Experimental Model for the Study of Reparative Bone Regeneration in the Reconstruction of the Lower Jaw.

An experimental in vivo model has been developed on the rabbit mandible to study reparative regeneration of alveolar bone after intercortical split osteotomy and the role of the periosteum in the process of reparative osteogenesis. The peculiarity of this model is fixation of the periosteum over the reconstruction zone, which allows preserving the bone block displaced during surgery and leads to the formation of an organotypic structure of the regenerate with cortical and spongy bone.

[Role of auxin in induction of polarity in zygotes of Fucus vesiculosus L].

We studied the effects of auxin (indolyl-3 acetic acid) on formation of the primary polarity axis in zygotes of the brown algae Fucus vesiculosus. Within the first 2.5 h after fertilization, the zygotes release this phytohormone in the environment.

[Electro-osmotic phenomena in plant tissues].

The effect of a direct electric current on electrolyte transport through plant tissues was studied by applying it to 10-mm fragments of the mesocotyls of etiolated maize seedlings, similar fragments of one-year linden shoots with the normal conducting system and without vascular bundles, and isolated elements of the xylem and cell wall segments. At the current density and voltage of 9-38 microA/mm2 and 10-20 V, electrolyte solutions in plant tissues always moved toward the cathode. The results suggest that electroosmosis is one of the factors responsible for changes in solution transport through the conducting plant tissues that occur under the effect of electric current.

Influence of serotonin on calcium transport in rat liver mitochondria.

It was shown in experiments in vitro that serotonin, depending on the concentration, has different effects on calcium transport in rat liver mitochondria. In a concentration of 10(-6) M it increases the ability of the mitochondria to bind calcium; in a higher concentration (10(-4) M) serotonin accelerates the release of calcium from the mitochondria. The effect of serotonin is detected at a calcium concentration in sucrose medium of the order of 10(-4) M and is not observed when the mitochondria are incubated in a complete reaction medium.