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May-Hegglin anomaly is the presentation of a qualitative platelet disorder characterised by large platelets, thrombocytopenia and granulocyte inclusions as a result of mutations in the MYH9 gene. Though often overlooked given its rarity, it should be considered in patients who present with epistaxis, bruising, menorrhagia and easy bleeding as it can be mistaken for other diagnoses resulting in unnecessary treatments and tests. Our case study reports one presentation of this anomaly and can help broaden awareness of the presentation of this type of patient.

The May-Hegglin Anomaly (MHA) is a rare autosomal dominant giant platelet disorder characterized by abnormally large platelets with defective leucocytes and thrombocytopenia with varying degrees of bleeding manifestation. Here we report successful pregnancy outcome in a primigravida with MHA. (Preterm Pre-labour Rupture of Membranes) PPROM mother, with abnormalities of the extremities due to ABS is discussed.

espanolEn Ecuador el uso de plaguicidas organofosforados en la agricultura se ha convertido en un problema de salud publica, segun datos bibliograficos las personas expuestas de manera ocupacional a estos agroquimicos manifiestan alteraciones en su salud. Este estudio fue enfocado en la valoracion de parametros hematologicos y morfologicos de agricultores expuestos de forma ocupacional a estos plaguicidas. Es un estudio observacional, descriptivo de corte transversal y correlacional. En la comunidad de Guaslan-Ecuador aproximadamente 400 personas se dedican a la agricultura, de los cuales 186 individuos formaron parte del estudio forma libre y voluntaria. El 53% de la poblacion fueron mujeres, el 47% hombres. La valoracion del hemograma permitio determinar alteraciones cuantitativas como: poliglobulia, leucocitosis, neutrofilia, linfocitosis y cambios en las plaquetas. La morfologia celular se valoro con el analisis del frotis de sangre periferica que evidencio alteraciones cualitativas en globulos rojos, blancos y plaquetas. Los hallazgos mas relevantes fueron: neutrofilos con granulacion toxica, linfocitos reactivos, hipersegmentacion, plaquetas grandes y estomatocitosis. La colinesterasa eritrocitaria obtuvo 13% de la poblacion. El 99% de la poblacion presento al menos una alteracion cuantitativa y un 80% alteraciones cualitativas. La actividad de la colinesterasa resulto inversamente proporcional al tiempo de exposicion. Se concluye que los plaguicidas organofosforados son capaces de producir alteraciones a nivel celular y enzimatico. Se recomienda incluir el hemograma y el frotis de sangre periferica como marcadores de hemotoxicidad en pruebas ocupacionales o de perfil epidemiologico para personas expuestas a este tipo de agroquimicos. EnglishIn Ecuador, the use of organophosphorus pesticides in agriculture has become a public health problem, according to bibliographic data, people exposed to these agrochemicals in occupational ways show alterations in their health. This study was focused on the assessment of hematological and morphological parameters of farmers exposed in an occupational way to these pesticides. It is an observational, descriptive cross-sectional and correlational study. In the community of Guaslan-Ecuador approximately 400 people are engaged in agriculture, of which 186 individuals were part of the study freely and voluntarily. 53% of the population were women, 47% men. The assessment of the blood count allowed to determine quantitative alterations such as: polyglobulia, leukocytosis, neutrophilia, lymphocytosis and platelet changes. Cellular morphology was assessed with the analysis of the peripheral blood smear that showed qualitative alterations in red, white and platelet cells. The most relevant findings were: neutrophils with toxic granulation, reactive lymphocytes, hypersegmentation, large platelets and stomatocytosis. Erythrocyte cholinesterase obtained 13% of the population. The 99% of the population presented at least one quantitative alteration and 80% qualitative alterations. Cholinesterase activity was inversely proportional to the exposure time. It is concluded that organophosphorus pesticides are capable of producing alterations at the cellular and enzymatic level. It is recommended to include the blood count and peripheral blood smear as markers of hemotoxicity in occupational tests or epidemiological profile for people exposed to this type of agrochemicals.

Objective Platelet surface receptors are also present subcellularly in organelle membranes and can be expressed on the surface upon platelet activation. However, some receptors were reported to be decreased after activation. We analyzed the mechanism of activation‐dependent expression for different receptors. Methods Flow cytometry using platelet‐rich plasma or washed platelets was used to analyze receptor‐expression changes after platelet activation by glycoprotein (GP) VI–specific agonists, crosslinked collagen‐related peptide (CRP‐XL) and convulxin (Cvx), and thrombin. Platelets prelabeled with fluorescent antibody specific for a receptor were allowed to adhere on immobilized collagen or fibrinogen and post‐stained with antibody against the same receptor labeled with another fluorophore, allowing us to differentiate preexisting receptors from newly expressed receptors. Results Surface expression of αIIbβ3 increased in CRP‐XL–, Cvx‐, or thrombin‐stimulated platelets, but GPIb decreased due to shedding and internalization. Both total and dimeric GPVI increased in thrombin‐induced platelets, but decreased in platelets stimulated by Cvx, as a result of internalization. The larger platelets showed a greater increase in surface receptor (α2β1, αIIbβ3, GPVI, GPIb) expression upon activation compared to the smaller ones. Pre‐ and postlabeling with antibody specific for the same receptor, but conjugated with different fluorophores, allowed us to differentiate the receptors expressed on the surface of resting platelets from receptors newly exposed to the surface upon platelet activation. Conclusions Increased receptor expressions after activation are mainly manifested in the larger platelets. On platelets adhered on fibrinogen, the newly expressed receptors, especially GPVI, are localized in the lamellipodia of the spread platelets.

In geographical regions with sub-zero temperatures, natural freezing can potentially be used as an energy-efficient purification technique for industrial wastewaters. The utilization of this technique requires knowledge of the effect of impurities on the strength of the ice to enable the effective harvesting of produced ice. Previous studies of the mechanical properties of model-scale ice have tended to focus on the initial solution, and little consideration has been given to the amount of impurities trapped inside the ice. The aim of this research is to evaluate the separation efficiency during the natural freezing process by quantifying the impurities trapped inside the ice formed from known concentrations of aqueous solutions and to investigate the effect of impurities on the bulk mechanical properties of the ice. In this study, twenty similar size ice beams were prepared in freezing boxes in a temperature-controlled cold room from five different aqueous solutions – tap water, and ethanol and sodium chloride aqueous solutions of two different molalities, i.e. 0.1 mol/kg and 0.3 mol/kg. The bending strength and natural frequencies of the ice samples were measured in the freezing conditions, and the concentrations of impurities in melted ice samples were determined. The research shows that with the ethanol and sodium chloride solutions, the concentration of impurities inside the ice clearly decreased in comparison to the initial solution. The structure of the ice from the different solutions differed significantly; as the tap water formed columnar ice, ethanol ice grew through large platelets, while the structure of the sodium chloride ice was a mixture of the two forms. The tap water yielded the highest strength ice and the ice formed from the ethanol aqueous solutions the weakest ice. The measurements indicated that the concentration of impurity in the ice reduces the mechanical strength and the magnitude of the effect varies with the chemical characteristic of impurity.

ObjectivesAutomated haematology analysers measure various parameters of relevance to clinical research along with routine complete blood count (CBC)-related components. We aimed to establish ethnicity-specific and sex-specific reference intervals for 26 research-specific parameters as well as 18 routinely reported components using a large cohort of healthy Korean adults. The necessity of requiring separate sex-specific reference intervals for each parameter was also examined.DesignA retrospective database review.SettingSingle tertiary-care hospital of approximately 375 physicians and 530 nurses.ParticipantsThis study included 1383 reference individuals (840 men and 543 women).Primary and secondary outcome measuresFollowing the Clinical and Laboratory Standards Institute guidelines for establishing reference intervals, routine CBCs as well as research parameters were measured using an ADVIA 2120i instrument.ResultsAll the routine components except for mean platelet volume and per cent lymphocytes differed significantly between men and women. Most research parameters also differed between the sexes; the exceptions were large platelets, platelet dry mass distribution width, per cent basophil saturation, per cent peroxidase saturation and per cent abnormal peroxidase absorption. Despite these differences, separate reference intervals for men and women were required only for two research-specific parameters: ‘percentage high cellular haemoglobin’ and ‘percentage of hyperchromic red blood cells (RBCs)’.ConclusionEven though most parameters showed significant differences between men and women, none of the evaluated parameters except two RBC-related factors required separate reference intervals for each sex.

A colored platy substrate with appreciable aspect ratio can improve the hiding power while extending the color range of pearlescent pigments. One of the oldest synthetic pigments, Egyptian blue, possesses a layered structure and a platy morphology, making it a promising colored substrate for pearlescent pigments, which derives its blue color from CuII. Unfortunately, existing synthesis routes are either not technically benign or lack the natural platy morphology. Here, we introduce a new synthesis route starting with large, square‐shaped platelets of a synthetic layered sodium silicate (NaRUB‐18). As evidenced by Rietveld refinement and scanning electron microscopy, NaRUB‐18 can be converted with conservation of this attractive morphology (pseudomorphosis) into Egyptian blue.

OBJECTIVE: Platelet surface receptors are also present subcellularly in organelle membranes and can be expressed on the surface upon platelet activation. However, some receptors were reported to be decreased after activation. We analyzed the mechanism of activation-dependent expression for different receptors. METHODS: Flow cytometry using platelet-rich plasma or washed platelets was used to analyze receptor-expression changes after platelet activation by glycoprotein (GP) VI-specific agonists, crosslinked collagen-related peptide (CRP-XL) and convulxin (Cvx), and thrombin. Platelets prelabeled with fluorescent antibody specific for a receptor were allowed to adhere on immobilized collagen or fibrinogen and post-stained with antibody against the same receptor labeled with another fluorophore, allowing us to differentiate preexisting receptors from newly expressed receptors. RESULTS: Surface expression of αIIbβ3 increased in CRP-XL-, Cvx-, or thrombin-stimulated platelets, but GPIb decreased due to shedding and internalization. Both total and dimeric GPVI increased in thrombin-induced platelets, but decreased in platelets stimulated by Cvx, as a result of internalization. The larger platelets showed a greater increase in surface receptor (α2β1, αIIbβ3, GPVI, GPIb) expression upon activation compared to the smaller ones. Pre- and postlabeling with antibody specific for the same receptor, but conjugated with different fluorophores, allowed us to differentiate the receptors expressed on the surface of resting platelets from receptors newly exposed to the surface upon platelet activation. CONCLUSIONS: Increased receptor expressions after activation are mainly manifested in the larger platelets. On platelets adhered on fibrinogen, the newly expressed receptors, especially GPVI, are localized in the lamellipodia of the spread platelets.

Highly dispersed α-Al2O3 microplatelets of various sizes and aspect ratios were prepared by additive-assisted molten salt synthesis. The effects of SiO2 and SiO2 + CaO additions on phase formation and morphology development of α-Al2O3 particles were investigated. Introducing additives are very effective in controlling α-Al2O3 morphology. SiO2 additive significantly enhances shape anisotropy of α-Al2O3 platelets, where a particle aspect ratio ∼23.8 was achieved, about 2.7–6.0 times higher than those of the platelets prepared without additives. When using SiO2 + CaO mixture, low concentration additive facilitates the growth of large platelets (∼9.8 µm), while increasing its content dramatically reduces the platelet size to ∼3.7 µm. These findings provide a new insight for the design and synthesis of novel advanced anisotropic microcrystals with improved quality.

BACKGROUND Platelets are large when young and immature and shrink as they age. The mean platelet volume (MPV) and platelet distribution width (PDW) reflect the volume and distribution of platelets, respectively. We compared the MPVs and PDWs of patients with immune thrombocytopenic purpura (ITP) or essential thrombocythemia (ET) to those of healthy individuals to test whether these values can reflect the pathomechanisms of these diseases. METHODS Platelet counts, MPVs, and PDWs were measured in 153 healthy individuals and in 20 and 34 patients with ITP and ET, respectively, using an XN-3000 instrument. RESULTS The MPVs and PDWs were significantly higher in ITP patients than in healthy individuals or ET patients. The MPVs were significantly lower in ET patients than in both ITP patients and healthy individuals; however, the PDWs in ET patients were similar to those in healthy individuals. The MPVs and PDWs did not correlate with platelet count in ITP or ET patients. CONCLUSIONS Our data suggested an increased production of young, large platelets and nondiscriminatory destruction of circulating platelets irrespective of their ages in ITP. Decreased MPVs and unelevated PDWs in ET suggest that clonal process-produced platelets remain small throughout their lifespans.

Resume Les thrombopenies constituent un motif frequent de confection d’un frottis sanguin en pratique courante dans un laboratoire d’analyse medicale. Les automates modernes d’hematologie cellulaire accompagnent les resultats chiffres par des histogrammes et des messages d’alerte. La maitrise de ces derniers est primordiale pour eviter la validation des resultats errones dans le cas ou l’examen microscopique n’est pas possible. Objectif Nous avons evalue les performances diagnostiques des differentes anomalies graphiques dans la detection des macroplaquettes et des agregats plaquettaires. Patients et methodes Trois cents cas de thrombopenie ont ete inclus dans l’etude sur la base d’un chiffre plaquettaire inferieur a 150 × 109/L. Cette evaluation est exprimee par les resultats de la sensibilite, de la specificite, de la valeur predictive positive et de la valeur predictive negative par rapport a l’examen microscopique du frottis sanguin. Resultats Les performances diagnostiques sont variables en fonction des anomalies retrouvees a l’examen microscopique du frottis sanguin. En effet, l’enregistrement d’un histogramme non lisse constitue l’anomalie la plus sensible a la presence des macroplaquettes. Toutefois, le non-retour a la ligne de base de l’histogramme plaquettaire est une anomalie d’une bonne specificite dans la signalisation des agregats plaquettaires. En outre, la visualisation des anomalies de repartition sur le scattergramme DIFF est tres specifique vis-a-vis des agregats plaquettaires. Conclusion Un histogramme plaquettaire normal permet de valider avec une grande confiance une thrombopenie dans le cas ou un frottis sanguin ne peut etre lu immediatement.

This study demonstrates that mean platelet volume (MPV) levels decrease after radioiodine (RAI) ablation therapy in hyperthyroid patients. Regarding the fact that large platelets are hemostatically more active, we suggest that hyperthyroid patients are at risk of cardiovascular disease despite all other cardiovascular risk factors. After RAI ablation therapy as MPV levels return to normal, cardiovascular risk for hyperthyroid patients reduces.

The phase behaviour of mixed suspensions of large and small hard platelets is treated by osmotic equilibrium theory. Depending on the size ratios of the small and large platelets, three distinct phase behaviour scenarios appear: isotropic-isotropic-nematic, isotropic-nematic and isotropic-nematic-nematic coexistence regions, in agreement with computer simulations. The experimental multiphase coexistence observed in mixed suspensions of large Titanate platelets and small Laponite platelets can be reproduced semi-quantitatively using osmotic equilibrium theory calculations.

H implantation in Si/Si:B/Si structures is a promising route to improve the Smart Cut™ process and transfer thin Si layers of reduced roughness and controlled thickness onto regular Si wafers. However, the mechanisms driving this process are unknown and thus difficult to model or optimize. For this reason, we have experimentally studied the redistribution of H which takes place in such structures after implantation and during annealing using SIMS and TEM. We show that the Si:B layer already traps H during implantation and form platelets parallel to the wafer surface. During annealing, the H atoms implanted in the Si regions are slowly transferred toward the Si:B layer where they are trapped on large platelets which grow further during annealing. Routes to optimize this process go through the minimization of H precipitation in the pure Si regions. This can probably be achieved by optimizing the implantation conditions.

A strong relationship exists between acute coronary syndrome (ACS) and platelets (PLTs) volume. Mean platelet volume (MPV) is a parameter of PLT functions and a marker for increased PLT activation. The aim of this study was to determine early changes in number of total PLT and MPV in different manifestation of ACS and to find out predictive value of MPV in the spectrum of ACS. This was a prospective study. One hundred thirty-four ACS patients were enrolled, 76 of them finished the study. PLT and MPV in patients with unstable angina, non-ST elevation, and ST elevation myocardial infarctions were determined on arrival and 1, 3, 72 hours, and 7 days after the admission to hospital. There was decrease in PLT and MPV in all three groups after 3 hours of arrival in hospital in comparison with admission values. In the later time period (72 hours and 7 days), there was an increase in PLT and MPV only in patients with acute myocardial infarction (AMI). We have revealed completely new dynamics in early changes in MPV and PLT count in patients with AMI. Biphasic changes were found in early phase after admission to the hospital. Fast response in these parameters raises new questions about their origin.

Despite the increased worldwide awareness, over the last decade, of the platelet-type von Willebrand Disease (PT-VWD), many uncertainties remain around this rare platelet bleeding disorder. This report aims to correctly identify and study the phenotype of new patients and highlights the diagnostic and therapeutic challenges this disease remains to pose. We describe four PT-VWD cases confirmed by genetic analysis in which either the diagnosis and/or the treatment posed challenge. We provide the details of the clinical presentation, laboratory analysis, and the treatment and the responses in each case. We show that in addition to type 2B VWD, PT-VWD can be misdiagnosed as idiopathic thrombocytopenic purpura, neonatal alloimmune thrombocytopenia, and unexplained gestational thrombocytopenia. The disease can be diagnosed as early as 1 year of age and with phenotypically normal parents. Bleeding in some patients can be managed successfully using Humate P and DDAVP combined with tranexamic acid with no significant thrombocytopenia. We provide for the first time an evidence of an efficient response to rFVIIa in PT-VWD. Anaphylactic reaction to VWF preparations may be related to PT-VWD and the development of HLA antibodies is not uncommon. Progressive thrombocytopenia with normal VWF levels can be seen with PT-VWD and the platelet count was normalized at 2.5 weeks postpartum in one case. We conclude that these studies represent a record of clinical observations/interventions that help improve diagnoses/management of PT-VWD, highlight the variations in age and clinical presentations, laboratory diagnostic approaches, the importance of genetic testing for accurate diagnosis and consideration of therapeutic alternatives. Fil: Sánchez Luceros, Analía Gabriela. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Medicina Experimental. Academia Nacional de Medicina de Buenos Aires. Instituto de Medicina Experimental; Argentina. Academia Nacional de Medicina de Buenos Aires. Instituto de Investigaciones Hematológicas ; Argentina Fil: Woods, Adriana Inés. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Medicina Experimental. Academia Nacional de Medicina de Buenos Aires. Instituto de Medicina Experimental; Argentina Fil: Bermejo, Emilse. Academia Nacional de Medicina de Buenos Aires. Instituto de Investigaciones Hematológicas ; Argentina Fil: Shukla, Shilpa. Academia Nacional de Medicina de Buenos Aires; Argentina Fil: Acharya, Suchitra. Cohen's Children Medical Center of New York; Estados Unidos Fil: Lavin, Michelle. St. James Hospital; Irlanda Fil: Rydz, Natalia. University of Calgary; Canadá Fil: Othman, Maha. Queens University; Canadá

We measured and modeled the electrical, optical and thermal properties of transparent and conducting thin films based on graphene and graphitic platelets. Thermal conductivity of our films decreases with increasing electrical conductivity. Our experiments indicate that, for sufficiently large platelets, the influence factor in controlling the thermal conductivity is represented by the junctions between neighboring graphene platelets. The thickness of such junctions is determined by the average number of graphene layers (N) forming each platelet. The fact that both the thermal and electrical properties depend on N allows us to establish a model that leads to a theoretical relationship between the thermal and electrical conductivity in our samples, which is general enough to be applied to a large class of graphene-based thin films.

May-Hegglin anomaly (MHA) is an autosomal dominant disorder, characterized by a variable degree of thrombocytopaenia, large platelets and inclusion bodies in white blood cells. Bleeding manifestations are generally mild, but severe bleeding episodes have been reported. This is a systematic review of literature for MHA during pregnancy. The review revealed 26 articles (25 case reports and one case series) including 75 pregnancies (five twin pregnancies) in 40 women. In 11 women, first presentation was incidental thrombocytopaenia during routine antenatal blood test. Of these, five women were misdiagnosed as idiopathic thrombocytopenic purpura (ITP), including three who underwent splenectomy for resistant ITP. Postpartum haemorrhage (PPH) and bleeding after miscarriage were presenting symptoms in two women. Antiplatelet antibody was found in three pregnancies. Only one of them required intervention with intravenous immunoglobulin (IVIG) to prevent neonatal alloimmune thrombocytopaenia. PPH was reported in four pregnancies; three were primary PPH, of which one had blood transfusion, one had platelet and cryoprecipitate transfusion and the third was managed conservatively. There was one secondary PPH that was treated conservatively. Neonatal outcome included 78 live neonates and two intrauterine fetal deaths. Thirty-four neonates had thrombocytopaenia and subsequently were diagnosed with MHA, three of them required platelet transfusion prophylactically as they developed very low platelet counts and one neonate with platelet count of 29 × 10 cells/l and received IVIG, as the mother had a positive antiplatelet antibody during pregnancy. No obvious bleeding complications were reported among the neonates. MHA can present challenges during pregnancy and be associated with adverse maternal and neonatal outcome because of bleeding complications. Joint management by obstetrician and haematologists is required to minimize these risks.

Accurate and reliable platelet counting is critical for the clinical management of platelet disorders, especially in thrombocytopenia. The platelet count is used to determine if the patient requires a platelet transfusion. As the prophylactic transfusion trigger is now set anywhere between 10-20 × 10(9)/L (depending upon the institution) it is therefore important that reliable and accurate counts are obtained in severely thrombocytopenic samples. The accuracy and precision of automated platelet counts is totally reliant upon optimal discrimination of platelets from other cells and interfering particles. However, clinicians often still rely upon counts that have been generated using so called "1-dimensional" cell size analysis systems, which not only fail to discriminate platelets from cell fragments of similar size but exclude large platelets from the final count. Also the current reference method for platelet counting (the manual phase count), upon which analysers are usually calibrated is highly imprecise, time consuming and unreliable. Thus there has been a demand for improvements in platelet counting technology in order to improve accuracy of counting in thrombocytopenia so that correct clinical decisions can be made. More recent developments including the introduction of "2-dimensional" optical counting and immunoplatelet counting within automated systems are significant advances. The availability of new technologies coupled with the recent development of a new candidate international reference method (flow cytometric immunocounting using the PLT/RBC ratio) should therefore improve the overall reliability of platelet counting especially in thrombocytopenia. In this review, the history and recent advances in platelet counting methodologies will be presented. The relative advantages and disadvantages of each technology will then be discussed along with their potential impact on improved accuracy of platelet counting.

Blood samples from 3 unrelated Akita dogs with a common history of persistent macrothrombocytopenia in the absence of clinical bleeding were sent to the Auburn University College of Veterinary Medicine (AUCVM) Clinical Pathology Laboratory for evaluation. Due to low platelet counts, one Akita dog had been treated with corticosteroids for presumed immune-mediated platelet destruction, and one Akita dog was treated with doxycycline for one month for presumed infection by a tick-borne agent. In spite of treatment, platelet counts remained low in both dogs. Given the absence of abnormal bleeding in all 3 dogs and lack of response to treatment in 2, congenital macrothrombocytopenia was suspected. Interestingly, platelets from all 3 dogs exhibited a consistent elongated platelet morphology. There were no morphologic abnormalities observed in other cell lines. While there have been anecdotal reports of a possible inherited macrothrombocytopenia in Akita dogs, scientific studies have not been done to verify these reports. This manuscript represents the first case report describing what is likely a congenital macrothrombocytopenia in Akita dogs based on persistently low platelet counts in the absence of clinical signs, and characterized by a unique platelet morphology.

WOS: 000375145200016, PubMed ID: 26808373, Severe congenital neutropenia type 4 is a disorder of the hematopoietic system associated with mutations in the glucose-6-phosphatase catabolic 3 (G6PC3) gene. This disorder is characterized by neutropenia, congenital heart defects, urogenital malformations, and prominent superficial veins. To our knowledge, although intermittent thrombocytopenia is observed in this mutation, the coexistence of large thrombocytes is rarely seen. Here we present a case of severe congenital neutropenia type 4 with G6PC3 mutation and large platelets in the peripheral smear.

Summary Introduction: The aim of this study was to show variability in the measurement of the mean platelet volume (MPV) depending on the instrument used. Methods: This prospective analysis was carried out to measure MPV with three instruments, in 30 healthy controls and 113 hospital patients. Results: Firstly, for values in the normal range, the values obtained with the Siemens Advia® 2120 are lower than those given by the Beckman Coulter LH750® (−0.89), which are in turn lower than those obtained with the Sysmex XE-2100D® (−1.11), which represents a 20–25% variation in the measurement. These results emphasize the lack of universal external calibration for MPV analysis and thus make any intercentre comparison of MPV impossible unless the automated haematology analyser used is indicated. Secondly, we stress the differences in behaviour of the instruments in the presence of abnormally large platelets, i.e. an underestimate of the platelet count and the MPV may be provided because instruments using impedance technology may fail to take into account these platelets, but they rightly flag them. Conclusion: To harmonize our procedures, we propose definitions of platelet size (normal size, macroplatelets and giant platelets) based on the coordinated interpretation of the MPV, the distribution of platelet volume and the morphological appearance.

Bernard-Soulier syndrome (BSS) is an inherited, usually autosomal recessive, platelet bleeding abnormality, characterized by a prolonged bleeding time, large platelets and thrombocytopenia.[1][1] In 1975, Nurden and Caen reported that platelets from BSS patients lacked a major surface membrane

Giant platelet disorders (GPD) refer to rare, usually inherited states characterized by abnormally large platelets, thrombocytopenia and bleeding tendency of variable severity. This review summarizes major clinical and laboratory features of three GPDs (Bernard-Soulier syndrome, May-Hegglin anomaly and gray platelet syndrome). Differential diagnosis between immunological thrombocytopenia and GPDs is important. Although rare, giant platelet disorders should be borne in mind, since bleeding tendency in some individuals may be severe and knowledge of bleeding diathesis is of importance before delivery or surgical procedures also in less symptomatic individuals.

The growth behavior of reaction-formed intermetallic compounds (IMCs) at Sn3.5Ag0.5Cu/Ni and Cu interfaces under thermal-shear cycling conditions was investigated. The results show that the morphology of (Cu x Ni1–x )6Sn5 and Cu6Sn5 IMCs formed both at Sn3.5Ag0.5Cu/Ni and Cu interfaces gradually changed from scallop-like to chunk-like, and different IMC thicknesses developed with increasing thermal-shear cycling time. Furthermore, Cu6Sn5 IMC growth rate at the Sn3.5Ag0.5Cu/Cu interface was higher than that of (Cu x Ni1–x )6Sn5 IMC under thermal-shear cycling. Compared to isothermal aging, thermal-shear cycling led to only one Cu6Sn5 layer at the interface between SnAgCu solder and Cu substrate after 720 cycles. Moreover, Ag3Sn IMC was dispersed uniformly in the solder after reflow. The planar Ag3Sn formed near the interface changed remarkably and merged together to large platelets with increasing cycles. The mechanism of formation of Cu6Sn5, (Cu x Ni1–x )6Sn5 and Ag3Sn IMCs during thermal-shear cycling process was investigated.

The ultrastructural pathology of GATA-1, V205M and G208S macrothrombocytes was discussed in earlier investigations. This study has used the same technology to evaluate macrothrombocytes from a patient with the GATA-1, R216Q mutation. Some of the pathological features observed in macrothrombocytes from patients with the V205M and G208S variations including hypo- and agranular platelets, tubular inclusions and platelets within platelets, as well as platelets within platelets within platelets were identified. However, tubular membrane sheets in megakaryocytes and platelets of the V205M and G208S types and large groups of platelets attached to platelets to form megathrombocytes were not observed. The unique pathology of the megathrombocytes from this patient was the near absence of dense bodies in his giant cells. Storage Pool Deficiency, together with large platelets, defective adhesion and aggregation of his macrocytes under shear stress to vWF and collagen and defective clot retraction may contribute to the pathogenesis of his bleeding disorder.

Background Differences in platelet counts are observed by use of automated haematology analyzers making interlaboratory comparison difficult. Materials and methods Twenty-eight single-donor platelet concentrates (PCs) were collected. Platelet concentration and markers of platelet destruction were investigated during storage for 11/12 days. Results Increasing impedance-immunoplatelet ratio was observed during storage, correlating to platelet fragments, large platelets, platelet density and cell-lysis. High variability was observed for optical-immunoplatelet ratio. Conclusion Immunoplatelet count or correction factor calculated by impedance-immunoplatelet ratio should be used to confirm that platelet unit meets platelet count requirements or to compare results from clinical trials. Optical platelet count is not recommended.

Kawasaki disease (KD) is a multisystem disorder of unknown origin and usually associated with thrombocytosis. The authors describe a case of KD exhibiting thrombocytopenia with markedly large platelets. Among the 173 KD cases, 3 cases exhibited thrombocytopenia. One of these showed cardiac involvement with giant aneurysm of the coronary artery (33%), while only 1 of the remaining 170 cases exhibited cardiac involvement without thrombocytopenia (0.6%). The authors believe that it is important for clinicians to be aware that thrombocytopenia may occur during the course of KD and that this may be a more active condition when compared with thrombocytosis.

Gray platelet syndrome (GPS) is an autosomal recessive bleeding disorder that is characterized by large platelets that lack α-granules. Here we show that mutations in NBEAL2 (neurobeachin-like 2), which encodes a BEACH/ARM/WD40 domain protein, cause GPS and that megakaryocytes and platelets from individuals with GPS express a unique combination of NBEAL2 transcripts. Proteomic analysis of sucrose-gradient subcellular fractions of platelets indicated that NBEAL2 localizes to the dense tubular system (endoplasmic reticulum) in platelets.

Abnormalities of platelet size are one of the distinguishing features of inherited thrombocytopenias (ITs), and evaluation of blood films is recommended as an essential step for differential diagnosis of these disorders. Nevertheless, what we presently know about this subject is derived mainly from anecdotal evidence. To improve knowledge in this field, we evaluated platelet size on blood films obtained from 376 patients with all 19 forms of IT identified so far and found that these conditions differ not only in mean platelet diameter, but also in platelet diameter distribution width and the percentage of platelets with increased or reduced diameters. On the basis of these findings, we propose a new classification of ITs according to platelet size. It distinguishes forms with giant platelets, with large platelets, with normal or slightly increased platelet size, and with normal or slightly decreased platelet size. We also measured platelet diameters in 87 patients with immune thrombocytopenia and identified cutoff values for mean platelet diameter and the percentage of platelets with increased or reduced size that have good diagnostic accuracy in differentiating ITs with giant platelets and with normal or slightly decreased platelet size from immune thrombocytopenia and all other forms of IT. Fil: Noris, Patrizia. University of Pavia; Italia Fil: Biino, Ginevra. Consiglio Nazionale Delle Ricerche. Istituto di Genetica Molecolare; Italia Fil: Pecci, Alessandro. University of Pavia; Italia Fil: Civaschi, Elisa. University of Pavia; Italia Fil: Savoia, Anna. Università degli Studi di Trieste; Italia. Istituto Di Ricovero e Cura a Carattere Scientifico Burlo Garofolo; Italia Fil: Seri, Marco. Università di Bologna; Italia Fil: Melazzini, Federica. University of Pavia; Italia Fil: Loffreddo, Giuseppe. Pausilipon Hospital; Italia Fil: Russo, Giovana. Università degli Studi di Catania; Italia Fil: Bozzi, Valeria. University of Pavia; Italia Fil: Notarangelo, Lucia Dora. Spedali Civili. Ospedale dei Bambini; Italia Fil: Gresele, Paolo. Università di Perugia; Italia Fil: Heller, Paula Graciela. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Médicas. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Médicas; Argentina Fil: Pujol Moix, Nuria. Universitat Autònoma de Barcelona; España Fil: Kunishima, Shinji. National Hospital Organization Nagoya Medical Center; Japón Fil: Cattaneo, Marco. Università degli Studi di Milano; Italia Fil: Bussel, James. Cornell University; Estados Unidos Fil: de Candia, Erica. Universita Cattolica del Sacro Cuore; Italia Fil: Cagioni, Claudia. University of Pavia; Italia Fil: Ramenghi, Ugo. Università di Torino; Italia Fil: Barozzi, Serena. University of Pavia; Italia Fil: Fabris, Fabrizio. Università di Padova; Italia Fil: Balduini, Carlo L.. University of Pavia; Italia

This paper describes the investigation into the effects of high intensity ultrasound opplied to the de-inking of toner-printed mixed recoverable office paper. Factors such as those of temperature and exposure time on paper pulps at neutral pH have been examined. It has been found that the large platelets of toner released during disintegration of the pulp can be reduced in a controlled manner to partide size ranges compatible with commercial deinking processes. It has also been established that toner detachment from fibre occurs predominantly with the attainment of smoller particle sizes. Temperature is found to have on important effect on both toner partide size reduction and the degree of toner-fibre detachment.

The principal physiological function of platelets is to promote haemostasis but they also contribute to thrombosis and atherogenesis. Platelet volume is a marker and possibly a determinant of platelet function in that large platelets are more active than normal sized platelets. Mean platelet volume (MPV), a measure of platelet size, reflects changes in either the level of platelet stimulation or the rate of platelet production. For these reasons, we have developed a sensitive instrument to measure platelet volume, which we believe is more reliable and specific than previously used instruments. It is based on a computer-interfaced Coulter Thrombocytometer and a pulse analyser including a high-speed baseline restorer. We have developed a reproducible method to assay MPV and from the histogram derived the median (MED) and the skewness (SK) values. We have looked at the effects of anticoagulant used and time elapse prior to assay. A normal range has been established for MPV which correlates directly with MED and inversely with SK. The MPV decreases with age but there is no difference between genders. We have demonstrated a negative correlation between whole blood platelet number and MPV and MED, and a direct relationship with the SK of the histogram of the platelet volume.

In September 2009 the European Society for Veterinary Clinical Pathology dedicated an entire day at the Congress of the European College of Veterinary Internal Medicine to discussing platelets. Platelets are small, anucleate cells that play a vital role in haemostasis. Clinical pathologists are familiar with the problems associated with counting platelets accurately. This is a particular problem in cats, in which platelets are easily activated and clump within the sample. Similarly, large platelets may be poorly distinguished from erythrocytes, especially by haematology analysers based on impedance methodology. Cavalier King Charles Spaniels (CKCS) (Fig. 1) with inherited macrothrombocytopaenia present a unique challenge to clinical pathologists and clinicians alike. Recently there have been research developments that may reveal the underlying pathogenesis of this condition and concurrently a focus on how platelet counts can be accurately achieved in these cases.

Precise counting of platelets is difficult particularly in the low thrombocytopenic range or when large platelets exist. The recently available Bayer ADVIA 120 analyser uses a method of counting platelets based on two dimensional laser light scatter. We have evaluated this technique on an analysis of 217 peripheral blood samples and found significant differences in platelet counts compared with values obtained by impedance technology, when the causes of thrombocytopenia were due to peripheral platelet consumption. Moreover, such differences were more marked in those samples from severely thrombocytopenic individuals with large platelets on the blood film. These differences, which warrant further study, may have significant implications for the management of patients with very low platelet counts.

[Figure][1] A 5-year-old girl was treated for 4 years based on a diagnosis of immune thrombocytopenia (ITP). When she presented for a second opinion, she met all criteria for ITP except that inspection of her peripheral blood smear showed large platelets with a complete lack of granulation