Science
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Two-way communication between neurons and nonneural cells called glia is essential for axonal conduction, synaptic transmission, and information processing and thus is required for normal functioning of the nervous system during development and throughout adult life. The signals between neurons and glia include ion fluxes, neurotransmitters, cell adhesion molecules, and specialized signaling molecules released from synaptic and nonsynaptic regions of the neuron. In contrast to the serial flow of information along chains of neurons, glia communicate with other glial cells through intracellular waves of calcium and via intercellular diffusion of chemical messengers. By releasing neurotransmitters and other extracellular signaling molecules, glia can affect neuronal excitability and synaptic transmission and perhaps coordinate activity across networks of neurons.
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The story of the renal transplant program of the Peter Bent Brigham Hospital (now the Brigham and Women's Hospital) in Boston weaves together three distinct threads: the study of renal disease, the phenomenon of skin grafting in twins, and the development of surgical procedures ultimately leading to the use of chemical immunosuppression. The common leitmotiv is one of a single event or report proving to be decisive. Unanticipated consequences of successful human organ transplantation include the reorganization of clinical and nonclinical disciplines, national and international cooperation in organ preservation and distribution, tissue-typing as a marker for disease, redefinition of death in terms of brain function, better understanding of disease processes, and new health care quandaries that result from the scarcity of organ donors.