Publications by authors named "Beckman I"

Introduction: Sex differences in prenatal growth may contribute to sex-dependent programming effects on postnatal phenotype.

Methods: We integrated for the first time phenotypic, histomorphological, clinico-chemical, endocrine and gene expression analyses in a single species, the bovine conceptus at mid-gestation.

Results: We demonstrate that by mid-gestation, before the onset of accelerated growth, the female conceptus displays asymmetric lower growth compared to males.

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The purpose of this review is to survey, categorize, and compare the mechanical and thermal characteristics of fibers in order to assist designers with the selection of fibers for inclusion as reinforcing materials in the additive manufacturing process. The vast "family of fibers" is described with a Venn diagram to highlight natural, synthetic, organic, ceramic, and mineral categories. This review explores the history and practical uses of particular fiber types and explains fiber production methods in general terms.

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Evaluation of several versions of phenomenological theory of gas permeability in selective polymeric membranes is presented, along with the appropriate experimental methods for verification of these versions. The main focus is on a description of stationary mass transfer across membranes (films) containing dispersion inclusions of various shapes of one polymer in a matrix of another. Considering heterogeneous media as a membrane material, it was assumed that diffusion and sorption properties of inclusions are different from those of the dispersing medium.

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Parent-of-origin-dependent (epi)genetic factors are important determinants of prenatal development that program adult phenotype. However, data on magnitude and specificity of maternal and paternal genome effects on fetal bone are lacking. We used an outbred bovine model to dissect and quantify effects of parental genomes, fetal sex, and nongenetic maternal effects on the fetal skeleton and analyzed phenotypic and molecular relationships between fetal muscle and bone.

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Rhabdomyosarcomas are soft-tissue tumors, rare in adults. Accounting for nearly 5% of childhood cancers, they represent less than 0.03% of adult malignancies (1, 2).

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Laparoscopic marsupialization of lymphocele carries 13% recurrence rate, 6% injury to other organs, 12% omentoplasty, 6% open conversion and 1.8 average hospital days. A novel, simplified technique of intraperitoneal catheter drainage of lymphocele is described.

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Certain immunological activities, particularly cell-mediated immunity, decline with advancing age. Gaining insight into the underlying mechanism(s) is complicated by the fact that human T-cells comprise several functionally and phenotypically distinct populations and subpopulations. Proliferative studies designed to identify differences between old and young subjects that are based entirely on unfractionated peripheral blood lymphocytes (PBLs) or pan T-cell responses run the risk, therefore, of missing subtle but perhaps crucial changes in a particular T-cell type.

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CD44 is a widely distributed cell surface glycoprotein that participates in a number of cellular adhesion and signal transduction processes. Germinal center B cells express very low levels of CD44, whereas their precursors and differentiation products express much higher levels. In immunofluorescence studies comparing 20 antibodies classified as being against the hematopoietic isoform of CD44, one antibody, A1G3, was unreactive with germinal center B cells, whereas the other antibodies showed low intensity but definite reactivity.

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Aged persons frequently manifest declining parameters of those immune functions which protect the young against disease. Longitudinal studies are beginning to show that number, type and function of T cells may be associated with longevity, morbidity and mortality in free-living elderly humans. Multi-faceted alterations in the ability of T cells from old donors to respond to stimulation are being dissected, and pathways which are compromized in the elderly compared to the young are being defined.

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Despite the presence of a lymphocytic infiltrate in solid cancers, the failure for tumour growth to be contained suggests an inadequate immune response to the tumour. Poor cytotoxicity exerted by tumour-infiltrating lymphocytes (TILs) against tumour cells in vitro, combined with continued tumour growth in vivo, suggests deficiencies in TIL function or numbers. Various theories have been postulated to explain how tumour cells may escape immunosurveillance and control.

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The growth characteristics in vitro of interleukin 2 (IL 2)-dependent human CD4+ alpha beta-T cell receptor-positive helper T cell clones (TCC) were studied in relation to alterations in surface phenotype, cytokine responsiveness, and susceptibility to activation-induced cell death (AICD). TCC derived from peripheral blood T cells had finite lifespans averaging 33 population doublings (PD) with a recorded maximum lifespan of 80 PD (n = 208). First analyses of the TCC were undertaken at ca.

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Integrated non-porous membrane systems were applied for microbial combustible gas separation processes. Methane/CO2 mixtures of various concentrations from methane fermentation processes (biogas) were separated using a membrane-separation complex of permabsorber type into individual components of technical grade (more than 95% purity). In experiments with three-component mixtures, using a selective membrane valve with various liquid carriers, all the gases of interest (H2, CH4 and CO2) were obtained at greater than 90% purity in one separation step.

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Spiral computed tomography (CT) performed during arterial portography offers several advantages compared with portographic studies based on conventional CT technique. Because all hepatic images are derived from a volume data set acquired during a single 24-32-second breath hold timed to coincide with the phase of peak hepatic enhancement, motion artifacts and section misregistration are eliminated and high liver-to-lesion attenuation value differences are present on all sections. These factors, in conjunction with the ability to retrospectively acquire thin, overlapping axial sections, result in improved lesion detection.

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It is well documented that the proliferative capacity of T cells declines with advancing age. There are, however, conflicting data as to the role of the accessory cell and whether or not this loss in responsiveness extends to all T-cell stimuli and to all T cells. We report here on the capacity of subpopulations of peripheral blood CD4+ T cells from the healthy aged to proliferate in response to anti-CD2 receptor-induced activation in the complete absence of accessory cells by using various exogenous cofactors as second signals.

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Transcranial Doppler sonography can be used to evaluate a spectrum of intracranial and extracranial vascular abnormalities. It is of proved value in the detection and follow-up of vasoconstriction caused by subarachnoid hemorrhage and can be used to demonstrate significant stenosis or occlusion of basal intracranial arteries and coexisting routes of collateral circulation. Transcranial Doppler sonography can play an important role in the determination of brain death and can be used to identify the nidus of an arteriovenous malformation, along with its major routes of supply and drainage.

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Transcranial Doppler sonography is a noninvasive technique that uses a 2-MHz, pulsed Doppler transducer to measure the velocity of blood flow within the circle of Willis and vertebrobasilar system through regions of temporal calvarial thinning or through the orbits or foramen magnum. By using spectral analysis of the Doppler frequency shifts from insonated red blood cells moving through a preselected arterial sample volume, transcranial Doppler calculates and displays the peak systolic and diastolic velocity, the mean velocity, and the pulsatility index of blood flow within the interrogated vessel. Vessel identification is based on standard criteria, including the cranial window used, transducer position, depth of sample volume, direction of blood flow, relationship to the terminal internal carotid artery, and response to common carotid artery compression.

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Cytokines have been postulated to play important roles in tumour biology and in the host response to tumours, and a number of therapeutic modalities involving cytokines have been proposed. If patients are to be treated with cytokines, or cytokine inhibitors, it will be important to determine the potential for direct action of the cytokine on the tumour cells. In this study, a high-sensitivity immunofluorescence technique is used to determine the expression of a number of cytokine receptors on a total of 115 leukaemic samples.

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Cytokine mRNA expression was analyzed by reverse transcriptase (RT)/PCR in extensively purified normal peripheral CD4+CD45R T cell subsets. Both CD45RA+ and CD45 RO+ populations produced mRNAs for interleukin (IL)-2, IL-2 receptor (alpha chain), IL-6 receptor and tumour necrosis factor (TNF)-beta within 3-4 h of activation. Whilst IL-3 and RANTES were also expressed in both subsets, CD45RO+ cells were clearly the major producers of these cytokines.

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Vascular damage, initiated by host inflammatory cells, is a component of the pathophysiology of many acute and chronic inflammatory disorders. Neutrophil-mediated tissue damage is mediated primarily by proteinases, particularly elastase and cathepsin G. In this study we have identified endothelial binding of two key serine proteinase inhibitors (serpins), alpha 1-antitrypsin, the inhibitor of elastase, and alpha 1-antichymotrypsin, the inhibitor of cathepsin G.

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This study used a panel of mAb and multiparameter flow cytometry to assess the composition of PBL from healthy aged individuals. The results showed that while total lymphocyte numbers altered only marginally in the aged (> or = 70 years) there were significant changes in the distribution of various sub-populations; for example, there were lower numbers of CD3+ and CD8+ cells, and higher numbers of CD16+ (NK) cells. As a direct result of these changes the numbers of CD2+ cells remained unchanged in the aged compared with young adult controls (18-25 years).

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T cell responsiveness to in vitro stimulation is severely diminished in the aged. Recent studies would suggest that this may be due, at least in part, to a reduction in interleukin 2 (IL-2) secretion and high-affinity IL-2 receptor (HA-IL-2R) expression. In this report we confirm and extend these studies to show that the fall in IL-2 production is not due to reduced numbers of IL-2 mRNA producing T cells but rather to a decline in the relative amount of IL-2 mRNA expressed per cell.

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A case of silent extraperitoneal rectal perforation secondary to colonoscopic polypectomy is presented. Computed tomography (CT) demonstrated pathways of gas diffusion from the perirectal site to different compartments of the retroperitoneum, to the mediastinum and peritoneum.

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The role of accessory cells (AC) in the temporal expression of several key T-cell-activation-associated antigens has been studied in healthy aged subjects. Compared to responses seen in young adults, phytohaemagglutinin (PHA) induced weak proliferation in peripheral blood mononuclear cells from the aged and lower numbers of T cells expressing CD71, CD25, CD38 or HLA-DR. T cell responses to the monoclonal antibody OKT3, however, were normal.

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In this report, we describe a 76-kDa glycoprotein recognized by mAb FMC46 that, by virtue of its concentration on cell protrusions involved in motility, may be important in lymphoid cell locomotion. FMC46 detects an epitope of the leukocyte adhesion molecule-1 (LAM-1), a member of the selecting family (LAM-1, Endothelial Leukocyte Adhesion Molecular-1 (ELAM-1), and Granule Membrane Protein-140 (GMP-140), that is expressed on LAM-1-transfected cell lines, is a glycosylation epitope based on its loss after culture in tunicamycin, and is closely related to the LAM-1.2 epitope.

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