Anesthetic loss of consciousness induced by chemogenetic excitation of mesopontine effector neurons.

Although general anesthesia is normally induced by systemic dosing, an anesthetic state can be induced in rodents by microinjecting minute quantities of GABAergic agents into the brainstem mesopontine tegmental anesthesia area (MPTA). Correspondingly, lesions to the MPTA render rats relatively insensitive to standard anesthetic doses delivered systemically. Using a chemogenetic approach we have identified and characterized a small subpopulation of neurons restricted to the MPTA which, when excited, render the animal anesthetic by sensorimotor (immobility) and electroencephalographic (EEG) criteria.

A composite hip implant.

Composites are made of two or more different components that combine their properties into a new material. By modifying the type or structure or volume of the components, a theoretically endless number of new materials can be produced and their properties can be altered as desired. A composite hip implant made of carbon fiber and polysulfone is described.