Browsing by Subject "BMP"

Now showing 1 - 5 of 5
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    Development and Cancer: The role of Twisted Gastrulation in mammary gland development and in cancer.
    (2014-11) Forsman, Cynthia
    It is becoming increasingly clear that the molecular mechanisms that maintain and promote pluripotency during development reemerge as important mediators of tumorigenicity. Bone morphogenetic proteins (BMPs) and their modulators play numerous and diverse roles during development and, as recent evidence suggests, in cancer. One key modulator of BMP signaling during craniofacial and mammary gland development is the glycoprotein Twisted gastrulation-1 (TWSG1). The loss of Twsg1 results in craniofacial malformations, a delay in mammary gland development and lactation defects. TWSG1 has been shown to function both in the positive and negative regulation of BMP signaling. This dual nature may be explained first by TWSG1's ability to bind BMPs and prevent their interaction with receptors. This function is similar to other extracellular BMP antagonists such as Noggin and Gremlin. Additionally, the TWSG1: BMP ligand complex can be joined by Chordin and when this tripartite complex is formed Tolloid can cleave Chordin releasing BMPs into the extracellular space at some concentration. The timing of this release and availability of other extracellular partners may, in part, dictate the influence TWSG1 has on BMP signaling. Interestingly, TWSG1 overexpression has been detected in tumors of tissues in which it also plays a key role in development such as the oral cavity and breast. It therefore provides an interesting model by which to investigate the tenuous balance between pluripotency and tumorigenesis.
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    Farmer beliefs and personal norms associated with nitrogen best management practices in the Rush River and Elm Creek Watersheds, Mn
    (2013-05) Olson, Bjorn Anders
    Nitrogen from agricultural nonpoint source pollution is a primary cause of water quality impairments in the Mississippi River Basin. The cumulative effects of nitrogen loading cause water resource problems at local, regional, and national scales as epitomized by the hypoxic "dead zone" at the mouth of the Mississippi River. Agricultural best management practices (BMPs) designed to reduce nitrogen runoff are promoted across the U.S., yet adoption rates are discouragingly low. This study explores farmer perspectives on BMP adoption using interviews with 30 farmers across two agricultural watersheds in southern Minnesota. The research questions that drove this study are 1) What drives nitrogen best management practice adoption among farmers in the study watersheds? 2) What constrains nitrogen best management practice adoption?, and, 3) What role do personal norms play in influencing best management practice decisions? Study findings suggest that three primary drivers (land stewardship, economics, and personal responsibility) motivate BMP adoption; seven primary constraints (including economics, knowledge, and autonomy) hinder adoption; and egoistic, social/altruistic, and biospheric-driven personal norms play varied and influential roles in BMP adoption. An understanding of how drivers, constraints, and personal norms combine to influence farmer decision-making processes is described using the Norm Activation Theory. These drivers, constraints, and the role of personal norms may prove useful when approaching farmers to participate in conservation programs or in tailoring conservation programs to fit farmers' needs.
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    In situ sensors for monitoring BMP performance and in-stream pollutant loading
    (2012-12) Dienhart, Alissa Catherine
    For this research, a sensor network was used to evaluate pollutant loads and concentrations in the targeted portions of streams and to evaluate the performance of pond/wetland stormwater best management practices (BMPs). The study sites were chosen to examine whether BMPs achieve their intended purpose of improving surface water quality. This data was also collected with intent of examining whether a sensor network could provide more a more efficient and comprehensive means of monitoring surface waters and BMP systems. Violations of water quality standards for turbidity, dissolved oxygen, and chloride (chronic) were periodically observed at both sampling locations. Measured concentrations of pollutants we converted to loading rates to determine flow profile influences on water quality. Dissolved oxygen and chloride violations were generally observed during periods of low flow, while those for turbidity were generally independent of flow. Water quality downstream of BMPs was often (but not always) better than upstream water quality, suggesting that BMPs controlling stormwater inflow are not contributing to the degradation of downstream water quality. Analysis of water quality before and during rain events indicates that chloride and suspended solids are controlled in the pond/wetland systems studied. Evidence for phosphorus removal was also obtained.
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    The Regulation And Function Of Bmps In Osteoclastogenesis
    (2019-06) Huntley, Raphael
    Bone morphogenetic proteins (BMPs) play a large role in the formation and maintenance of the skeleton, and, in recent years, have become a common clinical adjuvant. The regulatory processes tightly control BMP gradients, which can stimulate both osteoblasts to build bone, and osteoclasts to resorb bone. This thesis discusses data from multiple in-vitro and in-vivo BMP-related knockout models to elucidate the different function BMPs have on osteoclast differentiation and activity. We elucidate the mechanism by which BMP signaling is tightly controlled by Twisted Gastrulation, an extracellular BMP binding protein. Using an murine model we also show osteoclast derived BMP2 acts to regulate bone mineral density in-vivo, and can function to coordinate osteoblast matrix deposition.
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    The regulation of osteoclastogenesis by bone morphogenetic proteins, twisted gastrulation, and histone deacetylases.
    (2012-08) Pham, Lan Dang
    Bone morphogenetic proteins (BMPs) are well-studied regulators of osteoblasts, and are used in a number of craniofacial and orthopedic procedures to promote localized bone formation. Studies of skeletal tissue has shed light on BMPʼs role as an inducer of chondrocytic and osteoblastic differentiation and function. BMPs have been used successfully in studies to: treat critical sized defects in both long and craniofacial bones; enhance fracture healing; treat nonunions and lumbar spinal fusion; and regenerate alveolar bone and portions of teeth such as dentin and pulp. However, it has been difficult to determine the optimal concentrations, appropriate temporal release, and regulation of BMPs, as both a deficiency and an excess of BMPs may lead to pathologic states. Furthermore, the cellular and molecular origin of this BMP-associated stimulation of bone resorption remains poorly understood. The data presented in this thesis will help us better understand the modulation of osteoclastogenesis and bone resorption by the regulatory proteins BMP-2, Twisted gastrulation, and Histone deacetylase 3 and 7. The knowledge gained by studying these regulators in osteoclasts should provide important new insight into the use of BMPs in bone generation procedures, its role in pathogenesis of bone resorptive disorders, and provide a conceptual framework for the development of successful therapies and bone regenerative strategies for diseases associated with increased bone loss and defective bone formation.