key roles in platelet aggregation, secretion, spreading and thrombus formation. Rho GTPase regulators, including GEFs and GAPs and downstream effectors, such as the WASPs, formins and PAKs, may also regulate platelet activation and function. In this review, we provide an overview of Rho GTPase signaling in platelet physiology. Previous studies of Rho GTPases and platelets have had a shared history, as platelets have served as an ideal, non-transformed cellular model to characterize Rho function. Likewise, recent studies of the cell biology of Rho GTPase family members have helped to build an understanding of the molecular regulation of platelet function and will continue to do so through the further characterization of Rho GTPases as well as Rho GAPs, GEFs, RhoGDIs and Rho effectors in actin reorganization and other Rho-driven cellular processes. © 2012 International Society on Thrombosis and Haemostasis.

  14. Platelet reactive alloantibodies responsible for immune thrombocytopenia in Malay population

    Directory of Open Access Journals (Sweden)

    Mohd I. Armawai

    2014-10-01

    Full Text Available Background: Alloantibodies against human platelet alloantigens (HPAs are responsible for the development of platelet transfusion refractoriness (PTR in patients receiving random platelets and bleeding disorder in babies with fetal neonatal alloimmune thrombocytopenia (FNAIT. Recently, our results based on the analysis of the allelic distribution of HPAs indicated that immunization may occur among Malay. In this study, we sought to analyze the frequencies of platelet reactive alloantibodies responsible for FNAIT and PTR in Malaysia.Methods: Sera from suspected FNAIT (n = 295 and PTR (n = 74 were collected in five years period (2008-2013 and tested for the presence of platelet reactive antibodies by the use of antigen capture assay.Results: In 5/74 (5.41% platelet specific antibodies against HPA-2b (n = 1, HPA-5a (n = 1, HPA-5b (n = 1, HPA-15b (n = 2 could be identified in our PTR cohort. In FNAIT cohort, platelet specific alloantibodies could be detected in 18 sera (6.10% consisting anti-HPA-1a (n = 1, anti-HPA-3a (n = 3, anti-HPA-5a (n = 6, anti-HPA-5b (n = 6, anti-HPA-15a (n = 1, and anti-HPA-15b (n = 1.Conclusion: Our study indicates that anti-HPA-3, -HPA-5 and -HPA-15 antibodies seems to be the most platelet specific antibodies involved in FNAIT and PTR cases in Malaysian population. Since similar HPA allelic distribution among Malaysian and Indonesian populations have been observed, immunization against these three HPA systems are expected to be the most potential risk of alloimmune mediated platelet disorders in Indonesia.

  15. Resonance widths in open microwave cavities studied by harmonic inversion

    OpenAIRE

    Kuhl, U; Hoehmann, R.; Main, J.; Stoeckmann, H. -J.

    2007-01-01

    From the measurement of a reflection spectrum of an open microwave cavity the poles of the scattering matrix in the complex plane have been determined. The resonances have been extracted by means of the harmonic inversion method. By this it became possible to resolve the resonances in a regime where the line widths exceed the mean level spacing up to a factor of 10, a value inaccessible in experiments up to now. The obtained experimental distributions of line widths were found to be in perfec...

  16. Epithelial sodium channel modulates platelet collagen activation.

    Science.gov (United States)

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

    2014-03-01

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

  17. Approximation Algorithms for Directed Width Parameters

    CERN Document Server

    Kintali, Shiva; Kumar, Akash

    2011-01-01

    Treewidth of an undirected graph measures how close the graph is to being a tree. Several problems that are NP-hard on general graphs are solvable in polynomial time on graphs with bounded treewidth. Motivated by the success of treewidth, several directed analogues of treewidth have been introduced to measure the similarity of a directed graph to a directed acyclic graph (DAG). Directed treewidth, D-width, DAG-width, Kelly-width and directed pathwidth are some such parameters. In this paper, we present the first approximation algorithms for all these five directed width parameters. For directed treewidth and D-width we achieve an approximation factor of O(sqrt{logn}). For DAG-width, Kelly-width and directed pathwidth we achieve an O({\\log}^{3/2}{n}) approximation factor. Our algorithms are constructive, i.e., they construct the decompositions associated with these parameters. The width of these decompositions are within the above mentioned factor of the corresponding optimal width.

  18. The width of 5-dimensional prismatoids

    CERN Document Server

    Matschke, Benjamin; Weibel, Christophe

    2012-01-01

    Santos' construction of counter-examples to the Hirsch conjecture is based on the existence of prismatoids of dimension d of width greater than d. The case d=5 being the smallest one in which this can possibly occur, we here study the width of 5-dimensional prismatoids, obtaining the following results: - There are 5-prismatoids of width six with only 25 vertices, versus the 48 vertices in Santos' original construction. This leads to lowering the dimension of the non-Hirsch polytopes from 43 to only 20. - There are 5-prismatoids with n vertices and width \\Omega(n^(1/2)) for arbitrarily large n.

  19. Expansion of the neonatal platelet mass is achieved via an extension of platelet lifespan

    OpenAIRE

    Liu, Zhi-Jian; Hoffmeister, Karin M.; Hu, Zhongbo; Mager, Donald E.; Ait-Oudhia, Sihem; Debrincat, Marlyse A.; Pleines, Irina; Josefsson, Emma C.; Benjamin T Kile; Italiano, Joseph; Ramsey, Haley; Grozovsky, Renata; Veng-Pedersen, Peter; Chavda, Chaitanya; Sola-Visner, Martha

    2014-01-01

    Rapid growth and rising platelet counts result in a significant expansion of platelet mass during neonatal life.The rise in platelet counts is mediated by a prolongation in the neonatal platelet lifespan.

  20. 红细胞分布宽度检验在慢性心衰患者早期诊断中的应用效果观察%Clinical Effect Observation of Red Blood Cell Distribution Width Test in Early Diagnosis of Heart Failure in Patients with Chronic

    Institute of Scientific and Technical Information of China (English)

    巫雪飞; 李巧; 赵连山

    2015-01-01

    目的:研究红细胞分布宽度检验在慢性心力衰竭患者早期诊断中的意义。方法以我院2010年11月-2013年11月间收治的100例慢性心力衰竭作为研究对象,首先按照心力衰竭程度将其划入Ⅱ级、Ⅲ级、Ⅳ级心力衰竭组,另同时选择40例在我院同期体检健康人群作为对照组,检测四组患者的红细胞分布宽度,分析该数据与慢性心力衰竭之间的关系;随后按照红细胞分布宽度数据将患者分为<13.1%组、13.1%-14.5%组和>14.5%组,对比三组患者最终病死率的差异。结果:①健康组、Ⅱ级、Ⅲ级、Ⅳ级心力衰竭组的红细胞分布宽度数据分别为(11.63±0.71)%、(13.11±1.08)%、(14.31±1.52)%和(16.83±0.71)%,随着心力衰竭的程度提升,红细胞分布宽度越来越高,四组间比较,差异具备统计学意义(P<0.05);②红细胞分布宽度<13.1%组、13.1%-14.5%组和>14.5%组的死亡率分别为0.0%(0/45)、11.4%(4/35)、35.0%(7/20),红细胞分布宽度越大,患者的死亡率越高,,各组间病死率差异具有统计学意义(P<0.05)。结果检测慢性心力衰竭患者红细胞分布宽度,对于明确其疾病程度具有重要的意义,能够指导我们有效地评价疾病进程及治疗效果。%Objective To study the significance of red blood cell distribution width test in early diagnosis in patients with chronic heart failure.Methods 100 cases of chronic heart failure in our hospital in 2010 November-2013 year in November were treated as the research obj ect,first of all,according to the degree of heart failure put into II,III,IV heart failure group,the other while 40 cases in healthy people over the same period in our hospital physical examination as control group,four groups of patients with detection of red blood cell distribution width analysis of the

  1. PREGNANCY WITH PLATELET FUNCTION DISORDER

    Directory of Open Access Journals (Sweden)

    Sheila K

    2014-01-01

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

  2. Effects of hormones on platelet aggregation.

    Science.gov (United States)

    Farré, Antonio López; Modrego, Javier; Zamorano-León, José J

    2014-04-01

    Platelets and their activation/inhibition mechanisms play a central role in haemostasis. It is well known agonists and antagonists of platelet activation; however, during the last years novel evidences of hormone effects on platelet activation have been reported. Platelet functionality may be modulated by the interaction between different hormones and their platelet receptors, contributing to sex differences in platelet function and even in platelet-mediated vascular damage. It has suggested aspects that apparently are well established should be reviewed. Hormones effects on platelet activity are included among them. This article tries to review knowledge about the involvement of hormones in platelet biology and activity.

  3. Platelet aggregation following trauma

    DEFF Research Database (Denmark)

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

    2014-01-01

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

  4. Relationship of neutrophils lymphocyte ratio and red blood cell distribution width with idiopathic facial palsy%中性粒细胞淋巴细胞比及红细胞分布宽度与特发性面神经麻痹的关系

    Institute of Scientific and Technical Information of China (English)

    舒湘宁; 马跃文

    2016-01-01

    背景:红细胞分布宽度与C-反应蛋白一样,是机体炎症水平的一个标志,红细胞表面可能存在多种炎症因子受体,推测红细胞参与了炎症过程,炎症导致红细胞分布宽度增加。目的:分析中性粒细胞淋巴细胞比和红细胞分布宽度与特发性面神经麻痹的发病机制及发病时疾病的严重程度之间关系。方法:特发性面神经麻痹患者30例(实验组),使用HB(House and Brackmann Facial Grading System)评分和SB(Sunnybrook System)评分评估患者病情严重程度,将实验组按SB评分分为一般瘫痪组(30-100分)和严重瘫痪组(0-29分);按照HB评估结果分为轻度(Ⅱ/Ⅲ)、中度(Ⅳ)、重度瘫痪组(Ⅴ/Ⅵ)。同时选健康者32人做对照。对比各组间中性粒细胞淋巴细胞比、红细胞分布宽度指标的差异;分析SB评分和HB评估结果与中性粒细胞淋巴细胞比、红细胞分布宽度之间的相关性。结果与结论:实验组中性粒细胞淋巴细胞比值明显高于对照组(P<0.01);红细胞分布宽度在实验组不同疾病程度组间均存在显著差异,且与SB评分呈显著负相关(P <0.01),与HB评估等级呈显著正相关(P<0.01)。结果说明,实验组中性粒细胞淋巴细胞比值显著高于对照组,红细胞分布宽度与疾病严重程度呈正相关,提示特发性面神经麻痹发病机制与炎症相关,红细胞分布宽度指标可能对特发性面神经麻痹发病时疾病严重程度评估有参考意义。%BACKGROUND:Similarly with C-reactive protein, red blood cel distribution width can reflect the inflammatory process. Red blood cels involved in inflammatory process leads to the increase in red blood cel distribution width due to various inflammation factor receptors existingon the surface of red blood cel s. OBJECTIVE:To analyze the relationship between the neutrophils lymphocyte ratio, red blood cel distribution width and the pathogenesis andseverity

  5. Mean platelet volume in bipolar disorder: the search for an ideal biomarker

    Directory of Open Access Journals (Sweden)

    Mert DG

    2016-08-01

    Full Text Available Derya Guliz Mert,1 Hatice Terzi2 1Department of Psychiatry, 2Department of Hematology, Faculty of Medicine, Cumhuriyet University, Sivas, Turkey Background: The pathophysiology of bipolar disorder (BD remains a mystery. In this context, interest in the role of the immune and inflammatory systems in BD has been increasing. We aimed to compare the routine hemogram values of BD patients with those of the participants in the healthy control group, to assess the inflammation levels of the two groups. Mean platelet volume (MPV can be obtained as routine hemogram parameters and may aid in the detection of systemic inflammation. Subjects and methods: This study was conducted with BD (manic episode inpatients (n=132 and healthy controls (n=135. Abnormally distributed variables (ie, neutrophil–lymphocyte ratio [NLR], platelet–lymphocyte ratio [PLR], neutrophils, lymphocytes, hemoglobin, hematocrit [HCT], mean corpuscular volume [MCV], mean corpuscular hemoglobin [MCH], mean corpuscular hemoglobin concentration [MCHC], red cell distribution width [RDW], MPV, and plateletcrit [PCT] were compared using the Mann–Whitney U-test. Student’s t-test was used to compare the mean ages and white blood cell, red blood cell, and platelet counts of the patients with BD against those of the participants in the control group. Results: The comparisons revealed that while the mean WBC and the median NLR, PLR, neutrophil, lymphocyte, MPV, and PCT values were significantly higher in the patients with BD (P<0.05, the median hemoglobin, RBC, HCT, and MCHC values were significantly higher in the control group (P<0.05. Conclusion: Comparisons of hemogram values of patients with BD against those of the healthy control group revealed that inflammatory cells (absolute neutrophil count, platelet count, PCT, and MPV and ratios (NLR, PLR seem to be altered during manic episodes. These findings support the hypothesis that inflammatory activation occurs in BD during manic

  6. 14 CFR 121.95 - Route width.

    Science.gov (United States)

    2010-01-01

    .... (a) Approved routes and route segments over U.S. Federal airways or foreign airways (and advisory... designated width of those airways or routes. Whenever the Administrator finds it necessary to determine the width of other approved routes, he considers the following: (1) Terrain clearance. (2) Minimum en route...

  7. Constant Width Planar Computation Characterizes ACC0

    DEFF Research Database (Denmark)

    Hansen, Kristoffer Arnsfelt

    2006-01-01

    We obtain a characterization of ACC0 in terms of a natural class of constant width circuits, namely in terms of constant width polynomial size planar circuits. This is shown via a characterization of the class of acyclic digraphs which can be embedded on a cylinder surface in such a way that all...

  8. Constant Width Planar Computation Characterizes ACC0

    DEFF Research Database (Denmark)

    Hansen, K.A.

    2004-01-01

    We obtain a characterization of ACC 0 in terms of a natural class of constant width circuits, namely in terms of constant width polynomial size planar circuits. This is shown via a characterization of the class of acyclic digraphs which can be embedded on a cylinder surface in such a way that all...

  9. A Niche Width Model of Optimal Specialization

    NARCIS (Netherlands)

    Bruggeman, Jeroen; Ó Nualláin, Breanndán

    2000-01-01

    Niche width theory, a part of organizational ecology, predicts whether “specialist” or “generalist” forms of organizations have higher “fitness,” in a continually changing environment. To this end, niche width theory uses a mathematical model borrowed from biology. In this paper, we first loosen th

  10. 7 CFR 29.1085 - Width.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Width. 29.1085 Section 29.1085 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Heavy Fleshy Medium Thin Oil Lean Oily Rich Color intensity Pale Weak Moderate Strong Deep. Width...

  11. Platelets in inflammation and immunity.

    Science.gov (United States)

    Herter, J M; Rossaint, J; Zarbock, A

    2014-11-01

    The paradigm of platelets as mere mediators of hemostasis has long since been replaced by a dual role: hemostasis and inflammation. Now recognized as key players in innate and adaptive immune responses, platelets have the capacity to interact with almost all known immune cells. These platelet-immune cell interactions represent a hallmark of immunity, as they can potently enhance immune cell functions and, in some cases, even constitute a prerequisite for host defense mechanisms such as NETosis. In addition, recent studies have revealed a new role for platelets in immunity: They are ubiquitous sentinels and rapid first-line immune responders, as platelet-pathogen interactions within the vasculature appear to precede all other host defense mechanisms. Here, we discuss recent advances in our understanding of platelets as inflammatory cells, and provide an exemplary review of their role in acute inflammation.

  12. Estrogen, inflammation, and platelet phenotype.

    Science.gov (United States)

    Miller, Virginia M; Jayachandran, Muthuvel; Hashimoto, Kazumori; Heit, John A; Owen, Whyte G

    2008-01-01

    Although exogenous estrogenic therapies increase the risk of thrombosis, the effects of estrogen on formed elements of blood are uncertain. This article examines the genomic and nongenomic actions of estrogen on platelet phenotype that may contribute to increased thrombotic risk. To determine aggregation, secretion, protein expression, and thrombin generation, platelets were collected from experimental animals of varying hormonal status and from women enrolled in the Kronos Early Estrogen Prevention Study. Estrogen receptor beta predominates in circulating platelets. Estrogenic treatment in ovariectomized animals decreased platelet aggregation and adenosine triphosphate (ATP) secretion. However, acute exposure to 17beta-estradiol did not reverse decreases in platelet ATP secretion invoked by lipopolysaccharide. Thrombin generation was positively correlated to the number of circulating microvesicles expressing phosphatidylserine. Assessing the effect of estrogen treatments on blood platelets may lead to new ways of identifying women at risk for adverse thrombotic events with such therapies.

  13. Buried ion-exchanged glass waveguides: burial-depth dependence on waveguide width.

    Science.gov (United States)

    Madasamy, P; West, B R; Morrell, M M; Geraghty, D F; Honkanen, S; Peyghambarian, N

    2003-07-01

    A detailed theoretical and experimental study of the depth dependence of buried ion-exchanged waveguides on waveguide width is reported. Modeling, which includes the effect of nonhomogeneous time-dependent electric field distribution, agrees well with our experiments showing that burial depth increases linearly with waveguide width. These results may be used in the proper design of integrated optical circuits that need waveguides of different widths at different sections, such as arrayed waveguide gratings.

  14. 300例小儿支气管肺炎血小板参数的变化及临床意义%Alternation of platelet parameter in 300 children with bionchopneumonia

    Institute of Scientific and Technical Information of China (English)

    刘春艳; 贾鹏; 刘文君

    2012-01-01

    OBJECTIVE To investigate the alternation and clinical significance of platelet parameter in 300 children with bron-chopneumonia. METHODS Observed the alternation of 300 children patients with bronchopneumonia (severe pneumonia 130, mild pneumonia 170) platelet count (PLT), platelet hematocrit (PCT) , mean platelet volume (MPV), platelet distribution width (PDW), and compared it with 80 cases in normal control group. RESULTS The platelet parameters of severe pneumonia-group and mild pneumonia-group at acute stage were significantly higher than those of control group (P < 0.01); 4 platelet parameters in severe pneumonia group were significantly higher than mild pneumonia group at acute stage (P< 0.01); 4 platelet parameter in severe pneumonia梘roup and mild pneumonia group at convalescence stage were lower than those at acute stage (P < 0.01) and all indices came back to normal at convalescence stage. CONCLUSION The results of this study suggest that the 4 platelet parameters of children with bronchial pneumonia abnormally go up at acute stage the extent of rise is closely connected with the suite of an illness.%目的 探讨小儿支气管肺炎4项血小板参数的变化及意义.方法 观察300例小儿支气管肺炎(重症肺炎130例,轻症肺炎170例)患者的血小板计数(PLT)、血小板压积(PCT)、平均血小板体积(MPV)及血小板分布宽度(PDW)的变化,并与80例正常对照组比较.结果 重症肺炎组与轻症肺炎组急性期4项血小板参数比对照组均显著升高(P<0.01);重症肺炎组急性期4项血小板参数比轻症肺炎组急性期显著升高(P<0.01);重症肺炎组与轻症肺炎组恢复期4项血小板参数比急性期均显著降低(P<0.01),并恢复正常.结论 小儿支气管肺炎急性期4项血小板参数均异常升高,升高程度与病情相关.

  15. Complement Activation Alters Platelet Function

    Science.gov (United States)

    2015-12-01

    Award Number: W81XWH-12-1-0523 TITLE: Complement Activation Alters Platelet Function PRINCIPAL INVESTIGATOR: George Tsokos, M.D. CONTRACTING...Activation Alters Platelet Function 5a. CONTRACT NUMBER 5b. GRANT NUMBER W81XWH-12-1-0523 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) George Tsokos, M.D...a decreased level of disease. Further studies will expand upon these observations better outlining the function of platelets in the injury associated

  16. Platelet effects on ovarian cancer

    Science.gov (United States)

    Davis, Ashley; Afshar-Kharghan, Vahid; Sood, Anil K.

    2014-01-01

    Growing understanding of the role of thrombocytosis, high platelet turnover, and the presence of activated platelets in the circulation in cancer progression and metastasis has brought megakaryocytes into focus. Platelet biology is essential to hemostasis, vascular integrity, angiogenesis, inflammation, innate immunity, wound healing, and cancer biology. However, before megakaryocyte/platelet-directed therapies can be considered for clinical use, understanding of the mechanism and biology of paraneoplastic thrombocytosis in malignancy is required. Here, we provide an overview of the clinical implications, biological significance, and mechanisms of paraneoplastic thrombocytosis in the context of ovarian cancer. PMID:25023353

  17. Novel aspects of platelet aggregation

    Directory of Open Access Journals (Sweden)

    Roka-Moya Y. M.

    2014-01-01

    Full Text Available The platelet aggregation is an important process, which is critical for the hemostatic plug formation and thrombosis. Recent studies have shown that the platelet aggregation is more complex and dynamic than it was previously thought. There are several mechanisms that can initiate the platelet aggregation and each of them operates under specific conditions in vivo. At the same time, the influence of certain plasma proteins on this process should be considered. This review intends to summarize the recent data concerning the adhesive molecules and their receptors, which provide the platelet aggregation under different conditions.

  18. Overview of platelet physiology and laboratory evaluation of platelet function.

    Science.gov (United States)

    Rodgers, G M

    1999-06-01

    Appropriate laboratory testing for the platelet-type bleeding disorders hinges on an adequate assessment in the history and physical examination. Patients with histories and screening laboratory results consistent with coagulation disorders (hemophilia, disseminated intravascular coagulation) are not appropriate candidates for platelet function testing. In contrast, patients with a lifelong history of platelet-type bleeding symptoms and perhaps a positive family history of bleeding would be appropriate for testing. Figure 6 depicts one strategy to evaluate these patients. Platelet morphology can easily be evaluated to screen for two uncommon qualitative platelet disorders: Bernard-Soulier syndrome (associated with giant platelets) and gray platelet syndrome, a subtype of storage pool disorder in which platelet granulation is morphologically abnormal by light microscopy. If the bleeding disorder occurred later in life (no bleeding with surgery or trauma early in life), the focus should be on acquired disorders of platelet function. For those patients thought to have an inherited disorder, testing for vWD should be done initially because approximately 1% of the population has vWD. The complete vWD panel (factor VIII coagulant activity, vWf antigen, ristocetin cofactor activity) should be performed because many patients will have abnormalities of only one particular panel component. Patients diagnosed with vWD should be classified using multimeric analysis to identify the type 1 vWD patients likely to respond to DDAVP. If vWD studies are normal, platelet aggregation testing should be performed, ensuring that no antiplatelet medications have been ingested at least 1 week before testing. If platelet aggregation tests are normal and if suspicion for an inherited disorder remains high, vWD testing should be repeated. The evaluation of thrombocytopenia may require bone marrow examination to exclude primary hematologic disorders. If future studies with thrombopoietin assays

  19. Platelet Concentrates: Past, Present and Future

    OpenAIRE

    2011-01-01

    Platelets play a crucial role in hemostasis and wound healing, platelet growth factors are well known source of healing cytokines. Numerous techniques of autologous platelet concentrates have been developed and applied in oral and maxillofacial surgery. This review describes the evolution of the first and second generation of platelet concentrates (platelet rich plasma and platelet rich fibrin respectively) from their fore runner-fibrin sealants.

  20. Studies on megakaryopoiesis and platelet function

    OpenAIRE

    Meinders, M.

    2015-01-01

    Platelets are blood circulating specialized subcellular fragments, which are produced by megakaryocytes. Platelets are essential for hemostasis and wound healing but also play a role in non-hemostatic processes such as the immune response or cancer metastasis. Considering the immediate precursors of platelets, normal megakaryocyte development is essential for normal platelet function. Although much is known about platelet development, some aspects of platelet production remain poorly understo...

  1. Static vortices in long Josephson junctions of exponentially varying width

    Science.gov (United States)

    Semerdjieva, E. G.; Boyadjiev, T. L.; Shukrinov, Yu. M.

    2004-06-01

    A numerical simulation is carried out for static vortices in a long Josephson junction with an exponentially varying width. At specified values of the parameters the corresponding boundary-value problem admits more than one solution. Each solution (distribution of the magnetic flux in the junction) is associated to a Sturm-Liouville problem, the smallest eigenvalue of which can be used, in a first approximation, to assess the stability of the vortex against relatively small spatiotemporal perturbations. The change in width of the junction leads to a renormalization of the magnetic flux in comparison with the case of a linear one-dimensional model. The influence of the model parameters on the stability of the states of the magnetic flux is investigated in detail, particularly that of the shape parameter. The critical curve of the junction is constructed from pieces of the critical curves for the different magnetic flux distributions having the highest critical currents for the given magnetic field.

  2. Reduced neutron widths in the nuclear data ensemble: Experiment and theory do not agree

    CERN Document Server

    Koehler, P E

    2010-01-01

    I have analyzed reduced neutron widths ($\\Gamma_{n}^{0}$) for the subset of 1245 resonances in the nuclear data ensemble (NDE) for which they have been reported. Random matrix theory (RMT) predicts for the Gaussian orthogonal ensemble (GOE) that these widths should follow a $\\chi ^{2}$ distribution having one degree of freedom ($\

  3. Spin gated GDR widths at moderate temperatures

    Directory of Open Access Journals (Sweden)

    Mukul Ish

    2015-01-01

    Full Text Available We present the evolution of giant dipole resonance (GDR width as a function of angular momentum in the compound nucleus 144Sm in the temperature range of 1.5-2.0 MeV. The high energy γ rays emitted from the decay of excited 144Sm were measured using large NaI detector in coincidence with 4π sum spin spectrometer. GDR widths were found to comply with thermal shape fluctuation model in this temperature range over a wide range of spin. Experimental widths tend to increase rapidly at high angular momentum values.

  4. Porous Alumina Films with Width-Controllable Alumina Stripes

    Directory of Open Access Journals (Sweden)

    Huang Shi-Ming

    2010-01-01

    Full Text Available Abstract Porous alumina films had been fabricated by anodizing from aluminum films after an electropolishing procedure. Alumina stripes without pores can be distinguished on the surface of the porous alumina films. The width of the alumina stripes increases proportionally with the anodizing voltage. And the pores tend to be initiated close to the alumina stripes. These phenomena can be ascribed to the electric field distribution in the alumina barrier layer caused by the geometric structure of the aluminum surface.

  5. Porous Alumina Films with Width-Controllable Alumina Stripes.

    Science.gov (United States)

    Huang, Kai; Huang, Shi-Ming; Pu, Lin; Shi, Yi; Wu, Zhi-Ming; Ji, Li; Kang, Jun-Yong

    2010-08-21

    Porous alumina films had been fabricated by anodizing from aluminum films after an electropolishing procedure. Alumina stripes without pores can be distinguished on the surface of the porous alumina films. The width of the alumina stripes increases proportionally with the anodizing voltage. And the pores tend to be initiated close to the alumina stripes. These phenomena can be ascribed to the electric field distribution in the alumina barrier layer caused by the geometric structure of the aluminum surface.

  6. Ultrastructural characteristics of fibrin clots from canine and feline platelet concentrates activated with calcium gluconate or calcium gluconate plus batroxobin

    OpenAIRE

    Silva, Raúl F; Carmona, Jorge U; Rezende, Cleuza MF

    2013-01-01

    Background The aim of this study was to use transmission electron microscopy to describe the ultrastructural characteristics of clots obtained from canine and feline platelet concentrates (PC) that had been activated with calcium gluconate (CG) or CG plus batroxobin (CGB). Platelets from fibrin clots were classified according their morphological changes. The area of the intercellular space (μm2), the area of the fibrin fibers (μm2), and the width of the fibrin fibers (μm) were determined for ...

  7. Platelets, inflammation and tissue regeneration.

    Science.gov (United States)

    Nurden, Alan T

    2011-05-01

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

  8. On the Spectrum Width of Wind Waves

    Institute of Scientific and Technical Information of China (English)

    李陆平; 黄培基

    2001-01-01

    Based on the universal expression of wind wave spectra, four commonly used definitions of the spectrum width arere-examined. The results show that the non-dimensional spectrum width can measure the width of non-dimensionalspectra but it does not reflect the developing state of the spectra. The dimensional spectrum width expresses the degree ofconcentration of wave energy of the spectrum in the process of wind wave growth. Tests show that the spectrum widthpresented by Wen et al. can objectively measure the degree of concentration of wave energy of the spectrum, reflect thestate of wind wave growth, and provides a better result for practical application. The rules for definition of the spectrumwidth are discussed.

  9. Bipartite Graphs of Large Clique-Width

    Science.gov (United States)

    Korpelainen, Nicholas; Lozin, Vadim V.

    Recently, several constructions of bipartite graphs of large clique-width have been discovered in the literature. In the present paper, we propose a general framework for developing such constructions and use it to obtain new results on this topic.

  10. Accurate measurement of volume and shape of resting and activated blood platelets from light scattering

    Science.gov (United States)

    Moskalensky, Alexander E.; Yurkin, Maxim A.; Konokhova, Anastasiya I.; Strokotov, Dmitry I.; Nekrasov, Vyacheslav M.; Chernyshev, Andrei V.; Tsvetovskaya, Galina A.; Chikova, Elena D.; Maltsev, Valeri P.

    2013-01-01

    We introduce a novel approach for determination of volume and shape of individual blood platelets modeled as an oblate spheroid from angle-resolved light scattering with flow-cytometric technique. The light-scattering profiles (LSPs) of individual platelets were measured with the scanning flow cytometer and the platelet characteristics were determined from the solution of the inverse light-scattering problem using the precomputed database of theoretical LSPs. We revealed a phenomenon of parameter compensation, which is partly explained in the framework of anomalous diffraction approximation. To overcome this problem, additional a priori information on the platelet refractive index was used. It allowed us to determine the size of each platelet with subdiffraction precision and independent of the particular value of the platelet aspect ratio. The shape (spheroidal aspect ratio) distributions of platelets showed substantial differences between native and activated by 10 μM adenosine diphosphate samples. We expect that the new approach may find use in hematological analyzers for accurate measurement of platelet volume distribution and for determination of the platelet activation efficiency.

  11. Accurate measurement of volume and shape of resting and activated blood platelets from light scattering.

    Science.gov (United States)

    Moskalensky, Alexander E; Yurkin, Maxim A; Konokhova, Anastasiya I; Strokotov, Dmitry I; Nekrasov, Vyacheslav M; Chernyshev, Andrei V; Tsvetovskaya, Galina A; Chikova, Elena D; Maltsev, Valeri P

    2013-01-01

    We introduce a novel approach for determination of volume and shape of individual blood platelets modeled as an oblate spheroid from angle-resolved light scattering with flow-cytometric technique. The light-scattering profiles (LSPs) of individual platelets were measured with the scanning flow cytometer and the platelet characteristics were determined from the solution of the inverse light-scattering problem using the precomputed database of theoretical LSPs. We revealed a phenomenon of parameter compensation, which is partly explained in the framework of anomalous diffraction approximation. To overcome this problem, additional a priori information on the platelet refractive index was used. It allowed us to determine the size of each platelet with subdiffraction precision and independent of the particular value of the platelet aspect ratio. The shape (spheroidal aspect ratio) distributions of platelets showed substantial differences between native and activated by 10 μM adenosine diphosphate samples. We expect that the new approach may find use in hematological analyzers for accurate measurement of platelet volume distribution and for determination of the platelet activation efficiency.

  12. [ROLE α2-ADRENERGIC RECEPTORS IN REGULATION PLATELET REACTIVITY IN THE ELDERLY AT CHRONIC OBSTRUCTIVE PYELONEPHRITIS].

    Science.gov (United States)

    Barinov, E F

    2016-01-01

    Objective of the research was to determine involvement of platelets and the role of adrenaline in chronic inflammation maintaining and the initiation of acute inflammatory response in elderly patients with chronic obstructive pyelonephritis against this background. The study includes 60 patients with chronic obstructive pyelonephritis (COPN), which are distributed into two groups: basic - 22 elderly patients (age 73±1,5 years) and the comparison group - 38 middle-aged patients (52,5±2,4 years). The study excluded patients who took antiplatelet drugs and non-selective blockers of α adrenergic receptors at least 1 week before the study. Analysis of platelets adrenoreactivity in vitro was carried out at the time of hospitalization before the start of conservative therapy. Platelet-rich plasma was isolated from peripheral blood by centrifuging. ADP and epinephrine were used in the effective (EC50) and sub-threshold (EC10) concentrations to stimulate platelets. The formation of platelet-leukocyte aggregates was reproduced in vitro upon incubation of stimulated platelets (at a concentration of adrenaline EC50) and intact leukocytes isolated from patient peripheral blood. The study of platelet reactivity revealed that in elderly patients acute inflammatory response realization (relapse of COPN) is against optimal functioning of platelets α2 adrenergic receptors. Significant increase in the number of platelet-leukocyte aggregates is possible. Remission of COPN (the presence of chronic inflammation) in the examined patients of various ages was associated with platelet hypoadrenoreactivity. Increased platelet adrenoreactivity during transition from remission to relapse of COPN in the elderly patients is possible if adequate synthesis of ADP in platelets and its secretion from dense granules are preserved. The observed interaction of adrenaline and ADP with stimulated platelet hyporesponsiveness probably ensures adaptive response aimed at acute inflammatory response in

  13. A Comparative Study on the Relationship Between Inter Alar Width, and Inter Commissural Width on Circumferential Arc Width of Maxillary Anterior Teeth in Different Age Groups

    National Research Council Canada - National Science Library

    Kurien, Anjana; Cherian, K P; Mhatre, Shirley; Tharakan, Renji George

    2014-01-01

    This study was done to determine the relationship between interalar width and inter commissural width on circumferential arc width of maxillary anterior teeth in dentulous subjects between the age groups of 20–50 years...

  14. Analyzing the platelet proteome.

    Science.gov (United States)

    García, Angel; Zitzmann, Nicole; Watson, Steve P

    2004-08-01

    During the last 10 years, mass spectrometry (MS) has become a key tool for protein analysis and has underpinned the emerging field of proteomics. Using high-throughput tandem MS/MS following protein separation, it is potentially possible to analyze hundreds to thousands of proteins in a sample at a time. This technology can be used to analyze the protein content (i.e., the proteome) of any cell or tissue and complements the powerful field of genomics. The technology is particularly suitable for platelets because of the absence of a nucleus. Cellular proteins can be separated by either gel-based methods such as two-dimensional gel electrophoresis or one-dimensional sodium dodecyl sulfate polyacrylamide gel electrophoresis followed by liquid chromatography (LC) -MS/MS or by multidimensional LC-MS/MS. Prefractionation techniques, such as subcellular fractionations or immunoprecipitations, can be used to improve the analysis. Each method has particular advantages and disadvantages. Proteomics can be used to compare the proteome of basal and diseased platelets, helping to reveal information on the molecular basis of the disease.

  15. Comparison of tibiofemoral joint space width measurements from standing CT and fixed flexion radiography.

    Science.gov (United States)

    Segal, Neil A; Frick, Eric; Duryea, Jeffrey; Nevitt, Michael C; Niu, Jingbo; Torner, James C; Felson, David T; Anderson, Donald D

    2016-08-09

    The objective of this project was to determine the relationship between medial tibiofemoral joint space width measured on fixed-flexion radiographs and the three-dimensional joint space width distribution on low-dose, standing CT (SCT) imaging. At the 84-month visit of the Multicenter Osteoarthritis Study, 20 participants were recruited. A commercial SCT scanner for the foot and ankle was modified to image knees while standing. Medial tibiofemoral joint space width was assessed on radiographs at fixed locations from 15-30% of compartment width using validated software and on SCT by mapping the distances between three-dimensional subchondral bone surfaces. Individual joint space width values from radiographs were compared with three-dimensional joint space width values from corresponding sagittal plane locations using paired t-tests and correlation coefficients. For the 4 medial-most tibiofemoral locations, radiographic joint space width values exceeded the minimal joint space width on SCT by a mean of 2.0mm and were approximately equal to the 61st percentile value of the joint space width distribution at each respective sagittal-plane location. Correlation coefficients at these locations were 0.91-0.97 and the offsets between joint space width values from radiographs and SCT measurements were consistent. There were greater offsets and variability in the offsets between modalities closer to the tibial spine. Joint space width measurements on fixed-flexion radiographs are highly correlated with three-dimensional joint space width from SCT. In addition to avoiding bony overlap obscuring the joint, a limitation of radiographs, the current study supports a role for SCT in the evaluation of tibiofemoral OA. This article is protected by copyright. All rights reserved.

  16. a Linear Model for Meandering Rivers with Arbitrarily Varying Width

    Science.gov (United States)

    Frascati, A.; Lanzoni, S.

    2011-12-01

    Alluvial rivers usually exhibit quite complex planforms, characterized by a wide variety of alternating bends, that have attracted the interest of a large number of researchers. Much less attention has been paid to another striking feature observed in alluvial rivers, namely the relatively regular spatial variations attained by the channel width. Actively meandering channels, in fact, generally undergo spatial oscillations systematically correlated with channel curvature, with cross sections wider at bends than at crossings. Some other streams have been observed to exhibit irregular width variations. Conversely, rivers flowing in highly vegetated flood plains, i.e. canaliform rivers, may exhibit an opposite behavior, owing to the combined effects of bank erodibility and floodplain depositional processes which, in turn, are strictly linked to vegetation cover. Similarly to streamline curvatures induced by bends, the presence of along channel width variations may have remarkable effects on the flow field and sediment dynamics and, thereby, on the equilibrium river bed configuration. In particular, spatial distribution of channel curvature typically determines the formation of a rhythmic bar-pool pattern in the channel bed strictly associated with the development of river meanders. Channel width variations are on the contrary characterized by a sequence of narrowing, yielding a central scour, alternated to the downstream development of a widening associated with the formation of a central bar. Here we present a morphodynamic model that predict at a linear level the spatial distribution of the flow field and the equilibrium bed configuration of an alluvial river characterized by arbitrary along channel distributions of both the channel axis curvature and the channel width. The mathematical model is averaged over the depth and describes the steady, non-uniform flow and sediment transport in sinuous channels with a noncohesive bed. The governing two-dimensional equations

  17. Blood Donation Population Human Platelet Antigen of 1~5 System Gene Polymorphism Distribution Characteristics%献血人群人类血小板抗原1~5系统基因多态性分布特点

    Institute of Scientific and Technical Information of China (English)

    徐向华

    2015-01-01

    目的:探讨献血人群人类血小板抗原1~5系统基因多态性分布特点。方法采用聚合酶链-序列特异性引物技术(PCR-SSP)对200例无血缘关系的健康献血者进行HPA-1-5系统基因分型,分别计算献血人群的基因型及基因频率,分析其基因的多态性分布特点。结果该研究中献血人群HPA-1a、2a、3a、4a、5a基因频率分别为:0.942、0.741、0.926、0.945、0.773,HPA-1b、2b、3b、4b、5b基因频率分别为:0.058、0.286、0.084、0.045、0.227,各系统均呈多态性分布, ab杂合子依次为64和30例,-2bb4例;HPA-3和-15高度杂合,aa基因型依次为112和80例,很多献血人群属于bb基因型。结论该地区献血人群HPA-1-5系统基因均呈多态性分布,以HPA-3、-2和-5的a与b基因杂合率较高。%Objective To investigate the blood donation population human platelet antigen of 1 ~ 5 system gene polymorphism distribution characteristics.Methods Polymerase chain - sequence specific primers (PCR SSP) technology to the health of 200 cases of unrelated donors to HPA genotyping-1-5 system, gene frequency and genotype of the blood donation population are calculated respectively, analyze its gene polymorphism distribution characteristics.Results The study of blood donation population HPA - 1 a、2 a、3 a、4 a、5 a gene frequency are: 0.942、0.741、0.926、 0.741、0.926,HPA - 1 b、2 b、3 b、4 b、5 b gene frequencies are: 0.058、 0.286、0.084、0.286、0.084, are distributed in each system are polymorphism, ab heterozygous for 64 and 30 cases, in turn - 2 bb4 cases; HPA - 3 and 15 highly heterozygous, aa genotype was followed by 242 and 210, many line but people belong to the bb genotype. Conclusion This area crowd HPA - 1-5 blood donation system in gene polymorphism distribution of HPA - 3, 2 and 5 a and b gene hybrid rate is higher.

  18. γ射线辐照血小板不同保存时间质量参数变化分析%Quality parameters of platelets at different preservation time points after Gamma irradiation

    Institute of Scientific and Technical Information of China (English)

    冯冬梅

    2011-01-01

    目的 分析经γ射线辐照前后手工浓缩血小板和单采血小板在不同保存时间的CD62P、平均血小板体积(MPv)、分布宽度(PI)W)的变化.方法 随机选择手工浓缩血小板(PCs)和单采血小板(A-PCs)各20袋,每袋平均分为两份,其中一份经137铯辐照.剂量25Gy,另一份不辐照;在22℃±2℃的血小板恒温振荡保存箱内保存72h.经辐照的手工血小板和单采血小板分别设为观察组1、观察组2;不辐照的血小板分别设为对照组1、对照组2.流式细胞仪检测血小板辐照前及保存24h、72h后P选择素表达情况,全自动血球计数仪检测MPV、PDW.结果 辐照组与对照组血小板表达CD62P百分率均随保存时间延长而增高,保存72h后两组差异有统计学意义(P<0.01、P<0.05);辐照组与对照组的血小板随着保存时间的延长MPv、PDW逐渐增加,但相同时间段相比差异无统计学意义(P>0.05).结论 γ射线照射对血小板的质量无明显影响,但辐照后血小板应尽可能在72h内应用.%Objective To analyze the changes of CD62P, mean platelet volume(MPV), and platelet distribution width(PDW) at different preservation time points after gamma irradiation. Methods Twenty bags of concentrated platelets and 20 bags of apheresis platelets were randomly selected. The platelets in each bag were divided into two parts. One part was irradiated with 137 cesium at 25Gy and the other part was not irradiated. The two parts were preserved at 22℃±2℃ for 72h. The concentrated platelets and apheresis platelets were considered as irradiation groups 1 and 2, the platelets not irradiated were considered as control groups 1 and 2. Expression of CD62P in platelets was detected by flow cytometry before and 24 and 72h after irradiation, respectively. MPV and PDW were calculated with a blood counter. Results The expression rate of CD62P in platelets increased with the preservation time of platelets in both irradiation and control groups

  19. Platelets in inflammation and infection.

    Science.gov (United States)

    Jenne, Craig N; Kubes, Paul

    2015-01-01

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

  20. [Murine models of platelet diseases].

    Science.gov (United States)

    Lanza, F

    2007-05-01

    Platelet-related diseases correspond to functional defects or abnormal production (thrombopoiesis) of hereditary and immunological origins. Recent progress in the manipulation of the mouse genome (transgenesis, gene inactivation or insertion) has resulted in the generation of numerous strains exhibiting defective platelet function or production. Some strains reproduce known hereditary diseases affecting haemostasis (Glanzmann thrombasthenia, Bernard-Soulier syndrome (BSS) or thrombopoiesis (Wiscott-Aldrich or May-Hegglin syndrome). More often the mutated strains have no human equivalent and represent useful models to study: (i) the role of adhesive or signalling receptors or of signalling proteins in platelet-dependent haemostasis and thrombosis or; (ii) to study the poorly characterized mechanisms of thrombopoiesis, which implicate transcription factors (GATA, Fli1), growth factors and receptors (TPO, cMPL), and cytoskeletal or contractile proteins (tubulin, myosin). Additional mouse strains result from the selection of spontaneous mutants many of which affect intracellular platelet granules, representing models of storage pool diseases (SPD) such as the Gray platelet syndrome (alphaSPD) or Hermansky-Pudlack syndrome (deltaSPD). More recently, a systematic chemical mutagenesis approach has also identified genes involved in thrombopoiesis and platelet survival. Finally, mouse models of auto- or allo-immune thrombocytopenia have been developed to study the mechanisms of platelet destruction or removal.

  1. Platelet scintigraphy in atherothrombotic disease

    Energy Technology Data Exchange (ETDEWEB)

    Isaka, Yoshinari (Osaka National Hospital (Japan))

    1993-01-01

    Indium-111 platelet scintigraphy for the measurement of in vivo thrombogenicity is a useful noninvasive technique with a number of applications. From 1982 to 1989, we explored clinical relevance of this method for 576 consecutive patients with atherothrombotic disease. There was a disease-related difference in the percentage of positive platelet accumulation; 85% in patients with Dacron bifurcation graft, 75% in abdominal or thoracic aneurysm, 40% in intra-cardiac thrombi, 33% in arteriosclerosis obliterans and 25% in ischemic cerebrovascular disease. Labelled platelets accumulated frequently in the lesion with severe arteriographic abnormality. Aspirin clearly inhibited platelet accumulation on carotid atheroma but the effect of ticlopidine has been less conclusive. Short-term orally active PGI[sub 2] analogue had inhibitory effects on platelet accumulation in carotid atheroma and platelet aggregability, but did not cause significant reduction in plaque size. The results suggest the usefulness of platelet scintigraphy for monitoring the thrombogenicity in various atherothrombotic diseases. It will be necessary, however, to simplify the labelling procedures and to develop a new [sup 99m]Tc-labelled thrombus imaging agent, if thrombus imaging is to be considered for more generall use for patients with atherosclerosis. (author).

  2. Cyclosporine A enhances platelet aggregation.

    Science.gov (United States)

    Grace, A A; Barradas, M A; Mikhailidis, D P; Jeremy, J Y; Moorhead, J F; Sweny, P; Dandona, P

    1987-12-01

    In view of the reported increase in thromboembolic episodes following cyclosporine A (CyA) therapy, the effect of this drug on platelet aggregation and thromboxane A2 release was investigated. The addition of CyA, at therapeutic concentrations to platelet rich plasma from normal subjects in vitro was found to increase aggregation in response to adrenaline, collagen and ADP. Ingestion of CyA by healthy volunteers was also associated with enhanced platelet aggregation. The CyA-mediated enhancement of aggregation was further enhanced by the addition in vitro of therapeutic concentrations of heparin. Platelets from renal allograft recipients treated with CyA also showed hyperaggregability and increased thromboxane A2 release, which were most marked at "peak" plasma CyA concentration and less so at "trough" concentrations. Platelet hyperaggregability in renal allograft patients on long-term CyA therapy tended to revert towards normal following the replacement of CyA with azathioprine. Hypertensive patients with renal allografts on nifedipine therapy had normal platelet function and thromboxane release in spite of CyA therapy. These observations suggest that CyA-mediated platelet activation may contribute to the pathogenesis of the thromboembolic phenomena associated with the use of this drug. The increased release of thromboxane A2 (a vasoconstrictor) may also play a role in mediating CyA-related nephrotoxicity.

  3. FEM Analysis of Rolling Pressure Along Strip Width in Cold Rolling Process

    Institute of Scientific and Technical Information of China (English)

    LIU Xiang-hua; SHI Xu; LI Shan-qing; XU Jian-yong; WANG Guo-dong

    2007-01-01

    Using 3-D elastic-plastic FEM, the cold strip rolling process in a 4-high mill was simulated. The elastic deformation of rolls, the plastic deformation of the strip, and the pressure between the work roll and the backup roll were taken into account. The distribution of rolling pressure along the strip width was obtained. Based on the simulation results, the peak value of rolling pressure and the location of the peak were analyzed under different rolling conditions. The effects of the roll bending force and the strip width on the distribution of rolling pressure along the width direction were determined.

  4. Platelet enzyme abnormalities in leukemias

    Directory of Open Access Journals (Sweden)

    S Sharma

    2011-01-01

    Full Text Available Aim of the Study: The aim of this study was to evaluate platelet enzyme activity in cases of leukemia. Materials and Methods: Platelet enzymes glucose-6-phosphate dehydrogenase (G6PD, pyruvate kinase (PK and hexokinase (HK were studied in 47 patients of acute and chronic leukemia patients, 16 patients with acute myeloid leukemia (AML(13 relapse, three in remission, 12 patients with acute lymphocytic leukemia (ALL (five in relapse, seven in remission, 19 patients with chronic myeloid leukemia (CML. Results: The platelet G6PD activity was significantly low in cases of AML, ALL and also in CML. G6PD activity was normalized during AML remission. G6PD activity, although persistently low during ALL remission, increased significantly to near-normal during remission (P < 0.05 as compared with relapse (P < 0.01. Platelet PK activity was high during AML relapse (P < 0.05, which was normalized during remission. Platelet HK however was found to be decreased during all remission (P < 0.05. There was a significant positive correlation between G6PD and PK in cases of AML (P < 0.001 but not in ALL and CML. G6PD activity did not correlate with HK activity in any of the leukemic groups. A significant positive correlation was however seen between PK and HK activity in cases of ALL remission (P < 0.01 and CML (P < 0.05. Conclusions: Both red cell and platelet enzymes were studied in 36 leukemic patients and there was no statistically significant correlation between red cell and platelet enzymes. Platelet enzyme defect in leukemias suggests the inherent abnormality in megakaryopoiesis and would explain the functional platelet defects in leukemias.

  5. Platelet surface glutathione reductase-like activity.

    Science.gov (United States)

    Essex, David W; Li, Mengru; Feinman, Richard D; Miller, Anna

    2004-09-01

    We previously found that reduced glutathione (GSH) or a mixture of GSH/glutathione disulfide (GSSG) potentiated platelet aggregation. We here report that GSSG, when added to platelets alone, also potentiates platelet aggregation. Most of the GSSG was converted to GSH by a flavoprotein-dependent platelet surface mechanism. This provided an appropriate redox potential for platelet activation. The addition of GSSG to platelets generated sulfhydryls in the beta subunit of the alpha(IIb)beta(3) fibrinogen receptor, suggesting a mechanism for facilitation of agonist-induced platelet activation.

  6. Width of Sunspot Generating Zone and Reconstruction of Butterfly Diagram

    CERN Document Server

    Ivanov, V G; 10.1007/s11207-010-9665-6

    2010-01-01

    Based on the extended Greenwich-NOAA/USAF catalogue of sunspot groups it is demonstrated that the parameters describing the latitudinal width of the sunspot generating zone (SGZ) are closely related to the current level of solar activity, and the growth of the activity leads to the expansion of SGZ. The ratio of the sunspot number to the width of SGZ shows saturation at a certain level of the sunspot number, and above this level the increase of the activity takes place mostly due to the expansion of SGZ. It is shown that the mean latitudes of sunspots can be reconstructed from the amplitudes of solar activity. Using the obtained relations and the group sunspot numbers by Hoyt and Schatten (1998), the latitude distribution of sunspot groups ("the Maunder butterfly diagram") for the 18th and the first half of the 19th centuries is reconstructed and compared with historical sunspot observations.

  7. Reduction of track width in perpendicular magnetic recording

    Science.gov (United States)

    Xia, W.; Yamada, T.; Aoi, H.; Muraoka, H.; Nakamura, Y.

    2005-02-01

    In order to three dimensionally analyze perpendicular magnetic recording mechanisms, we have developed a program in which the magnetization of magnetic particles is introduced into calculations of magnetization distributions in a recording layer, based on the commercial software JMAG-Studio. Because this program was based on a FEM calculation, the head and media interactions and demagnetization during the recording process can be accurately modeled. Using this program, methods to reduce the recorded track width in perpendicular magnetic recording were investigated. Decreasing the magnetic spacing, the use of a side-shielded head structure and using media with weak exchange coupling are effective ways to reduce the track width in a single pole head and double-layer perpendicular media recording system.

  8. A Direct Measurement of the $W$ Decay Width

    Energy Technology Data Exchange (ETDEWEB)

    Vine, Troy [Univ. of College, London (United Kingdom)

    2008-08-01

    A direct measurement of the W boson total decay width is presented in proton-antiproton collisions at √s = 1.96 TeV using data collected by the CDF II detector. The measurement is made by fitting a simulated signal to the tail of the transverse mass distribution in the electron and muon decay channels. An integrated luminosity of 350 pb-1 is used, collected between February 2002 and August 2004. Combining the results from the separate decay channels gives the decay width as 2.038 ± 0.072 GeV in agreement with the theoretical prediction of 2.093 ± 0.002 GeV. A system is presented for the management of detector calibrations using a relational database schema. A description of the implementation and monitoring of a procedure to provide general users with a simple interface to the complete set of calibrations is also given.

  9. Constraints on widths of mixed pentaquark multiplets

    CERN Document Server

    Mohta, V

    2004-01-01

    We determine constraints on the partial widths of mixed pentaquark multiplets in the framework of heavy baryon chiral perturbation theory (HB$\\chi$PT). The partial widths satisfy a GMO-type relation at leading order in HB$\\chi$PT, for arbitrary mixing. The widths of N(1440), N(1710), and $\\Theta(1540)$ are not consistent with ideal mixing, $\\theta_{N} = 35.3^{\\circ}$, but are consistent with $\\theta_{N} \\lesssim 25^{\\circ}$. Furthermore, there are parameter values in HB$\\chi$PT that produce such a mixing angle while allowing the identification of the mass spectrum above. As an alternative to non-ideal mixing, we also suggest reasons for giving up on N(1440) as a pure pentaquark state.

  10. The Variable Line Width of Achernar

    CERN Document Server

    Rivinius, Th; Baade, D; Carciofi, A C; Leister, N; Štefl, S

    2016-01-01

    Spectroscopic observations of Achernar over the past decades, have shown the photospheric line width, as measured by the rotational parameter $v \\sin i$, to vary in correlation with the emission activity. Here we present new observations, covering the most recent activity phase, and further archival data collected from the archives. The $v \\sin i$ variation is confirmed. On the basis of the available data it cannot be decided with certainty whether the increased line width precedes the emission activity, i.e. is a signature of the ejection mechanism, or postdates is, which would make it a signature of re-accretion of some of the disk-material. However, the observed evidence leans towards the re-accretion hypothesis. Two further stars showing the effect of variable line width in correlation with emission activity, namely 66 Oph and $\\pi$ Aqr, are presented as well.

  11. Graph Operations on Clique-Width Bounded Graphs

    OpenAIRE

    Gurski, Frank

    2007-01-01

    Clique-width is a well-known graph parameter. Many NP-hard graph problems admit polynomial-time solutions when restricted to graphs of bounded clique-width. The same holds for NLC-width. In this paper we study the behavior of clique-width and NLC-width under various graph operations and graph transformations. We give upper and lower bounds for the clique-width and NLC-width of the modified graphs in terms of the clique-width and NLC-width of the involved graphs.

  12. Mechanisms of platelet-mediated liver regeneration.

    Science.gov (United States)

    Lisman, Ton; Porte, Robert J

    2016-08-04

    Platelets have multiple functions beyond their roles in thrombosis and hemostasis. Platelets support liver regeneration, which is required after partial hepatectomy and acute or chronic liver injury. Although it is widely assumed that platelets stimulate liver regeneration by local excretion of mitogens stored within platelet granules, definitive evidence for this is lacking, and alternative mechanisms deserve consideration. In-depth knowledge of mechanisms of platelet-mediated liver regeneration may lead to new therapeutic strategies to treat patients with failing regenerative responses.

  13. Platelets as delivery systems for disease treatments

    OpenAIRE

    Shi, Qizhen; Montgomery, Robert R.

    2010-01-01

    Platelets are small, anucleate, discoid shaped blood cells that play a fundamental role in hemostasis. Platelets contain a large number of biologically active molecules within cytoplasmic granules that are critical to normal platelet function. Because platelets circulate in blood through out the body, release biological molecules and mediators on demand, and participate in hemostasis as well as many other pathophysiologic processes, targeting expression of proteins of interest to platelets an...

  14. Doxorubicin-loaded platelets as a smart drug delivery system: An improved therapy for lymphoma

    Science.gov (United States)

    Xu, Peipei; Zuo, Huaqin; Chen, Bing; Wang, Ruju; Ahmed, Arsalan; Hu, Yong; Ouyang, Jian

    2017-01-01

    Chemotherapy is majorly used for the treatment of many cancers, including lymphoma. However, cytotoxic drugs, utilized in chemotherapy, can induce various side effects on normal tissues because of their non-specific distribution in the body. Natural platelets are used as drug carriers because of their biocompatibility and specific targeting to vascular disorders, such as cancer, inflammation, and thrombosis. In this work, doxorubicin (DOX) was loaded in natural platelets for treatment of lymphoma. Results showed that DOX was loaded into platelets with high drug loading and encapsulation efficiency. DOX did not significantly induce morphological and functional changes in platelets. DOX-platelet facilitated intracellular drug accumulation through “tumor cell-induced platelet aggregation” and released DOX into the medium in a pH-controlled manner. This phenomenon reduced the adverse effects and enhanced the therapeutic efficacy. The growth inhibition of lymphoma Raji cells was enhanced, and the cardiotoxicity of DOX was reduced when DOX was loaded in platelets. DOX-platelet improved the anti-tumor activity of DOX by regulating the expression of apoptosis-related genes. Thus, platelets can serve as potential drug carriers to deliver DOX for clinical treatment of lymphoma. PMID:28198453

  15. Micro-array profiling exhibits remarkable intra-individual stability of human platelet micro-RNA.

    Science.gov (United States)

    Stratz, C; Nührenberg, T G; Binder, H; Valina, C M; Trenk, D; Hochholzer, W; Neumann, F J; Fiebich, B L

    2012-04-01

    Platelets play an important role in haemostasis and thrombus formation. Latest research identified platelets harbouring so called microRNAs (miRNA). MiRNAs are short single-stranded RNAs modulating gene expression by targeting mRNAs. Limited data exist on inter-individual variability of platelet miRNA profile while no data are available on intra-individual variability. We assessed platelet miRNA profile in five volunteers at five time points over a time course of 10 days; 24 hours prior to the last blood sampling, subjects took 500 mg acetylsalicylic acid (ASA). Platelet miRNA was isolated from leucocyte-depleted platelet-rich plasma, and miRNA array-analysis was performed. Temporal patterns and ASA effect were explored by a linear mixed effects model for each miRNA. For the 20 most abundantly expressed platelet miRNAs, target gene search was performed and an annotation network was created. MiRNA expression profiling of 1,281 human miRNAs revealed relevant expression of 221 miRNAs consistently expressed in all samples at all time points. Correlation of platelet miRNA ranks was highly significant to other studies. Global distribution of miRNA expression was relatively similar in all subjects. No miRNA exhibited a significant effect of time at level 0.05. After 24 hours, no significant effect of ASA was found. Concerning functional implications of the 20 most abundantly expressed miRNAs, we found six functional themes. In conclusion, platelet miRNA profile is remarkably stable over the time period studied. Single-point analysis of platelet miRNA profile is reasonable when inter-individual differences are studied. The functional annotation network points toward extra-platelet effects of platelet miRNAs.

  16. Line width of Josephson flux flow oscillators

    DEFF Research Database (Denmark)

    Koshelets, V.P.; Dmitriev, P.N.; Sobolev, A.S.;

    2002-01-01

    to be proven before one initiates real FFO applications. To achieve this goal a comprehensive set of line width measurements of the FFO operating in different regimes has been performed. FFOs with tapered shape have been successfully implemented in order to avoid the superfine resonant structure with voltage...... spacing of about 20 nV and extremely low differential resistance, recently observed in the IVC of the standard rectangular geometry. The obtained results have been compared with existing theories and FFO models in order to understand and possibly eliminate excess noise in the FFO. The intrinsic line width...

  17. [Protein kinase C activation induces platelet apoptosis].

    Science.gov (United States)

    Zhao, Li-Li; Chen, Meng-Xing; Zhang, Ming-Yi; Dai, Ke-Sheng

    2013-10-01

    Platelet apoptosis elucidated by either physical or chemical compound or platelet storage occurs wildly, which might play important roles in controlling the numbers and functions of circulated platelets, or in the development of some platelet-related diseases. However, up to now, a little is known about the regulatory mechanisms of platelet apoptosis. Protein kinase C (PKC) is highly expressed in platelets and plays central roles in regulating platelet functions. Although there is evidence indicating that PKC is involved in the regulation of apoptosis of nucleated cells, it is still unclear whether PKC plays a role in platelet apoptosis. The aim of this study was to investigate the role of PKC in platelet apoptosis. The effects of PKC on mitochondrial membrane potential (ΔΨm), phosphatidylserine (PS) exposure, and caspase-3 activation of platelets were analyzed by flow cytometry and Western blot. The results showed that the ΔΨm depolarization in platelets was induced by PKC activator in time-dependent manner, and the caspase-3 activation in platelets was induced by PKC in concentration-dependent manner. However, the platelets incubated with PKC inhibitor did not results in ΔΨm depolarization and PS exposure. It is concluded that the PKC activation induces platelet apoptosis through influencing the mitochondrial functions and activating caspase 3. The finds suggest a novel mechanism for PKC in regulating platelet numbers and functions, which has important pathophysiological implications for thrombosis and hemostasis.

  18. Inherited platelet disorders and oral health.

    Science.gov (United States)

    Valera, Marie-Cécile; Kemoun, Philippe; Cousty, Sarah; Sie, Pierre; Payrastre, Bernard

    2013-02-01

    Platelets play a key role in thrombosis and hemostasis. Accumulation of platelets at the site of vascular injury is the first step in the formation of hemostatic plugs, which play a pivotal role in preventing blood loss after injury. Platelet adhesion at sites of injury results in spreading, secretion, recruitment of additional platelets, and formation of platelet aggregates. Inherited platelet disorders are rare causes of bleeding syndromes, ranging from mild bruising to severe hemorrhage. The defects can reflect deficiency or dysfunction of platelet surface glycoproteins, granule contents, cytoskeletal proteins, platelet pro-coagulant function, and signaling pathways. For instance, Bernard-Soulier syndrome and Glanzmann thrombasthenia are attributed to deficiencies of glycoprotein Ib/IX/V and GPIIb/IIIa, respectively, and are rare but severe platelet disorders. Inherited defects that impair platelet secretion and/or signal transduction are among the most common forms of mild platelet disorders and include gray platelet syndrome, Hermansky-Pudlak syndrome, and Chediak-Higashi syndrome. When necessary, desmopressin, antifibrinolytic agents, and transfusion of platelets remain the most common treatment of inherited platelet disorders. Alternative therapies such as recombinant activated factor VII are also available for a limited number of situations. In this review, we will discuss the management of patients with inherited platelet disorders in various clinical situations related to dental cares, including surgical intervention. © 2012 John Wiley & Sons A/S.

  19. Role of Platelet Parameters on Neovascular Glaucoma: A Retrospective Case-Control Study in China

    Science.gov (United States)

    Li, Shengjie; Cao, Wenjun; Sun, Xinghuai

    2016-01-01

    Purpose Retinal vein occlusion (RVO) and diabetic retinopathy (DR) are two major sight-threatening diseases which may lead to neovascular glaucoma (NVG). The aim of this study was to explore the association between platelet parameters and NVG. Methods A total of 185 subjects were enrolled for the study from January, 2012 to December, 2015 at the Eye-ENT Hospital of Fudan University. Patients include those with NVG secondary to RVO (RVO group, n = 38), patients with NVG secondary to DR (DR group, n = 47), diabetics mellitus without retinopathy (DM group, n = 52), and healthy individuals (control group, n = 48). A complete ophthalmological examination including visual field examination, A-scan ultrasound, Fundus photography, and measurement of platelet parameters were performed for NVG subjects. Results There was no statistical difference in the mean age and gender among the RVO, DR, and control groups (p>0.05). The mean level of platelet distribution width (PDW) was higher (p<0.001) in the RVO group (15.16±2.13fl) and DR group (16.17±1.66fl) when compared with the control group (13.77±2.99fl). The mean plateletcrit (PCT) value of the RVO group (0.229±0.063%) was also higher (p = 0.049) than the control group (0.199±0.045). In the DR group, mean platelet volume (MPV) value (10.72±1.57fl) was significantly higher (p = 0.002) than the control group (9.75±0.89fl). A similar trend was observed when platelet parameters were compared among the 3 groups with respect to age. The mean level of PDW was significantly higher (p<0.001) in the DR group (16.17±1.66fl) compared with the DM group (13.80±3.32fl). Stepwise multiple logistic regression analysis revealed that PDW (OR = 1.44, 95%CI = 1.149–1.805, p = 0.002) and MPV (OR = 1.503, 95%CI = 1.031–2.192, p = 0.034) were associated with the DR group, PDW (OR = 1.207, 95%CI = 1.010–1.443, p = 0.039) and PCT (OR = 1.663, 95%CI = 1.870–2.654, p = 0.036) were associated with the RVO group. Conclusion Our results

  20. Statistical characteristics of Doppler spectral width as observed by the conjugate SuperDARN radars

    Directory of Open Access Journals (Sweden)

    K. Hosokawa

    Full Text Available We performed a statistical analysis of the occurrence distribution of Doppler spectral width around the day-side high-latitude ionosphere using data from the conjugate radar pair composed of the CUTLASS Iceland-East radar in the Northern Hemisphere and the SENSU Syowa-East radar in the Southern Hemisphere. Three types of spectral width distribution were identified: (1 an exponential-like distribution in the lower magnetic latitudes (below 72°, (2 a Gaussian-like distribution around a few degrees magnetic latitude, centered on 78°, and (3 another type of distribution in the higher magnetic latitudes (above 80°. The first two are considered to represent the geophysical regimes such as the LLBL and the cusp, respectively, because they are similar to the spectral width distributions within the LLBL and the cusp, as classified by Baker et al. (1995. The distribution found above 80° magnetic latitude has been clarified for the first time in this study. This distribution has similarities to the exponential-like distribution in the lower latitude part, although clear differences also exist in their characteristics. These three spectral width distributions are commonly identified in conjugate hemispheres. The latitudinal transition from one distribution to another exhibits basically the same trend between two hemispheres. There is, however, an interhemispheric difference in the form of the distribution around the cusp latitudes, such that spectral width values obtained from Syowa-East are larger than those from Iceland-East. On the basis of the spectral width characteristics, the average locations of the cusp and the open/closed field line boundary are estimated statistically.

    Key words. Ionosphere (ionosphere-magnetosphere inter-actions; plasma convection – Magnetospheric physics (magnetopause, cusp, and boundary layers

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

    Science.gov (United States)

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

    2006-03-01

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

  2. Platelet-containing tantalum powders

    Energy Technology Data Exchange (ETDEWEB)

    Schiele, E.K.

    1988-04-26

    A method of forming platelet tantalum powders is described comprising the steps of: (a) providing an ingot-derived precursor tantalum powder, and (b) ball-milling the precursor powder for a time sufficient to form a platelet powder having an average FSSS of less than about 2 micrometers, a Scott density not greater than about 30 g/in/sup 3/ and a BET surface area of at least about 0.7 in/sup 2//g.

  3. Changes of platelet parameters in children with viral encephalitis%病毒性脑炎患儿血小板参数的动态改变

    Institute of Scientific and Technical Information of China (English)

    王同友; 王红兵; 朱冠南; 严义培

    2012-01-01

    Objective To explore the clinical value of platelet parameters including platelet count (PLT) , mean platelet volume ( MPV) , platelet distribution width ( PDW) and platelet - large cell ratio ( P - LCR) in children with viral encephalitis. Methods PLT, PDW, MPV and P - LCR were detected in 28 children with viral encephalitis in acute stage and recovery stage (viral encephalitis group ) and 30 healthy children ( control group ). Results MPV, PDW and P — LCR were significantly higher in the acute stage of viral encephalitis than in the recovery stage and healthy controls (P 0. 05 ). PLT showed no significant difference among the acute and recovery phase of viral en — cephalitis and control group (P >0.05 ). Conclusion The detection of platelet parameters is helpful in assessing the se -verity of disease and evaluating the efficacy of treatment for viral encephalitis in children .%目的 探讨血小板计数(PLT)、平均血小板体积(MPV)、血小板分布宽度(PDW) 和大血小板比例(P-LCR)在儿童病毒性脑炎(简称病脑)中的动态变化及其临床意义.方法 分别检测28例病脑急性期和恢复期患儿(病脑组)以及30例健康儿童(对照组)的PLT、MPV、PDW和P-LCR,并进行比较分析.结果 病脑急性期MPV、PDW、P-LCR水平高于病脑恢复期和对照组(P0.05); PLT在病脑急性期、恢复期及对照组间差异均无统计学意义(P>0.05).结论 血小板参数的检测有助于儿童病脑的病情评估和疗效监测.

  4. Correlation Widths in Quantum--Chaotic Scattering

    OpenAIRE

    Dietz, B.; Richter, A; WeidenmÜller, H.

    2011-01-01

    An important parameter to characterize the scattering matrix S for quantum-chaotic scattering is the width Gamma_{corr} of the S-matrix autocorrelation function. We show that the "Weisskopf estimate" d/(2pi) sum_c T_c (where d is the mean resonance spacing, T_c with 0

  5. Wireline equalization using pulse-width modulation

    NARCIS (Netherlands)

    Schrader, J.H.R.; Klumperink, Eric A.M.; Visschers, J.L.; Nauta, Bram

    2006-01-01

    Abstract-High-speed data links over copper cables can be effectively equalized using pulse-width modulation (PWM) pre-emphasis. This provides an alternative to the usual 2-tap FIR filters. The use of PWM pre-emphasis allows a channel loss at the Nyquist frequency of ~30dB, compared to ~20dB for a

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

    Directory of Open Access Journals (Sweden)

    Gupta Ashish

    2011-01-01

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

  7. Can platelet indices be used as predictors of complication in subjects with appendicitis?

    Science.gov (United States)

    Ceylan, Bahadır; Aslan, Turan; Çınar, Ahmet; Ruhkar Kurt, Ayşe; Akkoyunlu, Yasemin

    2016-12-01

    We examined the changes of mean platelet volume (MPV) and platelet distribution width (PDW) in subjects with appendicitis and whether MPV and PDW could be used to predict the development of complication due to appendicitis. The healthy control group, the cases of appendicitis with perforation, and the cases of appendicitis without perforation were compared with regard to MPV and PDW. We determined whether MPV and PDW were independent variables predictive of the development of complication in subjects with appendicitis. This retrospective case-control study included a total of 362 patients (249 of which were male (68.8 %) and 113 were female (31.2 %); median age, 30 [range, 18-84 years]). One hundred and ninety-two subjects (53 %) presented with appendicitis and 170 (47 %) comprised the healthy control group. Sixty-six (18.2 %) of the subjects with appendicitis developed complication. MPVs were lower in subjects of appendicitis without complication compared to the subjects of appendicitis with complication and the control group (MPV, 9.78 ± 0.99 vs. 10.20 ± 1.21 and 10.14 ± 1.03, respectively [p = 0.005]). The PDW levels were not different between the three groups. Independent variables predictive of the presence of complication included increased MPV and time from onset of symptoms to hospital presentation (odds ratio[confidence interval], p-value: 1.507[1.064-2.133], 0.021 and 18.887[5.139-69.410], 0.0001, respectively). Our findings suggested these, MPV values in cases of appendicitis without complication were lower than the cases with complication and healthy control and MPV is a predictor of the development of complication in subjects with appendicitis.

  8. Pulse width control loop as a duty cycle corrector

    Directory of Open Access Journals (Sweden)

    Jovanović Goran

    2004-01-01

    Full Text Available The clock distribution and generation circuitry forms a critical component of current synchronous digital systems. A digital system’s clocks must have not only low jitter, low skew, but also well-controlled duty cycle in order to facilitate versatile clocking techniques. In high-speed CMOS clock buffer design, the duty cycle of a clock is liable to be changed when the clock passes through a multistage buffer because the circuit is not pure digital [8]. In this paper, we propose a pulse width control loop referred as MPWCL (modified pulse width control loop that adopts the same architecture as the conventional PWCL, but with a new pulse generator and new charge pump circuit as a constituent of the duty cycle detector. Thanks to using new building blocks the proposed pulse width control loop can control the duty cycle in a wide range, and what is more important it becomes operative in saturation region too, what provides conditional for fast locking time. For 1.2 µm double-metal double-poly CMOS process with Vdd = 5 V and operating frequency of 133 MHz, results of SPICE simulation show that the duty cycle can be well controlled in the range from 20 % up to 80 % if the loop parameters are properly chosen.

  9. Predictors of the peak width for networks with exponential links

    Science.gov (United States)

    Troutman, B.M.; Karlinger, M.R.

    1989-01-01

    We investigate optimal predictors of the peak (S) and distance to peak (T) of the width function of drainage networks under the assumption that the networks are topologically random with independent and exponentially distributed link lengths. Analytical results are derived using the fact that, under these assumptions, the width function is a homogeneous Markov birth-death process. In particular, exact expressions are derived for the asymptotic conditional expectations of S and T given network magnitude N and given mainstream length H. In addition, a simulation study is performed to examine various predictors of S and T, including N, H, and basin morphometric properties; non-asymptotic conditional expectations and variances are estimated. The best single predictor of S is N, of T is H, and of the scaled peak (S divided by the area under the width function) is H. Finally, expressions tested on a set of drainage basins from the state of Wyoming perform reasonably well in predicting S and T despite probable violations of the original assumptions. ?? 1989 Springer-Verlag.

  10. Evidence of platelet activation in multiple sclerosis

    Directory of Open Access Journals (Sweden)

    Alexander J Steven

    2008-06-01

    Full Text Available Abstract 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 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.

  11. Channel width dependence of electrical characteristics of a-Si:H TFTs under bending stresses

    Science.gov (United States)

    Oh, Hyungon; Cho, Kyoungah; Kim, Sangsig

    2017-04-01

    In this study, we investigate the electrical characteristics of bendable a-Si:H thin-film transistors (TFTs) with various channel widths as a function of bending stress. Compared with a narrower channel TFT, a wider channel TFT exhibits a stable performance even at a bending strain of 1.3%. Our stress and strain distribution analysis reveals an inverse relationship between the channel width and the channel stress. As the channel width widens from 8 to 50 μm, the stress experienced by the middle channel region decreases from 545 to 277 MPa. Moreover, a 50 μm-channel-width TFT operates stably even after a 15 000 bending cycle while the 8 μm-channel-width TFT fails to operate after a 2000 bending cycle.

  12. Measurement of Pulse Width from a Bubble Cloud under Multibubble Sonoluminescence Conditions

    Science.gov (United States)

    Ko, Ilgon; Kwak, Ho-Young

    2010-12-01

    The pulse width from a bubble cloud under multibubble sonoluminescence (MBSL) conditions was measured for the first time using a time-correlated single photon counting technique (TC/SPC). The measured pulse width from several thousand bubbles in water was approximately 250.9 ps, with scattered pulses occurring 1.5 ns before and after the maximum light pulse intensity. The observed pulse width from a bubble cloud, which appears to be comparable to that of the single bubble sonoluminescence, indicates that the clouds of bubbles collapse simultaneous to emitting a light that is synchronized with the applied ultrasound. Also, pulse widths from clouds of multibubbles in water-surfactant and water-alcohol solutions were measured to investigate the surfactant and alcohol effect on the sonoluminescence intensity and pulse width. Size distribution of the bubble cloud at the multibubble conditions was also measured by phase-Doppler technique.

  13. Clinical significance and changes of platelet parameter in child patients with pneumonia%肺炎患儿血小板参数的变化及其临床意义

    Institute of Scientific and Technical Information of China (English)

    蒲秀红; 孔春新; 郭晓清; 安涛; 邱萌; 李茜; 吴琼

    2012-01-01

    目的 观察细菌、病毒、支原体所致轻、重症肺炎患儿血小板参数的变化并分析其临床意义.方法 回顾性研究2010年11月-2012年3月我科收治的180例细菌性、病毒性及支原体肺炎(各60例,其中重症肺炎62例,轻症肺炎118例)急性期和恢复期血小板计数(PLT)、血小板压积(PCT)、平均血小板体积(MPV)、血小板宽度(PDW)的变化,并与50例对照组进行比较.结果 三组肺炎患儿血小板参数均高于对照组,细菌性肺炎组患儿血小板参数明显高于病毒性肺炎组和支原体肺炎组(P<0.01);急性期重症肺炎患儿血小板参数明显高于轻症肺炎者(P<0.01),且两者均明显高于对照组;恢复期重症及轻症肺炎患儿血小板参数均明显降低,与对照组无差异.结论 肺炎患儿血小板数量及功能状态通常异常,以细菌性肺炎更易于发生;血小板参数的变化可作为肺炎严重程度及病情变化的一项参考指标.%Objective To investigate the changes and analyze the clinical significance of platelet parameter in child patients with pneumonia caused by microbe, virus and mycoplasma. Methods The medical records of 180 child patients ( including 62 cases of severe pneumonia, 118 cases of mild pneumonia) with microbial, viral and mycoplasma pneumonia from December 2010 to March 2011 were retrospectively reviewed ( including 60 cases of microbial pneumonia, 60 cases of viral pneumonia and 60 cases of mycoplasma pneumonia). The changes of platelet parameters such as platelet count ( PLT) , platelet hematocrit (PCT) , mean platelet volume (MPV) and platelet distribution width (PDW) in acute stage and in convalescence stage of patients with pneumonia were observed and compared with 50 cases normal control group. Results The platelet parameters of microbial pneumonia group, viral pneumonia group and mycoplasma pneumonia group were significantly higher than those of normal control group ( P < 0. 01 ) . The

  14. Platelet count in healthy subjects treated with antiplatelet drugs

    Directory of Open Access Journals (Sweden)

    Maczy González-Rincón

    2016-07-01

    Full Text Available Platelet count in peripheral blood of healthy subjects with antiplatelet drugs. 20 subjects were analized. They were distributed in two groups: subject A: 10 who received aspirin (100 mg and B:10 with Clopidogrel (75 mg for 7 days. In all subjects studied platelet count in peripheral blood and PRP. It found a platelet count before treatment with antiplatelet agents in peripheral blood of 258,6 ± 54,46 x 109 l and 7 days after 254 ± 41,86 x 109 l (aspirin and 285,4 ± 70, 196,5 ± 37,90 x 109 l (Clopidogrel respectively. In the PRP of subjects before receiving aspirin was 486,5 ± 129,54 x 109 l and after 449,2 ± 85,51 x 109 l; prior to Clopidogrel ingestion was 565,2 ± 150,41 and 592,9 ± 203,46 x 109 l after treatment. Significant differences were found only for the platelet count in the Clopidogrel Group (p < 0.05. A significant decrease in platelet count was observed in peripheral blood after administration of Clopidogrel, possibly as a result of its pharmacological mechanism. More studies are needed to assess a greater number of individuals and better measure the effect of antiplatelet agents.

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

    Science.gov (United States)

    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.

  16. Determination of volume, shape and refractive index of individual blood platelets

    CERN Document Server

    Kolesnikova, Irina V; Yurkin, Maxim A; Hoekstra, Alfons G; Maltsev, Valeri P; Semyanov, Konstantin A

    2008-01-01

    Light scattering patterns (LSP) of blood platelets were theoretically and experimentally analyzed. We used spicular spheroids as a model for the platelets with pseudopodia. The discrete dipole approximation was employed to simulate light scattering from an individual spicular spheroid constructed from a homogeneous oblate spheroid and 14 rectilinear parallelepipeds rising from the cell centre. These parallelepipeds have a weak effect on the LSP over the measured angular range. Therefore, a homogeneous oblate spheroid was taken as a simplified optical model for platelets. Using the T-matrix method, we computed the LSP over a range of volumes, aspect ratios and refractive indices. Measured LSPs of individual platelets were compared one by one with the theoretical set and the best fit was taken to characterize the measured platelets, resulting in distributions of volume, aspect ratio and refractive index.

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

    Directory of Open Access Journals (Sweden)

    Alice eAssinger

    2014-12-01

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

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

    Science.gov (United States)

    Assinger, Alice

    2014-01-01

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

  19. [Establishment of method detecting CD36 expression on human platelet and its application].

    Science.gov (United States)

    Liu, Ying; Xu, Xian-Guo; Lan, Xiao-Fei; Ma, Kai-Rong; Chen, Shu; Hong, Xiao-Zhen; He, Ji; Zhu, Fa-Ming; Lyu, Hang-Jun

    2013-08-01

    The individual with the deficiency of CD36 antigen on platelet displayed the risk of anti-CD36 immune reaction induced by transfusion, which is one of the reasons for platelet transfusion refractoriness (PTR). This study was purposed to detect the expression level of CD36 antigen on platelet by flow cytometry among apheresis platelet donors of Hangzhou area, and the frequency of CD36 deficiency was analyzed. Platelet-rich plasma (PRP) was separated from fresh anticoagulant whole blood by centrifugation, then the platelets were washed and adjusted to 1×10(6). The platelets were incubated with FITC-labeled CD36 and PE-labeled CD41 monoclonal antibodies, then the expression level of CD36 was detected by flow cytometry. The CD36 expression on monocytes for the samples of CD36-deficiency on the platelets was further analyzed. The results showed that 7 samples with CD36 antigen deficiency were found in 192 apheresis platelet donors. The frequency of CD36 deficiency was 3.6% and all of them were typeII deficiency. The significant difference of CD36 antigen expression was observed in the platelet donors of Hangzhou population, among them 59 individuals with low expressed CD36 antigen and 126 individuals with highly expressed CD36 antigen were found according to the geometric mean fluorescence intensity. It is concluded that the CD36 antigen deficient phenotype existed in the population, these data will provide the information for research of the CD36 antigen distribution and help to solve the platelet transfusion refractoriness.

  20. K- nuclear states: Binding energies and widths

    Science.gov (United States)

    Hrtánková, J.; Mareš, J.

    2017-07-01

    K- optical potentials relevant to calculations of K- nuclear quasibound states were developed within several chiral meson-baryon coupled-channels interaction models. The applied models yield quite different K- binding energies and widths. Then the K- multinucleon interactions were incorporated by a phenomenological optical potential fitted recently to kaonic atom data. Though the applied K- interaction models differ significantly in the K-N subthreshold region, our self-consistent calculations of kaonic nuclei across the periodic table lead to conclusions valid quite generally. Due to K- multinucleon absorption in the nuclear medium, the calculated widths of K- nuclear states are sizable, ΓK-≥90 MeV, and exceed substantially their binding energies in all considered nuclei.

  1. Radiative widths of neutral kaon excitations

    Indian Academy of Sciences (India)

    Sunil V Somalwar; KTeV Collaboration

    2004-03-01

    We observe 147 events of the axial vector pair $K_{1} (1270) - K_{1} (1400)$ produced in the Coulomb field of a Pb target and measure the radiative widths $ (K_{1} (1400) → K^{0} + ) = 280.8 ± 23.2$ (stat.) $± (40.4)$ (syst.) keV and $ (K_{1} (1270) → K^{0} + ) = 73.2 ± 6.1$ (stat.) $± 28.3$ (syst.) keV. These first measurements are lower than the quark-model predictions. We also place upper limits on the radiative widths for $K^{*} (1410)$ and $K_{2}^{*} (1430)$ and find that the letter is very small in accord with $SU(3)$ invariance in the naive quark model.

  2. Exotic Meson Decay Widths using Lattice QCD

    CERN Document Server

    Cook, M S

    2006-01-01

    A decay width calculation for a hybrid exotic meson h, with JPC=1-+, is presented for the channel h->pi+a1. This quenched lattice QCD simulation employs Luescher's finite box method. Operators coupling to the h and pi+a1 states are used at various levels of smearing and fuzzing, and at four quark masses. Eigenvalues of the corresponding correlation matrices yield energy spectra that determine scattering phase shifts for a discrete set of relative pi+a1 momenta. Although the phase shift data is sparse, fits to a Breit-Wigner model are attempted, resulting in a decay width of about 60 MeV when averaged over two lattice sizes.

  3. 中国牡丹江地区献血人群HPA基因分布特征的研究及数据库的建立%HPA Distribution Characteristics of Platelet Donor Population in Mudanjiang Area of China and Establishment of Its Database

    Institute of Scientific and Technical Information of China (English)

    刘丙现; 刘杰; 高广平; 王丹; 张彦; 于秀清; 夏冬梅; 周锐华; 郑华; 马嫱

    2012-01-01

    This study was aimed to explore the distribution characteristics of the human platelet antigen (HPA) gene of human platelet donors and its polymorphism in Mudanjiang area of Heilongjiang Province in China, to determine platelet antigen system with clinical significance by judging the rate of incompatibility of HPA, as well as to establish a database of donors'HPA. The genotyping of 154 unrelated platelet donors was performed by means of PCR-SSP. The frequencies of gene and genotype were calculated and compared with that in other areas. The results showed that the genes la - 17a of HPA-a were all expressed in the 154 healthy and unrelated platelet donors. Only genes 1b, 2b,3b,5b, 6b and 15b of HPA-b were expressed while genes 4b, 7b - 14b, 16b were not expressed. Among the genotypes, aa homozygosity was predominant and HPAI5 had the greatest heterozygosity, while HPA3 had lower heterozygosity. There were 23 combined types of HPA, 5 of them had a rate higher than 10% , and the frequencies of the other 18 were lower than 8%. HPA genotype frequencies showed a good consistence to Hardy-Weinberg equilibrium. It is concluded that the distribution of the allele polymorphism of HPAI ~HPA17 in Mudanjiang area has its own characteristics, compared with other areas and some countries, the local HPA genotype database of platelet donors is established in Mudanjiang area, which can provide the matching donors for clinical use with immunological significance.%本研究旨在探讨中国牡丹江地区献血人群HPA基因及其多态性分布特征,判断HPA抗原不配合比率,确定有临床意义的抗原系统,建立已知HPA基因型血小板献血者数据库.采用PCR- SSP方法对154名无血缘关系的献血者做HPA基因分型,计算基因频率与基因型频率,并与国内外不同人群进行比较.结果表明,154名健康、无血缘关系的献血者均表达出HPA-a基因中的1a -17a基因;仅表达HPA-b基因中的1b、2b、3b、5b、6b和15b,未表达HPA4

  4. W mass and width at the LHC.

    CERN Document Server

    Malberti, Martina

    2006-01-01

    The precision measurement of the W boson properties, such as its mass and width, constitutes an important consistency check of the Standard Model. This paper, in particular, describes methods to measure the W mass with improved precision at the Large Hadron Collider, exploiting the large number of Z bosons produced. The precision on the W boson mass achievable with an integrated luminosisty of 10~fb^-1 is discussed.

  5. Are there any good digraph width measures?

    CERN Document Server

    Ganian, Robert; Kneis, Joachim; Meister, Daniel; Obdržálek, Jan; Rossmanith, Peter; Sikdar, Somnath

    2010-01-01

    Several different measures for digraph width have appeared in the last few years. However, none of them shares all the "nice" properties of treewidth: First, being \\emph{algorithmically useful} i.e. admitting polynomial-time algorithms for all $\\MS1$-definable problems on digraphs of bounded width. And, second, having nice \\emph{structural properties} i.e. being monotone under taking subdigraphs and some form of arc contractions. As for the former, (undirected) $\\MS1$ seems to be the least common denominator of all reasonably expressive logical languages on digraphs that can speak about the edge/arc relation on the vertex set.The latter property is a necessary condition for a width measure to be characterizable by some version of the cops-and-robber game characterizing the ordinary treewidth. Our main result is that \\emph{any reasonable} algorithmically useful and structurally nice digraph measure cannot be substantially different from the treewidth of the underlying undirected graph. Moreover, we introduce \\...

  6. Platelet satellitism in infectious disease?

    Science.gov (United States)

    Laskaj, Renata; Sikiric, Dubravka; Skerk, Visnja

    2015-01-01

    Background Platelet satellitism is a phenomenon of unknown etiology of aggregating platelets around polymorphonuclear neutrophils and other blood cells which causes pseudothrombocytopenia, visible by microscopic examination of blood smears. It has been observed so far in about a hundred cases in the world. Case subject and methods Our case involves a 73-year-old female patient with a urinary infection. Biochemical serum analysis (CRP, glucose, AST, ALT, ALP, GGT, bilirubin, sodium, potassium, chloride, urea, creatinine) and blood cell count were performed with standard methods on autoanalyzers. Serum protein fractions were examined by electrophoresis and urinalysis with standard methods on autoanalyzer together with microscopic examination of urine sediment. Erythrocyte sedimentation rate, blood culture and urine culture tests were performed with standard methods. Results Due to typical pathological values for bacterial urinary infection, the patient was admitted to the hospital. Blood smear examination revealed phenomenon, which has persisted for three weeks after the disease has been cured. Blood smears with EDTA as an anticoagulant had platelet satellitism whereas the phenomenon was not observed in tubes with different anticoagulants (Na, Li-heparin) and capillary blood. Discussion We hypothesize that satellitism was induced by some immunological mechanism through formation of antibodies which have mediated platelets binding to neutrophil membranes and vice versa. Unfortunately we were unable to determine the putative trigger for this phenomenon. To our knowledge this is the second case of platelet satellitism ever described in Croatia. PMID:26110042

  7. 缺氧缺血性脑损害患儿血小板参数变化的临床研究%Changes of platelet parameters in children with hypoxic-ischemic brain damage*

    Institute of Scientific and Technical Information of China (English)

    罗世永; 苏国生; 劳炳焕

    2012-01-01

    Objective To investigate the clinical significance of changes of platelet parameters in children with hypoxic ischemic brain damage. Methods 63 cases of children with hypoxic ischemic encephalopathy were enrolled as experiment group,and 60 cases of asphyxia children without brain damage were enrolled as control group. Changes of platelet parameters in these two groups were compared. Results Platelet counts(PLT) in experiment group in acute stage and convalescent period were significantly lower than that in control group,but mean platelet volume(MPV) and platelet distribution width(PDW) were significantly higher. Conclusion There might be changes of platelet parameters in children with hypoxic ischemic encephalopathy and those asphyxia children without brain damage,and changes might be more obvious in former. Detection of platelet parameters could be helpful for monito ring disease condition.%目的 探讨缺氧缺血性脑损害患儿血小板参数变化的临床意义.方法 选取临床确诊缺氧缺血性脑病患儿63例作为实验组,同时选取同期发生窒息但无脑损害的患儿60例作为对照组,比较两组急性期和恢复期血小板参数的变化情况.结果 实验组血小板计数急性期和恢复期均低于对照组,两组比较差异具有统计学意义(P<0.05);平均血小板体积及血小板分布宽度急性期和恢复期均高于对照组,两组比较差异具有统计学意义(P<0.05).结论 缺氧缺血性脑病和窒息但无脑损害患儿血小板参数均有不同程度的变化,但缺氧缺血性脑病患儿变化程度较明显,临床可作为一个辅助的监测指标.

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

    Directory of Open Access Journals (Sweden)

    Neiva Teresinha J.C.

    2003-01-01

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

  9. Investigating the fluid mechanics behind red blood cell-induced lateral platelet motion

    Science.gov (United States)

    Crowl Erickson, Lindsay; Fogelson, Aaron

    2009-11-01

    Platelets play an essential role in blood clotting; they adhere to damaged tissue and release chemicals that activate other platelets. Yet in order to adhere, platelets must first come into contact with the injured vessel wall. Under arterial flow conditions, platelets have an enhanced concentration near blood vessel walls. This non-uniform cell distribution depends on the fluid dynamics of blood as a heterogeneous medium. We use a parallelized lattice Boltzmann-immersed boundary method to solve the flow dynamics of red cells and platelets in a periodic 2D vessel with no-slip boundary conditions. Red cells are treated as biconcave immersed boundary objects with isotropic Skalak membrane tension and an internal viscosity five times that of the surrounding plasma. Using this method we analyze the influence of shear rate, hematocrit, and red cell membrane properties on lateral platelet motion. We find that the effective diffusion of platelets is significantly lower near the vessel wall compared to the center of the vessel. Insight gained from this work could lead to significant improvements to current models for platelet adhesion where the presence of red blood cells is neglected due to computational intensity.

  10. CD8+ T cells induce platelet clearance in the liver via platelet desialylation in immune thrombocytopenia

    Science.gov (United States)

    Qiu, Jihua; Liu, Xuena; Li, Xiaoqing; Zhang, Xu; Han, Panpan; Zhou, Hai; Shao, Linlin; Hou, Yu; Min, Yanan; Kong, Zhangyuan; Wang, Yawen; Wei, Yu; Liu, Xinguang; Ni, Heyu; Peng, Jun; Hou, Ming

    2016-01-01

    In addition to antiplatelet autoantibodies, CD8+ cytotoxic T lymphocytes (CTLs) play an important role in the increased platelet destruction in immune thrombocytopenia (ITP). Recent studies have highlighted that platelet desialylation leads to platelet clearance via hepatocyte asialoglycoprotein receptors (ASGPRs). Whether CD8+ T cells induce platelet desialylation in ITP remains unclear. Here, we investigated the cytotoxicity of CD8+ T cells towards platelets and platelet desialylation in ITP. We found that the desialylation of fresh platelets was significantly higher in ITP patients with positive cytotoxicity of CD8+ T cells than those without cytotoxicity and controls. In vitro, CD8+ T cells from ITP patients with positive cytotoxicity induced significant platelet desialylation, neuraminidase-1 expression on the platelet surface, and platelet phagocytosis by hepatocytes. To study platelet survival and clearance in vivo, CD61 knockout mice were immunized and their CD8+ splenocytes were used. Platelets co-cultured with these CD8+ splenocytes demonstrated decreased survival in the circulation and increased phagocytosis in the liver. Both neuraminidase inhibitor and ASGPRs competitor significantly improved platelet survival and abrogated platelet clearance caused by CD8+ splenocytes. These findings suggest that CD8+ T cells induce platelet desialylation and platelet clearance in the liver in ITP, which may be a novel mechanism of ITP. PMID:27321376

  11. An overview of platelet indices and methods for evaluating platelet function in thrombocytopenic patients

    DEFF Research Database (Denmark)

    Vinholt, Pernille Just; Hvas, Anne-Mette; Nybo, Mads

    2014-01-01

    in thrombocytopenia. Flow cytometry, platelet aggregometry and platelet secretion tests are used to diagnose specific platelet function defects. The flow cytometric activation marker P-selectin and surface coverage by the Cone and Plate[let] analyser™ predict bleeding in selected thrombocytopenic populations...

  12. Platelet antigens and antibodies. Literature review

    Directory of Open Access Journals (Sweden)

    N. V. Mineeva

    2013-01-01

    Full Text Available Platelet antigens structure, role of platelet antibodies in the pathogenesis of various clinical conditions, characteristic of modern antibodies detection methods are presented in this article.

  13. Platelet antigens and antibodies. Literature review

    Directory of Open Access Journals (Sweden)

    N. V. Mineeva

    2014-07-01

    Full Text Available Platelet antigens structure, role of platelet antibodies in the pathogenesis of various clinical conditions, characteristic of modern antibodies detection methods are presented in this article.

  14. Effect of photodynamic therapy on mouse platelets

    Science.gov (United States)

    Zhou, Chuannong; Chi, Shunji; Deng, Jinsheng; Zhang, Hua; Liang, Junlin; Ha, Xian-wen

    1993-06-01

    Normal mice received hematoporphyrin derivative (HpD) i.v. prior to red light irradiation and the platelet-rich plasma was prepared and irradiated by red light. The platelets were processed for EM examination and stereological analysis. It was shown the 16 hrs after irradiation almost all platelets were necrotized; 8 hours after irradiation about one fourth of the platelets were necrotized and the remaining were considerably damaged. Immediately after irradiation a small number of platelets became necrotic and most other platelets were swollen and deformated, showing significantly increased mean area, perimeter and short axis, and mean cell volume and cell surface area. The findings indicate that platelets are highly sensitive to PDT action and can be directly and rapidly damaged by PDT even in the absence of vascular endothelial cells. The early platelet photoactivation may play an important role in the initiation of early vascular damage and microcirculatory alterations induced by PDT in vivo.

  15. Platelet Disorders: MedlinePlus Health Topic

    Science.gov (United States)

    ... Article: Erythropoietin and thrombopoietin mimetics: Natural alternatives to erythrocyte and platelet... Article: Detection of CALR Mutation in Clonal and Nonclonal Hematologic Diseases... Platelet Disorders -- see more articles Thrombocytopenias -- see more ...

  16. Level and width statistics of the open many-body systems

    Science.gov (United States)

    Mizutori, Shoujirou; Aiba, Hirokazu

    2016-06-01

    The level and width statistics of the two kinds of the random matrix models coupled to the continuum are analyzed. In the first model, the gaussian orthogonal ensemble with random couplings to the continuum, not only the width statistics deviate from the Porter-Thomas distribution due to the super-radiant mechanism, but also the distribution of the nearest neighbor level spacings shows deviation from the Wigner one simultaneously. In the second model, the two body random ensemble with correlated couplings to the continuum, the correlation between the target and the compound states leads to the global energy dependence of the widths. Within the narrow energy interval where states with widths deviating from the global energy dependence lie, the distributions behave similar way with the case of the random couplings. Namely, the deviation of statistics of the nearest neighbor level spacings from the Wigner distribution and the deviation of the width statistics from the Porter-Thomas distribution take place simultaneously within the models we investigated.

  17. Effect of platelet age on adhesiveness to collagen and platelet surface charge

    Energy Technology Data Exchange (ETDEWEB)

    Castellan, R.M.; Steiner, M.

    1976-11-30

    Adhesion to collagen was investigated as a function of platelet age in rat platelets. Platelet adherence was measured using EDTA-containing platelet- rich plasma which was added to preparations of collagen fibers clamped between magnetic stirrers by recording changes in light transmission. The plot of light transmission versus logarithm of time was linear and allowed calculation of a slope factor which related to the rate of adherence. Neither the amount of collagen nor the platelet count were limiting in the test. Young platelet populations (less than or equal to 1 day old) were obtained during the recovery phase from immune induced thrombocytopenia. Old platelet populations were prepared by blocking thrombopoiesis with cyclophosphamide. Young platelets did not differ significantly from randomly aged platelets in this function. The electrophoretic mobility of platelets was not affected by their age.

  18. Isolation and characterization of platelet-derived extracellular vesicles

    Directory of Open Access Journals (Sweden)

    Maria T. Aatonen

    2014-08-01

    Full Text Available Background: Platelet-derived extracellular vesicles (EVs participate, for example, in haemostasis, immunity and development. Most studies of platelet EVs have targeted microparticles, whereas exosomes and EV characterization under various conditions have been less analyzed. Studies have been hampered by the difficulty in obtaining EVs free from contaminating cells and platelet remnants. Therefore, we optimized an EV isolation protocol and compared the quantity and protein content of EVs induced by different agonists. Methods: Platelets isolated with iodixanol gradient were activated by thrombin and collagen, lipopolysaccharide (LPS or Ca2+ ionophore. Microparticles and exosomes were isolated by differential centrifugations. EVs were quantitated by nanoparticle tracking analysis (NTA and total protein. Size distributions were determined by NTA and electron microscopy. Proteomics was used to characterize the differentially induced EVs. Results: The main EV populations were 100–250 nm and over 90% were <500 nm irrespective of the activation. However, activation pathways differentially regulated the quantity and the quality of EVs, which also formed constitutively. Thrombogenic activation was the most potent physiological EV-generator. LPS was a weak inducer of EVs, which had a selective protein content from the thrombogenic EVs. Ca2+ ionophore generated a large population of protein-poor and unselectively packed EVs. By proteomic analysis, EVs were highly heterogeneous after the different activations and between the vesicle subpopulations. Conclusions: Although platelets constitutively release EVs, vesiculation can be increased, and the activation pathway determines the number and the cargo of the formed EVs. These activation-dependent variations render the use of protein content in sample normalization invalid. Since most platelet EVs are 100–250 nm, only a fraction has been analyzed by previously used methods, for example, flow cytometry. As

  19. Dengue platelets meet Sir Arthur Conan Doyle.

    Science.gov (United States)

    Bray, Paul F

    2013-11-14

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

  20. Molecular Basis Linking Platelet to Inflammation

    Institute of Scientific and Technical Information of China (English)

    马丽萍

    2010-01-01

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

  1. Platelets Inhibit Migration of Canine Osteosarcoma Cells.

    Science.gov (United States)

    Bulla, S C; Badial, P R; Silva, R C; Lunsford, K; Bulla, C

    2017-01-01

    The interaction between platelets and tumour cells is important for tumour growth and metastasis. Thrombocytopenia or antiplatelet treatment negatively impact on cancer metastasis, demonstrating potentially important roles for platelets in tumour progression. To our knowledge, there is no information regarding the role of platelets in cancer progression in dogs. This study was designed to test whether canine platelets affected the migratory behaviour of three canine osteosarcoma cell lines and to give insights of molecular mechanisms. Intact platelets, platelet lysate and platelet releasate inhibited the migration of canine osteosarcoma cell lines. Addition of blood leucocytes to the platelet samples did not alter the inhibitory effect on migration. Platelet treatment also significantly downregulated the transcriptional levels of SNAI2 and TWIST1 genes. The interaction between canine platelets or molecules released during platelet activation and these tumour cell lines inhibits their migration, which suggests that canine platelets might antagonize metastasis of canine osteosarcoma. This effect is probably due to, at least in part, downregulation of genes related to epithelial-mesenchymal transition. Copyright © 2016. Published by Elsevier Ltd.

  2. Platelet regulating properties of insulin revisited

    NARCIS (Netherlands)

    Andrade Ferreira, I. (Irlando)

    2005-01-01

    Disturbances in platelet responsiveness in diabetes mellitus (DM) lead to platelet-dependent complications in the vasculature. Our studies showed that insulin inhibits platelet activation by inhibiting ADP- and thrombin-induced Ca2+ levels. Ca2+ is under control of cAMP that is a potent endogenous p

  3. Image analysis of blood platelets adhesion.

    Science.gov (United States)

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

    2003-01-01

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

  4. Utrophins compensate for Dp71 absence in mdx3cv in adhered platelets.

    Science.gov (United States)

    Cerecedo, Doris; Mondragón, Ricardo; Candelario, Aurora; García-Sierra, Francisco; Mornet, Dominique; Rendón, Alvaro; Martínez-Rojas, Dalila

    2008-01-01

    Platelet adhesion is a critical step due to its hemostatic role in stopping bleeding after vascular damage. Short dystrophins are the most abundant dmd gene products in nonmuscle tissues, and in association with cytoskeleton proteins contribute to their intrinsic function; while utrophins are dystrophin-homologous related family proteins with structural and functional similarities. We previously demonstrated the presence of Dp71 isoforms, utrophins, and various dystrophin-associated proteins and their participation in cytoskeleton re-organization, filopodia and lamellipodia extension, and in centralizing cytoplasmic granules during the adhesion process of human platelets. To evaluate the morphologic changes and actin-based structures of mdx(3cv) platelets during the adhesion process, we compared the topographic distribution of Dp71d/Dp71Delta110(m) and dystrophin-associated protein in adhered platelets from dystrophic mdx(3cv) mouse. By confocal microscopy, we showed that absence of Dp71 isoforms in platelets from this animal model disrupted dystrophin-associated protein expression and distribution without modifying the platelet morphology displayed during the glass-adhesion process. By immunoprecipitation assays, we proved that up-regulated utrophins were associated with dystrophin-associated proteins to conform the dystrophin-associated protein complex corresponding to utrophins, which might compensate for Dp71 absence in mdx(3cv) platelets.

  5. Human platelet antigen genotyping of platelet donors in southern Brazil.

    Science.gov (United States)

    Merzoni, J; Fagundes, I S; Lunardi, L W; Lindenau, J D-R; Gil, B C; Jobim, M; Dias, V G; Merzoni, L; Sekine, L; Onsten, T G H; Jobim, L F

    2015-10-01

    Human platelet antigens (HPA) are immunogenic structures that result from single nucleotide polymorphisms (SNPs) leading to single amino acid substitutions. This study sought to determine the allele and genotype frequencies of HPA-1, HPA-2, HPA-3, HPA-4, HPA-5 and HPA-15 in platelet donors from the state of Rio Grande do Sul (RS), Brazil, and compare their allele frequencies to those observed in other populations. HPA genotyping was performed by PCR-SSP method. The study sample comprised 201 platelet donors (167 Caucasians and 34 non-Caucasians). Allele 'a' was that most commonly found for HPA-1 to 5 in both groups. The HPA-15ab genotype predominated over homozygous genotypes of this system. Fisher's exact test revealed statistically significant differences for the HPA-5 system, with a greater prevalence of the HPA-5b allele in non-Caucasians. The neighbour-joining method and principal components analysis revealed genetic proximity between our Caucasian group and European populations. We conclude that the allele frequencies of HPA-1 to 5 and HPA-15 found in our Caucasian sample are similar to those reported for European populations. These findings corroborate the ethnic makeup of the population of RS. The higher frequency of the HPA-5b allele found in the non-Caucasian group of our sample suggests the possibility of allosensitization in patients who receive platelet transfusions from genetically incompatible donors.

  6. Artifacts for Calibration of Submicron Width Measurements

    Science.gov (United States)

    Grunthaner, Frank; Grunthaner, Paula; Bryson, Charles, III

    2003-01-01

    Artifacts that are fabricated with the help of molecular-beam epitaxy (MBE) are undergoing development for use as dimensional calibration standards with submicron widths. Such standards are needed for calibrating instruments (principally, scanning electron microscopes and scanning probe microscopes) for measuring the widths of features in advanced integrated circuits. Dimensional calibration standards fabricated by an older process that involves lithography and etching of trenches in (110) surfaces of single-crystal silicon are generally reproducible to within dimensional tolerances of about 15 nm. It is anticipated that when the artifacts of the present type are fully developed, their critical dimensions will be reproducible to within 1 nm. These artifacts are expected to find increasing use in the semiconductor-device and integrated- circuit industries as the width tolerances on semiconductor devices shrink to a few nanometers during the next few years. Unlike in the older process, one does not rely on lithography and etching to define the critical dimensions. Instead, one relies on the inherent smoothness and flatness of MBE layers deposited under controlled conditions and defines the critical dimensions as the thicknesses of such layers. An artifact of the present type is fabricated in two stages (see figure): In the first stage, a multilayer epitaxial wafer is grown on a very flat substrate. In the second stage, the wafer is cleaved to expose the layers, then the exposed layers are differentially etched (taking advantage of large differences between the etch rates of the different epitaxial layer materials). The resulting structure includes narrow and well-defined trenches and a shelf with thicknesses determined by the thicknesses of the epitaxial layers from which they were etched. Eventually, it should be possible to add a third fabrication stage in which durable, electronically inert artifacts could be replicated in diamondlike carbon from a master made by

  7. Clique Cover Width and Clique Sum

    OpenAIRE

    Shahrokhi, Farhad

    2015-01-01

    For a clique cover $C$ in the undirected graph $G$, the clique cover graph of $C$ is the graph obtained by contracting the vertices of each clique in $C$ into a single vertex. The clique cover width of G, denoted by $CCW(G)$, is the minimum value of the bandwidth of all clique cover graphs of $G$. When $G$ is the clique sum of $G_1$ and $G_2$, we prove that $CCW(G) \\le 3/2(CCW(G_1) + CCW(G_2))$.

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

    Science.gov (United States)

    Pietersz, R N I

    2009-10-01

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

  9. Effect of ionizing radiation on platelet function in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Kalovidouris, A.E.; Papayannis, A.G. (Evangelismos Hospital, Athens (Greece))

    1981-01-01

    The effect of ionizing radiation on platelet function was investigated in vitro. Platelet-rich plasma (300x10/sup 9//l) was irradiated with doses of 1, 4, 10, 20 and 50 Gy. Platelet function tests were performed on both irradiated and control (non-irradiated) platelet samples. The platelet function tests were (1) platelet aggregation by ADP (1, 2, 4 ..mu..mol final concentration), adrenaline and collagen, (2) ADP-release from platelets, (3) clot retraction and (4) platelet factor-3 availability. It was found that roentgen irradiation of platelets in vitro did not affect these platelet function tests.

  10. Red cell distribution width and other red blood cell parameters with venous thromboembolism and mortality risk of patients with cancer%癌症患者红细胞分布宽度和其他的血红细胞参数与静脉血栓栓塞和死亡风险的相关性

    Institute of Scientific and Technical Information of China (English)

    杨文惠

    2015-01-01

    Objective:To analyze the correlation of red cell distribution width(RDW) and other red blood cell(RBC) parameters with venous thromboembolism risk and mortality rate in patients with cancer.Methods:RBC parameters of 1840 patients with cancer were detected.The main research result was the occurrence of venous thromboembolism(VTE) symptoms,and the secondary outcome was followed up for 2 years of death.Results:High RDW(more than 16%) and other red blood cells parameters were not associated with VET risk.High RDW increased the mortality risk.Conclusion:RDW and other RBC parameters have no independent correlation with VET risk of patients with cancer.And high RDW was a independent predictor of poor survival in patients with cancer.%目的:分析癌症患者红细胞分布宽度(RDW)及其他血红细胞(RBC)参数与静脉血栓栓塞风险和死亡率的相关性。方法:检测1840例癌症患者的RBC参数,主要研究结果是静脉血栓栓塞(VTE)症状的发生、次要结局是随访2年死亡。结果:高RDW(>16%)及其他血红细胞参数与VET风险无明显关联。高RDW增加死亡风险。结论:RDW及其他RBC参数与癌症患者VET风险无独立相关,而高RDW是癌症患者生存较差的独立预示因素。

  11. Optical antennas with sinusoidal modulation in width.

    Science.gov (United States)

    Dikken, Dirk Jan; Segerink, Frans B; Korterik, Jeroen P; Pfaff, Stefan S; Prangsma, Jord C; Herek, Jennifer L

    2016-08-08

    Small metal structures sustaining plasmon resonances in the optical regime are of great interest due to their large scattering cross sections and ability to concentrate light to subwavelength volumes. In this paper, we study the dipolar plasmon resonances of optical antennas with a constant volume and a sinusoidal modulation in width. We experimentally show that by changing the phase of the width-modulation, with a small 10 nm modulation amplitude, the resonance shifts over 160 nm. Using simulations we show how this simple design can create resonance shifts greater than 600 nm. The versatility of this design is further shown by creating asymmetric structures with two different modulation amplitudes, which we experimentally and numerically show to give rise to two resonances. Our results on both the symmetric and asymmetric antennas show the capability to control the localization of the fields outside the antenna, while still maintaining the freedom to change the antenna resonance wavelength. The antenna design we tested combines a large spectral tunability with a small footprint: all the antenna dimensions are factor 7 to 13 smaller than the wavelength, and hold potential as a design element in meta-surfaces for beam shaping.

  12. Platelets: crossroads of immunity and hemostasis.

    Science.gov (United States)

    Jenne, Craig N

    2014-07-31

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

  13. Evidence that platelet buoyant density, but not size, correlates with platelet age in man.

    Science.gov (United States)

    Mezzano, D; Hwang, K; Catalano, P; Aster, R H

    1981-01-01

    Following infusion of 51Cr-labeled autologous platelets into normal subjects, high-density (HD) and low-density (LD) platelet cohorts were isolated by prolonged centrifugation in isosmotic arabino-galactan (Stractan). Specific radio-activity of LD platelets declined rapidly post-infusion (T1/2 = 1.5 days), but specific radioactivity of HD platelets remained constant or increased over a 3--4-day period and gradually declined for 6--7 days thereafter. These differences were exaggerated when platelet cohorts enriched in LD or HD cells by slow centrifugation in high-density albumin were labeled and transfused. Mean survival of a platelet cohort enriched with HD cells was significantly (P less than 0.02) shorter (7.73 days) than that of a cohort enriched with LD cells (9.33) days). In normal subjects treated with aspirin, capacity for thromboxane synthesis was regained more rapidly (P less than 0.05) in LD than in HD platelets. HD and LD platelets differed only slightly in mean volume (HD platelets = 7.57 mu3, LD platelets = 6.87 mu3, 0.05 less than P less than 0.01). We believe the most logical interpretation of these findings is that under normal conditions in man, newly formed platelets are less dense on the average than total platelets and become more dense as they age in the circulation. Thus, specific radioactivity of LD platelets declines rapidly as these platelets move into a more dense compartment and are replaced by newly formed, unlabelled cells; specific radioactivity of HD platelets remains constant or increases as labelled platelets enter this compartment in numbers equal to or greater than the number leaving it at the end of their life span. The similarity in mean volumes of LD and HD platelets suggests that platelet size is unrelated to platelet age under normal conditions.

  14. Evidence that platelet buoyant density, but not size, correlates with platelet age in man

    Energy Technology Data Exchange (ETDEWEB)

    Mezzano, D.; Hwang, K.; Catalano, P.; Aster, R.H.

    1981-01-01

    Following infusion of 51Cr-labeled autologous platelets into normal subjects, high-density (HD) and low-density (LD) platelet cohorts were isolated by prolonged centrifugation in isosmotic arabino-galactan (Stractan). Specific radio-activity of LD platelets declined rapidly post-infusion (T1/2 . 1.5 days), but specific radioactivity of HD platelets remained constant or increased over a 3--4-day period and gradually declined for 6--7 days thereafter. These differences were exaggerated when platelet cohorts enriched in LD or HD cells by slow centrifugation in high-density albumin were labeled and transfused. Mean survival of a platelet cohort enriched with HD cells was significantly (P less than 0.02) shorter (7.73 days) than that of a cohort enriched with LD cells (9.33) days). In normal subjects treated with aspirin, capacity for thromboxane synthesis was regained more rapidly (P less than 0.05) in LD than in HD platelets. HD and LD platelets differed only slightly in mean volume (HD platelets . 7.57 mu3, LD platelets . 6.87 mu3, 0.05 less than P less than 0.01). We believe the most logical interpretation of these findings is that under normal conditions in man, newly formed platelets are less dense on the average than total platelets and become more dense as they age in the circulation. Thus, specific radioactivity of LD platelets declines rapidly as these platelets move into a more dense compartment and are replaced by newly formed, unlabelled cells; specific radioactivity of HD platelets remains constant or increases as labelled platelets enter this compartment in numbers equal to or greater than the number leaving it at the end of their life span. The similarity in mean volumes of LD and HD platelets suggests that platelet size is unrelated to platelet age under normal conditions.

  15. Platelets: bridging hemostasis, inflammation, and immunity.

    Science.gov (United States)

    Jenne, C N; Urrutia, R; Kubes, P

    2013-06-01

    Although the function of platelets in the maintenance of hemostasis has been studied in great detail, more recent evidence has highlighted a central role for platelets in the host inflammatory and immune responses. Platelets by virtue of their large numbers and their ability to rapidly release a broad spectrum of immunomodulatory cytokines, chemokines, and other mediators act as circulating sentinels. Upon detection of a pathogen, platelets quickly activate and begin to drive the ensuing inflammatory response. Platelets have the ability to directly modulate the activity of neutrophils (phagocytosis, oxidative burst), endothelium (adhesion molecule and chemokine expression), and lymphocytes. Due to their diverse array of adhesion molecules and preformed chemokines, platelets are able to adhere to leukocytes and facilitate their recruitment to sites of tissue damage or infection. Furthermore, platelets directly participate in the capture and sequestration of pathogens within the vasculature. Platelet-neutrophil interactions are known to induce the release of neutrophil extracellular traps (NETs) in response to either bacterial or viral infection, and platelets have been shown to internalize pathogens, sequestering them in engulfment vacuoles. Finally, emerging data indicate that platelets also participate in the host immune response by directly killing infected cells. This review will highlight the central role platelets play in the initiation and modulation of the host inflammatory and immune responses.

  16. Calpain Activator Dibucaine Induces Platelet Apoptosis

    Directory of Open Access Journals (Sweden)

    Jun Liu

    2011-03-01

    Full Text Available Calcium-dependent calpains are a family of cysteine proteases that have been demonstrated to play key roles in both platelet glycoprotein Ibα shedding and platelet activation and altered calpain activity is associated with thrombotic thrombocytopenic purpura. Calpain activators induce apoptosis in several types of nucleated cells. However, it is not clear whether calpain activators induce platelet apoptosis. Here we show that the calpain activator dibucaine induced several platelet apoptotic events including depolarization of the mitochondrial inner transmembrane potential, up-regulation of Bax and Bak, down-regulation of Bcl-2 and Bcl-XL, caspase-3 activation and phosphatidylserine exposure. Platelet apoptosis elicited by dibucaine was not affected by the broad spectrum metalloproteinase inhibitor GM6001. Furthermore, dibucaine did not induce platelet activation as detected by P-selectin expression and PAC-1 binding. However, platelet aggregation induced by ristocetin or α-thrombin, platelet adhesion and spreading on von Willebrand factor were significantly inhibited in platelets treated with dibucaine. Taken together, these data indicate that dibucaine induces platelet apoptosis and platelet dysfunction.

  17. Pulse width effect on the dissociation probability of CH4+ in the intense femtosecond laser field

    Institute of Scientific and Technical Information of China (English)

    WANG Gao; SONG Di; LIU Yuyan; KONG Fan'ao

    2006-01-01

    The laser pulse width effect on the dissociation probability of CH4+ irradiated by an ultrafast laser has been investigated experimentally and theoretically. The femtosecond laser at 800 nm with an intensity of 8.0 × 1013 W/cm2 was used. The observed relative yield of the primary fragment ion CH3+ increases with increasing pulse width and tends to saturate when the pulse width is longer than 120 fs. The field-assisted dissociation (FAD) model and quasi-classical trajectory (QCT) calculation were applied to predicting the dissociation probability of CH4+.The calculated probability is corrected with the molecular orientation effect and the spatial distribution of laser intensity. The modified results show that the dissociation requires at least 23 fs and saturates with long pulse widths (≥100 rs). The result is approximately consistent with the experimental observation.

  18. Device-width dependence of plateau width in quantum Hall states

    Science.gov (United States)

    Kawaji, S.; Hirakawa, K.; Nagata, M.

    1993-02-01

    Hall bar type devices having a total length of 2900 μm, a source and drain electrode width of 400 μm and different widths w ranging from 10 to 120 μm in its central 600 μm long part are fabricated from a GaAs/AlGaAs wafer with electron mobility of 21 m 2V -1s -1. The current at which the quantum Hall plateau for i=2 at B=9.7T at T=1.2K disappears is proportional to w. The average critical current density is Jcr=(1.6±0.2) A m -1

  19. Platelet-mediated cytotoxicity and its enhancement by platelet activating factor.

    Science.gov (United States)

    Bykovskaya, S N; Bolvacheva, A V; Kiselevsky, M V; Khaylenko, V A; Bykovsky, A F

    1991-01-01

    Platelet cytotoxicity was assessed in 70 cancer patients with various tumor localizations and in 30 normal donors. The data presented reveal that the ACL cell line displays the highest sensitivity to platelet cytotoxicity. Using the ACL cells, we discovered that platelets from oncological patients and normal donors display comparable cytotoxicity. The level of platelet lytic activity is irrelevant to tumor localisation; however, it appears to be dependent on the stage of tumor growth. Incubation of platelets, both from donors and patients, with PAF (concentration range 10 pM to 10 nM) results in a significant rise of the killing activity of platelets. PAF induces greater cytotoxicity enhancement for platelets with lower initial activity, this pattern appearing to be the specific feature of the PAF mediated effect. Hence, platelets can be considered as effector cells relevant to antitumor immunity; PAF-mediated enhancement of platelet cytotoxicity can appear to be useful in the search for new immunotherapeutic drugs.

  20. Prediction of concentrated flow width in ephemeral gully channels

    Science.gov (United States)

    Nachtergaele, J.; Poesen, J.; Sidorchuk, A.; Torri, D.

    2002-07-01

    Empirical prediction equations of the form W = aQb have been reported for rills and rivers, but not for ephemeral gullies. In this study six experimental data sets are used to establish a relationship between channel width (W, m) and flow discharge (Q, m3 s-1) for ephemeral gullies formed on cropland. The resulting regression equation (W = 2·51 Q0·412; R2 = 0·72; n = 67) predicts observed channel width reasonably well. Owing to logistic limitations related to the respective experimental set ups, only relatively small runoff discharges (i.e. Q flow channels revealed that the discharge exponent (flow shear stress distribution over the wetted perimeter between rills, gullies and rivers, (ii) a decrease in probability of a channel formed in soil material with uniform erosion resistance from rills over gullies to rivers and (iii) a decrease in average surface slope from rills over gullies to rivers.material. For both cases observed flow on cropland. For the frozen soils the equation

  1. Platelet function tests: a comparative review

    Directory of Open Access Journals (Sweden)

    Paniccia R

    2015-02-01

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

  2. Platelet Function Tests in Bleeding Disorders.

    Science.gov (United States)

    Lassila, Riitta

    2016-04-01

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

  3. Single injection of platelet-rich plasma as a novel treatment of carpal tunnel syndrome

    Directory of Open Access Journals (Sweden)

    Michael Alexander Malahias

    2015-01-01

    Full Text Available Both in vitro and in vivo experiments have confirmed that platelet-rich plasma has therapeutic effects on many neuropathies, but its effects on carpal tunnel syndrome remain poorly understood. We aimed to investigate whether single injection of platelet-rich plasma can improve the clinical symptoms of carpal tunnel syndrome. Fourteen patients presenting with median nerve injury who had suffered from mild carpal tunnel syndrome for over 3 months were included in this study. Under ultrasound guidance, 1-2 mL of platelet-rich plasma was injected into the region around the median nerve at the proximal edge of the carpal tunnel. At 1 month after single injection of platelet-rich plasma, Visual Analogue Scale results showed that pain almost disappeared in eight patients and it was obviously alleviated in three patients. Simultaneously, the disabilities of the arm, shoulder and hand questionnaire showed that upper limb function was obviously improved. In addition, no ultrasonographic manifestation of the carpal tunnel syndrome was found in five patients during ultrasonographic measurement of the width of the median nerve. During 3-month follow-up, the pain was not greatly alleviated in three patients. These findings show very encouraging mid-term outcomes regarding use of platelet-rich plasma for the treatment of carpal tunnel syndrome.

  4. Clay platelet partition within polymer blend nanocomposite films by EFTEM.

    Science.gov (United States)

    Linares, Elisângela M; Rippel, Márcia M; Galembeck, Fernando

    2010-12-01

    Transmission electron microscopy (TEM) is the main technique used to investigate the spatial distribution of clay platelets in polymer nanocomposites, but it has not often been successfully used in polymer blend nanocomposites because the high contrast between polymer phases impairs the observation of clay platelets. This work shows that electron spectral imaging in energy-filtered TEM (EFTEM) in the low-energy-loss spectral crossover region allows the observation of platelets on a clear background. Separate polymer domains are discerned by imaging at different energy losses, above and below the crossover energy, revealing the material morphology. Three blends (natural rubber [NR]/poly(styrene-butyl acrylate) [P(S-BA)], P(S-BA)/poly(vinyl chloride) [PVC], and NR/starch) were studied in this work, showing low contrast between the polymer phases in the 40-60 eV range. In the NR/P(S-BA) and P(S-BA)/PVC blend nanocomposites, the clay platelets accumulate in the P(S-BA) phase, while in the P(S-BA)/PVC nanocomposites, clay is also found at the interfaces. In the NR/starch blend, clay concentrates at the interface, but it also penetrates the two polymer phases. These observations reveal that nanostructured soft materials can display complex morphochemical patterns that are discerned thanks to the ability of EFTEM to produce many contrast patterns for the same sample.

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

    Directory of Open Access Journals (Sweden)

    Gupta Ashish

    2011-01-01

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

  6. Experimental Study on Lyophilization Preservation of Human Platelets Pretreated by Ultrasound%超声波预处理的人血小板冻干保存实验

    Institute of Scientific and Technical Information of China (English)

    范菊莉; 张绍志; 徐梦洁; 许先国; 陈光明

    2012-01-01

    Trehalose can be loaded into platelets cells by heat incubation, and ultrasound is employed to enhance the loading of trehalose into human platelets. Then treated platelets are freeze-dried and rehy-drated. The influence of the pre-treatment of ultrasound radiation on lyophilized platelets are studied, and the platelets only subjected to heat incubation are used as the controls. The results show that the in-tracellular trahalose concentration is (28. 9 ±4. 48) mmol/L after radiation for 30 min by ultrasound (frequency of 25 kHz, intensity of 0. 8 W/cm2). This concentration value is 118. 9% higher than that of the controls. And the treated platelets show normal characteristics by several hematology examination. After freeze-drying and rehydration, the recovery of the freeze-dried samples is (83. 3±4. 88) %, PDW is (18.9±1. 55)%, while for the control ones, the recovery and the PDW are (80. 8±4.54)% and (18. l± 15)%, respectively. There is no significant differences. Based on the experimental results, the ultrasound used as a pre-treatment of platelets lyophilization is feasible.%在热孵化的基础上增加超声波辐射以强化海藻糖载入血小板,将处理后的血小板进行冷冻干燥保存,以未经超声波辐射仅受热孵化预处理的血小板为对照组,研究超声波预处理对人血小板冻干保存的影响.结果表明,经25 kHz,0.8W/cm2的超声波辐射30 min的血小板细胞内海藻糖浓度达到(28.9士4.48)mmol/L,比对照组提高118.9%,超声处理后样品经血液学检测各项指标均为正常.两组血小板同时进行冻干后复水,经检验,样品组冻干血小板数值恢复率为(83.3±4.88)%,血小板分布宽度值(Platelet distribution width,PDW)为(18.9±1.55)%;对照组血小板数值恢复率为(80.8±4.54)%,PDW值为(18.1士1.15)%,两者不存在统计学差异.据此实验结果可以认为,超声波载糖法用于血小板冻干预处理是可行的,这为进一步进行血小板冻干研究提供了参考.

  7. Platelet receptors and patient responses: The contributions of Professor Stan Heptinstall to platelet research.

    Science.gov (United States)

    Clemetson, Kenneth J

    2015-01-01

    Stan Heptinstall's contributions to platelet research covered organising meetings at the national and European level as well as starting and maintaining the journal "Platelets". The major part of his research addressed problems of inhibition of platelet receptors and the effects of this on patient health. In particular, the effects of P2Y12 inhibitors on patients with acute cardiovascular problems were a major focus. Other studies included the effects of feverfew (Tanacetum parthenium) extracts on platelets, of direct anti-IIb/IIIa receptor (αIIbβ3) inhibitors and of prostanoids on platelet function. Recently, methods for assessing the effectiveness of platelet inhibition were investigated.

  8. Precision measurement of the mass and width of the W boson at CDF

    Energy Technology Data Exchange (ETDEWEB)

    Malik, Sarah Alam [Univ. College London, Bloomsbury (United Kingdom)

    2009-09-01

    A precision measurement of the mass and width of the W boson is presented. The W bosons are produced in proton antiproton collisions occurring at a centre of mass energy of 1.96 TeV at the Tevatron accelerator. The data used for the analyses is collected by the Collider Detector at Fermilab (CDF) and corresponds to an average integrated luminosity of 350 pb-1 for the W width analysis for the electron and muon channels and an average integrated luminosity of 2350 pb-1 for the W mass analysis. The mass and width of the W boson is extracted by fitting to the transverse mass distribution, with the peak of the distribution being most sensitive to the mass and the tail of the distribution sensitive to the width. The W width measurement in the electron and muon channels is combined to give a final result of 2032 ± 73 MeV. The systematic uncertainty on the W mass from the recoil of the W boson against the initial state gluon radiation is discussed. A systematic study of the recoil in Z → e+e- events where one electron is reconstructed in the central calorimeter and the other in the plug calorimeter and its effect on the W mass is presented for the first time in this thesis.

  9. Pulse-Width Jitter Measurement for Laser Diode Pulses

    Institute of Scientific and Technical Information of China (English)

    TANG Jun-Hua; WANG Yun-Cai

    2006-01-01

    @@ Theoretical analysis and experimental measurement of pulse-width jitter of diode laser pulses are presented. The expression of pulse power spectra with all amplitude jitter, timing jitter and pulse-width jitter is deduced.

  10. Lake Basin Fetch and Maximum Length/Width

    Data.gov (United States)

    Minnesota Department of Natural Resources — Linear features representing the Fetch, Maximum Length and Maximum Width of a lake basin. Fetch, maximum length and average width are calcuated from the lake polygon...

  11. [Studies of platelet aggregation in six cases of EDTA-dependent pseudothrombocytopenia].

    Science.gov (United States)

    Shimasaki, A; Kato, T; Ozaki, Y

    1994-06-01

    Peripheral blood count was performed by a Coulter Model S Plus STKR on six pseudothrombocytopenia patients (age: 16-70, 2 men and 4 women) using three different anticoagulants. Treatment with ethylene diamine tetraacetate (EDTA, 1 mg/ml) or sodium heparin (25 U/ml) aggregated platelets, but sodium citrate (3.8%, 1:9) had no effect. Smear examination revealed much platelet clumping but the satellite phenomenon was not present. No specific pattern was elucidated concerning cell size distribution curves between treatment by EDTA and heparin. Theophylline (10 mg/ml) and prostaglandin I2 (1 microM) inhibited EDTA-induced platelet aggregation but aspirin (1.8 mM) did not. On the other hand, these three substances inhibited heparin-induced platelet aggregation. These findings, taken together, suggested that EDTA and heparin initiated platelet activation and EDTA-induced platelet aggregation might be a process unrelated to thromboxane A2 production. Heparin may not be a suitable anticoagulant since it aggregates platelets of some healthy individuals.

  12. Platelet count and platelet indices in women with preeclampsia

    OpenAIRE

    AlSheeha MA; Alaboudi RS; Alghasham MA; Iqbal J; Adam I

    2016-01-01

    Muneera A AlSheeha,1 Rafi S Alaboudi,1 Mohammad A Alghasham,1 Javed Iqbal,2 Ishag Adam1 1Department of Obstetrics and Gynaecology, College of Medicine, Qassim University, Buriadah, 2Department of Obstetrics and Gynecology, Maternity and Children’s Hospital, Qassim, Kingdom of Saudi Arabia Background: Although the exact pathophysiology of preeclampsia is not completely understood, the utility of different platelets indices can be utilized to predict preeclampsia.Obj...

  13. Pathogen-Reduced, Platelet Additive Solution, Extended Stored Platelets (PREPS)

    Science.gov (United States)

    2015-10-01

    associated sepsis remains the principal lethal risk associated with platelet transfusion. Cold storage (4°C) is known to reduce post transfusion...and no residual radiation is detectable . *P-selectin samples will be prepped on end of storage day and batch tested. **Bacterial Culture sample...temperature controlled room until such time as they have no detectable residual radiation. This is generally about 3-4 months. At that point they are

  14. Detection of microbial contamination in platelets

    Science.gov (United States)

    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.

  15. Influence of Oxidative Stress on Stored Platelets

    Directory of Open Access Journals (Sweden)

    K. Manasa

    2016-01-01

    Full Text Available Platelet storage and its availability for transfusion are limited to 5-6 days. Oxidative stress (OS is one of the causes for reduced efficacy and shelf-life of platelets. The studies on platelet storage have focused on improving the storage conditions by altering platelet storage solutions, temperature, and materials. Nevertheless, the role of OS on platelet survival during storage is still unclear. Hence, this study was conducted to investigate the influence of storage on platelets. Platelets were stored for 12 days at 22°C. OS markers such as aggregation, superoxides, reactive oxygen species, glucose, pH, lipid peroxidation, protein oxidation, and antioxidant enzymes were assessed. OS increased during storage as indicated by increments in aggregation, superoxides, pH, conjugate dienes, and superoxide dismutase and decrements in glucose and catalase. Thus, platelets could endure OS till 6 days during storage, due to the antioxidant defense system. An evident increase in OS was observed from day 8 of storage, which can diminish the platelet efficacy. The present study provides an insight into the gradual changes occurring during platelet storage. This lays the foundation towards new possibilities of employing various antioxidants as additives in storage solutions.

  16. Effects of Physical (Inactivity on Platelet Function

    Directory of Open Access Journals (Sweden)

    Stefan Heber

    2015-01-01

    Full Text Available As platelet activation is closely related to the liberation of growth factors and inflammatory mediators, platelets play a central role in the development of CVD. Virtually all cardiovascular risk factors favor platelet hyperreactivity and, accordingly, also physical (inactivity affects platelet function. Within this paper, we will summarize and discuss the current knowledge on the impact of acute and habitual exercise on platelet function. Although there are apparent discrepancies regarding the reported effects of acute, strenuous exercise on platelet activation, a deeper analysis of the available literature reveals that the applied exercise intensity and the subjects’ cardiorespiratory fitness represent critical determinants for the observed effects. Consideration of these factors leads to the summary that (i acute, strenuous exercise can lead to platelet activation, (ii regular physical activity and/or physical fitness diminish or prevent platelet activation in response to acute exercise, and (iii habitual physical activity and/or physical fitness also favorably modulate platelet function at physical rest. Notably, these effects of exercise on platelet function show obvious similarities to the well-recognized relation between exercise and the risk for cardiovascular events where vigorous exercise transiently increases the risk for myocardial infarction and a physically active lifestyle dramatically reduces cardiovascular mortality.

  17. Trehalose lyophilized platelets for wound healing.

    Science.gov (United States)

    Pietramaggiori, Giorgio; Kaipainen, Arja; Ho, David; Orser, Cindy; Pebley, Walter; Rudolph, Alan; Orgill, Dennis P

    2007-01-01

    Fresh platelet preparations are utilized to treat a wide variety of wounds, although storage limitations and mixed results have hampered their clinical use. We hypothesized that concentrated lyophilized and reconstituted platelet preparations, preserved with trehalose, maintain and possibly enhance fresh platelets' ability to improve wound healing. We studied the ability of a single dose of trehalose lyophilized and reconstituted platelets to enhance wound healing when topically applied on full-thickness wounds in the genetically diabetic mouse. We compared these results with the application of multiple doses of fresh platelet preparations and trehalose lyophilized and reconstituted platelets as well as multiple doses of vascular endothelial growth factor (VEGF) and wounds left untreated. Trehalose lyophilized and reconstituted platelets, in single and multiple applications, multiple applications of fresh platelets and multiple applications of VEGF increased granulation tissue deposition, vascularity, and proliferation when compared with untreated wounds, as assessed by histology and immunohistochemistry. Wounds treated with multiple doses of VEGF and a single dose of freeze-dried platelets reached 90% closure faster than wounds left untreated. A single administration of trehalose lyophilized and reconstituted platelet preparations enhanced diabetic wound healing, therefore representing a promising strategy for the treatment of nonhealing wounds.

  18. Small RNAs as potential platelet therapeutics.

    Science.gov (United States)

    Edelstein, Leonard C; Bray, Paul F

    2012-01-01

    MicroRNAs (miRNAs) are 21-23 nucleotide RNAs that regulate more than 60% of mammalian protein coding genes. miRNAs play critical roles in hematopoiesis and megakaryocyte function and development. Platelets, in addition to possessing functional miRNA processing machinery, have miRNA levels that have been correlated with platelet reactivity, and these miRNAs have been shown to target mRNAs that encode proteins that alter platelet function. There are potential uses of platelet miRNA as biomarkers and therapeutic agents. Due to the ability of platelets to release miRNA-containing microparticles at sites of activation, including angiogenic regions, tumors, and atherosclerotic plaques, there is the possibility of engineering platelets to deliver miRNA-based therapies to these sites. Cellpreferential expression of miRNAs could be exploited to restrict transgene expression in hematopoietic stem cell gene therapy to the desired lineage, including megakaryocytes and platelets. Finally, manipulation of gene expression in stored platelets may allow more effective platelet storage. Although much work remains to be done, there is great potential in miRNA-based platelet therapies.

  19. Platelet MicroRNAs: An Overview.

    Science.gov (United States)

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

    2015-10-01

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

  20. Understanding platelet function through signal transduction.

    Science.gov (United States)

    Lazarus, Alan H; Song, Seng; Crow, Andrew R

    2003-01-01

    Platelets are activated by a number of stimuli resulting in the expression and/or activation of surface receptors, secretion of vasoactive substances, adhesion, aggregation, and finally thrombus formation. These events are propagated by a process known as transmembrane signaling, which relays the activating signal from the platelet membrane (eg, von Willebrand Factor binding to glycoprotein Ib) to the inside of the platelet which then serves to activate the platelet via a cascade of biochemical interactions. Inhibition of these transmembrane signaling molecules with a variety of available inhibitors or antagonists can in many cases prevent the platelet from becoming activated. An awareness of the mechanisms involved in platelet transmembrane signaling and the recent availability of new reagents to inhibit signaling may provide us with additional means to prevent platelet activation and perhaps even ameliorate the platelet storage lesion. This review will provide an introduction to the field of platelet transmembrane signaling and give an overview of some of the platelet signaling mechanisms that are relevant to transfusion medicine. Copyright 2003, Elsevier Science (USA). All rights reserved.

  1. Índices plaquetários em indivíduos com doença hepática alcoólica crônica Platelet indices in chronic alcoholic liver disease patients with thrombocytopenia

    Directory of Open Access Journals (Sweden)

    Ana Cláudia Costa

    2007-09-01

    Full Text Available OBJETIVO: Detectar alterações nos índices plaquetários em indivíduos com doença hepática alcoólica crónica e trombocitopenia e determinar o seu grau de correlação com outros parâmetros hematológicos. MÉTODOS: Foram estudados um total de 65 indivíduos, divididos em dois grupos: controlos (n = 35 e com doença hepática alcoólica crónica e trombocitopenia (n = 30. O grupo controlo foi emparelhado por idade e sexo com o grupo de doentes. A todos eles, foi efectuado hemograma completo, incluindo índices plaquetários. RESULTADOS: Os doentes com doença hepática alcoólica crónica apresentaram contagem de eritrócitos, leucócitos e plaquetas significativamente inferiores aos encontrados na população controlo. O mesmo se verificou com os valores de hemoglobina, hematócrito e valores absolutos de linfócitos e neutrófilos. O volume globular médio, a hemoglobina globular média e o RDW ("red cell distribution width" revelaram-se significativamente superiores no grupo de doentes. Relativamente aos índices plaquetários, foi encontrado aumento estatisticamente significativo do PDW ("platelet distribution width" e uma diminuição estatisticamente significativa no plaquetrócrito no grupo de doentes quando comparado com o grupo controlo. Em relação ao volume plaquetário médio não se encontraram diferenças estatisticamente significativas entre os dois grupos. Foi encontrada correlação estatisticamente significativa entre a contagem de plaquetas e os outros parâmetros hematológicos analisados. O plaquetrócito revelou-se o índice plaquetário que mais se relaciona com os restantes parâmetros hematológicos. CONCLUSÃO: Os doentes com doença hepática alcoólica crónica apresentam diminuição nas três linhas hematopoiéticas, possivelmente associada com o hiperesplenismo que estes doentes apresentam. Adicionalmente às alterações numéricas, encontraram-se alterações morfológicas a nível dos eritrócitos e

  2. Changing step width alters lower extremity biomechanics during running.

    Science.gov (United States)

    Brindle, Richard A; Milner, Clare E; Zhang, Songning; Fitzhugh, Eugene C

    2014-01-01

    Step width is a spatiotemporal parameter that may influence lower extremity biomechanics at the hip and knee joint. The purpose of this study was to determine the biomechanical response of the lower extremity joints to step width changes during running. Lower extremity data from 30 healthy runners, half of them male, were collected during running in three step width conditions: preferred, wide, and narrow. Dependent variables and step width were analyzed using a mixed model ANOVA and pairwise t-tests for post hoc comparisons. Step width was successfully altered in the wide and narrow conditions. Generally, frontal plane peak values decreased as step width increased from narrow to preferred to wide. Peak hip adduction and rearfoot eversion angles decreased as step width increased from narrow to wide. Peak knee abduction moment and knee abduction impulse also decreased as step width increased from narrow to wide. Although men and women ran differently, gender only influenced the effect of step width on peak rearfoot inversion moment. In conclusion, step width influences lower extremity biomechanics in healthy runners. When step width increased from narrow to wide, peak values of frontal plane variables decreased. In addition to previously reported changes at the rearfoot, the hip and knee joint biomechanics were also influenced by changes in step width.

  3. Platelet destruction in autoimmune thrombocytopenic purpura: kinetics and clearance of indium-111-labeled autologous platelets

    Energy Technology Data Exchange (ETDEWEB)

    Stratton, J.R.; Ballem, P.J.; Gernsheimer, T.; Cerqueira, M.; Slichter, S.J.

    1989-05-01

    Using autologous /sup 111/In-labeled platelets, platelet kinetics and the sites of platelet destruction were assessed in 16 normal subjects (13 with and three without spleens), in 17 studies of patients with primary autoimmune thrombocytopenic purpura (AITP), in six studies of patients with secondary AITP, in ten studies of patients with AITP following splenectomy, and in five thrombocytopenic patients with myelodysplastic syndromes. In normal subjects, the spleen accounted for 24 +/- 4% of platelet destruction and the liver for 15 +/- 2%. Untreated patients with primary AITP had increased splenic destruction (40 +/- 14%, p less than 0.001) but not hepatic destruction (13 +/- 5%). Compared with untreated patients, prednisone treated patients did not have significantly different spleen and liver platelet sequestration. Patients with secondary AITP had similar platelet counts, platelet survivals, and increases in splenic destruction of platelets as did patients with primary AITP. In contrast, patients with myelodysplastic syndromes had a normal pattern of platelet destruction. In AITP patients following splenectomy, the five nonresponders all had a marked increase (greater than 45%) in liver destruction compared to five responders (all less than 40%). Among all patients with primary or secondary AITP, there was an inverse relationship between the percent of platelets destroyed in the liver plus spleen and both the platelet count (r = 0.75, p less than 0.001) and the platelet survival (r = 0.86, p less than 0.001). In a stepwise multiple linear regression analysis, total liver plus spleen platelet destruction, the platelet survival and the platelet turnover were all significant independent predictors of the platelet count. Thus platelet destruction is shifted to the spleen in primary and secondary AITP. Failure of splenectomy is associated with a marked elevation in liver destruction.

  4. Detection of four platelet parameters in children with severe pneumonia and the significances%四项血小板参数在重症肺炎患儿中的检测及意义

    Institute of Scientific and Technical Information of China (English)

    马遵平; 李光贵

    2011-01-01

    Objective: To explore the detection of four platelet parameters in children with severe pneumonia and the significances. Methods: Sysmex SF 23000 analyzer was used to detect the plasma levels of platelet count ( PLT), mean platelet volume ( MPV), platelet distribution width ( PDW ) and platelet hematocrit (PCT) in 65 children with severe pneumonia and 60 normal healthy children. Results: The plasma levels of PLT, MPV, PDW and PCT in severe pneumonia group were significantly higher than those in control group (P <0. 05) . The plasma levels of PLT, MPV, PDW and PCT at recovery phase were significantly lower than those at acute phase (P < 0. 05 ) . Conclusion: The levels of PLT, MPV, PDW and PCT increase significantly in children with severe pneumonia, and the levels at acute phase are significantly higher than those at recovery phase, the changes of platelet parameters should be paid more attention to closely in clinic.%目的:探讨四项血小板参数在重症肺炎患儿中的检测及意义.方法:采用日本SysmexSF23000分析仪检测65例蓖症肺炎患儿和60例正常对照儿童血浆血小板计数(PLIT)、平均血小板体积(MPV)、血小板分布宽度(PDW)、血小板压积(PCT)水平.结果:重症肺炎组PLT、MPV、PDW、PCT明显高于对照组(P<0.05),恢复期组PLT、MPV、PDW、PCT明显低于急性期组(P<0.05).结论:重症肺炎患儿血小板四项参数PLT、MPV、PCT、PDW水平明显升高,并且急性期明显高于恢复期,临床应密切关注血小板参数变化.

  5. Clinical Significance of the Platelet Parameter in Children with Kawasaki Disease%川崎病患儿血小板参数变化及临床意义

    Institute of Scientific and Technical Information of China (English)

    梁慕琼

    2015-01-01

    目的:观察川崎病(KD)患儿血小板参数的变化,探讨其对冠状动脉病变(CAL)的提示作用。方法:将2013年1月至2014年6月收治的急性期川崎病患儿为观察组(n=42),再根据心脏彩超结果将川崎病患儿分为有 CAL 组(n=24)和无 CAL 组(n=18),以同期年龄匹配的健康体检儿童为对照组(n=40),比较各组血小板数量(PLT)、平均血小板体积(MPV)、血小板分布宽度(PDW)。结果:与对照组相比,观察组PLT显著增高,MPV和PDW 均显著下降(P 均<0.05);而川崎病并 CAL 组与无 CAL 组的 PLT、MPV 及 PDW 均无明显差异。结论:血小板参数中PLT、MPV及PDW 可协助诊断KD ,但不能预测CAL的发生。%Objective:To observe the changes of platelet parameters and the indicate action of coronary artery lesion (CAL)in patients with Kawasaki disease (KD). Method:42 patients with KD were classified as observation group(n=42) and divided into CAL group(n=24) and no CAL group(n=18) according to UCG,while health children were classified as control group(n=40).The platelet count(PLT),mean platelet volume(MPV) and platelet distribution width (PDW) were compared among the groups. Results:Compared with the control group,the PLT were significantly higher,but MPV and PDW were significantly lower in the observation group,all P<0.05. Meanwhile,the platelet parameters were no significant differences between the CAL group and no CAL group. Conclusions:The changes of platelet parameters may be help to the diagnose of KD, but had nothing to do with CAL.

  6. Platelet activation patterns in platelet size sub-populations: differential responses to aspirin in vitro.

    Science.gov (United States)

    Mangalpally, Kiran Kumar R; Siqueiros-Garcia, Alan; Vaduganathan, Muthiah; Dong, Jing-Fei; Kleiman, Neal S; Guthikonda, Sasidhar

    2010-10-01

    Circulating platelets are heterogeneous in size and structure. Whether this translates into differences in platelet function and efficacy of antiplatelet therapy is unclear. Hence, we decided to investigate the activation patterns among different platelet populations differentiated by size, and to compare the inhibitory effects of aspirin in these populations. Circulating platelets from 9 healthy volunteers were separated by size and stratified into the largest and smallest quintiles. Platelets were stimulated with 75 μM arachidonic acid (AA), 10 μM ADP or 25 μM TRAP. Alpha-granule protein secretion and expression (P-selectin, VWF, fibrinogen), surface-protein activation (activated integrin αIIbβ3) were assessed. Platelet thromboxane B(2) (TxB(2)) synthesis following AA stimulation was measured in vitro before and after incubation with 265 μM aspirin. Reticulated (juvenile) platelets were assessed using thiazole orange staining. A greater number of large platelets in the largest quintile were reticulated compared with the smallest quintile (6.1 ± 2.8% vs. 1.2 ± 1.5% respectively, p aspirin (1029 ± 190 pg/mL vs. 851 ± 159 pg/mL, respectively, p = 0.03). After stimulation with each agonist, a greater proportion of large platelets bound fibrinogen, VWF, P-selectin and activated integrin αIIbβ3 than small platelets both in the presence and in the absence of in vitro aspirin. In an in vitro setting, large platelets appear to be more active than small platelets and continue to be more active even after in vitro aspirin. Platelets exhibit heterogeneity in size and structure. Whether this translates into platelet function and efficacy of antiplatelet therapy is unclear. We evaluated platelet functional properties and the effects of aspirin on separated platelet subpopulations in an in vitro setting. Platelets were sorted into the largest and smallest size quintiles using flow cytometry forward scatter. Alpha-granule protein release, dense granule content

  7. 红细胞分布宽度对PCI治疗AMI患者心肌灌注不良的预测价值%Predictive value of red cell distribution width on poor myocardial perfusion in patients with acute myo-cardial infarction treated by PCI

    Institute of Scientific and Technical Information of China (English)

    王献忠; 朱国英; 张利峰; 李延民

    2016-01-01

    目的:研究红细胞分布宽度(RDW)对经皮冠脉介入(PCI)治疗的急性心肌梗死(AMI)患者心肌灌注不良的预测价值.方法:自2013年8月至2015年8月,选择在我院接受PCI治疗的212例ACS患者进行研究.根据血液分析仪的RDW检测结果,患者被分为RDW50%记为心肌灌注良好组(134例).比较两组患者的临床资料,并对心肌灌注影响因素进行单因素及多因素分析.结果:与RD W50% were regar- ded as good myocardial perfusion group (n=134).Clinical data were compared between two groups,and single fac- tor and multi-factor analysis were used to analyze influencing factors for myocardial perfusion.Results:Compared with RDW<13.0% group,there were significant rise in age [(62.85±5.23)years vs.(67.33±6.17)years],and significant reductions in left ventricular ejection fraction [LVEF,(52.37±6.14)% vs.(50.55±5.53)%]and STR [(0.73±0.26)vs.(0.57±0.39)]in RDW≥13.0% group,P<0.05 or <0.01. Compared with good myocardial perfusion group,there were significant reductions in percentage of RDW<13% (59.70% vs.44.87%)and LVEF [(52.25±3.81)% vs.(50.29 ± 4.08)%],and significant rise in age [(63.29 ± 1.93)years vs.(66.42 ± 2.15) years]in poor myocardial perfusion group,P<0.05 all.Multi-factor Logistic regression analysis indicated that age, LVEF and RDW were independent predictors for poor myocardial perfusion (r=3.826~6.525,P<0.01 all).Con-clusion:Red cell distribution width possesses good predictive value for poor myocardial perfusion in patients with a- cute myocardial infarction undergoing percutaneous coronary intervention,which is worth extending in clinic.

  8. The Average Widths and Non-linear Widths of the Classes of Multivariate Functions with Bounded Moduli of Smoothness

    Institute of Scientific and Technical Information of China (English)

    Yong-ping Liu; Gui-qiao Xu

    2002-01-01

    The classes of the multivariate functions with bounded moduli on Rd and Td are given and their average a-widths and non-linear n-widths are discussed. The weak asymptotic behaviors are established for the corresponding quantities.

  9. A recently developed bifacial platelet-rich fibrin matrix.

    Science.gov (United States)

    Lucarelli, E; Beretta, R; Dozza, B; Tazzari, P L; O'Connel, S M; Ricci, F; Pierini, M; Squarzoni, S; Pagliaro, P P; Oprita, E I; Donati, D

    2010-07-01

    Platelet-rich plasma (PRP) is used clinically in liquid or gel form to promote tissue repair. Because of the poor mechanical properties, conventional PRP is often difficult to handle when used in clinical settings and requires secure implantation in a specific site, otherwise when released growth factors could be washed out during an operation. In this study, we analyzed the end product of a recently developed commercially available system (FIBRINET), which is a dense pliable, platelet-rich fibrin matrix (PRFM). We characterized the mechanical properties of PRFM and tested whether PRFM releases growth factors and whether released factors induce the proliferation of mesenchymal stem cells (MSC). Mechanical properties as well as platelet distribution were evaluated in PRFM. PRFM demonstrated robust mechanical properties, with a tear elastic modulus of 937.3 +/- 314.6 kPa, stress at a break of 1476.0 +/- 526.3 kPa, and an elongation at break of 146.3 +/- 33.8 %. PRFM maintained its mechanical properties throughout the testing process. Microscopic observations showed that the platelets were localized on one side of the matrix. Elevated levels of PDGF-AA, PDGF-AB, EGF, VEGF, bFGF and TGF-beta1 were measured in the day 1-conditioned media (CM) of PRFM and growth factor levels decreased thereafter. BMP2 and BMP7 were not detectable. MSC culture media supplemented with 20% PRFM-CM stimulated MSC cell proliferation; at 24 and 48 hours the induction of the proliferation was significantly greater than the induction obtained with media supplemented with 20% foetal bovine serum. The present study shows that the production of a dense, physically robust PRFM made through high-speed centrifugation of intact platelets and fibrin in the absence of exogenous thrombin yields a potential tool for accelerating tissue repair.

  10. A recently developed bifacial platelet-rich fibrin matrix

    Directory of Open Access Journals (Sweden)

    E Lucarelli

    2010-07-01

    Full Text Available Platelet-rich plasma (PRP is used clinically in liquid or gel form to promote tissue repair. Because of the poor mechanical properties, conventional PRP is often difficult to handle when used in clinical settings and requires secure implantation in a specific site, otherwise when released growth factors could be washed out during an operation. In this study, we analyzed the end product of a recently developed commercially available system (FIBRINET®, which is a dense pliable, platelet-rich fibrin matrix (PRFM. We characterized the mechanical properties of PRFM and tested whether PRFM releases growth factors and whether released factors induce the proliferation of mesenchymal stem cells (MSC. Mechanical properties as well as platelet distribution were evaluated in PRFM. PRFM demonstrated robust mechanical properties, with a tear elastic modulus of 937.3 + 314.6 kPa, stress at a break of 1476.0 + 526.3 kPa, and an elongation at break of 146.3 + 33.8 %. PRFM maintained its mechanical properties throughout the testing process. Microscopic observations showed that the platelets were localized on one side of the matrix. Elevated levels of PDGF-AA, PDGF-AB, EGF, VEGF, bFGF and TGF-β1 were measured in the day 1-conditioned media (CM of PRFM and growth factor levels decreased thereafter. BMP2 and BMP7 were not detectable. MSC culture media supplemented with 20% PRFM-CM stimulated MSC cell proliferation; at 24 and 48 hours the induction of the proliferation was significantly greater than the induction obtained with media supplemented with 20% foetal bovine serum. The present study shows that the production of a dense, physically robust PRFM made through high-speed centrifugation of intact platelets and fibrin in the absence of exogenous thrombin yields a potential tool for accelerating tissue repair.

  11. Morphological evaluation of canine platelets on Giemsa- and PAS-stained blood smears.

    Science.gov (United States)

    Halmay, Dóra; Sótonyi, P; Vajdovich, P; Gaál, T

    2005-01-01

    The morphology of canine platelets (changes in size, shape, staining characteristics, degree of activation and clump formation, distribution of granules, appearance of vacuoles on Giemsa-stained smears) was investigated in 20 healthy control and 181 diseased dogs. In the group of the sick dogs 84 animals suffered from disorders affecting directly the haematological parameters or the haematopoietic organs such as bleeding, thymic haemorrhage, haemolytic disorders, lymphoma, immune-mediated thrombocytopenia, and other 97 dogs were affected by other diseases (hepatopathy, nephropathy, hepatic, splenic or intestinal neoplasm, skin diseases, diabetes mellitus, Cushing's syndrome, sepsis). The alterations found in platelet morphology were not specific for any disorder. The most common platelet abnormalities were polychromasia and the presence of giant platelets. These changes occurred in a high number in disorders accompanied by bleeding or haemolysis. Anisocytosis was the most frequent finding in hepatic, splenic or intestinal neoplasms and in certain endocrinopathies. Microcytosis was observed in immune-mediated thrombocytopenia, hepatic neoplasms and endocrine disorders. Extreme platelet activation was common in haemolysis, hepatopathies, neoplastic diseases and sepsis. Vacuolisation was present in thymic haemorrhage, pancreatitis, diabetes mellitus and Cushing's syndrome. A new morphologic phenomenon, i.e. a ring-like formation of granules, was described in the cytoplasm of the platelets both in healthy and diseased animals. In addition, two forms of pathologic granulation were also described for the first time in Giemsa-stained blood smears: the pseudonuclear and the spot-like formation of granules, which were observed especially in disorders affecting the blood cells. The granulation and morphological characteristics of platelets on smears stained by periodic acid-Schiff reaction (PAS) were also studied. Three localisations of granulation were observed, such as

  12. STABILIZATION OF STANDARD PLATELET CONCENTRATES AND MINIMIZATION OF THE PLATELET STORAGE LESION BY A PROSTACYCLIN ANALOG

    NARCIS (Netherlands)

    ELIAS, M; HEETHUIS, A; BOM, [No Value; BLOM, N; MCSHINE, RL; HALIE, MR; SIBINGA, CTS

    Platelet concentrates were pretreated with a stable synthetic prostacyclin analogue (Iloprost) at two different concentrations before the second centrifugation step (pelleting step) of preparation. This resulted in loss. of platelet sensitivity to aggregating agents. To mimic the situation after

  13. Mean platelet volume in acute rheumatic fever.

    Science.gov (United States)

    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.

  14. Therapeutic platelet reduction: Use in postsplenectomy thrombocytosis

    Directory of Open Access Journals (Sweden)

    Gita Negi

    2015-01-01

    Full Text Available 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.

  15. Laboratory testing for platelet function disorders.

    Science.gov (United States)

    Israels, S J

    2015-05-01

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

  16. SOL Width Scaling in the MAST Tokamak

    Science.gov (United States)

    Ahn, Joon-Wook; Counsell, Glenn; Connor, Jack; Kirk, Andrew

    2002-11-01

    Target heat loads are determined in large part by the upstream SOL heat flux width, Δ_h. Considerable effort has been made in the past to develop analytical and empirical scalings for Δh to allow reliable estimates to be made for the next-step device. The development of scalings for a large spherical tokamak (ST) such as MAST is particularly important both for development of the ST concept and for improving the robustness of scalings derived for conventional tokamaks. A first such scaling has been developed in MAST DND plasmas. The scaling was developed by flux-mapping data from the target Langmuir probe arrays to the mid-plane and fitting to key upstream parameters such as P_SOL, bar ne and q_95. In order to minimise the effects of co-linearity, dedicated campaigns were undertaken to explore the widest possible range of each parameter while keeping the remainder as fixed as possible. Initial results indicate a weak inverse dependence on P_SOL and approximately linear dependence on bar n_e. Scalings derived from consideration of theoretical edge transport models and integration with data from conventional devices is under way. The established scaling laws could be used for the extrapolations to the future machine such as Spherical Tokamak Power Plant (STPP). This work is jointly funded by Euratom and UK Department of Trade and Industry. J-W. Ahn would like to recognise the support of a grant from the British Foreign & Commonwealth Office.

  17. Differential effects of platelets and platelet inhibition by ticagrelor on TLR2- and TLR4-mediated inflammatory responses

    NARCIS (Netherlands)

    Tunjungputri, R.N.; Ven, A.J.A.M. van der; Riksen, N.P.; Rongen, G.A.P.J.M.; Tacke, S.; Berg, T.N.A. van den; Fijnheer, R.; Gomes, M.E.; Dinarello, C.A.; Veerdonk, F.L. van de; Gasem, M.H.; Netea, M.G.; Joosten, L.A.B.; Groot, P.G. de; Mast, Q. de

    2015-01-01

    Platelets and platelet-monocyte interaction play an important role in inflammation. Both pro- and anti-inflammatory effects of platelet inhibition have been reported in animal models. This study aimed to investigate the effect of platelets and platelet inhibition by the new P2Y12 receptor antagonist

  18. Chloride channels of platelets%血小板氯通道

    Institute of Scientific and Technical Information of China (English)

    陈晓琳; 尹松梅

    2004-01-01

    Chloride channels distribute widely in the body, and participate in many physiological actions and regulatory processes. Based on their physiological roles and molecular structures, six kinds of chloride channels have been identified: (1) The chloride channels family; (2) Cystic fibrosis transmembrane conductance regulator; (3) Swelling-activated chloride channels; (4) Calcium-activated chloride channels; (5) The p64 (CLIC) gene family; (6) γ-aminobutyric acid and glycine receptors. The chloride channels do exist in platelets, and their appearances are dependent on the presence of intracellular calcium. Blocking agents of chloride channels inhibit the thrombin-activated platelet aggregation and the elevation of the intracellular calcium concentration in a dose-dependent manner. It is suggested that chloride channels play a role in the activation of platelets. In addition, chloride channels act on both the cell volume regulation and the intracellular pH regulation in platelets.

  19. LDL oxidation by platelets propagates platelet activation via an oxidative stress-mediated mechanism.

    Science.gov (United States)

    Carnevale, Roberto; Bartimoccia, Simona; Nocella, Cristina; Di Santo, Serena; Loffredo, Lorenzo; Illuminati, Giulio; Lombardi, Elisabetta; Boz, Valentina; Del Ben, Maria; De Marco, Luigi; Pignatelli, Pasquale; Violi, Francesco

    2014-11-01

    Platelets generate oxidized LDL (ox-LDL) via NOX2-derived oxidative stress. We investigated if once generated by activated platelets ox-LDL can propagate platelet activation. Experiments were performed in platelets from healthy subjects (HS), hyper-cholesterolemic patients and patients with NOX2 hereditary deficiency. Agonist-stimulated platelets from HS added with LDL were associated with a dose-dependent increase of reactive oxidant species and ox-LDL. Agonist-stimulated platelets from HS added with a fixed dose of LDL (57.14 μmol/L) or added with homogenized human atherosclerotic plaque showed enhanced ox-LDL formation (approximately +50% and +30% respectively), which was lowered by a NOX2 inhibitor (approximately -35% and -25% respectively). Compared to HS, ox-LDL production was more pronounced in agonist-stimulated platelet rich plasma (PRP) from hyper-cholesterolemic patients but was almost absent in PRP from NOX2-deficient patients. Platelet aggregation and 8-iso-PGF2α-ΙΙΙ formation increased in LDL-treated washed platelets (+42% and +53% respectively) and PRP (+31% and +53% respectively). Also, LDL enhanced platelet-dependent thrombosis at arterial shear rate (+33%) but did not affect platelet activation in NOX2-deficient patients. Platelet activation by LDL was significantly inhibited by CD36 or LOX1 blocking peptides, two ox-LDL receptor antagonists, or by a NOX2 inhibitor. LDL-added platelets showed increased p38MAPK (+59%) and PKC (+51%) phosphorylation, p47(phox) translocation to platelet membrane (+34%) and NOX2 activation (+30%), which were inhibited by ox-LDL receptor antagonists. Platelets oxidize LDL, which in turn amplify platelet activation via specific ox-LDL receptors; both effects are mediated by NOX2 activation. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  20. GAP WIDTH STUDY IN LASER BUTT-WELDING

    DEFF Research Database (Denmark)

    Gong, Hui; Olsen, Flemming Ove

    In this paper the maximum allowable gap width in laser butt-welding is intensively studied. The gap width study (GWS) is performed on the material of SST of W1.4401 (AISI 316) under various welding conditions, which are the gap width : 0.00-0.50 mm, the welding speed : 0.5-2.0 m/min, the laser...... to the welding speed, (2) the larger laser power leads to the bigger maximum allowable gap width and (3) the focal point position has very little influence on the maximum gap width....... power : 2 and 2.6 kW and the focal point position : 0 and -1.2 mm. Quality of all the butt welds are destructively tested according to ISO 13919-1.Influences of the variable process parameters to the maximum allowable gap width are observed as (1) the maximum gap width is inversely related...

  1. Modeling and analysis of the HPM pulse-width upset effect on CMOS inverter

    Science.gov (United States)

    Xinhai, Yu; Changchun, Chai; Liping, Qiao; Yintang, Yang; Yang, Liu; Xiaowen, Xi

    2015-05-01

    We derive analytical models of the excess carrier density distribution and the HPM (high-power microwave) upset susceptibility with dependence of pulse-width, which are validated by the simulated results and experimental data. Mechanism analysis and model derivation verify that the excess carriers dominate the current amplification process of the latch-up. Our results reveal that the excess carrier density distribution in P-substrate behaves as pulse-width dependence. The HPM upset voltage threshold Vp decreases with the incremental pulse-width, while there is an inflection point which is caused because the excess carrier accumulation in the P-substrate will be suppressed over time. For the first time, the physical essence of the HPM pulse-width upset effect is proposed to be the excess carrier accumulation effect. Validation concludes that the Vp model is capable of giving a reliable and accurate prediction to the HPM upset susceptibility of a CMOS inverter, which simultaneously considers technology information, ambient temperature, and layout parameters. From the model, the layout parameter LB has been demonstrated to have a significant impact on the pulse-width upset effect: a CMOS inverter with minor LB is more susceptible to HPM, which enables us to put forward hardening measures for inverters that are immune from the HPM upset. Project supported by the National Natural Science Foundation of China (No. 60776034) and the State Key Development Program for Basic Research of China (No. 2014CB339900).

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

    Science.gov (United States)

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

    2012-01-01

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

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

    Directory of Open Access Journals (Sweden)

    Maria José Dantas Coêlho

    2011-01-01

    Full Text Available BACKGROUND: The study of platelet aggregation is essential to assess in vitro platelet function by different platelet activation pathways. OBJECTIVE: To assess aggregation and biochemical parameters of random platelet concentrates produced at the Fundação HEMOAM using the quality control tests defined by law. METHODS: Whole blood samples from 80 donors and the respective platelet concentrate units were tested. Platelet concentrates were tested (platelet count, aggregation and pH on days 1, 3 and 5 of storage. Additionally a leukocyte count was done only on day 1 and microbiological tests on day 5 of storage. Collagen and adenosine diphosphate were used as inducing agonists for platelet aggregation testing. RESULTS: Donor whole blood had normal aggregation (aggregation with adenosine diphosphate = 67% and with collagen = 78%. The median aggregation in platelet concentrates with adenosine diphosphate was low throughout storage (18% on day 1, 7% on day 3 and 6% on day 5 and the median aggregation with collagen was normal only on day 1 and low thereafter (54.4% on day 1, 20.5% on day 3 and 9% on day 5. CONCLUSION: Although the results were within the norms required by law, platelet concentrates had low aggregation rates. We suggest the inclusion of a functional assessment test for the quality control of platelet concentrates for a more effective response to platelet replacement therapy.

  4. Ultrastructural studies of the gray platelet syndrome.

    Science.gov (United States)

    White, J G

    1979-05-01

    The gray platelet syndrome (GPS) is a rare inherited disorder in which peripheral blood platelets are relatively large, vacuolated, and almost devoid of cytoplasmic granulation. In the present study we have evaluated the ultrastructure and cytochemistry of platelets from 2 patients with the GPS to determine precisely which organelles are missing from their cells. The findings indicate that gray platelets contain normal numbers of mitochondria, dense bodies, peroxisomes, and lysosomes but specifically lack alpha-granules. Preliminary studies of megakaryocytes from 1 of the 2 patients suggest that the defect in granule formation may lie at the level of the Golgi zone.

  5. Identification of platelet refractoriness in oncohematologic patients

    Directory of Open Access Journals (Sweden)

    Aline Aparecida Ferreira

    2011-01-01

    Full Text Available 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.

  6. Does bipolar pacemaker current activate blood platelets?

    DEFF Research Database (Denmark)

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

    2009-01-01

    OBJECTIVE: The aim of this study was to investigate whether bipolar pacemaker current lead can activate blood platelets. The null hypothesis was that 1 minute of electrical stimulation of platelets would not influence their subsequent reactivity to adenosine diphosphate (ADP). BACKGROUND: Both...... platelets and muscle cells contain actin and myosin filaments, and both cells are activated following calcium influx. Muscle cells open their calcium channels and contract when exposed to an electric current. Current through a bipolar pacemaker lead will expose a small volume of blood, including platelets...

  7. Platelet cytoskeleton and its hemostatic role.

    Science.gov (United States)

    Cerecedo, Doris

    2013-12-01

    Upon vascular injury, platelets adhere to the exposed extracellular matrix, which triggers the platelet activation and aggregation to form a hemostatic plug to seal the wound. All of these events involve dramatic changes in shape because of the cytoskeleton reorganization. The versatility of the cytoskeleton's main elements depends on the biochemical nature of the elements, as well as on the associated proteins that confer multiple functions within the cell. The list of these associated proteins grows actively, increasing our knowledge concerning the complexity of platelet cytoskeleton machinery. The present review evidences the recently described platelet proteins that promote characteristic modifications in their cytoskeleton organization, with special focus on the dystrophin-glycoprotein complex.

  8. Platelet function alterations in dengue are associated with plasma leakage

    NARCIS (Netherlands)

    Michels, M.; Alisjahbana, B.; Groot, P.G. de; Indrati, A.R.; Fijnheer, R.; Puspita, M.; Dewi, I.M.; Wijer, L. van de; Boer, E.M. de; Roest, M.; Ven, A.J. van der; Mast, Q. de

    2014-01-01

    Severe dengue is characterised by thrombocytopenia, plasma leakage and bleeding. Platelets are important for preservation of endothelial integrity. We hypothesised that platelet activation with secondary platelet dysfunction contribute to plasma leakage. In adult Indonesian patients with acute dengu

  9. Kinetics and sites of destruction of /sup 111/In-oxine-labeled platelets in idiopathic thrombocytopenic purpura: a quantitative study

    Energy Technology Data Exchange (ETDEWEB)

    Heyns, A.D.; Loetter, M.G.; Badenhorst, P.N.; de Kock, F.; Pieters, H.; Herbst, C.; van Reenen, O.R.; Kotze, H.; Minnaar, P.C.

    1982-04-01

    Kinetics and quantification of the sites of destruction of /sup 111/In-oxine-labeled autologous platelets were investigated in eight patients with idiopathic thrombocytopenic purpura. The mean platelet count was 17 +/- 9 X 10(9)/liter; platelets were separated by differential centrifugation and labeled with 5.6 +/- 2.5 MBq /sup 111/In. Whole body and organ /sup 111/In-platelet distribution was quantitated with a scintillation camera and a computer-assisted imaging system acquisition matrix. Areas of interest were selected with the computer and organ /sup 111/In-radioactivity expressed as a percentage of whole body activity. Mean platelet survival was 49.5 +/- 29.6 hr and the survival curves were exponential. Equilibrium percentage organ /sup 111/In-radioactivity was (normal values in parentheses): spleen 33.7 +/- 8.8 (31.1 +/- 10.2); liver 16.1 +/- 9.5 (13.1 +/- 1.3); thorax 22.8 +/- 3.7 (28.2 +/- 5.6). Percentage organ /sup 111/In-activity at the time when labeled platelets had disappeared from the circulation was: spleen 44.5 +/- 16.4 (40 +/- 16); liver 16.0 +/- 11.5 (32.4 +/- 7.2); thorax 19.7 +/- 6.0 (17.7 +/- 10.3). Thorax activity corresponds to bone marrow radioactivity. Three patterns of platelet sequestration were evident. Three patients had mainly splenic sequestration, two mainly hepatic sequestration, and three diffuse reticuloendothelial system sequestration with a major component of platelets destroyed in the bone marrow. Splenectomy was performed in two patients. The pattern of /sup 111/In-platelet sequestration was not predictive of response of glucocorticoid therapy or indicative of the necessity for splenectomy. Quantitative /sup 111/In-labeled autologous platelet kinetic studies provide a new tool for the investigation of platelet disorders.U

  10. The effects of Lonomin V, a toxin from the caterpillar (Lonomia achelous), on hemostasis parameters as measured by platelet function.

    Science.gov (United States)

    Guerrero, Belsy; Arocha-Piñango, Carmen L; Salazar, Ana M; Gil, Amparo; Sánchez, Elda E; Rodríguez-Acosta, Alexis; Lucena, Sara

    2011-09-15

    Platelets play a central role in hemostasis during vascular injury. Patients affected with the hemorrhagic syndrome caused by contact with Lonomia achelous caterpillars (Lac) Lepidoptera distributed in various South American countries, show digestive, pulmonary and intraperitoneal bleeding in combination with hematomas and echymosis. In the present study, we have evaluated the effects of Lonomin V (serine protease isolated from Lac hemolymph) on some functional properties of platelets, evaluating its importance in primary hemostasis. Platelet adhesion to fibrinogen was reduced by 19, 20, 36, and 37% after pre-treated with 0.2, 2, 20 and 40 nM of Lonomin V, respectively. Pre-incubation of the platelets with 408 nM of Lonomin V, for 4 min at 37 °C, resulted in complete inhibition of the collagen-induced platelet aggregation, in contrast to 56% inhibition of the ADP - induced platelet aggregation. Lonomin V also inhibited anti-α(IIb)β(3) integrin binding to platelets by 56, 57, 52 and 54% at concentrations of 0.2, 2, 20 and 40 nM respectively. Additionally, Lonomin V inhibited anti-P-selectin binding to platelets by 28, 37, 33 and 33% at the same concentrations. The platelets tested with Lonomin V did not modify their viability. In summary, Lonomin V inhibited platelet aggregation, probably caused by the degradation of collagen. The anti-platelet activity of Lonomin V has been shown to be unique and a potentially useful tool for investigating cell-matrix and cell-cell interactions and for the development of antithrombotic agents in terms of their anti-adhesive activities.

  11. STELLAR LOCI. I. METALLICITY DEPENDENCE AND INTRINSIC WIDTHS

    Energy Technology Data Exchange (ETDEWEB)

    Yuan, Haibo; Liu, Xiaowei [Kavli Institute for Astronomy and Astrophysics, Peking University, Beijing 100871 (China); Xiang, Maosheng; Huang, Yang; Chen, Bingqiu, E-mail: yuanhb4861@pku.edu.cn, E-mail: x.liu@pku.edu.cn [Department of Astronomy, Peking University, Beijing 100871 (China)

    2015-02-01

    Stellar loci are widely used for selection of interesting outliers, reddening determinations, and calibrations. However, until now, the dependence of stellar loci on metallicity has not been fully explored, and their intrinsic widths are unclear. In this paper, by combining the spectroscopic and recalibrated imaging data of the Sloan Digital Sky Survey (SDSS) Stripe 82, we have built a large, clean sample of dwarf stars with accurate colors and well-determined metallicities to investigate the metallicity dependence and intrinsic widths of the SDSS stellar loci. Typically, 1 dex decrease in metallicity causes 0.20 and 0.02 mag decrease in colors u – g and g – r and 0.02 and 0.02 mag increase in colors r – i and i – z, respectively. The variations are larger for metal-rich stars than for metal-poor ones, and larger for F/G/K stars than for A/M ones. Using the sample, we have performed two-dimensional polynomial fitting to the u – g, g – r, r – i, and i – z colors as a function of color g – i and metallicity [Fe/H]. The residuals, at the level of 0.029, 0.008, 0.008, and 0.011 mag for the u – g, g – r, r – i, and i – z colors, respectively, can be fully accounted for by the photometric errors and metallicity uncertainties, suggesting that the intrinsic widths of the loci are at maximum a few millimagnitudes. The residual distributions are asymmetric, revealing that a significant fraction of stars are binaries. In a companion paper, we will present an unbiased estimate of the binary fraction for field stars. Other potential applications of the metallicity-dependent stellar loci are briefly discussed.

  12. Platelet-rich plasma preparation using three devices : Implications for platelet activation and platelet growth factor release

    NARCIS (Netherlands)

    Everts, Peter A. M.; Mahoney, Christine Brown; Hoffmann, Johannes J. M. L.; Schonberger, Jacques P. A. M.; Box, Henk A. M.; Van Zundert, Andre; Knape, Johannes T. A.

    2006-01-01

    Background: In this study, three commercial systems for the preparation of platelet-rich plasma (PRP) were compared and platelet growth factors release was measured. Methods: Ten healthy volunteers donated whole blood that was fractionated by a blood cell separator, and a table-top centrifuge to pre

  13. Hereditary sideroblastic anemia with associated platelet abnormalities.

    Science.gov (United States)

    Soslau, G; Brodsky, I

    1989-12-01

    A 62 year old male (R.H.) presented with a mild anemia (Hb 11-12 gm%) and a history of multiple hemorrhagic episodes. The marrow had 40-50% sideroblasts. Marrow chromosomes were normal. His wife was hematologically normal, while one daughter, age 30 years, had a sideroblastic anemia (Hb 11-12 gm%) with 40-50% sideroblasts in the marrow. Her anemia was first noted at age 15 years. Administration of vitamin B6 did not correct the anemia in either the father or daughter. Platelet abnormalities inherited jointly with this disorder are described for the first time. Both R.H. and his daughter had prolonged bleeding times, with normal PTT, PT times, fVIII:C, fVIII:Ag levels, and vWF multimers, which may rule out a von Willebrand's disease. They have normal platelet numbers but abnormally low platelet adhesiveness and greatly depressed ADP, collagen, and epinephrine responsiveness. Response to ristocetin was in the low normal range, and aggregation with thrombin was normal. While desmopressin completely normalized R.H.'s bleeding time, none of these platelet parameters were improved. No differences in the SDS PAGE protein patterns of RH platelets could be detected in comparison to normal samples. His platelets took up and released serotonin (5HT) normally, and electron micrographs defined no morphological abnormalities. However, no ATP was released from platelets activated with collagen, and when followed by thrombin about fourfold greater ATP was released by control platelets as compared to RH platelets. The dense granule fraction derived from RH platelets contained about 20% the level of ATP, 40% the level of ADP, and 50% the level of 5HT detected in a normal sample. The results indicate that the bleeding disorder is related to a non-classical heritable storage pool defect. The connection between the inherited sideroblastic anemia and platelet defects is obscure.

  14. Multiple alterations of platelet functions dominated by increased secretion in mice lacking Cdc42 in platelets

    DEFF Research Database (Denmark)

    Pleines, Irina; Eckly, Anita; Elvers, Margitta;

    2010-01-01

    formation and exocytosis in various cell types, but its exact function in platelets is not established. Here, we show that the megakaryocyte/platelet-specific loss of Cdc42 leads to mild thrombocytopenia and a small increase in platelet size in mice. Unexpectedly, Cdc42-deficient platelets were able to form...... reduced, suggesting increased clearing of the cells under physiologic conditions. These data point to novel multiple functions of Cdc42 in the regulation of platelet activation, granule organization, degranulation, and a specific role in GPIb signaling....

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

    Directory of Open Access Journals (Sweden)

    Sunitha Raja V

    2008-01-01

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

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

    Science.gov (United States)

    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 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 HELLP syndrome.

  17. Human platelets antigens influence the viral load of platelets after the interaction of the platelets with HCV and HIV in vitro

    Directory of Open Access Journals (Sweden)

    Rejane Maria Tommasini Grotto

    Full Text Available Abstract: INTRODUCTION: In this study, we evaluated hepatitis C virus (HCV and human immunodeficiency virus (HIV - platelet interactions in vitro as well as human platelets antigen (HPA polymorphisms. METHODS: Platelets were obtained from 100 healthy HPA-genotyped volunteer donors and incubated with HIV or HCV. The viral load after in vitro exposure was detected. RESULTS: The viral load in the platelets after exposure to the virus was higher in the HIV exposure than in the HCV exposure. CONCLUSIONS: HIV-platelet ligation could be more efficient than HCV-platelet interaction. Further, the HPA-1b allele seems to influence the interaction of platelets with HCV.

  18. Visual-Width of an Ultrasonic Gaussian Beam on the Schlieren Photograph and Explanation to the Nonspecularly Reflected Sound Field

    Institute of Scientific and Technical Information of China (English)

    ZHU Guo-Zhen; SUN Yao; FU De-Yong

    2004-01-01

    @@ On the Schlieren photograph, a continuous ultrasonic Gaussian beam and its nonspecularly reflected beams [Chin.Phys. Lett. 16 (1999) 819] always have limited visual-width, although the theoretical spatial distribution of the sound field is a continuous function. To study this problem, the first step is to investigate the visual-width of the beam on the photograph related to the sound pressure at the centre of the beam by the threshold of the optical system caused by the refraction of light; the second step is to explain the visual-width of nonspecularly reflected field. By applying a relevant threshold, checked by the visual width of the incident beam, to cut the theoretical curves of the reflected sound field, one can find the visual-width of the two reflected beams and the gap between them correspond to that on the Schlieren photograph.

  19. Correlation of red blood cell distribution width and ventricular tachycardia,ventricular flutter/entricular fibrillation in hospitalized patients with chronic heart failure%慢性心力衰竭患者红细胞分布宽度与室性心动过速、心室扑动/心室颤动的相关性分析

    Institute of Scientific and Technical Information of China (English)

    朱春海; 倪晓媚; 卢益中

    2015-01-01

    目的 探讨慢性心力衰竭患者红细胞分布宽度(RDW)与室性心动过速、心室扑动/心室颤动发生的关系.方法 将96例慢性心力衰竭患者按照入院时RDW四分位分组,比较各组患者相关心功能指标、实验室检查指标,住院期间是否发生室性心动过速、心室扑动/心室颤动,用Iogistic回归方程分析RDW与慢性心力衰竭患者发生室性心动过速、心室扑动/心室颤动的关系.结果 RDW四分位分组中,从Ⅰ组到Ⅳ组,患者NT- proBNP逐渐增高(P<0.05),Ⅳ组中发生室性心动过速、心室扑动/心室颤动患者的比例(75.0%)高于Ⅲ组(41.6%)(P<0.05),Ⅲ组高于Ⅰ组(4.2%)及Ⅱ组(8.3%)(P<0.05);多因素logistic回归分析显示:RDW是室性心动过速、心室扑动/心室颤动发生的高危因素(OR=1.749,P<0.05).结论 高RDW水平与慢性心力衰竭患者室性心动过速、心室扑动/心室颤动的发生相关.%Objective To investigate the correlation of red blood cell distribution width (RDW) and ventricular tachycardia,ventricular flutter/ventricular fibrillation in hospitalized patients with chronic heart failure (CHF)).Methods 136 cases of CHF patients were divided into four groups according to quartile of RDW.Heart function,laboratory data,ventricular tachycardia and ventricular flutter/ventricular fibrillation during hospitalization were compared between groups.The relation between RDW and malignant ventricular arrhythmias was analyzed by multiple logistic regression.Results From quartile 1 to quartile 4,NT- proBNP increased gradually (P<0.05).The incidence of ventricular tachycardia and ventricular flutter/ventricular fibrillation was significantly higher in quartile 4 than quartile 3 (75.0% vs.41.6%,P<0.05),significantly higher in quartile 3 than in quartile 1 (8.3%) and quartile 2 (4.2%)(all P<0.05).Multivariable Logistic regression analysis showed that RDW was a risk factor for ventricular tachycardia and ventricular flutter

  20. Expansion of the neonatal platelet mass is achieved via an extension of platelet lifespan.

    Science.gov (United States)

    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.

  1. [Platelet allo-antibodies identification strategies for preventing and managing platelet refractoriness].

    Science.gov (United States)

    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.

  2. Platelet antibodies, activated platelets and serum leptin in childhood immune thrombocytopenic purpura.

    Science.gov (United States)

    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.

  3. Bulk fluid phase behaviour of colloidal platelet-sphere and platelet-polymer mixtures.

    Science.gov (United States)

    de las Heras, Daniel; Schmidt, Matthias

    2013-04-13

    Using a geometry-based fundamental measure density functional theory, we calculate bulk fluid phase diagrams of colloidal mixtures of vanishingly thin hard circular platelets and hard spheres. We find isotropic-nematic phase separation, with strong broadening of the biphasic region, upon increasing the pressure. In mixtures with large size ratio of platelet and sphere diameters, there is also demixing between two nematic phases with differing platelet concentrations. We formulate a fundamental measure density functional for mixtures of colloidal platelets and freely overlapping spheres, which represent ideal polymers, and use it to obtain phase diagrams. We find that, for low platelet-polymer size ratio, in addition to isotropic-nematic and nematic-nematic phase coexistence, platelet-polymer mixtures also display isotropic-isotropic demixing. By contrast, we do not find isotropic-isotropic demixing in hard-core platelet-sphere mixtures for the size ratios considered.

  4. IgG platelet antibodies in EDTA-dependent pseudothrombocytopenia bind to platelet membrane glycoprotein IIb.

    Science.gov (United States)

    Fiorin, F; Steffan, A; Pradella, P; Bizzaro, N; Potenza, R; De Angelis, V

    1998-08-01

    EDTA-dependent pseudothrombocytopenia (PTCP) consists of an inappropriate low platelet count caused by autoantibodies present in the serum samples reacting with platelets only in EDTA-anticoagulated blood. By using immunoprecipitation and Western blot techniques, we studied the immunochemical specificity of platelet agglutinating autoantibodies in the serum samples of 10 patients with PTCP. Furthermore, to evaluate a possible role of PTCP-associated IgG autoantibodies in increased platelet turnover, we assayed the plasma glycocalicin (GC) level and calculated the GC index for every patient. Our results provide direct evidence that an epitope located on platelet membrane glycoprotein IIb is recognized by PTCP-associated IgG antibodies; moreover GC levels in patients with EDTA-dependent PTCP were similar to control levels, thus excluding an increased platelet turnover. We conclude that antiplatelet antibodies directed against platelet cryptantigens are unlikely to have a major role in the increased removal of cells from circulation.

  5. Half-width at half-maximum, full-width at half-maximum analysis for resolution of asymmetrically apodized optical systems with slit apertures

    Indian Academy of Sciences (India)

    Andra Naresh Kumar Reddy; Dasari Karuna Sagar

    2015-01-01

    Resolution for the modified point spread function (PSF) of asymmetrically apodized optical systems has been analysed by a new parameter half-width at half-maximum (HWHM) in addition to the well-defined parameter full-width at half-maximum (FWHM). The distribution of half-maximum energy in the centroid of modified PSF has been investigated in terms of HWHM on good side and HWHM on bad side. We observed that as the asymmetry in PSF increases, FWHM of the main peak increases and then decreases and is being aided by the degree of amplitude apodization in the central region of slit functions. In the present study, HWHM (half-width at half-maximum) of the resultant PSF has been defined to characterize the resolution of the detection system. It is essentially a line of projection, which measures the width of the main lobe at its half-maximum position from the diffraction centre and has been computed for various amplitudes and antiphase apodizations of the slit aperture. We have noticed that HWHM on the good side decreases at the cost of the increased HWHM on the bad side in the presence of asymmetric apodization.

  6. The significance of biometric parameters in determining anterior teeth width

    Directory of Open Access Journals (Sweden)

    Strajnić Ljiljana

    2013-01-01

    Full Text Available Background/Aim. An important element of prosthetic treatment of edentulous patients is selecting the size of anterior artificial teeth that will restore the natural harmony of one’s dentolabial structure as well as the whole face. The main objective of this study was to determine the correlation between the inner canthal distance (ICD and interalar width (IAW on one side and the width of both central incisors (CIW, the width of central and lateral incisors (CLIW, the width of anterior teeth (ATW, the width between the canine cusps (CCW, which may be useful in clinical practice. Methods. A total of 89 subjects comprising 23 male and 66 female were studied. Their age ranged from 19 to 34 years with the mean of 25 years. Only the subjects with the preserved natural dentition were included in the sample. All facial and intraoral tooth measurements were made with a Boley Gauge (Buffalo Dental Manufacturing Co., Brooklyn NY, USA having a resolution of 0.1mm. Results. A moderate correlation was established between the interalar width and combined width of anterior teeth and canine cusp width (r = 0.439, r = 0.374. A low correlation was established between the inner canthal distance and the width of anterior teeth and canine cusp width (r = 0.335, r = 0.303. The differences between the two genders were highly significant for all the parameters (p < 0.01. The measured facial distances and width of anterior teeth were higher in men than in women. Conclusion. The results of this study suggest that the examined interalar width and inner canthal distance cannot be considered reliable guidelines in the selection of artificial upper anterior teeth. However, they may be used as a useful additional factor combined with other methods for objective tooth selection. The final decision should be made while working on dentures fitting models with the patient’s consent.

  7. An investigation of bridge width measurement and processing capabilities (1985)

    Energy Technology Data Exchange (ETDEWEB)

    Armstrong, K.P. [comp.

    1989-05-15

    An investigation of Mound`s ability to measure and process bridges was conducted in 1985. Prior to improvements in the measuring system and technique, bridge width was found to have a sigma of 0.00019 in. After improvements were made, a sigma of 0.000047 was realized. Bridge length was found to be more erratic than width, although most of the inaccuracy was caused by measurement uncertainty. Length and width were found to have little or no correlation.

  8. Clinica use of platelet additive solutions.

    Science.gov (United States)

    van Rhenen, Dick J

    2007-12-01

    Randomised clinical trial (RCT) to study the clinical efficacy and safety of new platelet products using platelet additive solutions are scarce. In this paper a number of recent RCT's is discussed. It can be the start of a development where new transfusion products enter a RCT before the product is applied in clinical practice.

  9. Platelets in liver transplantation : Friend or foe?

    NARCIS (Netherlands)

    Pereboom, Ilona T. A.; Lisman, Ton; Porte, Robert J.

    2008-01-01

    Apart from the well-known role of blood platelets in hemostasis, there is emerging evidence that platelets have various nonhemostatic properties that play a critical role in inflammation, angiogenesis, tissue repair and regeneration, and ischemia/reperfusion (I/R) injury. All these processes may be

  10. Studies on megakaryopoiesis and platelet function

    NARCIS (Netherlands)

    Meinders, M.

    2015-01-01

    Platelets are blood circulating specialized subcellular fragments, which are produced by megakaryocytes. Platelets are essential for hemostasis and wound healing but also play a role in non-hemostatic processes such as the immune response or cancer metastasis. Considering the immediate precursors of

  11. Erythrocyte-platelet interaction in uncomplicated pregnancy.

    Science.gov (United States)

    Swanepoel, Albe C; Pretorius, Etheresia

    2014-12-01

    Maternal and fetal requirements during uncomplicated pregnancy are associated with changes in the hematopoietic system. Platelets and erythrocytes [red blood cells (RBCs)], and especially their membranes, are involved in coagulation, and their interactions may provide reasons for the changed hematopoietic system during uncomplicated pregnancy. We review literature regarding RBC and platelet membrane structure and interactions during hypercoagulability and hormonal changes. We then study interactions between RBCs and platelets in uncomplicated pregnancy, as their interactions may be one of the reasons for increased hypercoagulability during uncomplicated pregnancy. Scanning electron microscopy was used to study whole blood smears from 90 pregnant females in different phases of pregnancy. Pregnancy-specific interaction was seen between RBCs and platelets. Typically, one or more platelets interacted through platelet spreading and pseudopodia formation with a single RBC. However, multiple interactions with RBCs were also shown for a single platelet. Specific RBC-platelet interaction seen during uncomplicated pregnancy may be caused by increased estrogen and/or increased fibrinogen concentrations. This interaction may contribute to the hypercoagulable state associated with healthy and uncomplicated pregnancy and may also play a fundamental role in gestational thrombocytopenia.

  12. BETA-ADRENOBLOCKERS AND PLATELET AGGREGATION. CARVEDILOL

    Directory of Open Access Journals (Sweden)

    A. N. Zakirova

    2008-01-01

    Full Text Available Approaches evolution to studying of beta-blockers influence on platelet aggregation is reviewed. The current view on of beta-blocker antiplatelet effects is presented on the basis of physical and chemical drug properties (water repellency, dipole moment, molecular mass. Trail results on carvedilol influence on platelet aggregation are focused.

  13. Novel agents for anti-platelet therapy

    Directory of Open Access Journals (Sweden)

    Ji Xuebin

    2011-11-01

    Full Text Available Abstract Anti-platelet therapy plays an important role in the treatment of patients with thrombotic diseases. The most commonly used anti-platelet drugs, namely, aspirin, ticlopidine, and clopidogrel, are effective in the prevention and treatment of cardio-cerebrovascular diseases. Glycoprotein IIb/IIIa antagonists (e.g., abciximab, eptifibatide and tirofiban have demonstrated good clinical benefits and safety profiles in decreasing ischemic events in acute coronary syndrome. However, adverse events related to thrombosis or bleeding have been reported in cases of therapy with glycoprotein IIb/IIIa antagonists. Cilostazol is an anti-platelet agent used in the treatment of patients with peripheral ischemia, such as intermittent claudication. Presently, platelet adenosine diphosphate P2Y(12 receptor antagonists (e.g., clopidogrel, prasugrel, cangrelor, and ticagrelor are being used in clinical settings for their pronounced protective effects. The new protease-activated receptor antagonists, vorapaxar and atopaxar, potentially decrease the risk of ischemic events without significantly increasing the rate of bleeding. Some other new anti-platelet drugs undergoing clinical trials have also been introduced. Indeed, the number of new anti-platelet drugs is increasing. Consequently, the efficacy of these anti-platelet agents in actual patients warrants scrutiny, especially in terms of the hemorrhagic risks. Hopefully, new selective platelet inhibitors with high anti-thrombotic efficiencies and low hemorrhagic side effects can be developed.

  14. Performance evaluation of PL-11 platelet analyzer

    Institute of Scientific and Technical Information of China (English)

    张有涛

    2013-01-01

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

  15. Platelet affinity for burro aorta collagen

    Energy Technology Data Exchange (ETDEWEB)

    Schneider, M.D.

    1977-10-01

    Despite ingenious concepts, there are no unequivocal clues as to what, when, and how some undefined biochemical factor(s) or constituent(s) that localizes in the arterial wall can precipitate a thromboatheromatous lesion or arterial disease. The present study focused on the extraction, partial purification, and characterization of a collagen-active platelet stimulator from the aortas of aged burros. The aggregator moiety in the aorta extracts invariably had a higher affinity for platelets in citrated platelet-rich plasma of human beings than for platelets of homologous burros. The platelet-aggregating factor(s) in the aorta extract was retained by incubation with ..cap alpha..-chymotrypsin. Platelet-aggregating activity was rapidly abolished after incubation with collagenase, as determined by platelet-aggregometry tests. Evidence based on light microscope and polysaccharide histochemical reactions indicates a probability that the intracellular amorphous matrix (PAS-positive) and filamentous components (PTAH-positive) expelled from smooth muscle cells disrupted during homogenization of the aorta may be a principal source of a precursor collagen species which is a potent inducer of platelet aggregation.

  16. The origin and function of platelet glycosyltransferases

    DEFF Research Database (Denmark)

    Wandall, Hans H; Rumjantseva, Viktoria; Sørensen, Anne Louise Tølbøll;

    2012-01-01

    Platelets are megakaryocyte subfragments that participate in hemostatic and host defense reactions and deliver pro- and anti-angiogenic factors throughout the vascular system. Platelets are anucleated cells and lack a complex secretory apparatus with distinct Golgi/endoplasmic reticulum compartme...

  17. Measurement of magnetic domain wall width using energy-filtered Fresnel images.

    Science.gov (United States)

    Lloyd, S J; Loudon, J C; Midgley, P A

    2002-08-01

    Magnetic domain walls in Nd2Fe14B have been examined using a series of energy-filtered Fresnel images in the field emission gun transmission electron microscope (FEGTEM). We describe the changes in the intensity distribution of the convergent wall image as a function of defocus, foil thickness and domain wall width. The effect of tilted domain walls and beam convergence on the fringe pattern is also discussed. A comparison of the experimental intensity profile with that from simulations allows the domain wall width to be determined. Measurement of very narrow walls is made possible only by using a relatively thick foil, which necessitates energy-filtering to allow quantitative comparison with simulations. The magnetic domain wall width in Nd2Fe14B was found to be 3 +/- 2 nm.

  18. Direct measurement of the total decay width of the top quark.

    Science.gov (United States)

    Aaltonen, T; Amerio, S; Amidei, D; Anastassov, A; Annovi, A; Antos, J; Apollinari, G; Appel, J A; Arisawa, T; Artikov, A; Asaadi, J; Ashmanskas, W; Auerbach, B; Aurisano, A; Azfar, F; Badgett, W; Bae, T; Barbaro-Galtieri, A; Barnes, V E; Barnett, B A; Barria, P; Bartos, P; Bauce, M; Bedeschi, F; Behari, S; Bellettini, G; Bellinger, J; Benjamin, D; Beretvas, A; Bhatti, A; Bland, K R; Blumenfeld, B; Bocci, A; Bodek, A; Bortoletto, D; Boudreau, J; Boveia, A; Brigliadori, L; Bromberg, C; Brucken, E; Budagov, J; Budd, H S; Burkett, K; Busetto, G; Bussey, P; Butti, P; Buzatu, A; Calamba, A; Camarda, S; Campanelli, M; Canelli, F; Carls, B; Carlsmith, D; Carosi, R; Carrillo, S; Casal, B; Casarsa, M; Castro, A; Catastini, P; Cauz, D; Cavaliere, V; Cavalli-Sforza, M; Cerri, A; Cerrito, L; Chen, Y C; Chertok, M; Chiarelli, G; Chlachidze, G; Cho, K; Chokheli, D; Clark, A; Clarke, C; Convery, M E; Conway, J; Corbo, M; Cordelli, M; Cox, C A; Cox, D J; Cremonesi, M; Cruz, D; Cuevas, J; Culbertson, R; d'Ascenzo, N; Datta, M; de Barbaro, P; Demortier, L; Deninno, M; D'Errico, M; Devoto, F; Di Canto, A; Di Ruzza, B; Dittmann, J R; Donati, S; D'Onofrio, M; Dorigo, M; Driutti, A; Ebina, K; Edgar, R; Elagin, A; Erbacher, R; Errede, S; Esham, B; Farrington, S; Fernández Ramos, J P; Field, R; Flanagan, G; Forrest, R; Franklin, M; Freeman, J C; Frisch, H; Funakoshi, Y; Galloni, C; Garfinkel, A F; Garosi, P; Gerberich, H; Gerchtein, E; Giagu, S; Giakoumopoulou, V; Gibson, K; Ginsburg, C M; Giokaris, N; Giromini, P; Giurgiu, G; Glagolev, V; Glenzinski, D; Gold, M; Goldin, D; Golossanov, A; Gomez, G; Gomez-Ceballos, G; Goncharov, M; González López, O; Gorelov, I; Goshaw, A T; Goulianos, K; Gramellini, E; Grinstein, S; Grosso-Pilcher, C; Group, R C; Guimaraes da Costa, J; Hahn, S R; Han, J Y; Happacher, F; Hara, K; Hare, M; Harr, R F; Harrington-Taber, T; Hatakeyama, K; Hays, C; Heinrich, J; Herndon, M; Hocker, A; Hong, Z; Hopkins, W; Hou, S; Hughes, R E; Husemann, U; Hussein, M; Huston, J; Introzzi, G; Iori, M; Ivanov, A; James, E; Jang, D; Jayatilaka, B; Jeon, E J; Jindariani, S; Jones, M; Joo, K K; Jun, S Y; Junk, T R; Kambeitz, M; Kamon, T; Karchin, P E; Kasmi, A; Kato, Y; Ketchum, W; Keung, J; Kilminster, B; Kim, D H; Kim, H S; Kim, J E; Kim, M J; Kim, S H; Kim, S B; Kim, Y J; Kim, Y K; Kimura, N; Kirby, M; Knoepfel, K; Kondo, K; Kong, D J; Konigsberg, J; Kotwal, A V; Kreps, M; Kroll, J; Kruse, M; Kuhr, T; Kurata, M; Laasanen, A T; Lammel, S; Lancaster, M; Lannon, K; Latino, G; Lee, H S; Lee, J S; Leo, S; Leone, S; Lewis, J D; Limosani, A; Lipeles, E; Lister, A; Liu, H; Liu, Q; Liu, T; Lockwitz, S; Loginov, A; Lucchesi, D; Lucà, A; Lueck, J; Lujan, P; Lukens, P; Lungu, G; Lys, J; Lysak, R; Madrak, R; Maestro, P; Malik, S; Manca, G; Manousakis-Katsikakis, A; Marchese, L; Margaroli, F; Marino, P; Martínez, M; Matera, K; Mattson, M E; Mazzacane, A; Mazzanti, P; McNulty, R; Mehta, A; Mehtala, P; Mesropian, C; Miao, T; Mietlicki, D; Mitra, A; Miyake, H; Moed, S; Moggi, N; Moon, C S; Moore, R; Morello, M J; Mukherjee, A; Muller, Th; Murat, P; Mussini, M; Nachtman, J; Nagai, Y; Naganoma, J; Nakano, I; Napier, A; Nett, J; Neu, C; Nigmanov, T; Nodulman, L; Noh, S Y; Norniella, O; Oakes, L; Oh, S H; Oh, Y D; Oksuzian, I; Okusawa, T; Orava, R; Ortolan, L; Pagliarone, C; Palencia, E; Palni, P; Papadimitriou, V; Parker, W; Pauletta, G; Paulini, M; Paus, C; Phillips, T J; Piacentino, G; Pianori, E; Pilot, J; Pitts, K; Plager, C; Pondrom, L; Poprocki, S; Potamianos, K; Pranko, A; Prokoshin, F; Ptohos, F; Punzi, G; Ranjan, N; Redondo Fernández, I; Renton, P; Rescigno, M; Rimondi, F; Ristori, L; Robson, A; Rodriguez, T; Rolli, S; Ronzani, M; Roser, R; Rosner, J L; Ruffini, F; Ruiz, A; Russ, J; Rusu, V; Sakumoto, W K; Sakurai, Y; Santi, L; Sato, K; Saveliev, V; Savoy-Navarro, A; Schlabach, P; Schmidt, E E; Schwarz, T; Scodellaro, L; Scuri, F; Seidel, S; Seiya, Y; Semenov, A; Sforza, F; Shalhout, S Z; Shears, T; Shepard, P F; Shimojima, M; Shochet, M; Shreyber-Tecker, I; Simonenko, A; Sliwa, K; Smith, J R; Snider, F D; Song, H; Sorin, V; St Denis, R; Stancari, M; Stentz, D; Strologas, J; Sudo, Y; Sukhanov, A; Suslov, I; Takemasa, K; Takeuchi, Y; Tang, J; Tecchio, M; Teng, P K; Thom, J; Thomson, E; Thukral, V; Toback, D; Tokar, S; Tollefson, K; Tomura, T; Tonelli, D; Torre, S; Torretta, D; Totaro, P; Trovato, M; Ukegawa, F; Uozumi, S; Vázquez, F; Velev, G; Vellidis, C; Vernieri, C; Vidal, M; Vilar, R; Vizán, J; Vogel, M; Volpi, G; Wagner, P; Wallny, R; Wang, S M; Waters, D; Wester, W C; Whiteson, D; Wicklund, A B; Wilbur, S; Williams, H H; Wilson, J S; Wilson, P; Winer, B L; Wittich, P; Wolbers, S; Wolfe, H; Wright, T; Wu, X; Wu, Z; Yamamoto, K; Yamato, D; Yang, T; Yang, U K; Yang, Y C; Yao, W-M; Yeh, G P; Yi, K; Yoh, J; Yorita, K; Yoshida, T; Yu, G B; Yu, I; Zanetti, A M; Zeng, Y; Zhou, C; Zucchelli, S

    2013-11-15

    We present a measurement of the total decay width of the top quark using events with top-antitop quark pair candidates reconstructed in the final state with one charged lepton and four or more hadronic jets. We use the full Tevatron run II data set of sqrt[s]=1.96  TeV proton-antiproton collisions recorded by the CDF II detector. The top quark mass and the mass of the hadronically decaying W boson are reconstructed for each event and compared with distributions derived from simulated signal and background samples to extract the top quark width (Γtop) and the energy scale of the calorimeter jets with in situ calibration. For a top quark mass Mtop=172.5  GeV/c2, we find 1.10quark width to date.

  19. Implications of Satellite Swath Width on Global Aerosol Optical Thickness Statistics

    Science.gov (United States)

    Colarco, Peter; Kahn, Ralph; Remer, Lorraine; Levy, Robert; Welton, Ellsworth

    2012-01-01

    We assess the impact of swath width on the statistics of aerosol optical thickness (AOT) retrieved by satellite as inferred from observations made by the Moderate Resolution Imaging Spectroradiometer (MODIS). We sub-sample the year 2009 MODIS data from both the Terra and Aqua spacecraft along several candidate swaths of various widths. We find that due to spatial sampling there is an uncertainty of approximately 0.01 in the global, annual mean AOT. The sub-sampled monthly mean gridded AOT are within +/- 0.01 of the full swath AOT about 20% of the time for the narrow swath sub-samples, about 30% of the time for the moderate width sub-samples, and about 45% of the time for the widest swath considered. These results suggest that future aerosol satellite missions with only a narrow swath view may not sample the true AOT distribution sufficiently to reduce significantly the uncertainty in aerosol direct forcing of climate.

  20. Function of eltrombopag-induced platelets compared to platelets from control patients with immune thrombocytopenia.

    Science.gov (United States)

    Haselboeck, Johanna; Kaider, Alexandra; Pabinger, Ingrid; Panzer, Simon

    2013-04-01

    Data on the in vivo function of platelets induced by the thrombopoietin receptor agonist eltrombopag are scarce. To assess a possible influence of eltrombopag we compared platelet function of eltrombopag-treated immune thrombocytopenia (ITP) patients (group 1; n=10) after treatment response to that from control ITP patients (group 2; n=12). We further analysed platelet function at baseline and after one, three, and four weeks of eltrombopag treatment and estimated daily changes of platelet function during the eltrombopag-induced platelet rise. The formation of platelet-monocyte aggregates (PMA), P-selectin expression [MFI], and platelet adhesion under high shear conditions (surface coverage, SC) in vivo and after in vitro addition of agonists (ADP, TRAP-6, Collagen) were similar between both groups after response to eltrombopag treatment. Only TRAP-6 induced a lower SC in the eltrombopag group (p=0.03). All platelet function parameters except for Collagen-induced P-selectin expression changed significantly during treatment with eltrombopag. PMA, naïve and after addition of ADP or TRAP-6 increased with increasing platelet counts. P-selectin expression decreased, when measured without and upon addition of ADP, increased in the presence of TRAP-6, and remained unchanged after addition of Collagen. SC increased during the eltrombopag-induced platelet rise. All significant changes of platelet function correlated to changes in platelet counts. Two patients developed venous thromboses during eltrombopag treatment, but no association with any distinct single platelet function parameter or combinations thereof was identifiable. Thus, eltrombopag-induced platelets function similar to those from control ITP patients without discernible increased hyper-reactivity.

  1. A platelet monoclonal antibody inhibition assay for detection of glycoprotein IIb/IIIa-related platelet alloantibodies.

    Science.gov (United States)

    Reiner, A P; Teramura, G; Nelson, K A; Slichter, S J

    1995-08-18

    Post-transfusion purpura (PTP) and neonatal alloimmune thrombocytopenia (NAT) result from formation of alloantibodies to platelet membrane glycoprotein-associated antigens. The detection and identification of platelet-specific alloantibodies in patient sera is often complicated by the presence of co-existing HLA antibodies and/or more than one platelet specificity in the same serum. We describe a solid phase assay that specifically detects antibodies to platelet membrane associated alloantigens by measuring the ability of patient antisera to inhibit the binding of glycoprotein GPIIb or GPIIIa monoclonal antibodies to intact platelets. When tested in the GPIIIa assay against a panel of random platelet donors, the reactivities of two known PLAI antisera that also contained different HLA antibodies were highly correlated (r = 0.99) and allowed PLA phenotyping of the population. A standard direct binding platelet ELISA, on the other hand, was unable to accurately PLA phenotype the same population. The reactivities of two known Baka antisera (one containing additional anti-PLA2 and the other anti-Brb specificities) were highly correlated (r = 0.95) in the GPIIb assay, and Bak phenotype determination was similarly accomplished for a random platelet panel. Furthermore, a comparison of platelet phenotype results (using the monoclonal inhibition assay) and genotype results (using DNA analysis) for the PLA and Bak systems showed a concordance of 98% for 146 alleles tested. In conclusion, the platelet monoclonal antibody inhibition assay: (1) allows determination of platelet-specific alloantibodies in the presence of contaminating HLA antibodies and/or in sera containing multiple platelet alloantibodies; (2) allows accurate platelet phenotyping for the GPIIIa-associated PLA and GPIIb-associated Bak antigen systems; and (3) may be applicable to the detection of other known or even novel platelet glycoprotein-associated antigens.

  2. Biologic width and its importance in periodontal and restorative dentistry

    Directory of Open Access Journals (Sweden)

    Babitha Nugala

    2012-01-01

    Full Text Available An adequate understanding of the relationship between periodontal tissues and restorative dentistry is paramount to ensure adequate form, function, esthetics and comfort of the dentition. While most clinicians are aware of this important relationship, uncertainty remains regarding specific concepts such as biologic width, its maintenance and applications of crown lengthening in cases of biologic width violation. Relevant publications regarding biologic width, its violation and management were identified up to August 2011 using manual and electronic database search in Medline, Embase, Directory of Open Access Journals and Google Scholar. This review discusses the concept of biologic width around tooth and its relationship to periodontal health and restorative dentistry.

  3. A Statistical Approach for Obtaining the Controlled Woven Fabric Width

    Directory of Open Access Journals (Sweden)

    Shaker Khubab

    2015-12-01

    Full Text Available A common problem faced in fabric manufacturing is the production of inconsistent fabric width on shuttleless looms in spite of the same fabric specifications. Weft-wise crimp controls the fabric width and it depends on a number of factors, including warp tension, temple type, fabric take-up pressing tension and loom working width. The aim of this study is to investigate the effect of these parameters on the fabric width produced. Taguchi’s orthogonal design was used to optimise the weaving parameters for obtaining controlled fabric width. On the basis of signal to noise ratios, it could be concluded that controlled fabric width could be produced using medium temple type and intense take-up pressing tension at relatively lower warp tension and smaller loom working width. The analysis of variance revealed that temple needle size was the most significant factor affecting the fabric width, followed by loom working width and warp tension, whereas take-up pressing tension was least significant of all the factors investigated in the study.

  4. Modulatory effect of coffee on platelet function.

    Science.gov (United States)

    Bhaskar, Shobha; Rauf, Arun A

    2010-01-01

    Blood platelets play a major role in cardiovascular disease (CVD) and thrombosis. Conflicting information exists regarding the effect of coffee consumption on the cardiovascular system. We have investigated whether the consumption of moderate amount of coffee affect platelet functions and primary hemostasis in vivo in normal and high fat diet fed rats. Coffee fed group showed significant (P production from membrane arachidonic acid and it was decreased in coffee treated group. Platelet aggregation studies with ADP, collagen, arachidonic acid and epinephrine showed significant (P coffee fed group. Scanning electron microscopic studies revealed that platelet aggregation tendency increased in HFD group and was reduced in coffee fed group. These results indicate that coffee is active in inhibiting platelet aggregation, a critical step involved in thrombosis.

  5. Platelet mitochondrial function and dysfunction: physiological consequences

    Energy Technology Data Exchange (ETDEWEB)

    Popov, D.

    2015-07-01

    There is a general trend in revisiting mitochondria using the up-to-date technologies that uncovered novel attributes of this organelle, such as the intracellular displacement to locations where an energy supply is needed, the dynamic shape changes and turnover, the initiation of signaling to the rest of the cell, and the ability to crosstalk with other cellular organelles. The in-depth scrutiny of platelet mitochondria role in health and pathology is included within this ongoing revisiting trend. The current article puts into a nutshell the most recent data on platelet mitochondria function and disease-related ion, focusing on generation of stress- and apoptosis-related signaling molecules, overproduction of reactive oxygen species during activation and disease, on the biomarker potential of platelets mitochondria, and their prospective exploitation in translational applications. These novel findings complete the physiological profile of platelets and could have potential therapeutic effectiveness in platelet-associated disorders.

  6. Platelets as immune cells in infectious diseases.

    Science.gov (United States)

    Speth, Cornelia; Löffler, Jürgen; Krappmann, Sven; Lass-Flörl, Cornelia; Rambach, Günter

    2013-11-01

    Platelets have been shown to cover a broad range of functions. Besides their role in hemostasis, they have immunological functions and thus participate in the interaction between pathogens and host defense. Platelets have a broad repertoire of receptor molecules that enable them to sense invading pathogens and infection-induced inflammation. Consequently, platelets exert antimicrobial effector mechanisms, but also initiate an intense crosstalk with other arms of the innate and adaptive immunity, including neutrophils, monocytes/macrophages, dendritic cells, B cells and T cells. There is a fragile balance between beneficial antimicrobial effects and detrimental reactions that contribute to the pathogenesis, and many pathogens have developed mechanisms to influence these two outcomes. This review aims to highlight aspects of the interaction strategies between platelets and pathogenic bacteria, viruses, fungi and parasites, in addition to the subsequent networking between platelets and other immune cells, and the relevance of these processes for the pathogenesis of infections.

  7. Platelet bioreactor-on-a-chip

    Science.gov (United States)

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

    2014-01-01

    Platelet transfusions total >2.17 million apheresis-equivalent units per year in the United States and are derived entirely from human donors, despite clinically significant immunogenicity, associated risk of sepsis, and inventory shortages due to high demand and 5-day shelf life. To take advantage of known physiological drivers of thrombopoiesis, we have developed a microfluidic human platelet bioreactor that recapitulates bone marrow stiffness, extracellular matrix composition, micro-channel size, hemodynamic vascular shear stress, and endothelial cell contacts, and it supports high-resolution live-cell microscopy and quantification of platelet production. Physiological shear stresses triggered proplatelet initiation, reproduced ex vivo bone marrow proplatelet production, and generated functional platelets. Modeling human bone marrow composition and hemodynamics in vitro obviates risks associated with platelet procurement and storage to help meet growing transfusion needs. PMID:25606631

  8. Platelet-rich plasma in otolaryngology.

    Science.gov (United States)

    Stavrakas, M; Karkos, P D; Markou, K; Grigoriadis, N

    2016-12-01

    Platelet-rich plasma is a novel material that is being used more frequently in many surgical specialties. A literature review on the current and potential uses of platelet-rich plasma in otolaryngology was performed. There is limited evidence on the use of platelet-rich plasma in otolaryngology compared with other specialties: only 11 studies on various subspecialties (otology, rhinology and laryngology) were included in the final review. Based on the limited number of studies, we cannot draw safe conclusions about the value of platelet-rich plasma in otolaryngology. Nevertheless, the available literature suggests that platelet-rich plasma holds promise for future research and may have a number of clinical applications.

  9. Deposition of fibrinogen on the surface of in vitro thrombi prevents platelet adhesion.

    Science.gov (United States)

    Owaynat, Hadil; Yermolenko, Ivan S; Turaga, Ramya; Lishko, Valeryi K; Sheller, Michael R; Ugarova, Tatiana P

    2015-12-01

    The initial accumulation of platelets after vessel injury is followed by thrombin-mediated generation of fibrin which is deposited around the plug. While numerous in vitro studies have shown that fibrin is highly adhesive for platelets, the surface of experimental thrombi in vivo contains very few platelets suggesting the existence of natural anti-adhesive mechanisms protecting stabilized thrombi from platelet accumulation and continuous thrombus propagation. We previously showed that adsorption of fibrinogen on pure fibrin clots results in the formation of a nonadhesive matrix, highlighting a possible role of this process in surface-mediated control of thrombus growth. However, the deposition of fibrinogen on the surface of blood clots has not been examined. In this study, we investigated the presence of intact fibrinogen on the surface of fibrin-rich thrombi generated from flowing blood and determined whether deposited fibrinogen is nonadhesive for platelets. Stabilized fibrin-rich thrombi were generated using a flow chamber and the time that platelets spend on the surface of thrombi was determined by video recording. The presence of fibrinogen and fibrin on the surface of thrombi was analyzed by confocal microscopy using specific antibodies. Examination of the spatial distribution of two proteins revealed the presence of intact fibrinogen on the surface of stabilized thrombi. By manipulating the surface of thrombi to display either fibrin or intact fibrinogen, we found that platelets adhere to fibrin- but not to fibrinogen-coated thrombi. These results indicate that the fibrinogen matrix assembled on the outer layer of stabilized in vitro thrombi protects them from platelet adhesion.

  10. Controlling ρ width effects for a precise value of α in B → ρρ

    Science.gov (United States)

    Gronau, Michael; Rosner, Jonathan L.

    2017-03-01

    It has been pointed out that the currently most precise determination of the weak phase ϕ2 = α of the Cabibbo-Kobayashi-Maskawa (CKM) matrix achieved in B → ρρ decays is susceptible to a small correction at a level of (Γρ /mρ) 2 due to an I = 1 amplitude caused by the ρ width. Using Breit-Wigner distributions for the two pairs of pions forming ρ mesons, we study the I = 1 contribution to B → ρρ decay rates as function of the width and location of the ρ band. We find that in the absence of a particular enhancement of the I = 1 amplitude reducing a single band to a width Γρ at SuperKEKB leads to results which are completely insensitive to the ρ width. If the I = 1 amplitude is dynamically enhanced relative to the I = 0 , 2 amplitude one could subject its contribution to a "magnifying glass" measurement using two separated ρ bands of width Γρ. Subtraction of the I = 1 contribution from the measured decay rate would lead to a very precise determination of the I = 0 , 2 amplitude needed for performing the isospin analysis.

  11. Platelet derivatives in regenerative medicine: an update.

    Science.gov (United States)

    De Pascale, Maria Rosaria; Sommese, Linda; Casamassimi, Amelia; Napoli, Claudio

    2015-01-01

    Prior preclinical and clinical studies support the use of platelet-derived products for the treatment of soft and hard tissue lesions. These regenerative effects are controlled by autocrine and paracrine biomolecules including growth factors and cytokines contained in platelet alpha granules. Each growth factor is involved in a phase of the healing process, such as inflammation, collagen synthesis, tissue granulation, and angiogenesis collectively promoting tissue restitution. Platelet derivatives have been prepared as platelet-rich plasma, platelet gel, platelet-rich fibrin, and platelet eye drops. These products vary in their structure, growth factors, composition, and cytokine concentrations. Here, we review the current use of platelet-derived biological products focusing on the rationale for their use and the main requirements for their preparation. Variation in the apparent therapeutic efficacy may have resulted from a lack of reproducible, standardized protocols for preparation. Despite several individual studies showing favorable treatment effects, some randomized controlled trials as well as meta-analyses have found no constant clinical benefit from the application of platelet-derived products for prevention of tissue lesions. Recently, 3 published studies in dentistry showed an improvement in bone density. Seven published studies showed positive results in joint regeneration. Five published studies demonstrated an improvement in the wound healing, and an improvement of eye epithelial healing was observed in 2 reports. Currently, at least 14 ongoing clinical trials in phase 3 or 4 have been designed with large groups of treated patients (n > 100). Because the rationale of the therapy with platelet-derived compounds is still debated, a definitive insight can be acquired only when these large randomized trials will be completed.

  12. Minimal forbidden induced subgraphs of graphs of bounded clique-width and bounded linear clique-width

    OpenAIRE

    Meister, Daniel; Rotics, Udi

    2013-01-01

    In the study of full bubble model graphs of bounded clique-width and bounded linear clique-width, we determined complete sets of forbidden induced subgraphs, that are minimal in the class of full bubble model graphs. In this note, we show that (almost all of) these graphs are minimal in the class of all graphs. As a corollary, we can give sets of minimal forbidden induced subgraphs for graphs of bounded clique-width and for graphs of bounded linear clique-width for arbitrary bounds.

  13. Decreased TGF-β1 and VEGF Release in Cystic Fibrosis Platelets: Further Evidence for Platelet Defects in Cystic Fibrosis

    Science.gov (United States)

    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

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

    Directory of Open Access Journals (Sweden)

    Katie L Lannan

    2015-02-01

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

  15. Platelet lysates produced from expired platelet concentrates support growth and osteogenic differentiation of mesenchymal stem cells.

    Directory of Open Access Journals (Sweden)

    Sandra Mjoll Jonsdottir-Buch

    Full Text Available BACKGROUND: Mesenchymal stem cells are promising candidates in regenerative cell therapy. Conventional culture methods involve the use of animal substances, specifically fetal bovine serum as growth supplement. Since the use of animal-derived products is undesirable for human applications, platelet lysates produced from human platelets are an attractive alternative. This is especially true if platelet lysates from already approved transfusion units at blood banks can be utilized. The purpose of this study was to produce human platelet lysates from expired, blood bank-approved platelet concentrates and evaluate their use as growth supplement in the culture of mesenchymal stem cells. METHODOLOGY/PRINCIPAL FINDINGS: In this study, bone marrow-derived mesenchymal stem cells were cultured with one of three culture supplements; fetal bovine serum, lysates from freshly prepared human platelet concentrates, or lysates from expired human platelet concentrates. The effects of these platelet-derived culture supplements on basic mesenchymal stem cell characteristics were evaluated. All cultures maintained the typical mesenchymal stem cell surface marker expression, trilineage differentiation potential, and the ability to suppress in vitro immune responses. However, mesenchymal stem cells supplemented with platelet lysates proliferated faster than traditionally cultured cells and increased the expression of the osteogenic marker gene RUNX-2; yet no difference between the use of fresh and expired platelet concentrates was observed. CONCLUSION/SIGNIFICANCE: Our findings suggest that human platelet lysates produced from expired platelet concentrates can be used as an alternative to fetal bovine serum for mesenchymal stem cell culture to the same extent as lysates from fresh platelets.

  16. Quantifying River Widths of North America from Satellite Imagery

    Science.gov (United States)

    Allen, G. H.; Pavelsky, T.; Miller, Z.

    2013-12-01

    River width is a fundamental predictor variable in many hydrologic, geomorphic, and biogeochemical models, yet current large-scale models rely on theoretical hydraulic geometry relationships that do not fully capture natural variability in river form. Here we present the first high-resolution dataset of long-term mean width of North American rivers wider than 30 m. The dataset contains 7.93 million georeferenced width measurements derived from Landsat TM and ETM+ imagery that were acquired when rivers were most likely to be at mean discharge. We built the dataset by developing an automated procedure that selects and downloads raw imagery, creates cloud-free normalized difference water index images, histogram balances and mosaics them together, and produces a water mask using a dynamic water-land threshold technique. We then visually inspected and corrected the mask for errors and used RivWidth software to calculate river width at each river centerline pixel. We validated our dataset using >1000 United States Geological Survey and Water Survey of Canada in situ gauge station measurements. Error analysis shows a robust relationship between the remotely sensed widths and in situ gauge measurements with an r 2 = 0.86 (Spearman's = 0.81) and a mean absolute error of 27.5 m. We find that North American river widths lie on logarithmic frequency curve with some notable exceptions at widths SWOT) satellite mission.

  17. Equivalent Widths of 15 Extrasolar-Planet Host Stars

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    We present the equivalent widths of 15 extrasolar-planet host stars.These data were based on the high-resolution, high signal-to-noise ratio spectra obtained with the 2.16 m telescope at Xinglong station. The error in the Xinglong equivalent width is estimated by a comparison of these data with those given in previous studies of common stars.

  18. Stream water responses to timber harvest: Riparian buffer width effectiveness

    Science.gov (United States)

    Barton D. Clinton

    2011-01-01

    Vegetated riparian buffers are critical for protecting aquatic and terrestrial processes and habitats in southern Appalachian ecosystems. In this case study, we examined the effect of riparian buffer width on stream water quality following upland forest management activities in four headwater catchments. Three riparian buffer widths were delineated prior to cutting; 0m...

  19. Average widths of anisotropic Besov-Wiener classes

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    This paper concerns the problem of average σ-K width and average σ-L width of some anisotropic Besov-Wiener classes Srp q θb(Rd) and Srp q θB(Rd) in Lq(Rd) (1≤q≤p<∞). The weak asymptotic behavior is established for the corresponding quantities.

  20. Average widths of anisotropic Besov-Wiener classes

    Institute of Scientific and Technical Information of China (English)

    蒋艳杰

    2000-01-01

    This paper concems the problem of average σ-K width and average σ-L width of some anisotropic Besov-wiener classes Spqθr(Rd) and Spqθr(Rd) in Lq(Rd) (1≤≤q≤p<∞). The weak asymptotic behavior is established for the corresponding quantities.

  1. Volume Fraction of Graphene Platelets in Copper-Graphene Composites

    Science.gov (United States)

    Jagannadham, K.

    2013-01-01

    Copper-graphene composite films were deposited on copper foil using electrochemical deposition. Four electrolyte solutions that each consist of 250 mL of graphene oxide suspension in distilled water and increasing volume of 0.2 M solution of CuSO4 in steps of 250 mL were used to deposit the composite films with and without a magnetic stirrer. Graphene oxide in the films was reduced to graphene by hydrogen treatment for 6 hours at 673 K (400 °C). The samples were characterized by X-ray diffraction for identification of phases, scanning electron microscopy for distribution of graphene, energy dispersive spectrometry for evaluation of elemental composition, electrical resistivity and temperature coefficient of electrical resistance and thermal conductivity. Effective mean field analysis (EMA) was used to determine the volume fraction and electrical conductivity of graphene and interfacial thermal conductance between graphene and copper. The electrical resistivity was reduced from 2.031 to 1.966 μΩ cm and the thermal conductivity was improved from 3.8 to 5.0 W/cm K upon addition of graphene platelets to electrolytic copper. The use of stirrer during deposition of the films increased the average size and the thickness of the graphene platelets and as a result the improvement in electrical conductivity was lower compared to the values obtained without the stirrer. Using the EMA, the volume fraction of graphene platelets that was responsible for the improvement in the electrical conductivity was found to be lower than that for the improvement in the thermal conductivity. The results of the analysis are used to determine the volume fraction of the thinner and the thicker graphene platelets in the composite films.

  2. 生长抑素对急性胰腺炎患者血小板相关指标与胃肠动力的影响%Effect of somatostatin on the platelet-related indicators and gastrointestinal motility of patients with acute pancreatitis

    Institute of Scientific and Technical Information of China (English)

    卢明; 彭小刚

    2015-01-01

    目的:探讨生长抑素对急性胰腺炎( acute pancreatitis ,AP)患者血小板相关指标及胃肠动力的影响。方法将106例AP患者随机分为治疗组和对照组各53例。所有患者均给予胃肠减压、禁食、抗感染、补液等支持治疗,治疗组于发病24 h内给予6 mg/d生长抑素,连用7 d。检测两组患者血小板相关指标的变化,记录两组患者的胃肠动力及预后情况。结果与对照组比较,治疗组治疗后3 d、7 d血小板分布宽度( platelet distribution width ,PDW)显著降低,血小板计数(platelets,PLT)、血小板容积比(PCT)均显著升高(P<0.05);治疗组恶心呕吐缓解时间、腹胀缓解时间、血淀粉酶恢复时间均显著缩短,胃管日均引流量显著减少,平均住院时间显著缩短,中转手术率显著下降(均P<0.05)。与死亡组比较,存活组患者平均血小板体积(mean platelet volume,MPV)和PDW显著降低, PLT、PCT均显著升高( P<0.05)。结论 AP患者早期应用生长抑素,可有效调节血小板活性,改善胰腺微循环与胃肠动力,改善预后。%Objective To explore the effect of somatostatin on platelet-related indicators and gastrointestinal motility of patients with acute pancreatitis (AP).Method 106 cases of APwere randomly divided into two groups.All patients were firstly treated with gastrointestinal decompression , fasting, fight infection, and rehydration support treatment . The experimental group was the given somatostatin 6 mg/d for 7 days in a row .The change in platelet-related indicators of the two groups was monitored and the gastrointestinal dysmotility and prognosis of both groups were recorded .Findings Compared with the control group, the experimental group at 3rd, 7th day after treatment had significantly lowered platelet distribution width (PDW) and higher platelets (PLT) and PCT (P<0.05).The ease time of nausea and vomiting

  3. Can the mean platelet volume be a predictor of disease activity in primary Sjogren syndrome?

    Directory of Open Access Journals (Sweden)

    Ahmet Omma

    2016-04-01

    Full Text Available Background: Disease activity in primary Sjogren syndrome (PSS is measured by the EULAR Sjogren's syndrome disease activity index (ESSDAI and patient reported index (ESSPRI. Studies investigating the association between ESSDAI and ESSPRI and previously reported indicators of systemic inflammation are few in the literature. The aim of this study was to determine the clinical utility of the mean platelet volume (MPV in predicting disease activity in PSS patients. Methods: A total of 190 subjects including ninety-five PSS patients and ninety-five healthy controls were enrolled. Associations between MPV and other known indicators of systemic inflammation (red cell distribution width (RDW, neutrophil to lymphocyte ratio (NLR and patient clinical characteristic, ESSDAI and ESSPRI were investigated by using spearman correlation and linear regression analysis. Results: MPV levels were found to be significantly higher in the PSS group than the control group (10.5+/-1.2 versus 9.0+/-1; P<0.001 respectively. Correlation and regression analysis showed a positive correlation between MPV levels and ESSDAI scores (r=0.24, p=0.01. There was a negative correlation between ESSPRI and MPV levels (r=-0.32, p=0.001. NLR and RDW did not show any significant correlation with either ESSDAI or ESSPRI scores. Conclusions: MPV levels are significantly elevated in PSS patients compared to their control peers, positively correlate with ESSDAI but negatively with ESSPRI scores. MPV might be a useful inflammatory marker to measure disease activity in PSS. [Int J Res Med Sci 2016; 4(4.000: 1237-1241

  4. The influence of sulcus width on simulated electric fields induced by transcranial magnetic stimulation

    Science.gov (United States)

    Janssen, A. M.; Rampersad, S. M.; Lucka, F.; Lanfer, B.; Lew, S.; Aydin, Ü.; Wolters, C. H.; Stegeman, D. F.; Oostendorp, T. F.

    2013-07-01

    Volume conduction models can help in acquiring knowledge about the distribution of the electric field induced by transcranial magnetic stimulation. One aspect of a detailed model is an accurate description of the cortical surface geometry. Since its estimation is difficult, it is important to know how accurate the geometry has to be represented. Previous studies only looked at the differences caused by neglecting the complete boundary between cerebrospinal fluid (CSF) and grey matter (Thielscher et al 2011 NeuroImage 54 234-43, Bijsterbosch et al 2012 Med. Biol. Eng. Comput. 50 671-81), or by resizing the whole brain (Wagner et al 2008 Exp. Brain Res. 186 539-50). However, due to the high conductive properties of the CSF, it can be expected that alterations in sulcus width can already have a significant effect on the distribution of the electric field. To answer this question, the sulcus width of a highly realistic head model, based on T1-, T2- and diffusion-weighted magnetic resonance images, was altered systematically. This study shows that alterations in the sulcus width do not cause large differences in the majority of the electric field values. However, considerable overestimation of sulcus width produces an overestimation of the calculated field strength, also at locations distant from the target location.

  5. The influence of sulcus width on simulated electric fields induced by transcranial magnetic stimulation.

    Science.gov (United States)

    Janssen, A M; Rampersad, S M; Lucka, F; Lanfer, B; Lew, S; Aydin, U; Wolters, C H; Stegeman, D F; Oostendorp, T F

    2013-07-21

    Volume conduction models can help in acquiring knowledge about the distribution of the electric field induced by transcranial magnetic stimulation. One aspect of a detailed model is an accurate description of the cortical surface geometry. Since its estimation is difficult, it is important to know how accurate the geometry has to be represented. Previous studies only looked at the differences caused by neglecting the complete boundary between cerebrospinal fluid (CSF) and grey matter (Thielscher et al 2011 NeuroImage 54 234-43, Bijsterbosch et al 2012 Med. Biol. Eng. Comput. 50 671-81), or by resizing the whole brain (Wagner et al 2008 Exp. Brain Res. 186 539-50). However, due to the high conductive properties of the CSF, it can be expected that alterations in sulcus width can already have a significant effect on the distribution of the electric field. To answer this question, the sulcus width of a highly realistic head model, based on T1-, T2- and diffusion-weighted magnetic resonance images, was altered systematically. This study shows that alterations in the sulcus width do not cause large differences in the majority of the electric field values. However, considerable overestimation of sulcus width produces an overestimation of the calculated field strength, also at locations distant from the target location.

  6. The influence of sulcus width on simulated electric fields induced by transcranial magnetic stimulation

    Science.gov (United States)

    Janssen, A M; Rampersad, S M; Lucka, F; Lanfer, B; Lew, S; Aydin, Ü; Wolters, C H; Stegeman, D F; Oostendorp, T F

    2013-01-01

    Volume conduction models can help in acquiring knowledge about the distribution of the electric field induced by transcranial magnetic stimulation (TMS). One aspect of a detailed model is an accurate description of the cortical surface geometry. Since its estimation is difficult, it is important to know how accurate the geometry has to be represented. Previous studies only looked at the differences caused by neglecting the complete boundary between the CSF and GM (Thielscher et al. 2011; Bijsterbosch et al. 2012), or by resizing the whole brain (Wagner et al. 2008). However, due to the high conductive properties of the CSF, it can be expected that alterations in sulcus width can already have a significant effect on the distribution of the electric field. To answer this question, the sulcus width of a highly realistic head model, based on T1-, T2- and diffusion-weighted magnetic resonance images (MRI), was altered systematically. This study shows that alterations in the sulcus width do not cause large differences in the majority of the electric field values. However, considerable overestimation of sulcus width produces an overestimation of the calculated field strength, also at locations distant from the target location. PMID:23787706

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

    Science.gov (United States)

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

    2014-07-31

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

  8. Crack widths in concrete with fibers and main reinforcement

    DEFF Research Database (Denmark)

    Christensen, Frede; Ulfkjær, Jens Peder; Brincker, Rune

    the ductility of the fiber reinforced concrete (FRC) is set up and experimental work is conducted in order to verify the crack width model. The ductility of the FRC is taken into account by using the stress crack width relation. The constitutive model for the FRC is based on the idea that the initial part......The main object of the research work presented in this paper is to establish design tools for concrete structures where main reinforcement is combined with addition of short discrete steel fibers. The work is concerned with calculating and measuring crack widths in structural elements subjected...... to bending load. Thus, the aim of the work is to enable engineers to calculate crack widths for flexural concrete members and analyze how different combinations of amounts of fibers and amounts of main reinforcement can meet a given maximum crack width requirement. A mathematical model including...

  9. Blood platelets in the progression of Alzheimer's disease.

    Directory of Open Access Journals (Sweden)

    Nina S Gowert

    Full Text Available Alzheimer's disease (AD is characterized by neurotoxic amyloid-ß plaque formation in brain parenchyma and cerebral blood vessels known as cerebral amyloid angiopathy (CAA. Besides CAA, AD is strongly related to vascular diseases such as stroke and atherosclerosis. Cerebrovascular dysfunction occurs in AD patients leading to alterations in blood flow that might play an important role in AD pathology with neuronal loss and memory deficits. Platelets are the major players in hemostasis and thrombosis, but are also involved in neuroinflammatory diseases like AD. For many years, platelets were accepted as peripheral model to study the pathophysiology of AD because platelets display the enzymatic activities to generate amyloid-ß (Aß peptides. In addition, platelets are considered to be a biomarker for early diagnosis of AD. Effects of Aß peptides on platelets and the impact of platelets in the progression of AD remained, however, ill-defined. The present study explored the cellular mechanisms triggered by Aß in platelets. Treatment of platelets with Aß led to platelet activation and enhanced generation of reactive oxygen species (ROS and membrane scrambling, suggesting enhanced platelet apoptosis. More important, platelets modulate soluble Aß into fibrillar structures that were absorbed by apoptotic but not vital platelets. This together with enhanced platelet adhesion under flow ex vivo and in vivo and platelet accumulation at amyloid deposits of cerebral vessels of AD transgenic mice suggested that platelets are major contributors of CAA inducing platelet thrombus formation at vascular amyloid plaques leading to vessel occlusion critical for cerebrovascular events like stroke.

  10. Brief Report: Platelet-Poor Plasma Serotonin in Autism

    Science.gov (United States)

    Anderson, George M.; Hertzig, Margaret E.; McBride, P. A.

    2012-01-01

    Possible explanations for the well-replicated platelet hyperserotonemia of autism include an alteration in the platelet's handling of serotonin (5-hydroxyserotonin, 5-HT) or an