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Cerebral ischemic stroke is a main cause of chronic disability. However, there is currently no effective treatment to promote recovery from stroke-induced neurological symptoms. Recent studies suggest that after stroke, immature neurons, referred to as neuroblasts, generated in a neurogenic niche, the ventricular-subventricular zone, migrate toward the injured area, where they differentiate into mature neurons. Interventions that increase the number of neuroblasts distributed at and around the lesion facilitate neuronal repair in rodent models for ischemic stroke, suggesting that promoting neuroblast migration in the post-stroke brain could improve efficient neuronal regeneration. To move toward the lesion, neuroblasts form chain-like aggregates and migrate along blood vessels, which are thought to increase their migration efficiency. However, the molecular mechanisms regulating these migration processes are largely unknown. Here we studied the role of beta 1-class integrins, transmembrane receptors for extracellular matrix proteins, in these migrating neuroblasts. We found that the neuroblast chain formation and blood vessel-guided migration critically depend on beta 1 integrin signaling. beta 1 integrin facilitated the adhesion of neuroblasts to laminin and the efficient translocation of their soma duringmigration. Moreover, artificial laminin-containing scaffolds promoted neuroblast chain formation and migration toward the injured area. These data suggest that laminin signaling via beta 1 integrin supports vasculature-guided neuronal migration to efficiently supply neuroblasts to injured areas. This study also highlights the importance of vascular scaffolds for cell migration in development and regeneration. (C) 2017 The Author(s). Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

Larval dispersion and recruitment of vent and seep animals are important to maintain species composition including endemic fauna. Rearing studies need enormous amounts of time, however, they produce much biological data. The larval data of vent and seep animals in this study will be important data for identification and larval dispersion. Many species of deep-sea chemosynthetic animals were collected and kept on board ships and in aquaria at atmospheric pressure. Larvae of several species of deep-sea chemosynthetic animals have been observed in aquaria: squat lobster Shinkaia crosnieri and Munidopsis myojinsinsis, vent crab Gandalfus yunohana, vent shrimp Opaepele loihi, vestimentiferan tube worms Lamellibrachia satsuma, Lamellibrachia sp. and Alaysia spp, vent and cold seep mussels Bathymodiolus platifrons and B. septenderium and vent flat fish Symphurus thermophilus. Embryonic development of several vent animals tends to be accelerated in higher temperatures. Such species larvae or eggs rise up to upper water layers by buoyancy or positive swimming. They may then be transferred to other habitats by ocean currents. Those larvae have eyes and may be active predators in the mid water, which is rich in prey and has higher temperatures than bottom layers. On the other hand, larvae or eggs of tube worms and mussels may be trapped in the circulation of water around their habitats and thus these larvae can acquire symbionts easily.