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Background Osteosarcoma (OS) is the most common primary bone tumor, with a propensity to metastasize to the lungs. Five-year survival for metastatic OS is below 30%, and has not improved for several decades despite the introduction of multi-agent chemotherapy. Understanding OS cell migration to the lungs requires an evaluation of the lung microenvironment. Here we utilized an in vitro lung cell and OS cell co-culture model to explore the interactions between OS and lung cells, hypothesizing that lung cells would promote OS cell migration and survival. The impact of a novel anti-OS chemotherapy on OS migration and survival in the lung microenvironment was also examined. Methods Three human OS cell lines (SJSA-1, Saos-2, U-2) and two human lung cell lines (HULEC-5a, MRC-5) were cultured according to American Type Culture Collection recommendations. Human lung cell lines were cultured in growth medium for 72 h to create conditioned media. OS proliferation was evaluated in lung co-culture and conditioned media microenvironment, with a murine fibroblast cell line (NIH-3 T3) in fresh growth medium as controls. Migration and invasion were measured using a real-time cell analysis system. Real-time PCR was utilized to probe for Aldehyde Dehydrogenase (ALDH1) expression. Osteosarcoma cells were also transduced with a lentivirus encoding for GFP to permit morphologic analysis with fluorescence microscopy. The anti-OS efficacy of Disulfiram, an ALDH-inhibitor previously shown to inhibit OS cell proliferation and metastasis in vitro, was evaluated in each microenvironment. Results Lung-cell conditioned medium promoted osteosarcoma cell migration, with a significantly higher attractive effect on all three osteosarcoma cell lines compared to basic growth medium, 10% serum containing medium, and NIH-3 T3 conditioned medium (p <0.05). Lung cell conditioned medium induced cell morphologic changes, as demonstrated with GFP-labeled cells. OS cells cultured in lung cell conditioned medi

Background Osteosarcoma (OS) is the most common primary bone tumor, with a propensity to metastasize to the lungs. Five-year survival for metastatic OS is below 30%, and has not improved for several decades despite the introduction of multi-agent chemotherapy. Understanding OS cell migration to the lungs requires an evaluation of the lung microenvironment. Here we utilized an in vitro lung cell and OS cell co-culture model to explore the interactions between OS and lung cells, hypothesizing that lung cells would promote OS cell migration and survival. The impact of a novel anti-OS chemotherapy on OS migration and survival in the lung microenvironment was also examined. Methods Three human OS cell lines (SJSA-1, Saos-2, U-2) and two human lung cell lines (HULEC-5a, MRC-5) were cultured according to American Type Culture Collection recommendations. Human lung cell lines were cultured in growth medium for 72 h to create conditioned media. OS proliferation was evaluated in lung co-culture and conditioned media microenvironment, with a murine fibroblast cell line (NIH-3 T3) in fresh growth medium as controls. Migration and invasion were measured using a real-time cell analysis system. Real-time PCR was utilized to probe for Aldehyde Dehydrogenase (ALDH1) expression. Osteosarcoma cells were also transduced with a lentivirus encoding for GFP to permit morphologic analysis with fluorescence microscopy. The anti-OS efficacy of Disulfiram, an ALDH-inhibitor previously shown to inhibit OS cell proliferation and metastasis in vitro, was evaluated in each microenvironment. Results Lung-cell conditioned medium promoted osteosarcoma cell migration, with a significantly higher attractive effect on all three osteosarcoma cell lines compared to basic growth medium, 10% serum containing medium, and NIH-3 T3 conditioned medium (p <0.05). Lung cell conditioned medium induced cell morphologic changes, as demonstrated with GFP-labeled cells. OS cells cultured in lung cell conditioned medi

Nucleic acids, the biomolecules of life, have demanded the attention of chemists and biologists for greater than a century. The ability to investigate, in detail, the structure, function and the interplay between the two has driven the development of novel approaches for the investigation of these concepts. Fluorescence spectroscopy, a technique that protein chemists have utilized for many years due to the inherent favorable photophysical properties of select naturally occurring amino acids, has gained tremendous interest by nucleic acids scientists in recent decades. The lack of naturally occurring nucleosides with favorable photophysical properties has driven the design and application of novel fluorescent nucleosides. Towards this pursuit, we have described guidelines that will enable us to systematically identify novel heterocycles with both favorable photophysical and structural properties. Utilizing our design principles, we have explored the idea of conjugating small five membered ring heterocycles, namely furan, thiophene, oxazole and thiazole, to both the pyrimidine and purine nuclei. This has resulted in seven emissive nucleosides, of which two have emerged with desirable photophysical properties after incorporation into oligonucleotides. The furanyl thymidine analogue has been shown to positively and non- destructively detect the presence of abasic sites. This is an important advancement since most methods used to detect abasic sites result in the destruction of the target strand. The furanyl thymidine analogue has also redefined the polarity of the grooves in various DNA polymorphs. In addition, it has been shown that DNA polymerase accepts the triphosphate form of the furanyl thymidine analogue, thereby making it attractive to a wider biochemical audience. In the push to investigate more than just thymidine analogues, a furanyl cytidine analogue has been site specifically incorporated into an oligonucleotide, where its photophysical properties are curre

Nucleic acids, the biomolecules of life, have demanded the attention of chemists and biologists for greater than a century. The ability to investigate, in detail, the structure, function and the interplay between the two has driven the development of novel approaches for the investigation of these concepts. Fluorescence spectroscopy, a technique that protein chemists have utilized for many years due to the inherent favorable photophysical properties of select naturally occurring amino acids, has gained tremendous interest by nucleic acids scientists in recent decades. The lack of naturally occurring nucleosides with favorable photophysical properties has driven the design and application of novel fluorescent nucleosides. Towards this pursuit, we have described guidelines that will enable us to systematically identify novel heterocycles with both favorable photophysical and structural properties. Utilizing our design principles, we have explored the idea of conjugating small five membered ring heterocycles, namely furan, thiophene, oxazole and thiazole, to both the pyrimidine and purine nuclei. This has resulted in seven emissive nucleosides, of which two have emerged with desirable photophysical properties after incorporation into oligonucleotides. The furanyl thymidine analogue has been shown to positively and non- destructively detect the presence of abasic sites. This is an important advancement since most methods used to detect abasic sites result in the destruction of the target strand. The furanyl thymidine analogue has also redefined the polarity of the grooves in various DNA polymorphs. In addition, it has been shown that DNA polymerase accepts the triphosphate form of the furanyl thymidine analogue, thereby making it attractive to a wider biochemical audience. In the push to investigate more than just thymidine analogues, a furanyl cytidine analogue has been site specifically incorporated into an oligonucleotide, where its photophysical properties are curre

Osteosarcoma (OS), chondrosarcoma (CSA), and Ewings sarcoma (ES) are the most common primary malignancies of bone, and are rare diseases. As with all sarcomas, the prognosis of these diseases ultimately depends on the presence of metastatic disease. Survival is therefore closely linked with the biology and metastatic potential of a particular bone tumor's cells. Here we describe a significant correlation of aldehyde dehydrogenase (ALDH) activity and the presence/absence of distant metastases in ten consecutive cases of human bone sarcomas. Additionally, cultured human CSA cells, which are historically chemo- and radio-resistant, may be sensitive to the ALDH inhibitor, disulfiram. While it is premature to draw broad conclusions from such a small series, the importance of ALDH activity and inhibition in the metastatic potential of primary bone sarcomas should be investigated further.

Osteosarcoma (OS), chondrosarcoma (CSA), and Ewings sarcoma (ES) are the most common primary malignancies of bone, and are rare diseases. As with all sarcomas, the prognosis of these diseases ultimately depends on the presence of metastatic disease. Survival is therefore closely linked with the biology and metastatic potential of a particular bone tumor's cells. Here we describe a significant correlation of aldehyde dehydrogenase (ALDH) activity and the presence/absence of distant metastases in ten consecutive cases of human bone sarcomas. Additionally, cultured human CSA cells, which are historically chemo- and radio-resistant, may be sensitive to the ALDH inhibitor, disulfiram. While it is premature to draw broad conclusions from such a small series, the importance of ALDH activity and inhibition in the metastatic potential of primary bone sarcomas should be investigated further.

The majority of writings on David Bowie have focussed on his early work. Many feel that Bowie's early work has much merit, as has been made clear by the vast pool of both academic and popular writings regarding his work in the early 1970s, his collaborations with Brian Eno in the late 1970s, and his most commercially accepted works in the early 1980s. However, much of the academic writing on Bowie has chosen to focus only on these works and ignores his more recent material. This thesis contributes to the body of knowledge regarding the more recent work of David Bowie. In 1995, Bowie released the album 1. Outside. Through its music and lyrics, album art, accompanying narrative, music video and live performance, Bowie presents a world of the absurd and violent. He engages with the notions of murder as art, body modification as ritual, and the state of society at the end of the twentieth century. Bowie, in his comments to Ian Penman in Esquire magazine, suggests that the proliferation of body modification in late twentieth century Western society acts as a replacement for the Judeao-Christian ethic. By applying Victor Tumer's theory ofliminality, it is argued that, through 1. Outside, Bowie is constructing a representation of a space which is analogous to society at the end of the millennium. For Turner, the liminal stage embodies an optimistic "storehouse of possibilities," not unlike a gestation period which precedes new life. Rather than creating a space which fits Turner's model of the liminal exactly, Bowie suggests a space which is liminoid, not exhibiting the full potential of the liminal. Bowie presents themes of nihilism and the alienation of technology, as well as many juxtapositions in visual performance, which serve to give the album a sense of ambiguity contributing to its ambivalent, and thus liminoid, character., Master of Arts (MA)