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The processes of flat bones growth, sutures formation and interdigitation in the human calvaria are controlled by a complex interaction between genetic, biochemical and environmental factors that regulate bone formation and resorption during prenatal development and infancy. Despite previous experimental evidence accounting for the role of the main biochemical factors acting on these processes, the underlying mechanisms controlling them are still unknown. Therefore, we propose a mathematical model of the processes of flat bone and suture formation, taking into account several biological events. First, we model the growth of the flat bones and the formation of sutures and fontanels as a reaction diffusion system between two proteins: TGF-β2 and TGF-β3. The former is expressed by osteoblasts and allows adjacent mesenchymal cells differentiation on the bone fronts of each flat bone. The latter is expressed by mesenchymal cells at the sutures and inhibits their differentiation into osteoblasts at the bone fronts. Suture interdigitation is modelled using a system of reaction diffusion equations that develops spatio-temporal patterns of bone formation and resorption by means of two molecules (Wnt and Sclerostin) which control mesenchymal cells differentiation into osteoblasts at these sites. The results of the computer simulations predict flat bone growth from ossification centers, sutures and fontanels formation as well as bone formation and resorption events along the sutures, giving rise to interdigitated patterns. These stages were modelled and solved by the finite elements method. The simulation results agree with the morphological characteristics of calvarial bones and sutures throughout human prenatal development and infancy., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

This paper describes an enzyme immunoassay for the quantitative determination of IgG, IgA, and IgM immunoglobulins on RBCs. Ether eluates made from RBCs were followed by an enzyme-linked immunosorbent assay of immunoglobulin concentration. Calibration curves were derived from immunoglobulin standards and the number of molecules of each isotype per RBC was calculated. The assay was carried out in 200 healthy blood donors and 62 patients with warm autoimmune hemolytic anemia (AIHA), two of them with a negative DAT. For healthy blood donors, mean values were 58 IgG, 16 IgA, and 3 IgM molecules per RBC. For patients with a positive DAT, the mean values were 3435 IgG, 157 IgA, and 69 IgM molecules per RBC. An increased level of IgA was found in 12 patients without IgA autoantibodies demonstrable in RBC eluates. Increased IgG levels were also observed in patients with a negative DAT and, in one case, an increased level of IgA was also found. The enzyme-linked immunosorbent assay using ether eluates is a sensitive method for quantitating RBC autoantibodies in patients with AIHA as well as immunoglobulins bound to RBCs in healthy individuals.

Normal platelets display a log normal size distribution pattern when analysed by an automated cell counter. Considerable changes in the platelet size distribution occurs during collection, processing and storage. This is easily monitored by the variation seen in the cellular indices or size distribution patterns. Platelet activation leads to a shift to the right whereas discoid/spheric conversion and microvesiculation/fragmentation are associated to shift to the left. Therefore changes in cellular indices are of value in assessing the dynamic shape changes and aggregation/disaggregation that platelet undergo during storage. We describe here an objective method for measuring platelet functional integrity based on cell counting. Our procedure is simple and based on the measurement of difference (d) of MPV before and after the addition of platelet samples to EDTA (4 ml dry dipotassium EDTA tube), incubating at 22 degrees C for a period of 1 h (for optimisation of shape changes and disaggregation) before counting. Since the platelet functional activity/aggregation states are pH-dependent we have investigated the effect of buffering condition on the functional integrity measured by dMPV. Both the standard and buffered EDTA exposure procedures appear to be suited for monitoring platelet functional integrity/aggregation and activation states but the standard EDTA protocol eliminates the need for pH determination hence is our preferred diagnostic tool, for platelet functional integrity and aggregation states.