1985 — 1990 |
Mcdonald, John W |
T32Activity Code Description: To enable institutions to make National Research Service Awards to individuals selected by them for predoctoral and postdoctoral research training in specified shortage areas. |
Principles in Pulmonary Research |
1 |
1985 — 1993 |
Mcdonald, John W |
R01Activity Code Description: To support a discrete, specified, circumscribed project to be performed by the named investigator(s) in an area representing his or her specific interest and competencies. |
Fibronectins Role in Pericellular Matrix Organization
Based on our previous and ongoing studies, fibronectin (FN) - a multifunctional dimeric glycoprotein in plasma, basal lamina, and connective tissue matrices - participates in host defense, maintenance of lung architecture, and collagen deposition. These multiple biologic roles are possible by virtue of FN binding via specific sites or domains to other structural macromolecules, to itself, and to receptor armed cells. While this general scheme is well established, the cellular and molecular basis of FN's interactions with cells and with connective tissue components is not presently understood, but is critical for elucidating FN's role in lung structure and function. We have developed and applied new methods over the past three years, including a library of domain specific anti-FN antibodies and fragments with defined biologic activity, as well as biochemical and morphologic techniques to critically evaluate the basis of FN's interactions with cells and organization of connective tissue matrices. These methods will now be applied to the following specific aims: 1) The role of FN in supramolecular organization and deposition of other pericellular matrix components, including collagen and glycosaminoglycans in fibroblast culture. 2) The mechanisms of pericellular matrix organization in fibroblast cultures. 3) The interaction of FN with cells in two contrasting models: the human alveolar macrophage, and cultured lung fibroblasts, using antibodies to the FN cell receptor and heterologous mixing experiments to determine the requirements for extracellular matrix formation by FN secreting cells. Together, our studies will lead to new knowledge and tools fundamental to understanding the basis of FN's biological activities, and help to clearly delineate FN's role in lung and other organ structure and function. This information will provide a rational basis for diagnostic and ultimately theraputic intervention in lung and other diseases characterized by abnormal organization of connective tissue matrices. A promising first step in this direction is our ability to inhibit collagen deposition in lung fibroblast cultures by selective inhibition of FN matrix formation.
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1 |
1987 — 1991 |
Mcdonald, John W |
R01Activity Code Description: To support a discrete, specified, circumscribed project to be performed by the named investigator(s) in an area representing his or her specific interest and competencies. |
Growth Factors and the Fibroproliferative Lung Diseases
We have found that the lungs of patients with active pulmonary fibrosis contain connective tissue cells reacting with monoclonal antibodies directed against the carboxylterminal propeptide domain of type I collagen, although healthy lungs lacked these cells entirely. We have also found that this altered phenotype which is characteristic of fibroblasts in embryonic or healing wounds, is reproduced in the dermis following injection of pure transforming growth factor-beta (TGF-beta). Thus, pulmonary fibrosis is associated with the proliferation of connective tissue synthesizing cells - "fibroblasts" - as well as with alterations in the collagen synthesizing phenotype of fibroblasts. We propose to test the hypothesis that certain "growth factors", such as TGF- beta and platelet derived growth factor are responsible for expanding the fibroblast population and modulating their phenotype by increasing the expression of fibronectin and collagen at sites of lung injury. We will also try to determine whether there are subpopulations of lung fibroblasts which may respond differently to these mediators in vivo. We will use sensitive immunohistologic, biochemical and molecular biologic methods to examine the effects of these "growth factors" on fibroblast differentiation. Monoclonal antibodies to type I procollagen and other connective tissue molecules, as well as nucleic acid probes for fibronectin and the interstitial and basement membrane collagens and growth factors will be employed. These methods should allow us to assess the connective tissue synthesizing phenotype of individual human lung fibroblasts in intact tissues and cell culture, and provide evidence for their origins. Studies of intact tissues are always difficult, but are ultimately essential for understanding the complex cellular and molecular events associated with the response of cells to injury in vivo. In vitro studies of cell populations usually obscure cellular heterogeneity and provide no more than an average assessment of differentiated function. By contrast, the approaches outlined in this application should permit a direct assessment of cellular differentiation and lung fibroblast heterogeneity with respect to their most fundamental function, i.e. the synthesis and deposition of extracellular matrix.
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1 |
1991 — 1995 |
Mcdonald, John Stuetzle, Werner (co-PI) [⬀] Derose, Anthony |
N/AActivity Code Description: No activity code was retrieved: click on the grant title for more information |
Mathematical Sciences: Curve and Surface Reconstruction Fromunorganized Data @ University of Washington
Scientists and engineers often encounter data in the form of a relatively dense collection of points on or near the surface of the object of interest; and one objective is to reconstruct the surface of the object. Examples come from medical imaging, machine vision, industrial engineering, statistical analysis for high-dimensions, and geometric modelling. This research will develop algorithms for such problems when neither the topology nor the geometry of the surface are known a priori; both must be inferred in automated fashion from the data points.
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0.915 |
1992 — 1996 |
Mcdonald, John Stuetzle, Werner [⬀] |
N/AActivity Code Description: No activity code was retrieved: click on the grant title for more information |
Mathematical Sciences: Data Visualization Using Focusing Andlinking @ University of Washington
To display complicated information, a common instinct is to draw a picture that is equally complicated. Yet, minimizing distraction by details is the goal. Translating natural and effective renderings of unembellished important structures to computer presentation is conceptually and practically a very difficult problem. Two basic ideas underlie the approach here: First, depicting several views and then drawing the links to identify the same object in the several views gives a sense of the position of the object vis a vis others even in many dimensions. Second, taking natural groupings of objects and examining their interrelationships allows focusing on the finer structure of the group. From these two basic principles, a conceptually coherent approach to viewing multidimensional data can be derived. Then actual methodology based on focusing and linking can be developed; user interface architectures to make efficient use of these techniques can be tried and prototypes can be implemented.
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0.915 |
1994 — 1998 |
Mcdonald, John Stuetzle, Werner [⬀] Derose, Anthony Duchamp, Thomas |
N/AActivity Code Description: No activity code was retrieved: click on the grant title for more information |
Mathematical Sciences: 3d Scanning: From Physical Objects to Electronic Models @ University of Washington
Stuetzle 9402734 The goal of this project is to develop methods that will enable rapid, automatic, and inexpensive "3D scanning"; that is, the use of optical scanning technology to create electronic models from physical objects such as a clay model of a car, or a turbine blade. 3D scanning is at present an important technology, used in a number of critical US industries, such as automobile and aerospace production. However, the expense of current scanner hardware and the need for extensive human intervention has prevented 3D scanning from achieving its full potential. The methods developed by our interdisciplinary research team will make 3D scanning far less expensive, faster, and more automatic. The goal of 3D scanning is the inverse of computer aided manufacturing: given a physical object, such as a clay model of a car, a turbine blade, a chair, or a house, create an electronic model that captures its shape and color. 3D scanning is at present an important technology in a number of critical US industries, such as aerospace and automotive production. However, the expense of current scanner hardware and the need for extensive human intervention in both data collection and modeling has prevented 3D scanning from achieving its full potential. This grant will result in new algorithms and software that will enable new scanner systems that are faster, more automatic, smaller, less expensive, model other visual properties in addition to shape, and produce higher quality and more usable output.
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0.915 |
1997 — 2000 |
Mcdonald, John W |
R01Activity Code Description: To support a discrete, specified, circumscribed project to be performed by the named investigator(s) in an area representing his or her specific interest and competencies. |
New Mammalian Hyaluronan Synthase @ Mayo Clinic Coll of Medicine, Rochester
DESCRIPTION (Adapted from the Applicant's Abstract): The long-term objectives of the research proposed are to elucidate the function and biological roles of mammalian hyaluronan synthases. Hyaluronan (HA) is a linear, unbranched glycosaminoglycan of repeating disaccharide units of [D-glucuronic acid(beta-1,3)N-acetylglucosamine(beta-1,4)]x. HA is considered a critical component of the extracellular matrix in vertebrates. HA-containing matrices define spaces in the developing embryo, providing environments favorable for cell migration such as endocardial cushions. Specific cellular receptors for HA, including CD44, RHAMM (Receptor for Hyaluronate Mediated Motility) and hepatic endothelial cell receptors mediate cell migration, growth and HA turnover. Biochemical and cell biological studies have revealed that HA, in contrast to other glycosaminoglycans, is synthesized on the inner surface of the plasma membrane of eukaryotic cells and exported as a polymer into the extracellular matrix. However, until recently, the enzymes responsible for synthesizing HA in eukaryotes have resisted molecular identification. The applicant group has utilized degenerate RT-PCR to identify cDNA clones encoding a novel protein, termed hyaluronan synthase 2 (Has2), with several putative membrane spanning sequences and highly conserved regions conserved in enzymes catalyzing beta(1-4) bond formation. Transfection of the cDNA encoding this protein results in the de novo appearance of HA synthase activity in cell membranes. They have targeted the gene in the mouse, developed antibodies, and begun to explore the expression of mHas2 in vivo. The currently proposed studies seek to establish the catalytic function and properties of purified mHas2, map its expression in the mouse in relationship to the known distribution of HA, and study the phenotype of the targeted null mutation that they have created. It is suggested by the applicant that the planned studies may elucidate the function, expression and developmental role of a new mammalian enzyme, whose putative extracellular matrix product is considered vital to normal mammalian growth and development, and implicated widely in the pathophysiology of inflammation and tissue injury.
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0.927 |
1997 — 2000 |
Mcdonald, John W |
K08Activity Code Description: To provide the opportunity for promising medical scientists with demonstrated aptitude to develop into independent investigators, or for faculty members to pursue research aspects of categorical areas applicable to the awarding unit, and aid in filling the academic faculty gap in these shortage areas within health profession's institutions of the country. |
Ampa Receptor Mediated Spinal Cord Oligodendrocyte Death
Spinal cord trauma causes extended neurologic disability, with limited treatment options, and serious social and economic consequences. Both gray and white matter damage contribute to functional disability. While recent studies have begun to identify mechanisms contributing to neuronal injury, mechanisms underlying oligodendrocyte (oligo) or axonal injury remain unclear. Understanding the mechanisms of oligo death, and the subsequent consequences relative to neuronal and axonal injury and recovery, and behavioral outcome, could provide valuable clues to novel therapies for spinal cord injury and, possibly, other neurologic diseases such as stroke. The major objective of this proposal is to systematically study excitotoxic, AMPA receptor-mediated death of oligos in vitro and determine the relative role of this mechanism in spinal cord trauma. Extracellular glutamate is known to be elevated to high levels consequent to spinal cord trauma. Our preliminary evidence suggests that oligos express high levels of AMPA-type glutamate receptors, and can be destroyed by moderate overactivation of these AMPA receptors. Expression of functional AMPA-type glutamate receptors will be examined by western blots, immunohistochemistry, dye physiology, and electrophysiology in primary culture. The hypothesis that oligos in vitro and in vivo can be destroyed by toxic overactivation of AMPA receptors will be demonstrated pharmacologically by direct application of glutamate, and AMPA receptor specific agonists and antagonists in primary culture and in vivo spinal cord preparation. The nature of AMPA receptor-mediated oligo death, necrosis vs apoptosis, will be characterized in vitro by dy physiology, EM cellular morphology, and susceptibility in Bax knock-out and Bcl-2 over-expressing murine cultures. Finally, the hypothesis that blockade of AMPA receptor- mediated oligo death will reduce white matter damage in rat model of spinal cord trauma will be tested by selective application of AMPA receptor antagonists, and studying the possible relation of oligo death and neuronal injury. The effects of these manipulations on behavioral outcome from spinal cord trauma will be assessed. If our hypothesis correct, measures directed at reducing AMPA receptor-mediated oligo death may be useful in the acute treatment of spinal cord injury.
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1 |
1998 — 2002 |
Mcdonald, John W |
R29Activity Code Description: Undocumented code - click on the grant title for more information. |
Mechanism of Oligodendrocyte Death in Spinal Cord Injury
Oligodendrocyte death and demyelination accompany many CNS insults, and these features are particularly prominent in spinal cord trauma. White matter injury, including demyelination, are the major cause of disability after spinal cord injury (SCI). Despite the clinical importance of this problem, the cellular and molecular mechanisms contributing to oligodendrocyte death are unclear. Since oligodendrocytes express functional AMPA-type glutamate receptors and elevated glutamate levels accompany SCI, we plan to explore the possibility that spinal cord oligodendrocytes are vulnerable to AMPA/kainate (KA) receptor-mediated excitotoxic death and examine whether this mechanism may contribute to the loss of oligodendrocytes and demyelination following SCI. Our preliminary data suggest oligodendrocytes, in vitro and in vivo, express functional AMPA/KA receptors, and are killed by AMPA/KA receptor overactivation. An initial characterization of the development, physiology and pathophysiology of AMPA/KA receptors will be completed in pure cultures of oligodendrocytes isolated from adult rodent spinal cord. Our preliminary data in vivo raise the specific possibility that a delayed and protracted excitotoxicity may contribute, in part, to the delayed oligodendrocyte death following SCI. If verified by these studies, this would be a novel and important concept in our understanding of the mechanisms of oligodendrocyte death, extending the excitotoxicity hypothesis to include non-neuronal cells and involvement in delayed mechanisms of SCI. The ultrastructural features and temporal pattern of oligodendrocyte death following SCI will be assessed using contusion and dorsal hemisection injury in adult rodents. Parallel studies using long term culture of intact brain and spinal cord will be carried out to investigate the mechanisms of oligodendrocyte death in the absence of factors complicating in vivo studies. We will further examine whether oligodendrocyte death and demyelination are reduced and the functional outcome improved by strategies designed to ameliorate AMPA/KA receptor excitotoxicity. The ultimate goal of this project is to enhance functional recovery after SCI, by understanding and limiting oligodendrocyte death and demyelination.
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1 |
1999 — 2001 |
Mcdonald, John F [⬀] |
F32Activity Code Description: To provide postdoctoral research training to individuals to broaden their scientific background and extend their potential for research in specified health-related areas. |
G Protein Linked Regulation of Integrins by Iap (Cd47)
Integrins initiate signaling pathways that impact tissue organization, inflammation, blood clotting, oncogenesis and angiogenesis upon binding of extracellular matrix proteins, in the regulation of biological processes. In this proposal, the role of integrin-associated protein (IAP, CD47), a co-receptor in mediating integrin signaling, will be studied by manipulation of both the receptor apparatus and the ligand structure. The C- terminal cell-binding domain (CBD) of thrombospondin (TS) is a ligand of IAP, and peptides derived from the CBD stimulate integrin-dependent processes via heterotrimeric G proteins. To define the mechanism of G protein coupling to the integrin-IAP complex, 1) a model expression system will be established for integrins, IAP and G protein subunits to evaluate receptor function in cellular assays upon treatment with IAP agonists; 2) direct measurements of G protein coupling will be carried out in the transfected cells and correlated with functional assays to identify the role of each component in the signaling complex; and 3) expression and mutagenesis of TS and CBD will be carried out to identify the determinants for IAP activation. By correlating changes in the interactions of the receptor and G protein components with downstream or "read-out" cellular functions, these studies should begin to define the molecular basis for the role of IAP in integrin-regulated biological processes such as angiogenesis, tumorigenesis and wound healing.
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0.915 |
2000 — 2002 |
Mcdonald, John W |
P01Activity Code Description: For the support of a broadly based, multidisciplinary, often long-term research program which has a specific major objective or a basic theme. A program project generally involves the organized efforts of relatively large groups, members of which are conducting research projects designed to elucidate the various aspects or components of this objective. Each research project is usually under the leadership of an established investigator. The grant can provide support for certain basic resources used by these groups in the program, including clinical components, the sharing of which facilitates the total research effort. A program project is directed toward a range of problems having a central research focus, in contrast to the usually narrower thrust of the traditional research project. Each project supported through this mechanism should contribute or be directly related to the common theme of the total research effort. These scientifically meritorious projects should demonstrate an essential element of unity and interdependence, i.e., a system of research activities and projects directed toward a well-defined research program goal. |
Hyaluronan and Atrioventricular Canal Morphogenesis
The acellular cardiac jelly matrix that separates the myocardium and endocardium in the primitive heart forms endocardial cushion swellings in two regions of the heart, the atrioventricular (AV) canal and the outflow tract. As development proceeds, a population of the endothelial cells lining the cushions undergoes an epithelial to mesenchymal transformation under the influence of myocardial-derived stimuli. Resultant migratory mesenchymal cells invade the cushion matrix to become cardiac valve precursors. Molecular genetic studies in the mouse demonstrate that both myaluronan (HA) and versican are required for formation on the cardiac cushions. Animals lacking these matrix molecules versican are required for formation of the cardiac cushions. Animals lacking these matrix molecules the compelling evidence for the role of the extracellular matrix in endocardial cushion formation, it is unclear if matrix molecules actively participate in the formation of valve structures or in the matrix provides only a supportive environment for cellular migration and differentiation. We hypothesize that HA plays two roles in AV canal morphogenesis: a) By binding to other matrix components (versican, and type VI collagen) and thus forming a structural component of the cardiac jelly and b) By signaling via a cell surface receptor-mediated mechanism upstream of Ras. Experiments are designed to examine the function and regulation of HA in each of these proposed capacities. The specific aims are: 1. Characterize the developmental expression patterns for the principal source of HA during heart development, hyaluronan synthase-2 (Has2). In addition, define the expression of molecular markers of cushion morphogenesis in mouse and chick endocardial cushions using an in vitro collagen gel transformation assay to establish the applicability of this assay for the mammalian AV canal. 2. Determine the functional role of HA during in vitro endocardial cushion morphogenesis. 3. Characterize the cis regulatory elements of the Has2 gene that are responsible for expression in the cardiac cushions. Taken together, these studies will provide a greater understanding of the biologic role of the extracellular matrix in the developing heart and provide unique reagents and techniques for future analysis of AV canal morphogenesis.
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0.964 |
2000 — 2004 |
Mcdonald, John W |
P01Activity Code Description: For the support of a broadly based, multidisciplinary, often long-term research program which has a specific major objective or a basic theme. A program project generally involves the organized efforts of relatively large groups, members of which are conducting research projects designed to elucidate the various aspects or components of this objective. Each research project is usually under the leadership of an established investigator. The grant can provide support for certain basic resources used by these groups in the program, including clinical components, the sharing of which facilitates the total research effort. A program project is directed toward a range of problems having a central research focus, in contrast to the usually narrower thrust of the traditional research project. Each project supported through this mechanism should contribute or be directly related to the common theme of the total research effort. These scientifically meritorious projects should demonstrate an essential element of unity and interdependence, i.e., a system of research activities and projects directed toward a well-defined research program goal. |
Neurotrophin Control of Thalamocortical Development
Normal development of ordered representations of the craniofacial periphery (whisker pattern in rodents) in the primary somatosensory (SmI) cortex requires peripheral input. Although it is clear that competition between cortical pattern formation. Thus, competitive interactions may not be based upon electrical events, but rather, access to a growth-promoting substance(s) that (are) produce in the central nervous system. Here, we propose to evaluate the actions of neurotrophins, normally present in these areas, upon the development of thalamocortical afferents (TCAs). Based upon observations in the developing visual system (Cabelli et al., 1995) and trigeminal primary afferents (Project 1), we hypothesize that TCAs compete for access to a limited supply of particular neurotrophins during critical periods of development, and that the spatial and temporal distribution of neurotrophins during critical periods of development, and that the spatial and temporal distribution of neurotrophins is an important determinant of thalamocortical structure and function. Specifically, NT-3 will produce axon arborization and BDNF will produce axon elongation. Augmented delivery of NT-3 and BDNF will be accomplished using three corroborative approaches that include impregnated Elvax implants (Experiment 1a), transgenic over- expression (Experiment 1b), and transplantation of neural induced ES cells containing transgenes designed to conditionally over-express each neurotrophin (Experiment 2). In Experiments 1 & 2, the dependent variable assess TCA morphologic indices including single fiber and total production analysis using neurobiotin and DiI post-mortem anterograde labeling. Experiment 2 will assess integration and differentiation of neural ES cells containing transgenes to over-express the neurotrophins. Experiment 3 will compare cortical barrel patterns to individual TCA morphologic and topographic changes observed in Experiments 1 & 2. Core A will perform labeling of TCAs and layer IV neurons and stereologic ultrastructural analysis of TCA synapses upon ES cells. Core B will produce the tetracycline regulated NT-3/BDNF transgenic mice. Core C will quantify TCA morphology and cortical C confocal microscope and quantified using stereologic methods in Core C. These studies will provide insights with transplanted ES cells will be relevant to therapeutic strategies using transplantation to restore function lost whether individual non-regionally committed neural precursors are capable of being integrated into the normal somatotopic organization of the SmI cortex and if a critical-sensitive period exists.
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1 |
2000 — 2003 |
Mcdonald, John W |
R01Activity Code Description: To support a discrete, specified, circumscribed project to be performed by the named investigator(s) in an area representing his or her specific interest and competencies. |
Es Cell Myelination in Injured Spinal Cord
DESCRIPTION: (Adapted from the Investigator's Abstract): Demyelination of intact axons is an important factor contributing to lost function in most CNS disorders. These include spinal cord injury (SCI) and multiple sclerosis, where the capacity for native cell-mediated remyelination is limited. Embryonic stem (ES) cells provide a powerful tool to investigate mechanisms of myelination. ES cells provide an advantage over other cells because they can divide indefinitely, affording an unlimited source of stem cells for culture or transplantation. Furthermore, they are genetically normal, pluripotent, and the only stem cell amenable to double allele genetic manipulation. We propose to harness the potential of the ES cell system to evaluate mechanisms of myelination. We plan to explore the possibility that ES cells, induced by retinoic acid down a neuroglial differentiation pathway, can generate oligodendrocytes (oligos) capable of axonal myelination in vitro and in vivo. Additionally, we propose to determine if ES cells can differentiate into oligos and myelinate after transplantation into the demyelinated spinal cord. We hypothesize that enhancing ES cell-derived oligo (ESoligo) differentiation and myelination will optimize behavioral recovery after SCI. We plan to build upon our previous work that demonstrated ES cell differentiation into neural cells and a modest improvement in hindlimb locomotor function even when transplantation was delayed 9 days after moderate spinal cord contusion injury. In Aim 1, we propose to optimize ESoligo differentiation and to develop enriched sources of ESoligos for culture and transplantation in subsequent experiments. One major component of Aim I is development of a PLP-lacZ transgene ES cell line that will enable ESoligo derived myelin to be identified and quantified rapidly both in vitro and in vivo. In Aim 2 we will test several strategies (screened in Aim 1) for optimizing ESoligo survival and myelination, in 2 rodent models of spinal cord demyelination. In Aim 3, we will apply the results of both previous Aims to transplantation in the most clinically relevant (but complex) model of SCI, weight-drop contusion injury. We predict that improved myelination will enhance recovery of locomotion. Once recovery is optimized, the requirement of ESoligo myelination for maintenance of locomotor recovery will be tested. This will be done by selectively inducing myelin-producing ESoligos to undergo apoptotic death using a knocked-in bar-overexpression gene, driven by a myelin-specific PLP promotor. The long-term goal of this project is to develop the ES cell system as a research and therapeutic tool aimed at understanding the mechanisms of remyelination
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1 |
2000 — 2002 |
Mcdonald, John W |
P01Activity Code Description: For the support of a broadly based, multidisciplinary, often long-term research program which has a specific major objective or a basic theme. A program project generally involves the organized efforts of relatively large groups, members of which are conducting research projects designed to elucidate the various aspects or components of this objective. Each research project is usually under the leadership of an established investigator. The grant can provide support for certain basic resources used by these groups in the program, including clinical components, the sharing of which facilitates the total research effort. A program project is directed toward a range of problems having a central research focus, in contrast to the usually narrower thrust of the traditional research project. Each project supported through this mechanism should contribute or be directly related to the common theme of the total research effort. These scientifically meritorious projects should demonstrate an essential element of unity and interdependence, i.e., a system of research activities and projects directed toward a well-defined research program goal. |
Survival &Differentiation of Esnlcs After Transplant
DESCRIPTION (adapted from the abstract): Project 3 proposes to explore whether murine ES cells, induced down a neuroglial lineage by ex vivo pharmacological and/or genetic manipulation, can survive transplantation into the syrinx or a contused adult rat spinal cord; differentiate into neurons, oligodendrocytes. contused adult rat spinal cord; differentiate into neurons, oligodendrocytes, and astrocytes functional recovery. The particular focus of this grant is to understand the mechanisms of ES cell death following transplantation into the syrinx (9 days following contusion) and to reduce death by protective mechanisms, both pharmacologically and genetically based. Preliminary studies, while suggesting glial (predominantly) and neuronal (minor amounts) differentiation by the cells following engraftment into a contusion- induced syrinx, also demonstrated that substantial donor ES cell death occurred after transplantation. The investigators hypothesize that this cell death is likely limiting functional benefit from the engraftment procedure. Therefore, they propose how to investigate minimizing that death in situ, particularly death mediated by apoptotic (predominantly in the first post traumatic 48 hours) and excitotoxic (predominantly after the first 2 post-injury days) mechanisms, by specific pharmacological and genetic interventions speculating that such an outcome will optimize functional recovery. Genetic manipulations (e.g., over-expression of bcl-2 or deletion of Bax or caspase 9 genes) will be created in the ES Cell Genetic Engineering Core B; pharmacological approaches will be derived from the studies performed in Projects I & II (e.g., the pan-caspase inhibitor ZVAD or the glutamate receptor antagonist MK-801). The survival and differentiation fate of donor ES cells (identified by a number of marking techniques, including a lacZ transgene intrinsic to the cell or to cell type- specific structures, BrdU pre-incubation of donor cells, non-diffusible fluorescent cytoplasmic dyes, mouse-specific chromosomal sequences or cell surface markers that will not cross-react with rat host cells) will be assessed quantitatively at defined intervals after transplantation. The anatomical, physiological, and functional impact of ES transplantation will be determined in conjunction with Project IV ("Integration of transplanted ESNLCs in spinal circuits) and the "Injury and functional assessment core".
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1 |
2001 — 2003 |
Mcdonald, John W |
R01Activity Code Description: To support a discrete, specified, circumscribed project to be performed by the named investigator(s) in an area representing his or her specific interest and competencies. |
Role of Integrins in Cardiac Myocytes
DESCRIPTION (provided by applicant): Integrins, heterodimeric transmembrane receptors linking extracellular matrix molecules with cytoskeletal proteins and signaling complexes, are essential in normal cardiac development, cardiomyocyte differentiation, and maintenance of sarcomere organization. Induced mutations in mice demonstrate the importance of integrins and their ligands in maintenance of cardiac muscle function. Integrins not only mediate cell adhesion, but also serve as stretch receptors and co-receptors in growth factor stimulated pathways. We hypothesize that integrins function as important modulators in the heart, sensing and responding to mechanical and endocrine stimuli to maintain homeostasis. We have used in vitro models and in vivo expression to begin to this hypotheses. In vitro studies demonstrate that integrin ligation to extracellular matrix and integrin signaling is required for cardiomyocytes to respond to hypertrophic agonists acting via G-protein coupled receptors. Complementary in vivo studies demonstrate that transgenic expression of a gain of function mutation in the integrin a5 subunit, or expressing a chimeric protein interfering with integrin function results in a severe, perinatal lethal phenotype in transgenic mice The proposed studies will utilize an integrated approach to further dissect the role of integrins in the structure and function of cardiac myocytes. The role of proximal mediators of integrin signaling in the hypertrophic response of cardiac myocytes will be evaluated with an in vitro model system of cultured myocytes. The importance of candidate integrin effectors identified in the in vitro system will be validated or refuted by overexpressing these candidate genes in transgenic animals. A refined conditional transgene expression system will determine the effect of transgene expression in the adult heart. Cardiac phenotypes resulting from transgene expression will be correlated with morphological and molecular alterations observed in myocytes in vitro. Finally, the physiological correlates of transgene expression will be examined by determining the effect of transgene expression on cardiac function under basal conditions and after hemodynamic loading. These studies will provide new insights into myocyte signaling pathways and approaches applicable to pathologic alterations in the human myocardium.
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0.976 |
2002 |
Mcdonald, John W |
T32Activity Code Description: To enable institutions to make National Research Service Awards to individuals selected by them for predoctoral and postdoctoral research training in specified shortage areas. |
Cellular and Molecular Responses in Lung Disease
The primary goal of this proposed program is to train young physician- scientists for a full-time academic career in pulmonary research. The emphasis will be placed on developing and cultivating highly qualified trainees, allowing them to acquire the necessary knowledge and skills required to evolve as independent investigators. The research will be conducted under the personal preceptorship of active senior investigators in the departments of Medicine, Pediatrics, Biology, Biochemistry, Pathology or Human Genetics at the University of Utah. The training program utilizes established strengths at the University of genetics and molecular biology while the patient-oriented research is aligned with ongoing investigations in acute lung injury, in particular the Acute Respiratory Distress Syndrome (ARDS). Our research training philosophy is that such training can best be achieved on the basis of the most direct day-to-day interaction between trainees and faculty preceptors who have demonstrated success in preparing individuals for careers in research. A highly conducive environment for a multi- disciplinary approach exists due to the close collaborative ties already developed among various preceptors and evolving associations and collaborations. The preceptorial research training will be supplemented with formal course work, lectures, conferences, seminars, and other pertinent educational modalities in order to prepare the trainees to formulate innovative and meritorious research programs in pulmonary diseases at the conclusion of their training. The proposed preceptors represent a group of active scientists engaged in research in five interrelated thematic areas relevant to lung health and disease. Each preceptor has an NIH-funded productive research program. The thematic areas include: 1) Leukocyte Biology; 2) Vascular Cell Biology; 3) Developmental Biology and Aging; 4) Human Genetic Diseases; and 5) Patient-Oriented Research. We believe the program will enable the trainees to master the complexities of modern biomedical research, and will provide an appreciation for the collaborative interdisciplinary approach required for research into medical problems.
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0.976 |