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F Albert

Publications and source records attributed to F Albert.

61 records · Page 4Linked to original sources

Early steps of lymphocyte activation bypassed by synergy between calcium ionophores and phorbol ester.

Although it has been proposed that the activation of T lymphocytes is mediated by an early rise in cytosolic calcium concentration, it has not been possible to mimic antigen- or mitogen-induced mouse lymphocyte activation by calcium ionophores that bypass receptor-mediated processes. There is now evidence from other systems that the rise in cytosolic calcium which follows receptor triggering is preceded by the breakdown of phosphatidylinositol bisphosphate into 1,2-diacylglycerol and inositol trisphosphate. The latter is known to cause release of calcium from intracellular stores. The cellular target for the former is now widely accepted to be protein kinase C. Therefore, ligand-induced cellular response follows a rise in cytosolic calcium concentration and protein kinase C activation. Here we confirm that the calcium ionophores A23187 and ionomycin do not activate mouse T lymphocytes. However, either one in combination with the phorbol ester 12-O-tetradecanoylphorbol 13-acetate (TPA), which is structurally related to 1,2-diacylglycerol, induces in lymphoid cell populations the expression of receptors for interleukin-2 (IL-2), the secretion of IL-2 and cell proliferation as measured by 3H-thymidine uptake. The growth-promoting effect of IL-2 on an exogenous IL-2-dependent clone could not be substituted for by ionomycin either alone or with TPA. Thus, the combination of calcium ionophores and TPA bypasses the requirement for antigen- or lectin-induced signal at the onset of lymphocyte activation.

Animals↗

[Subacute sclerosing panencephalitis (SSPE) as differential diagnosis in severe personality changes and ataxia--case report and literature review].

An 8 year old girl presented with progressive change of personality and spastic ataxia since 4 weeks. A year before she had developed focal grand-mal-seizures; at this time laboratory and radiologic findings were normal. The EEG on admission demonstrated marked changes with partially focal, partially generalized hypersynchronic activity, but no SSPE-typical Radermecker-complexes. There were no cells in the cerebrospinal fluid (CSF), a slightly increased level of protein and a normal glucose. Isoelectric focusing showed predominantly measles-specific oligoclonal IgG bands in the CSF. In the magnetic resonance tomography multiple focal white matter lesions in the basal ganglia as well as in cortical and occipitoparietal regions could be seen. At the age of two the girl had suffered from measles, the child didn't receive any vaccination. The combination of history, CSF-, MRI-results and EEG lead to the diagnosis of subacute sclerosing panencephalitis (SSPE). After 3 months the clinical and radiological abnormalities had markedly increased. On the background of this history SSPE should be considered as differential diagnosis in patients with changes of personality.

Cerebrospinal Fluid Proteins↗

Cine MRI of mitral regurgitation in planes angled along the intrinsic cardiac axes.

OBJECTIVE: This prospective study was designed to evaluate the mechanism and severity of mitral regurgitation (MRG) by means of cine MRI using planes angled along the intrinsic cardiac axes. MATERIALS AND METHODS: In 25 patients with MRG, analysis of the direction, extent, and distribution of left atrial signal void area was performed on both two chamber and four chamber cine MRI views. Cine MRI features including qualitative grading, maximal length of regurgitant jet, and ratio of regurgitant jet area to left atrial area were compared with the results of color flow Doppler (CFD) mapping (n = 25), angiography (n = 20), and regurgitant fraction as determined at catheterization (n = 15). RESULTS: In the four chamber view, cine MRI demonstrated central extension of regurgitant jet (n = 8) in cases with dilatation of valve annulus or retraction of both mitral valve leaflets, anterior extension (n = 8) in cases with prolapse of the posterior leaflet, and posterior extension (n = 7) in cases with prolapse of the anterior leaflet or retraction of the posterior leaflet. In two cases of mild MRG with small signal void area, evaluation of mechanism was not feasible. The results of cine MRI and angiographic qualitative gradings were the same in 19 of the 20 patients and differed by one grade in the other patient. In the 25 patients, maximal length of the regurgitant jet was well correlated with both regurgitant jet area and ratio of the jet area to the left atrial area as determined by CFD mapping (r = 0.91, r = 0.85, p < 0.0001, respectively). In 15 patients the maximal length of regurgitant jet was correctly correlated with regurgitant fraction determined at catheterization (r = 0.76, p < 0.001). CONCLUSION: Cine MRI by means of planes angled along the intrinsic cardiac axes allows assessment of both the mechanism and the severity of MRG.

Adult↗

[Cranial traumatism following a fall in children under 4 years of age (author's transl)].

This survey was carried out on 706 cases chosen at random, of cranial traumatism following a fall in children under 4; it underlines the fact that in most cases there is a favourable evolution. However, complications may always occur, even in apparently slight accidents. A clinical examination, although difficult to carry out, reveals important information for the detection and treatment of complications, which are mainly intracranial collections which are not always immediately detectable; this entails a constant observation for at least one week. Complementary tests give information which must be interpreted according to clinical situation.

Accidents↗