In fasted and fed states, blood insulin levels are oscillatory. While this phenomenon is well studied at high glucose levels, comparatively little is known about its origin under basal conditions. We ...propose a possible mechanism for basal insulin oscillations based on oscillations in glycolysis, demonstrated using an established mathematical model. At high glucose, this is superseded by a calcium-dependent mechanism.
Abstract Patient registries are organized systems of data collection for scientific, clinical or health strategy purposes. Aims of our review were to document scientific literature based on data and ...information from cystic fibrosis (CF) registries; to understand which clinical problems have been addressed and for which of these the studies concerned have correctly answered the questions raised (i.e. a methodological critique) and to identify clinical issues in need of further investigation. The review included primary studies starting from a formally constituted CF registry of at least national level, using data from the registry to evaluate research hypotheses. This article is an overview of the research undertaken, focusing in detail on the issues of mortality and survival. The studies considered here focused mainly or secondarily on survival in CF, the aim being to ascertain an improving trend, identify any prognostic factors and, in some cases, attempt to provide a predictive model of survival.
A study was carried out on cord blood T cell activation via the CD2-mediated pathway. Despite similar percentages of circulating CD3+ and CD2+ cells in adult and cord blood, the proliferation of cord ...PBMC to the anti-CD3 mAb and cord T cells to anti-CD2 mAb were defective. The T cell CD3-surface structure was normally able to control CD2-mediated activation, as its modulation by a non-mitogenic anti-CD3 mAb blocked cord PBMC proliferation induced by anti-CD2 mAb. CD2-stimulated cord T cells did not proliferate and did not produce a significant amount of IL-2 in culture, although they expressed the IL-2R. This observation was confirmed by the optimal proliferation of CD2-induced cord T cells when rIL-2 was added. Despite the alternative T cell activation pathway is monocyte-independent in adults, the defective cord T cell activation via the CD2 molecule could also be bypassed by the addition of PMA, small amounts of either autologous or allogeneic adult and cord AC or simply rIL-1 alone. Our findings provide evidence for an intrinsic functional defect in cord CD2-mediated T cell activation, which is linked to an impaired increase of free cytoplasmic calcium, as confirmed by the effectiveness of calcium ionophore A23187 in restoring a good CD2-induced cord T cell proliferation and by measurement of cellular calcium uptake after activation via the CD2 molecule. The characteristics of cord T cells revealed by this study recall the thymocyte functional pattern and may represent functional expression of the previously described phenotypic immaturity of cord T cells.
A new case of Beemer short-rib dwarfism is reported and the clinical and radiological differences between this and Majewski type are discussed. The clinical variability related to the lack or ...presence of polydactyly is underlined, together with the importance of prenatal diagnosis.
The non-specific mitogen phytohaemagglutinin (PHA) and an anti-CD3 (OKT3) monoclonal antibody were used to measure the lymphocyte proliferative response in blood samples from 15 subjects with Down's ...syndrome. Blood from 15 healthy controls closely matched for age and sex was also assayed. The mean blastogenic value in PHA stimulated patient lymphocyte cultures was similar to that calculated in the controls. In contrast, the mitogenic response of lymphocytes from patients with Down's syndrome to anti-CD3 stimulation was on average significantly reduced. Immunofluorescence studies and additional experiments carried out by using semiallogeneic (maternal) monocytes as a source of antigen presenting cells showed that the impaired anti-CD3 induced mitogenesis in Down's syndrome could not be ascribed either to a lack of binding of the antibody to the trisomic cells, or to a defective monocyte-T cell interaction. These findings help to explain the cellular basis of the immune defect in Down's syndrome.
Peripheral blood mononuclear cells from 10 subjects with cytogenetically documented Down's syndrome (DS) and from 10 age- and sex-matched healthy controls were assayed for their ability to ...proliferate in response to phytohaemagglutinin, anti-CD3 (OKT3), or anti-CD2 (T11(2) plus T11(3 monoclonal antibodies. Interleukin 2 (IL-2) receptor expression and IL-2 production in mitogen-pulsed lymphocyte cultures was also investigated in parallel. DS cells responded poorly to all the blastogenic stimuli used in this study. Under certain experimental conditions (anti-CD3 or anti-CD2 antibody stimulation), the patients' lymphocytes expressed low levels of IL-2 surface receptors and failed to produce normal amounts of this lymphokine. Studies are currently in progress in our laboratories to determine whether these defects are due to an impairment of the early signalling events surrounding the complexing of CD3, CD2, or lectin receptors to their respective ligands.
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