Dendritic spines appear and disappear in an experience-dependent manner. Although some new spines have been shown to contain synapses, little is known about the relationship between spine addition and synapse formation, the relative time course of these events, or whether they are coupled to de novo growth of axonal boutons. We imaged dendrites in barrel cortex of adult mice over 1 month, track...

Background Even though scoliosis is principally a deformity of the spine and the rib cage, some authors demonstrated that the pelvis can be included in the scoliotic process. Bernard Bricot concluded that the patients that presented with an excluded pelvis have a more evolving scoliosis. With regards to the pelvis we have two categories: the pelvis is excluded or included in the scoliotic proce...

Reports on reddish carotenoid-based ornaments in female three-spined sticklebacks (Gasterosteus aculeatus) are few, despite the large interest in the species' behaviour, ornamentation, morphology and evolution. We sampled sticklebacks from 17 sites in north-western Europe in this first extensive study on the occurrence of carotenoid-based female pelvic spines and throat ornaments. The field res...

Chick ciliary neurons have somatic spines grouped in discrete clumps or mats tightly folded against the soma and enriched in nicotinic receptors containing alpha7 subunits. An embryonic ciliary neuron has one to two dozen such spine mats, all overlaid by a large presynaptic calyx engulfing the cell. Three-dimensional tomographic reconstruction from serial thick sections revealed 13 somatic spin...

Long-term potentiation of synapse strength requires enlargement of dendritic spines on cerebral pyramidal neurons. Long-term depression is linked to spine shrinkage. Indeed, spines are dynamic structures: they form, change their shapes and volumes, or can disappear in the space of hours. Do all such changes result from synaptic activity, or do some changes result from intrinsic processes? How d...

Besides woody cone scales, certain species of wind-dispersed pines (Pinus) have spines on their scales as a putative form of defense against seed predators. We tested whether spines differentially deterred seed predators foraging on closed and open pine cones. Red Crossbills (Loxia curvirostra) were selected as the seed predator because they commonly forage on these cones. We timed crossbills f...

Dendritic spines are known to be extremely motile, providing a structural mechanism for synaptic plasticity. Actin filaments are thought to be responsible for the changes in the shape of spines. We tested our hypothesis that drebrin, an actin-binding protein, is a regulator of spine shape. In high-density long-term primary cultures of rat cerebral cortex neurons, drebrin was colocalized with ac...

The appearance and disappearance of dendritic spines, accompanied by synapse formation and elimination may underlie the experience-dependent reorganization of cortical circuits. The exact temporal relationship between spine and synapse formation in vivo remains unclear, as does the extent to which synapse formation enhances the stability of newly formed spines and whether transient spines produ...

The cellular and molecular mechanisms underlying the development and maintenance of dendritic spines are not fully understood. ADP-ribosylation factor 6 (ARF6) is a small GTPase known to regulate actin remodeling and membrane traffic. Here, we report involvement of ARF6 and exchange factor for ARF6 (EFA6A) in the regulation of spine development and maintenance. An active form of ARF6 promotes t...

The surface ultrastructure of Acanthotrema felis (Trematoda: Heterophyidae) adults, recovered from a kitten experimentally infected with the metacercariae, was observed using a scanning electron microscope. The worm was leaf-like, ventrally concave and covered with scale-like multi-pointed tegumental spines. The spines on the anterior surface were short but broad, and had 10-12 pointed tips. Th...