[Benefits of a thickened infant formula with lactase activity in the management of benign digestive disorders in newborns]. / Intérêt d'une formule infantile épaissie avec activité lactasique dans la prise en charge des troubles digestifs bénins du nourrisson.

This study aimed at evaluating the interest of a thickened infant formula with lactase activity by comparison with a standard infant formula in the management of benign digestive disorders in infants. Infants of both sex (N =109), ranging in age from 0 to 3 months, were included in a randomised double blind trial. Infants went to the paediatrician because of benign digestive disorders such as regurgitation, eructation or hiccup, colic, persistent crying and/or meteorism. Nine hundred and three infants were included and randomised in two parallel groups: they consumed daily either the thickened infant formula with lactase activity or a standard infant formula. There were no significant difference in the infants included in both groups. Both formula were well accepted and tolerated. Growth of the infants and compliance during the study were identical and good in the two groups. The efficiency of the formula tested was showed on digestive symptoms through: a decrease of the intensity of the digestive discomforts more important in the test than in the standard formula group; a decrease of the intensity of the gaz significantly more important in the test than in the standard formula group; significant decreases in frequency and intensity of the gaz in the test group while there were no significant diminution in the standard group; This study showed the good tolerance, acceptability and efficiency of a thickened infant formula with lactase activity on benign digestive disorders of young infants.

The relationship between homozygous and hemizygous transgene expression levels over generations in populations of transgenic rice plants.

Segregating T(1), T(2) and T(3) transgenic rice populations, derived from independent particle-bombardment-mediated transformation events were examined in order to assess the effect of gene dosage on transgene expression levels and stability. The expression level of the unselected beta-glucuronidase ( gusA) reporter gene was quantified in plants from these populations. The gusA gene dosage was determined by segregation analysis of progeny seedlings at the structural level (by PCR) and at the expression level. For some transformation events a gene dosage effect on transgene expression was observed, leading to higher transgene expression levels in homozygous progeny than in hemizygous progeny or primary transgenic plants. However, in many other transformation events, the homozygous state appears to be disadvantageous, being associated with lower transgene expression levels, gene silencing or counter-selection of homozygous plants across generations. Change of gene dosage is probably one of the key factors influencing transgene expression levels and stability in transgenic rice. This is particularly important when considering molecular genetic studies and crop improvement programmes. The possible influence of matrix attachment regions (MARs) in increasing the likelihood of an additive effect on transgene expression level is discussed.