CHRONIC TRANSCRANIAL ELECTRICAL CONNECTOR

The device described in this proposal addresses the need identified by the NINDS for high-density percutaneous feedthroughs and implantable electrical connectors for neural prosthesis. The goal of the proposed research is to develop a chronic system for the transcranial delivery of signals and power to and from high density, multichannel electrode arrays implanted in mammalian sensory and motor cortexes. The concept is for a system consisting of a hermetic multilayer ceramic package that can house VLSI circuitry such as multiplexers, amplifiers and telemetry. It can be mounted either on top of, or in the plane of, the skull and connects to the electrode array with either a ribbon cable or a multiwire bundle, the ceramic package will also provide a means of connecting to the external environment; initially the system will use an electrical socket, mounted on the package, that protrudes from the scalp. VLSI multiplexing and pre- amplification circuitry in the hermetic ceramic package will allow the use of simple cable connectors, even for large arrays. The technology to be developed will ultimately provide the basis for interconnect systems to be used in human experimentation with neuroprosthetic applications. $ = TOTAL AWARD AMTS & NOT LIMITED TO PORTION OF PROJECT RELATED TO SUBJECT OF SEARCH SUBPROJECT $ = TOTAL AWARD AMOUNT DIVIDED BY NUMBER OF SUBPROJECTS SOURCE: CRISP FORMAT F FY 97 LAST UPDATE 04-07-98 1QUERY 1536 ID SEARCH 06/01/98 PAGE 499 --PROJECT NUMBER......1 R43 NS36490-01 INVESTIGATOR NAME/ADDRESS FY 97 RAUH, R DAVID IRG/INTRAMURAL UNIT..ZRG1 EIC LABORATORIES, INC AWARD AMOUNT......... $99,994 111 DOWNEY STREET NORWOOD, MA 02062 PERFORMING ORGANIZATION: EIC LABORATORIES, INC. TITLE INTEGRAL BIOSENSORS FOR NEUROCHEMICAL MONITORING ABSTRACT: A general concern in functional electrical stimulation (FES) is the changes in the extracellular microenvironment that accompany long-term electrical stimulation that can give rise to reversible and irreversible tissue damage and to neural dysfunction. In this program we will fabricate and evaluate a novel series of electrochemical biosensors for monitoring the chemical microenvironment during acute and chronic neural stimulation. These biosensors will employ electrochemical detection of the reaction products of analyte-specific enzymes incorporated in a hydrous oxide electrode matrix. They will be fabricated directly onto elements of electrode arrays currently employed in neural stimulation. These new tools will be valuable in neural prosthesis research for determining chemical imbalances which occur. Ultimately they will provide means of feedback control of artificial neural stimulation as long-lived, permanent additions to chronically implanted FES arrays. Phase I will demonstrate the feasibility of determining cerebrospinal fluid components (glucose, lactate, choline, glutamate, acetylcholine and urea) and demonstration of one or more sensors on an existing intracortical electrode array. Phase II will entail developing a wider range of improved biosensors for additional CSF components, design of optimal stimulation/biosensor microfabricated arrays, and in vivo studies of local extracellular chemistry during neural stimulation using the new microsensors. $ = TOTAL AWARD AMTS & NOT LIMITED TO PORTION OF PROJECT RELATED TO SUBJECT OF SEARCH SUBPROJECT $ = TOTAL AWARD AMOUNT DIVIDED BY NUMBER OF SUBPROJECTS SOURCE: CRISP FORMAT F FY 97 LAST UPDATE 04-07-98 1QUERY 1536 ID SEARCH 06/01/98 PAGE 500 --PROJECT NUMBER......1 R43 NS36499-01 INVESTIGATOR NAME/ADDRESS FY 97 ZHANG, ZHIYUAN IRG/INTRAMURAL UNIT..ZRG2 BIOWHITTAKER INC AWARD AMOUNT......... $96,285 8830 BIGGS FORD ROAD WALKERSVILLE, MD 21793 PERFORMING ORGANIZATION: BIOWHITTAKER, INC. TITLE OPTIMIZED CULTURE SYSTEMS FOR NORMAL HUMAN MICROGLIA ABSTRACT: The proposed research will develop the technology needed to supply commercially produced cultures of human microglia and specialized media for them to the biomedical research community. Microglia are the only type of immune cell found in the central nervous system in significant numbers. They are normally present in a quiescent state, but in response to injury or infection, they rapidly convert to ameboid macrophage-like cells that can release inflammatory cytokines and reactive oxygen species and are also capable of phagocytosis. Recent studies suggest that insufficiently regulated microglial responses may contribute to a variety of brain pathologies, including the neurodegeneration associated with Alzheimer's disease and the infectious spongioform encephalopathies, as well as delayed nerve loss after cerebral ischemia (stroke). Microglia are also the principal site for HIV infection in the brain, and are believed to be the cell type primarily responsible for HIV encephalitis. Phase I will determine the proliferative potential of normal human microglia and identify the best combinations of existing nutrient media and supplements for culturing them. During phase II, all components of the culture medium and other aspects of the culture system will be optimized and adapted as needed for commercial production. A reliable and consistent source of cultured human microglia will greatly facilitate future research on human brain function and pathology.