A multi-channel bioluminescent bacterial biosensor for the on-line detection of metals and toxicity. Part II: technical development and proof of concept of the biosensor.

This research study deals with the on-line detection of heavy metals and toxicity within the context of environmental pollution monitoring. It describes the construction and the proof of concept of a multi-channel bioluminescent bacterial biosensor in immobilized phase: Lumisens3. This new versatile device, designed for the non-stop analysis of water pollution, enables the insertion of any bioluminescent strains (inducible or constitutive), immobilized in a multi-well removable card.

Alkaline phosphatase activity in the theca of ovarian follicles of the hen throughout follicular development.

Within the hen's ovary, the theca tissue of small follicles that have not yet entered the preovulatory hierarchy is a major contributor to ovarian steroidogenesis. Relatively little is known about developmental stages in the theca layer within this pool of follicles and of the histological properties of this tissue. In pigs and sheep, alkaline phosphatase activity has been identified in the theca of preovulatory follicles and in theca-derived cells in the corpus luteum.

Effects of increased dietary energy after mating on developmental uniformity and survival of porcine conceptuses.

Two experiments were conducted to examine the effect of the feeding of a high-energy diet during early gestation on survival of porcine conceptuses. In the first, 91 second-estrus gilts were inseminated 24 h after detection of standing estrus and randomly assigned to a recommended energy (RE: 22.2 MJ of DE/d) or high-energy diet (HE: 36.

Elevated endometrial natural killer cell activity during early porcine pregnancy is conceptus-mediated.

This study investigated an extended time course of endometrial NK cell activity during gestation and the mechanisms underlying changes in uterine NK cell activity in pigs. Endometrial tissues were collected from cyclic, pseudopregnant and pregnant nulliparous pigs on various days post-estrus, and from pigs 10 days after insemination with seminal plasma or killed spermatozoa. NK effector cells were isolated from each endometrial sample, size fractionated and tested for cytolytic activity against NK target cells (K562) using chromium release assays and immunocytochemically for the frequency of perforin-positive cells.

Structure-function relationships during preovulatory development of porcine follicles following equine chorionic gonadotropin stimulation.

Porcine follicular maturation begins by recruitment from a continually proliferating pool of small antral follicles; those receiving the appropriate stimulus differentiate rapidly through a series of structural and functional changes. Such ovarian activity can be induced in prepubertal gilts with a single injection of equine chorionic gonadotropin (eCG). Average follicular diameter in eCG treated females increased from approximately 2 mm before stimulation to 3.