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Transcription of the D. melanogaster Fat-body-protein-1 (Fbp1) gene is induced by the steroid hormone 20-hydroxyecdysone and is restricted to the fat body tissue at the end of the third larval instar. The location and functional properties of the Fbp1 cis-acting regulatory sequences contained in the region from -1386 to +80 relative to the transcription start were examined by transformation using hybrid constructs with the Adh or lacZ genes as reporters. Regulatory element(s) required for the full level of transcription of the Fbp1 gene were located between positions -1386 and -138. Sequences between -138 and -68 were able to drive transcription from a heterologous minimal promoter in the fat body of late third instar larvae. Remarkably, these sequences also conferred 20-hydroxyecdysone inducibility and behaved as an enhancer-like element. These results provide the first functional characterization, at the level of the whole organism, using a direct in vivo ecdysone induction assay, of a discrete ecdysone response element.

Principles of dietary management and needs in maple syrup urine disease are well defined. However, long-term results show that there is a need for an improvement of the maintenance of a low plasma leucine level and in monitoring episodes of metabolic decompensation in order to ameliorate the survival and psycho-intellectual outcome.

Antitumoral effects and intratumoral concentrations of a metalloporphyrin were studied in mice with solid chemo-induced or transplanted tumors. The synthesis of this molecule was realised both with a stable metal (TPPS4SnCl2) (TPPS4InCl) and a radioactive metal (TPPS4(113)SnCl2) (TPPS4(111)InCl). The metal is introduced into the tetrapyrollic structure to give this molecule very high stability. The effect of the stable metalloporphyrin on tumoral kinetic parameters was analyzed. No tumoral regression was observed during the various experimental procedures. Even though radioactive molecules were found in the tumours, they were also present as high concentrations in the liver, spleen and kidneys, more than 72 hours after injection. Results are compared with those of various authors who used a molecule without metal, levels being measured by fluorescence in various organs and in the tumors. The interest of this metalled molecule in carcinology is discussed in relation to these new results.