Sjogren-Larsson syndrome: 2 case reports

Sjogren-Larsson syndrome (SLS) is a neurocutaneous autosomal recessive disease caused by fatty aldehyde dehydrogenase (FADH) deficiency. This enzyme is involved in the biosynthesis pathways of some fatty acids, phytanic acid, and leukotrienes. The main features of the disease are its association with congenital ichthyosis, mental retardation, and spastic tetraplegia. Methods. We report on the diagnostic and therapeutic management of 2 cases of SLS. Results. The diagnosis of SLS was suspected in the first patient at 2 years of age before the clinical triad appeared and confirmed at 4 years of age by the culture of fibroblasts and the peak of lipids on 1.3 ppm spectroscopy. After 3 months of treatment with zileuton, an inhibitor of leukotriene synthesis, moderate clinical efficacy for pruritus and ichthyosis was observed. The second patient was diagnosed at 1 year of age with the association of psychomotor retardation and congenital ichthyosis, in accordance with acute Guillain-Barre syndrome. Diagnosis was confirmed with enzymology, and cerebral spectro-MRI featured an abnormal lipidic peak. Zileuton therapy was initiated at the time of diagnosis and was effective for pruritus after 6 months of treatment. Conclusion. We report 2 cases of SLS with delayed diagnosis, due to non neonatal symptoms. Treatment with zileuton shows partial efficacy especially in pruritus. The uncommon association of this rare dysmyelinating disease with Guillain-Barre syndrome in the second patient is discussed. (C) 2011 Elsevier Masson SAS. All rights reserve

A Microstructurally Based Model for Recrystallization in Dual-Phase Steels

International audienc

Influence of Heating Rate on Ferrite Recrystallization and Austenite Formation in Cold-Rolled Microalloyed Dual-Phase Steels

International audienc

Delaying Effect of Cementite on Recrystallization Kinetics of a Ti-Nb Microalloyed High-Formability Steel

International audienceAnnealing of cold-rolled high-strength steels leads to various microstructural changes such as recrystallization, cementite precipitation, microalloying elements precipitation and austenite formation. These transformations are expected to interact with each other. Understanding how and where austenite forms in a microstructure is of prime importance to avoid formation of banded microstructures, which are detrimental to good in-use properties. In this work, a mean-field model is used to simulate concomitant recrystallization, cementite precipitation, microalloying elements precipitation and austenite formation kinetics, as well as their interactions during 1 and 10 °C/s heating. Excellent agreement with experimental data is obtained only if cementite pinning effect on recrystallized grain boundaries is considered. It is shown that cementite exhibits a much stronger delaying effect on recrystallization kinetics than microalloying elements, leading to the formation of banded microstructures. Carbon nominal content of a steel appears to be the most important parameter to acknowledge to understand recrystallization kinetics