Protein carbonylation during natural leaf senescence in winter wheat, as probed by fluorescein-5-thiosemicarbazide.

Leaf senescence is characterised by a massive degradation of proteins in order to recycle nitrogen to other parts of the plant, such as younger leaves or developing grain/seed. Protein degradation during leaf senescence is a highly regulated process and it is suggested that proteins to be degraded are marked by an oxidative modification (carbonylation) that makes them more susceptible to proteolysis. However, there is as yet no evidence of an increase in protein carbonylation level during natural leaf senescence. The aim of our study was thus to monitor protein carbonylation level during the process of natural senescence in the flag leaf of field-grown winter wheat plants. For this purpose, we adapted a fluorescence-based method using fluorescein-5-thiosemicarbazide (FTC) as a probe for detecting protein carbonyl derivatives. As used for the first time on plant material, this method allowed the detection of both quantitative and qualitative modifications in protein carbonyl levels during the last stages of wheat flag leaf development. The method described herein represents a convenient, sensitive and reproducible alternative to the commonly used 2,4-dinitrophenylhydrazine (DNPH)-based method. In addition, our analysis revealed changes in protein carbonylation level during leaf development that were associated with qualitative changes in protein abundance and carbonylation profiles. In the senescing flag leaf, protein carbonylation increased concomitantly with a stimulation of endoproteolytic activity and a decrease in protein content, which supports the suggested relationship between protein oxidation and proteolysis during natural leaf senescence.

[Agyria-pachygyria and pachygyria in children. Contribution of imaging]. / Agyries-pachygyries et pachygyries de l'enfant. Apport de l'imagerie.

BACKGROUND: Lissencephaly (agyria-pachygyria) is a defect in migration of cerebral neurons resulting in failure of cortical gyri to develop. Progress in imaging techniques improves its diagnosis. POPULATION AND METHODS: The files of 17 patients (ten boys and seven girls), aged 7 months to 16 years, were retrospectively studied. The clinical picture consisted of mental retardation (17 patients), seizures (eight patients), facial dysmorphia (seven patients), axial hypotonia (four patients). CT scan was performed in 16 cases and MRI with T1 and T2 weighted images in all 17. RESULTS: The CT scan identified pachygyria in 12 cases. Cerebral calcifications were seen in four cases. MRI detected typical changes in all 17 cases: thickened cortex and gyri, loss of cortical white matter interdigitations, lack of operculisation of the sylvian fissure. Pachygyria was generalized (six patients) or localized (11 patients). Associated abnormalities were dysgenesis of corpus callosum in three patients, cerebellar hypoplasia in one, deep grey matter heterotopia in one; hypersignal of the white matter was identified on T2 weighted images in five patients. CONCLUSION: MR imaging permits precise analysis of abnormalities secondary to a defect in neuronal migration.

[Contribution of nuclear magnetic imaging in the diagnosis of Hallervorden-Spatz syndrome]. / Apport de l'imagerie en résonance magnétique nucléaire au diagnostic de syndrome d'Hallervorden-Spatz.

BACKGROUND: The manifestations of the Hallervorden-Spatz disease (HSD) usually appear during childhood or in adults. They are not specific and magnetic resonance imaging (MRI) has improved its diagnosis. CASE REPORT: A girl developed progressive motor difficulties, dystony, rigidity, spasticity and mental deterioration, beginning at the age of 18 months. Examination at the age of 13 years showed pigmentary degeneration of the retina and acanthocytosis. The CT scan showed symmetrical calcifications in both globus pallidus. The MRI showed heterogeneity of the globus pallidus, decreased signal intensity of magnetic resonance T2-weighted images with an aspect of "tiger eye". CONCLUSION: The MRI show peculiar signs that may help in the diagnosis of HSD, and eventually in genetic counselling.

Infantile myofibromatosis.

An unusual case of infantile myofibromatosis with foci of calcifications was presented, with atypical age of onset and location. The radiological features of this tumor are not always evocative, and histological examination is necessary for diagnosis.

Granulomatous hepatitis in pasteurella multocida infection.

Numerous diseases can lead to multilocular lesions of the liver. The authors report a rare pediatric case of hepatic granulomas due to Pasteurella multocida: a 7-year-old girl with chronic fever was investigated by sonography and CT scan, demonstrating mesenteric lymph node enlargement and numerous small hepatic lesions. After surgical biopsy, histopathology of the liver specimens showed pyogenic granuloma, with serologic testing positive for Pasteurella multocida. Treatment with a tetracycline and corticosteroids was successful. Pasteurella multocida infection, despite its habitual benign course, should be suspected among differential diagnoses of lymphogranulomatous affections with hepatic involvement. No case of liver and lymph node foci in a child has been previously described.

[Coffin-Lowry syndrome and hyperprolinemia]. / Syndrome de Coffin-Lowry et hyperprolinémie.

BACKGROUND: The main features of the Coffin-Lowry syndrome are mental retardation and features of a peculiar pugilistic nose, large ears, tapered fingers, drumstick terminal phalanges by X-rays and kyphoscoliosis. Inheritance is probably X-linked dominant. Its early diagnosis is difficult. CASE REPORT: A 31 month-old boy was admitted for mental retardation. His weight and height were normal, but his facies showed telecanthus, anteverted nares and a prominent frontal region. His hands appeared puffy with bulbous tapering fingers. Amino-acid chromatography showed hyperprolinemia (732 mumol/l) plus iminoglycinuria. His mother had a short stature, mental retardation and similar, although minor, manifestations of the Coffin-Lowry syndrome in her face, hands and fingers. She had moderate hyperprolinemia (391 mumol/l) without hyperglycinuria. The patient's father showed no physical abnormalities, but he also had hyperprolinemia (671 mumol/l) and hyperglycinuria. CONCLUSION: The association of the Coffin-Lowry syndrome and hyperprolinemia in this family seems fortuitous.