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Assesses the correlation between collagen lattice thickness and various collagen and cell concentrations by using B-scan echography. Importance of collagen; Materials and methodology of the study; Discussion on the results of the study.

An ultrastructural investigation of the organogenesis of the duck preen gland showed variations at the ecto-mesodermal interface in the course of development. During the period of invagination, ectoderm and mesoderm were separated by a continuous basal lamina. Morphogenesis of the tubules is characterized by a preferential deposition of non-oriented collagen fibres localized at the branching sites. Direct contacts between ectodermal extensions and mesodermal cells, through gaps in the basal lamina, appeared at the end-buds after the morphogenetic pattern was established and before the onset of the glandular secretory activity. The correlation between the modification of the ecto-mesodermal interface and the differentiation of uropygial ectoderm is discussed. [ABSTRACT FROM AUTHOR]

Abstract The genes coding for class I glutathione S-transferases in insects were believed to be intronless because the coding sequence was not interrupted by an intron. But sequences of the untranslated 5′ end of transcripts revealed the presence of an intron in housefly and Drosophila genes suggesting that most insect GSTI genes are in fact interrupted. [ABSTRACT FROM AUTHOR]

Bipolar lesion of the clavicle is rare. Only few cases have been reported. We report two cases treated surgically with success. In case of bipolar dislocation, surgical treatment guarantees better stability than conservative treatment. In case of fracture associated with sterno-clavicular dislocation, it is possible to stabilize both with the same Kirschner wire. Surgical treatment is recommended in young patients. [ABSTRACT FROM AUTHOR]

Studies were conducted between 1993 and 1996 using 3 natural grape vine populations, 1 susceptible laboratory strain, and 1 resistant selected strain of Drosophila melanogaster L. In vitro monooxygenase activity (ethoxycoumarine-O-deethylation) (ECOD) was recorded from microsomal fractions of all strains. Results varied over a 6-fold range between susceptible laboratory Canton and resistant selected RDDT strains and over a 2-fold range between the Canton strain and natural populations of flies. Few significant variations of ECOD activity were detected among the natural populations despite many insecticide treatments, but activities were significantly correlated with toxicological tolerance to 5 of the 15 insecticides (deltamethrin, fipronil, chlorpyriphos ethyl, DDT, and diazinon). Moreover, immunoblotting responsesof microsomal protein encoded by Cyp6A2 showed that the levels of expression were quantitatively correlated with toxicological tolerance to almost the same group of insecticides (deltamethrin, fipronil, chlorpyriphos ethyl, DDT, fenvalerate, and fenthion). However, the levelof CYP6A2 expression in some natural strains (still weakly resistant) was almost comparable with one of the resistant strains. In vivo monooxygenase activity recorded in individual abdomens of flies showed that frequency distributions of ECOD activity in natural populations overlapped those of the resistant and laboratory strains, which were much narrower. Substantial and fast frequency changes (of the narrowness) that obtained in laboratory were related to either the time of rearing of 1 of the natural populations or selecting this population with an insecticide that has a toxicology correlated with both of the monooxygenase signs measured. Perspectives on using the CYP6A2 expression and ECOD activity for detecting a resistance mechanism by cytochrome P450 in field populations are discussed. [ABSTRACT FROM AUTHOR]