Thermographie synchrone pulsée:application à la caractérisation énergétique d'un laser de puissance.

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Germ-line mutation analysis in patients with multiple endocrine neoplasia type 1 and related disorders.

Multiple endocrine neoplasia type 1 (MEN1) is an autosomal dominant syndrome predisposing to tumors of the parathyroid, endocrine pancreas, anterior pituitary, adrenal glands, and diffuse neuroendocrine tissues. The MEN1 gene has been assigned, by linkage analysis and loss of heterozygosity, to chromosome 11q13 and recently has been identified by positional cloning. In this study, a total of 84 families and/or isolated patients with either MEN1 or MEN1-related inherited endocrine tumors were screened for MEN1 germ-line mutations, by heteroduplex and sequence analysis of the MEN1 gene-coding region and untranslated exon 1. Germ-line MEN1 alterations were identified in 47/54 (87%) MEN1 families, in 9/11 (82%) isolated MEN1 patients, and in only 6/19 (31.5%) atypical MEN1-related inherited cases. We characterized 52 distinct mutations in a total of 62 MEN1 germ-line alterations. Thirty-five of the 52 mutations were frameshifts and nonsense mutations predicted to encode for a truncated MEN1 protein. We identified eight missense mutations and five in-frame deletions over the entire coding sequence. Six mutations were observed more than once in familial MEN1. Haplotype analysis in families with identical mutations indicate that these occurrences reflected mainly independent mutational events. No MEN1 germ-line mutations were found in 7/54 (13%) MEN1 families, in 2/11 (18%) isolated MEN1 cases, in 13/19 (68. 5%) MEN1-related cases, and in a kindred with familial isolated hyperparathyroidism. Two hundred twenty gene carriers (167 affected and 53 unaffected) were identified. No evidence of genotype-phenotype correlation was found. Age-related penetrance was estimated to be >95% at age >30 years. Our results add to the diversity of MEN1 germ-line mutations and provide new tools in genetic screening of MEN1 and clinically related cases

Mechanisms of metal-phosphates formation in the rhizosphere soils of pea and tomato: environmental and sanitary consequences

International audiencePurpose At the global scale, soil contamination with persistent metals such as lead (Pb), zinc (Zn), and copper (Cu) induces a serious threat of entering the human food chain. In the recent past, different natural and synthetic compounds have been used to immobilizemetals in soil environments. However, the mechanisms involved in amendment-induced immobilization of metals in soil remained unclear. The objective of the present work was therefore to determine the mechanisms involved in metal-phosphates formation in the rhizospheric soils of pea and tomato currently cultivated in kitchen gardens. Materials and methods Pea and tomato were cultivated on a soil polluted by past industrial activities with Pb and Zn under two kinds of phosphate (P) amendments: (1) solid hydroxyapatite and (2) KH2PO4. The nature and quantities of metal-P formed in the rhizospheric soils were studied by using the selective chemical extractions and employing the combination of X-ray fluorescence micro-spectroscopy, scanning electron microscopy, and electron microprobe methods. Moreover, the influence of soil pH and organic acids excreted by plant roots on metal-P complexes formation was studied. Results and discussion Our results demonstrated that P amendments have no effect on metal-P complex formation in the absence of plants. But, in the presence of plants, P amendments cause Pb and Zn immobilization by forming metal-P complexes. Higher amounts of metal-P were formed in the pea rhizosphere compared to the tomato rhizosphere and in the case of soluble P compared to the solid amendment. The increase in soil-metal contact time enhanced metal-P formation. Conclusions The different forms of metal-P formed for the different plants under two kinds of P amendments indicate that several mechanisms are involved in metal immobilization. Metal-P complex formation in the contaminated soil depends on the type of P amendment added, duration of soil-plant contact, type of plant species, and excretion of organic acids by the plant roots in the rhizosphere