The dopamine receptor antagonist haloperidol disrupts behavioral responses of sea urchins and sea stars.

Despite lacking a brain and having an apparent symmetrically pentaradial nervous system, echinoderms are capable of complex, coordinated directional behavioral responses to different sensory stimuli. However, very little is known about the molecular and cellular mechanisms underlying these behaviors. In many animals, dopaminergic systems play key roles in motivating and coordinating behavior, and although the dopamine receptor antagonist haloperidol has been shown to inhibit the righting response of the sea urchin Strongylocentrotus purpuratus, it is not known whether this is specific to this behavior, in this species, or whether dopaminergic systems are needed in general for echinoderm behaviors. We found that haloperidol inhibited multiple different behavioral responses in three different echinoderm species. Haloperidol inhibited the righting response of the sea urchin Lytechinus variegatus and of the sea star Luidia clathrata. It additionally inhibited the lantern reflex of S. purpuratus, the shell covering response of L. variegatus and the immersion response of L. variegatus, but not S. purpuratus or L. clathrata. Our results suggest that dopamine is needed for the neural processing and coordination of multiple different behavioral responses in a variety of different echinoderm species.

Lessons learned from an elementary school norovirus outbreak.

Outbreaks of norovirus have been on the increase. The virus often spreads quickly through schools and similar institutions. The school nurse may be able to minimize the impact of a school norovirus outbreak by providing accurate information about the disease, the scope of the local situation, and instruction on infection control measures. This article describes a norovirus outbreak experienced by an elementary school in which 41% of students were afflicted. The experience of the school nurse managing the outbreak is examined, and recommendations are offered for use by other school nurses facing similar outbreaks to reduce the spread and impact of the virus. Often the very measures that school personnel instinctively employ, such as the increased use of hand sanitizers and systematic use of disinfecting agents that are actually ineffective against norovirus, can have the opposite of the intended effect and inadvertently further the spread of the disease.