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High VEGFCmRNA expression of acute myeloid leukemia (AML) blasts is related to increased in vitro and in vivo drug resistance. Prognostic significance of VEGFCon long-term outcome and its associated gene expression profiles remain to be defined. We studied effect of VEGFCon treatment outcome and investigated gene expression profiles associated with VEGFCusing microarray data of 525 adult and 100 pediatric patients with AML. High VEGFCexpression appeared strongly associated with reduced complete remission rate (P= .004), reduced overall and event-free survival (OS and EFS) in adult AML (P= .002 and P< .001, respectively). Multivariable analysis established high VEGFCas prognostic indicator independent of cytogenetic risk, FLT3-ITD, NPM1, CEBPA, age, and white blood cell count (P= .038 for OS; P= .006 for EFS). Also, in pediatric AML high VEGFCwas related to reduced OS (P= .041). A unique series of differentially expressed genes was identified that distinguished AML with high VEGFCfrom AML with low VEGFC, that is, 331 up-regulated genes (representative of proliferation, vascular endothelial growth factor receptor activity, signal transduction) and 44 down-regulated genes (eg, related to apoptosis) consistent with a role in enhanced chemoresistance. In conclusion, high VEGFCpredicts adverse long-term prognosis and provides prognostic information in addition to well-known prognostic factors.

High VEGFC mRNA expression of acute myeloid leukemia (AML) blasts is related to increased in vitro and in vivo drug resistance. Prognostic significance of VEGFC on long-term outcome and its associated gene expression profiles remain to be defined. We studied effect of VEGFC on treatment outcome and investigated gene expression profiles associated with VEGFC using microarray data of 525 adult and 100 pediatric patients with AML. High VEGFC expression appeared strongly associated with reduced complete remission rate (P = .004), reduced overall and event-free survival (OS and EFS) in adult AML (P = .002 and P < .001, respectively). Multivariable analysis established high VEGFC as prognostic indicator independent of cytogenetic risk, FLT3-ITD, NPM1, CEBPA, age, and white blood cell count (P = .038 for OS; P = .006 for EFS). Also, in pediatric AML high VEGFC was related to reduced OS (P = .041). A unique series of differentially expressed genes was identified that distinguished AML with high VEGFC from AML with low VEGFC, that is, 331 up-regulated genes (representative of proliferation, vascular endothelial growth factor receptor activity, signal transduction) and 44 down-regulated genes (eg, related to apoptosis) consistent with a role in enhanced chemoresistance. In conclusion, high VEGFC predicts adverse long-term prognosis and provides prognostic information in addition to well-known prognostic factors.

Transparent film materials with excellent mechanical and thermal properties were elaborated by drying a latex suspension of armored polymer/Laponite composite particles. Low‐temperature TEM observation of ultrathin cross‐sections of the films indicated a unique network morphology characterized by a “honeycomb” distribution of the Laponite platelets remindful of the original particles morphology.

Locatelli: Jazz Pharmaceeutical: Speakers Bureau; Medac: Speakers Bureau; Miltenyi: Speakers Bureau; Bellicum Pharmaceutical: Membership on an entity's Board of Directors or advisory committees; Novartis: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Amgen: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau. Niemeyer:Celgene: Consultancy; Novartis: Consultancy.

Neurofibromatosis type 1 (NF-1) predisposes to juvenile myelomonocytic leukemia (JMML) via loss of function of the NF1tumor suppressor gene and consecutive deregulation of Ras signal transduction. Affected individuals usually carry one defective NF1allele in the germline; somatic inactivation of the second NF1allele in hematopoietic cells is associated with transformation to leukemia. We previously demonstrated that a major mechanism for biallelic loss of NF1function in patients with JMML/NF-1 is mitotic recombination leading to uniparental disomy (UPD) of the 17q chromosome arm (Flotho, 2007; Steinemann, 2010). Using contemporary resequencing and microarray technology, we have now revisited the genetics of NF1inactivation in JMML. Specifically, we addressed two questions: 1) Are genetic findings in leukemic cells of JMML/NF-1 patients consistent with the clinical diagnosis and the two-hit concept? 2) Does the quintuple-negative (QN) group of JMML (patients without clinical evidence of NF-1 and negative for mutations in PTPN11, KRAS, NRAS, or CBL) contain unrecognized cases likely driven by NF1?

Background Between 1994 and 2005, seven patients underwent surgery at the Foothills Medical Centre, Calgary, Alberta, for injuries sustained in bear maulings. The purpose of the present study was to document these cases and add to the literature on the management and the potential complications of bear attacks.Methods Data were collected retrospectively from charts.Results Seven patients were treated for injuries ranging from lacerations and puncture wounds to fractures and avulsed tissue. On average, patients underwent three operations and spent 22 days in hospital. Mean time from attack to arrival at the trauma centre was 19 h. Irrigation, debridement and intravenous antibiotics did not prevent wound infections in two patients. Six of seven patients developed acute stress disorder, and one of these patients went on to suffer from post-traumatic stress disorder. Complications ranged from infection to pulmonary embolism.Conclusions Bear attacks result in a spectrum of injuries. Infections and psychiatric disorders are common sequelae.

The molecular basis of almost all red cell and platelet blood group antigens is known. This enables the prediction of red cell or platelet phenotypes based upon the genotypes. In many laboratories, blood group genotyping assays are routinely used in cases where patient red cells cannot be used for serological typing due to the presence of autoantibodies (direct antiglobulin test (DAT)-positive) or after recent transfusion. Furthermore, fetal genotyping is routinely performed where there is a risk of alloimmune-mediated red cell or platelet destruction. In the Netherlands, medium-throughput human platelet antigen (HPA) genotyping has been introduced in the blood banks to guarantee direct (on-shelf) availability of HPA-1a- and HPA-5b-negative platelets for newborns suffering from neonatal alloimmune thrombocytopenia. The techniques used, pyrosequencing and Taq- Man-based allele-specific hybridization assay, are discussed in this review. Recently, several research groups investigated whether red cell molecular typing could also be introduced for large-scale blood donor typing to obtain and maintain an inventory of typed (antigen-negative) donors. The reason for this is that phenotyping of large cohorts of donors is a labor-intensive exercise and hampered by the lack of sufficient amounts of approved typing reagents for all blood group systems of interest. Several approaches for high-throughput genotyping, based on DNA microarrays spotted on glass slides or beads, have now been tested and are also discussed in this review.

The two key parameters for levitation performance over a permanent magnet (PM) guideway are the levitation force and the stiffness of the high temperature superconductor (HTS) YBaCuO bulk. Their distributions along a lateral displacement (LD) were measured in zero-field-cooling (ZFC) and in field-cooling (FC) conditions. There are two cases of applied magnetic field for a single HTS bulk: symmetrical or unsymmetrical about the bulk axis. Although the levitation force has a linear relationship with the applied field in the symmetrical case, such a linear relationship disappears once the applied field becomes unsymmetrical. Furthermore, the levitation stiffness is measured in FC, and they still change more drastically than the levitation force in ZFC. In particular, the levitation stiffness has a linear relationship with the associated levitation force, whether the applied field is symmetrical or unsymmetrical. Its lateral distribution at a gap of 20 mm in FC agrees with the levitation force distribution at a gap of 10 mm in ZFC.

A kinetic study was carried out on the regio- and stereoselectivities of 12 lipases of animal and microbial origin. For this purpose, monomolecular films consisting of three pairs of enantiomers (didecanoyl-deoxyamino-O methyl glycerol, DDG) containing a single hydrolyzable decanoyl ester bond and two lipase-resistant groups were spread at the air–water interface. Each of the lipases tested displayed a particular type of behavior, on the basis of which they were classified in two groups, depending on their ability to hydrolyze the sn-2 position. From the qualitative point of view, the sn-2 preference measured on triacylglycerides and DDG were in good agreement. The inductive chemical effect might explain why a greater level of hydrolytic activity was observed with the diglycerides than with DDG. With most of the lipases tested, it was observed that the enantiomeric pair having two distal acyl chains was more clearly differentiated stereochemically than the two homologous pairs with two adjacent acyl chains. This finding is consistent with the hypothesis that during the chiral recognition process two of the three attachment points may be the external (distal) hydrophobic chains, which is in line with the hypothesis of a tuning fork conformation of a triglyceride in the lipase active site. Chirality 15:220–226, 2003. © 2003 Wiley-Liss, Inc.

The magnetic domain structure in Permalloy (Ni₈₁Fe₁₉) micropatterns (10–100 μm) on NiO has been investigated by means of soft x-ray photoemission electron microscopy. The exchange anisotropy between the Ni₈₁Fe₁₉ patterns and the NiO layer results in the formation of complex domain structures which markedly differ from the simple Landau–Lifshitz configurations. The domain structures reflect the competition between the exchange anisotropy and the dipole–dipole interaction in a weakly coupled system. The observed domain structures change with the feature size, as the domain patterns lose complexity in the smaller structures.

BACKGROUND: Neutrophil antigen 5b has been described as involved in transfusion reactions and not in neonatal alloimmune neutropenia. CASE REPORT: Anti-5b was found in the serum of a mother of a persistently neutropenic newborn, who had several bacterial infections. The neutropenia responded to treatment with recombinant human granulocyte-colony-stimulating factor. Immunoprecipitation experiments performed with this and three other 5b antisera identified a protein, migrating from 70 to 95 kDa, as carrier of 5b. The observed pattern of migration may point to heavy glycosylation of this protein. RESULTS: Six 5b-negative donors were identified among 54 screened white donors, for a 5b gene frequency of 0.66. CONCLUSION: Alloimmunization to 5b in pregnancy is rare. In the patients with neonatal neutropenia analyzed in the last decade, this was the first case discovered.

Background

A two-dose mass vaccination programme with a combined vaccine against measles, mumps and rubella (MMR) was adopted in the Netherlands in 1987, replacing the selective schoolgirl vaccination strategy introduced in 1974. To obtain insight into the effect of mass vaccination and the population's immunity, the antibody levels against rubella were studied in the general Dutch population and in religious groups refusing vaccination. In the national sample, we observed a high prevalence (96·5%) for rubella antibodies in vaccinated cohorts as well as in the older unvaccinated cohorts. No indications of rapidly waning immunity after vaccination were found. There are indications of low virus circulation in the last few years. The very high seroprevalence in women at childbearing age is consistent with the few reported cases of congenital rubella syndrome (CRS) at present. However, individuals in the age group of 1–9 years who are not vaccinated for religious or other reasons have a considerably lower seroprevalence and thus there is a potential risk of a CRS outbreak in the future.

In this paper, after recalling the main features of the NA57 experiment, we describe its silicon pixel tracker.

The charged particle multiplicity distributions measured with the WA97 and the NA57 multiplicity detectors in Pb+Pb collisions at 158 A GeV/ c have been analyzed in the framework of the Wounded Nucleon Model (WNM). We obtain a good description of the data within the centrality range of our samples. This allows us to make use of the measured multiplicities to estimate the number of wounded nucleons of the collision.

Background: 5-Aminosalicylic acid (5-ASA) is widely used as topical treatment in patients with distal inflammatory bowel disease. The enema spread and retention time are considered to be important factors in the efficacy of this therapeutic agent. Whereas colonic spread is widely investigated in selected patient populations and volunteers, much less attention has been given to the in vitro differences of physical and chemical properties, although they may influence the in vivo characteristics.

A frozen-hydrated specimen of the hexagonal bilayer hemoglobin (HBL Hb) from the deep-sea hydrothermal vent polychaete wormAlvinella pompejana, the most thermophilic metazoan known to date, was observed in the electron microscope and subjected to three-dimensional (3D) reconstruction by the method of random conical tilt series. At a resolution of 34.6 Å by the differential phase residual method and 27.7 Å by the Fourier shell correlation method, the 3D volume possesses a D₆point-group symmetry. While in previous 3D reconstructions of annelid and vestimentiferan Hbs the vertices of the upper layer were 16° rotated compared with those of the lower layer, inAlvinellaHb the vertices of the two hexagonal layers are almost perfectly eclipsed when viewed along the 6-fold axis. As in the HBL Hbs ofRiftia pachyptilaandMacrobdella decora, a central linker complex is decorated by 12 hollow globular substructures (HGS). The linker complex comprises (1) a central hexagonal toroid, (2) two internal bracelets onto which the HGSs are built, and (3) six connections between the two hexagonal layers. Each HGS is composed of six masses, which are separated when the volume is displayed at high threshold, plus one additional mass involved in the bracelet connecting the six HGSs in both hexagonal layers. The HGSs have a local pseudo 3-fold symmetry and a disposition of the high-density masses different from those ofRiftiaV1 Hb.

In four healthy volunteers, we analyzed in detail the immediate in vivo effects on circulating neutrophils of subcutaneous administration of 300 µg of granulocyte colony-stimulating factor (G-CSF). Neutrophil activation was assessed by measurement of degranulation. Mobilization of secretory vesicles was shown by a decrease in leukocyte alkaline phosphatase content of the circulating neutrophils. Furthermore, shortly postinjection, FcγRMI was found to be upregulated from an intracellular pool that we identified by immunoelectron microscopy as secretory vesicles. Intravascular release of specific granules was shown by increased plasma levels of lactoferrin and by upregulation of the expression of CD66b and CD11b on circulating neutrophils. Moreover, measurement of fourfold elevated plasma levels of elastase, bound to its physiologic inhibitor α1-antitrypsin, indicated mobilization of azurophil granules. However, no expression of CD63, a marker of azurophil granules, was observed on circulating neutrophils. G-CSF—induced mobilization of secretory vesicles and specific granules could be mimicked in whole blood cultures in vitro, in contrast to release of azurophil granules. Therefore, we postulate that the most activated neutrophils leave the circulation, as observed shortly postinjection, and undergo subsequent stimulation in the endothelial microenvironment, resulting in mobilization of azurophil granules. Our data demonstrate that G-CSF should be regarded as a potent immediate activator of neutrophils in vivo.

Neutrophils from patients with paroxysmal nocturnal hemoglobinuria (PNH) show a deficiency for the glycosylphos-phatidylinositol- (GPI) linked Fcγ receptor IIIb (FcγRIIIb, CD16). The functional consequences of this defect are not clear. Here, we examined FcγRIIIb-deficient neutrophils for their activation via Fcγ receptors. Hydrogen peroxide (H2O2) production and change of intracellular free calcium [Ca2+]iwere used as parameters for cell activation. FcγRII and FcγRIIIb stimulation was reached by cross-linking using fragments of monoclonal antibodies or incubation with monoclonal IgG cryoglobulin complexes. In parallel to the deficiency of FcγRIIIb expression, H2O2production and [Ca2+]iinflux were decreased after cross-linking of FcγRIIIb in PNH neutrophils compared with that for normal neutrophils. Stimulation via FcγRII was not affected. Cryoglobulin complexes previously shown to activate normal neutrophils predominantly via FcγRIIIb stimulated PNH neutrophils at a level not significantly weaker than controls. But this activation was mediated only via FcγRII as shown by blocking studies. The results suggest that the loss of GPI-anchored FcγRIIIb is functionally replaced by FcγRII during the immune complex stimulation of PNH neutrophils. Therefore, the equipment of neutrophils with pleomorphic Fcγ receptors prevents an immunodeficiency in PNH.

Preamplifiers, computer-controlled main amplifiers and trigger electronics have been designed and built for our charged particle multidetector system (MDS). These electronic process signals from the individual detection elements of the MDS, each consisting of a silicon surface-barrier detector and a CsI(Tl) scintillator with photodiode readout. Our design is compact, reliable, cheap, and well-suited for the multidetector system.

The chlorocruorin of the polychaeteEudistylia vancouveriiobserved in the electron microscope in vitreous ice, was subjected to a three-dimensional (3D) reconstruction by the random conical tilt series method. The 3D volume with a resolution of 35 Å reconstructed from 1062 images in top, side and intermediate view orientations has a D₆point-group symmetry. It possesses the characteristic hexagonal bilayer (HBL) appearance. Each hexagonal half-molecule comprises size hollow globular substructures (HGS) presumed to correspond to the dodecameric subunits. In projection, when the molecule is viewed along its 6-fold axis, the two halves are not perfectly eclipsed. The vertices of the upper hexagonal layer are 14° rotated clockwise compared with those of the lower half. At a threshold displaying 100% of the expected molecular volume, the 3D volume contains in its center a flat hexagonal central mass disconnected from the rest of the volume. Several types of connections, termed c1 through c4, are visible between the HGSs. The c1 and c2 connections link the HGSs of the same hexagonal half-molecule. The c3 connections make a hexagonal inner bracelet linking the HGSs of each half-molecule. The c4 connections link pairs of HGSs superposed in the two hexagonal layers. Because of the half-molecules rotation around the 6-fold axis, the two HGSs linked by a c4 connection are not exactly superposed. It is proposed that the c3 and c4-connection bodies and less probably the flat central hexagonal mass are composed of chloroheme-deficient linker chains. When eroding the 3D volume by raising the threshold, the HGS appears composed of three elongated structures likely containing four globin chains. In addition, they show an approximate 3-fold symmetry. At high thresholds, two of these masses, dumbbell-shaped, separate into globular masses while the third structure remains compact as long as 1% of the molecular volume is displayed.

We performed a detailed kinetic study on the in vivo effect of a single subcutaneous dose of granulocyte colony-stimulating factor (G-CSF; 300 µg) in four healthy individuals on the expression and function of neutrophil Fcγreceptors (FcγR). G-CSF did not induce FC7RI (CD64) on circulating neutrophils. However, neutrophils newly formed in response to G-CSF were FcγRI positive and were able to perform antibody-dependent cellular cytotoxicity in an FcγRI-dependent way. FcγRII (CD32) expression was not changed significantly. FcγRIII (CD16, phosphatidylinositol-linked) expression, slightly increased immediately (30 minutes) postinjection, was found to be strongly decreased on the newly formed population. For comparison, we studied the expression of the PI-linked proteins leukocyte alkaline phosphatase (LAP) and CD14. Intracellular levels of LAP mirrored the biphasic expression pattern as membrane-bound FcγRIII. In contrast, CD14 expression on neutrophils was initially constant, followed by high levels on the newly formed neutrophils. Soluble CD14 levels were found to be elevated transiently, whereas peak levels of soluble FCγIII were observed as late as 6 days postinjection. In conclusion, we have shown that G-CSF results in an immunophenotypically and functionally altered neutrophil population for an important part as a result of its effect on myeloid precursor cells.