Behavioral control through the direct, focal silencing of neuronal activity.

The ability to optically stimulate and inhibit neurons has revolutionized neuroscience research. Here, we present a direct, potent, user-friendly chemical approach for optically silencing neurons. We have rendered saxitoxin (STX), a naturally occurring paralytic agent, transiently inert through chemical protection with a previously undisclosed nitrobenzyl-derived photocleavable group.

Planned Out-of-Hospital Birth as a Risk Factor for Nonreceipt of Hepatitis B Immunization.

Background: The hepatitis B vaccine (HBV) is recommended at birth to prevent perinatal hepatitis B transmission; however, many newborns still do not receive HBV. The extent to which planned out-of-hospital births, which have increased over the past decade, are associated with nonreceipt of the HBV birth dose is unknown. The purpose of this study was to determine whether a planned out-of-hospital birth location is associated with the nonreceipt of the HBV birth dose.

Precise spatiotemporal control of voltage-gated sodium channels by photocaged saxitoxin.

Here we report the pharmacologic blockade of voltage-gated sodium ion channels (Nas) by a synthetic saxitoxin derivative affixed to a photocleavable protecting group. We demonstrate that a functionalized saxitoxin (STX-eac) enables exquisite spatiotemporal control of Nas to interrupt action potentials in dissociated neurons and nerve fiber bundles. The photo-uncaged inhibitor (STX-ea) is a nanomolar potent, reversible binder of Nas.