Halved contrast medium dose coronary dual-layer CT-angiography - phantom study of tube current and patient characteristics.

Virtual mono-energetic images (VMI) using dual-layer computed tomography (DLCT) enable substantial contrast medium (CM) reductions. However, the combined impact of patient size, tube voltage, and heart rate (HR) on VMI of coronary CT angiography (CCTA) remains unknown. This phantom study aimed to assess VMI levels achieving comparable contrast-to-noise ratio (CNR) in CCTA at 50% CM dose across varying tube voltages, patient sizes, and HR, compared to the reference protocol (100% CM dose, conventional at 120 kVp).

The influence of motion-compensated reconstruction on coronary artery analysis for a dual-layer detector CT system: a dynamic phantom study.

Objectives: Cardiac motion artifacts hinder the assessment of coronary arteries in coronary computed tomography angiography (CCTA). We investigated the impact of motion compensation reconstruction (MCR) on motion artifacts in CCTA at various heart rates (HR) using a dynamic phantom.

Materials And Methods: An artificial hollow coronary artery (5-mm diameter lumen) filled with iodinated contrast agent (400 HU at 120 kVp), positioned centrally in an anthropomorphic chest phantom, was scanned using a dual-layer spectral detector CT.

Hepatic Arteriography and C-Arm CT-Guided Ablation (HepACAGA) to Improve Tumor Visualization, Navigation and Margin Confirmation in Percutaneous Liver Tumor Ablation.

Purpose: We present a technique that combines Hepatic Arteriography with C-arm CT-Guided Ablation (HepACAGA) to improve tumor visualization, navigation and margin confirmation for percutaneous ablation of liver tumors.

Materials And Methods: All consecutive patients scheduled for HepACAGA between April 20th, 2021, and November 2nd, 2021, were included in this retrospective, cohort study. HepACAGA was performed in an angiography-suite under general anesthesia.

[Radiologically inserted gastrostomy].

Radiologically inserted gastrostomy (RIG) is an alternative to percutaneous endoscopic gastrostomy (PEG) for patients with eating difficulties who need long-term enteral nutrition. This articles provides an overview of the technique of RIG as well as an analysis of the results of RIG at our institute over the last five years and a discussion of the literature. The number of centres in the Netherlands offering RIG is growing and therefore we want to raise awareness amongst colleagues who are not familiar with this alternative to PEG.

Expression of CD15 (FAL) on myeloid cells and chromosomal localization of the gene.

Different CD15 murine monoclonal antibodies were studied. These antibodies appeared to react specifically with the human myeloid-lineage-derived cell types in both peripheral blood and bone marrow. The antigens recognized by these antibodies were immunoprecipitated from lysates of 125I-labelled neutrophilic PMNs of healthy donors and subsequently analysed by electrophoresis on SDS-polyacrylamide gel and autoradiography.

Effective purging of bone marrow by a combination of immunorosette depletion and complement lysis.

The effectiveness of a simple immunorosette technique for the depletion of common acute lymphatic leukemic (cALL) blasts from autologous bone marrow transplants was studied. Erythrocytes were sensitized with tetramolecular complexes consisting of rat anti-mouse IgG1 monoclonal antibodies (McAbs) that crosslink two different mouse McAbs. One of the McAbs was directed against glycophorin A, and the other was directed against marker glycoproteins of B cells and their precursors (CD9, CD10, CD19, or CD22).

Biallelic neutrophil Na-antigen system is associated with a polymorphism on the phospho-inositol-linked Fc gamma receptor III (CD16).

Neutrophils express two distinct types of receptor for the Fc region of IgG, FcRII and FcRIII, in amounts of 10,000 to 20,000 FcRII (40 Kd) and 100,000 to 200,000 FcRIII (50 to 80 Kd) per neutrophil. We showed that the FcRIII exhibits genetically determined heterogeneity, detectable by differences in electrophoretic mobility with sodium dodecyl sulfate (SDS) as well as by reaction with antibodies against the biallelic neutrophil-specific antigen system NA. FcRIII was precipitated with an FcRIII-specific monoclonal antibody (MoAb) from the neutrophils of 35 donors.

Intracellular localization and de novo synthesis of FcRIII in human neutrophil granulocytes.

Immunoelectron microscopic studies in human neutrophils showed that FcRIII was present on the plasma membrane, in the Golgi complex, and in many small vesicles (120 to 180 nm). FcRIII was not found in specific or azurophilic granules as shown by immunogold double-labeling experiments, visualizing both FcRIII and either lactoferrin (a marker of specific granules) or myeloperoxidase (a marker for azurophilic granules). Because the occurrence of FcRIII in the Golgi complex suggested that biosynthesis of this receptor occurs in these cells, metabolic labeling experiments were performed.

Increased expression of leucocyte adherence-related glycoproteins by polymorphonuclear leucocytes during phagocytosis of staphylococci on an endothelial surface.

Phagocytosis of Staphylococcus aureus by human polymorphonuclear leucocytes (PMN) on the surface of endothelial cells is accompanied by adherence of the PMN to the endothelial surface and detachment of the endothelial cells from the culture monolayer. We studied the role of the leucocyte adherence-related glycoproteins (Leu-CAM: Mo1/LFA-1/150,95 or CD11a-c-CD18 complex) in these processes. Phagocytosis of S.

Binding characteristics of dimeric IgG subclass complexes to human neutrophils.

Immune complexes were prepared by incubation of human IgG paraproteins with F(ab')2 fragments of the mAb K35 against the kappa-L chain of human IgG. The composition of these complexes was analyzed by centrifugation over sucrose gradients, by gel filtration, by RIA with either IgG Sepharose or K35 Sepharose and by double-labeling studies. The results indicated that the complexes consist of saturated tetramers composed of two IgG molecules cross-linked by two F(ab')2 fragments of the mAb.

The 40-kDa Fc gamma receptor (FcRII) on human neutrophils is essential for the IgG-induced respiratory burst and IgG-induced phagocytosis.

Neutrophils express two types of receptor for the Fc region of IgG, FcRII and FcRIII. Per neutrophil, 10,000 to 20,000 molecules of FcRII (40 kDa) and 100,000 to 200,000 molecules of FcRIII (50 to 80 kDa) are expressed. Via these receptors, neutrophils bind IgG complexes that contain more than one IgG molecule.

In-vitro differentiation of cells of patients with acute undifferentiated leukaemia.

The diagnosis of acute undifferentiated leukaemia (AUL) is made when the cells of patients with acute leukaemias cannot be classified as myeloid or lymphoid by means of morphological, cytochemical and immunological criteria. The mononuclear cells of eight different AUL patients were cultured in suspension for 3 d with or without TPA. After culture, especially in the presence of TPA, the cells of all patients expressed at least one myeloid membrane antigen.

Binding of monoclonal antibody to CD16 causes calcium mobilization in large granular lymphocytes but inhibits NK killing.

A monoclonal antibody (mAb), CLB/FcR gran I, reactive with the CD16 Fc receptor (FcRlo/FcRIII) of human cells, leads to calcium mobilization in large granular lymphocytes (LGL) but not in granulocytes. Identical responses are obtained with F(ab')2 fragments of this antibody, indicating that the response is independent of Fc-FcR binding, and that bivalent cross-linking of this receptor is adequate for optimal calcium mobilization. The calcium response was greater in CD3- LGL compared to CD3+ LGL, although the response was augmented in the latter cells by prior rosetting with sheep red blood cells (SRBC).

Activation of cloned human natural killer cells via Fc gamma RIII.

The Fc gamma RIII (CD16) Ag on human NK cells involved in antibody-dependent cellular cytotoxicity has been demonstrated to be an important activation structure. The present studies were carried out to further characterize the functional role of the CD16 Ag and the mechanisms whereby cytotoxicity is activated by using human NK clones. In phenotypic studies Fc gamma RIII was found to be expressed heterogeneously on various human cloned NK cells.

Flow-cytometric detection of terminal deoxynucleotidyl transferase and other intracellular antigens in combination with membrane antigens in acute lymphatic leukemias.

Development of a new fixation procedure allowed flow-cytometric analysis of nuclear and other intracellular antigens in acute lymphatic leukemia (ALL). A short fixation of the cells with buffered formaldehyde acetone (BFA) rendered the cell membrane permeable, allowing the monoclonal antibodies (MoAbs) to penetrate the cell. Through this method, a rapid analysis of intracellular antigens, specific for acute lymphatic leukemia [such as terminal deoxynucleotidyl transferase (TdT), immunoglobulin M (IgM) heavy chain, and antigens recognized by the CD22 or CD3 MoAbs) was performed by flow cytometry.

The Fc valency of an immune complex is the decisive factor for binding to low-affinity Fc gamma receptors.

Tetanus toxoid (TT) was complexed with two human monoclonal antibodies. The antibodies recognized different, nonrepeating epitopes. The complexes formed were characterized by gel filtration and isokinetic sucrose density gradient centrifugation.

The PI-linked receptor FcRIII is released on stimulation of neutrophils.

Human phagocytic cells express receptors for the constant (Fc) region of immunoglobulin G. Neutrophils carry Fc receptor II (FcRII; CDw32) and FcRIII (CD16) which both bind IgG-containing immune complexes, leading to phagocytosis of the complex and activation of the neutrophil. We find that patients with paroxysmal nocturnal haemoglobinuria (PNH) have only about 10% of the normal levels of FcRIII on their neutrophils, whereas the expression of FcRII is unaffected.

Specific expression of a myeloid-associated CMP-NeuAc:Gal beta 1----3GalNAc alpha-R alpha 2----3-sialyltransferase and the sialyl-X determinant in myeloid human-mouse cell hybrids containing human chromosome 11.

Human-murine myeloid somatic cell hybrids were assayed for the expression of the myeloid-associated sialyl-X determinant. This determinant is expressed at the surface of hybrid cells containing human chromosome 11, but its expression could not be correlated with the presence of the sialyltransferase which is involved in the sialyl-X synthesis. The sialyl-X determinant, however, is simultaneously expressed with another alpha 2----3-sialyltransferase activity, which is involved in the sialylation of the O-linked Gal beta 1----3GalNAc alpha-R core structure.

A GDP-fucose:[Gal beta 1----4]GlcNAc alpha 1----3-fucosyltransferase activity is correlated with the presence of human chromosome 11 and the expression of the Lex, Ley, and sialyl-Lex antigens in human-mouse cell hybrids.

By fusion of human leukocytes and cells of the murine myeloid cell line WEHI-TG, we produced human-mouse myeloid cell hybrids. Hybrids which contain human chromosome 11 have been demonstrated to express the myeloid-associated carbohydrate antigen Lex (Geurts van Kessel, A. H.

Characterization of myeloid leukemia by monoclonal antibodies, with an emphasis on antibodies against myeloperoxidase.

Since the last workshop on human leukocyte differentiation antigens, there are 14 well defined cluster-designated (CD) antigens which characterize myelomonocytic cells. Of these, 5 are potentially useful for myeloid leukemia typing (i.e.

Neutrophil activation detected by monoclonal antibodies.

Monoclonal antibodies have been produced against three neutrophil-associated membrane proteins (p 90, p 170, and p 70) expressed at different maturation stages of the cells. The reactivity of the antibodies against p 90 (B13.9) and p 170 (CLB-gran 10), as measured by quantitative flow cytofluorometry, increased after stimulation of the neutrophils by the calcium ionophore A23187, by phorbol myristate acetate, or by the chemoattractant formylmethionyl-leucyl-phenylalanine in combination with cytochalasin B.

A murine monoclonal IgM antibody specific for blood group P antigen (globoside).

A murine monoclonal IgM erythrocyte antibody appeared to have anti-P (anti-globoside) specificity. The antibody was a relatively weak cold agglutinin, but a strong haemolysin and its reactivity with red cells was markedly enhanced by enzyme treatment. This antibody was used to study the cell and tissue distribution of globoside.