This project aims to investigate and analyze crucial aspects related to the deployment of Small Modular Reactors (SMRs) in Sweden. SMRs have risen as a competitor to large-scale nuclear power plants with cost-competitiveness and cogeneration purposes in focus. Alongside the advantages of SMRs, it is important to address the non-proliferation and safeguards aspects of the deployment of SMRs in Sweden. The first stage of this project aimed to predict the electricity consumption in Sweden in 2045. Based on scenarios made by researchers and authorities, a prediction was made that the electricity consumption in Sweden will be approximately 240 TWh in 2045. Subsequently, a study was conducted to assess the suitability of different SMR concepts for deployment in Sweden. The results were that the GE Hitachi BWRX-300 and the Rolls Royce SMR are the concepts most suitable for electricity generation and the VTT LDR 50-SMR is suitable for district heating in Sweden. Based on the predicted electricity consumption and the predicted need for district heating, the SMRs were deployed in three different scenarios which yield the following results: In scenario i), a total of 15-23 SMRs were deployed to the existing nuclear sites in Sweden. (15 SMRs if BWRX-300 is chosen and 23 SMRs if the Rolls Royce SMR is chosen). In scenario ii), 16-24 SMRs in total were deployed to bidding area 1 (SE1), SE2, and SE4. In scenario iii), a total of 25 new reactors were deployed to eight different sites, close to where the electricity consumption was predicted to be large. The implications on material accounting and safeguards from the deployment in the scenarios were that the transportation and storage of spent nuclear fuel will rise by roughly a factor of two, depending on which scenario is chosen and the choice of SMR. There will be more sites for inspectors to visit. New harbors need to be built and licensed. New transportation infrastructure may need to be developed if scenario three is implemented. Furthermore, a new intermediate storage of spent nuclear fuel may be needed.

No description available.

Thymidine kinase 1 (TK1) is a cancer biomarker which has diagnostic and prognostic potential in a variety of malignancies. TK1 is significantly elevated in the serum and tumor tissue of most malignancies. This increase in TK1 can be detected in the very early stages of malignancy, including in pre-malignant disease with an increased risk for progression. Several studies have demonstrated that elevated TK1 is found in serum months before any clinical symptoms of malignancy. It has also been demonstrated that TK1 is elevated months before clinical recurrence of malignancy. This work first sought to demonstrate the early nature of TK1 expression in breast tumor tissue and pre-malignant tissue. We found that TK1 is elevated in breast hyperplasia tissue and breast carcinoma tissue. In this study we also identified some cases of ‘normal’ tumor margins (considered normal by current pathological standards) which also had elevated TK1 expression. Conversely, true normal breast tissue from noncancerous individuals had no reported elevation in TK1 expression. This study illustrated that TK1 is elevated in pre-malignant breast hyperplasia tissue, as well as some 'normal' tumor margins. TK1 expression was significantly elevated in lung, prostate, colon, esophagus, stomach, liver, and kidney tissues. This work further investigated TK1 expression in a variety of malignant tissue including the two leading causes of cancer mortality in men: lung and prostate cancer. In our study, TK1 was significantly elevated in lung and prostate cancer but not significantly elevated in prostate hyperplasia tissue. TK1 expression also increased with increasing grade in prostate carcinoma tissue. Overall, this work demonstrated that TK1 is a good universal marker of malignancy and is elevated in early cancer development. Despite the potential for TK1 as both a screening and monitoring treatment tool, there have been significant challenges associated with developing a clinically relevant method of TK1 detection. This work proposes one clinically relevant method of detection, namely a TK1 ELISA. Using preoperable lung cancer patients and normal controls, we developed a sensitive and specific ELISA which shows highly statistically significant differences in serum TK1 levels between stage 1 and stage 2 lung cancer compared with normal controls. In fact, this TK1 ELISA is more sensitive and accurate than the traditional TK radioassay, which was unable to detect differences in TK1 between early stage lung cancer and normal patients. Although elevated TK1 is not lung cancer specific, we reported significantly elevated TK1 levels in lung cancer sputum. Screening of sputum and serum for TK1 may be one method for the early detection of lung cancer. Overall, we report TK1 has promising diagnostic potential in a variety of malignancies. We also propose one sensitive and specific method to detect TK1 levels which may easily be adapted to meet current clinical applications. We hope this work will help propel TK1 forward into clinical view in the coming years.

Skeletal muscle development and function is governed by a conserved set of Transcription Factors (TFs) that regulate gene expression. The TF gene regulation is stimulus driven and cell-type and time point specific. TBX5 is an essential dosage sensitive regulator of heart and limb development. In the skeletal system, TBX5 is expressed in early stages in the lateral plate mesoderm and gives rise to the forelimb. TBX5 is also involved in proliferation and differentiation and survival pathways in both heart and limb development. Mutations in TBX5 gene lead to HOS which is characterized by various types of cardiac and musculoskeletal defects. TBX5 mechanism of action and its spatiotemporal function in skeletal muscle development has yet to be fully understood. TBX5 regulation is controlled through various factors such as alternative splicing, protein-protein interactions, Post-Translational Modifications (PTMs) and microRNAs. To date, many TBX5 interactors have been identified in cardiac cells however TBX5 protein interactors and target genes in skeletal muscle cells have not been studied. Understanding the protein interactome of TBX5 in skeletal muscle will enhance the current understanding of its mechanism of action. In this study we have characterized TBX5 with focus on its regulation, expression and biochemical properties in cardiac and skeletal muscle cells and moreover its mechanism of action specifically in skeletal muscle proliferation and differentiation. Chapter 1 discusses TBX5 regulation through alternative splicing leading to the existence of 5 distinct TBX5 isoforms with variable transcriptional activity, cardiac and limb expression pattern, biochemical properties and function. We show the pro-proliferation role of TBX5a in myoblasts while TBX5c shows to be pro-differentiation leading to the formation of myotubes in skeletal muscle C2C12 myoblasts. This opposing role of the two TBX5 isoforms lead us to studying TBX5 mechanism of action in proliferation and differentiation of skeletal muscle cells. In this study using a mass spectrometry-based approach we have identified novel TBX5 interacting partners in skeletal muscle cells for the first time by using stably overexpressed 3xFlag TBX5 via retroviral transduction in C2C12 cell line. Nuclear protein extracts were immunoprecipitated and sent for HPLC-ESI-MS/MS to identify potential protein partners of TBX5 in skeletal muscle cells. Moreover, the same stable cell line was used to identify TBX5 downstream target genes in these cell types by sending RNA extracts for microarray analysis. Amongst the 200 protein interactors identified, MYBBP1a and TBX5 interaction was confirmed and studied. The microarray analysis identified over 1200 differentially expressed genes and potential downstream targets of TBX5a from which Myostatin (Mstn) and Cyclin D2 (CcnD2) were both significantly upregulated and further confirmed and studied in relation to proliferation and differentiation in skeletal muscle cells. Chapter 2 focuses on the cooperative interaction between TBX5a and MYBBP1a inhibiting muscle specific gene promoter, Myogenin (MyoG). TBX5a and TBX5c seem to both interact with MYBBP1a but result in variable transcriptional activity of both MyoG and Mstn gene promoters. We show that TBX5 is upstream of Mstn, it binds to the promoter on specific TBE sites, and is able to upregulate Mstn promoter activation. In vivo, we show that MDX mice limb skeletal muscle tissues show elevated levels of TBX5, MYBBP1a and MSTN expression which suggest that the TBX5 pathway is associated with and indicative of the onset of proliferation and regeneration in MDX skeletal muscle tissue. Chapter 3 discusses the role of TBX5 in proliferation and regeneration of skeletal muscle cells by identifying that TBX5 binds to CcnD2 promoter and upregulates its activation which is a known cell cycle gene critical in cell proliferation and survival. Moreover, we identify GATA4 as a TBX5a cofactor in myoblast proliferation and show synergistic activation of Ccnd2 promoter by cooperative TBX5a and GATA4 action. We further show that Tbx5 heterozygote mice exhibit decreased levels of CCND2 and other proliferation markers, as well as decreased expression of PAX7 (marker of satellite cells) compared to WT skeletal muscle tissues. We also show that the heterozygous loss of Tbx5 impairs the process of regeneration in a cardiotoxin-induced injury model in mouse limb tissues. Tbx5 heterozygote mice exhibit less proliferation and impaired regeneration 4 days after injury, followed by decreased formation of regenerated fibers by 7 days post-injury compared to the wildtype mice skeletal muscle tissues; suggesting that TBX5 function is important in maintaining adult muscle regenerative capacity. Together, this study has characterized TBX5 isoforms and identified novel TBX5 protein partners and targets in the skeletal muscle cells and sheds light on TBX5 regulatory mechanism in proliferation and differentiation of skeletal muscle cells and its potential implications in HOS and other muscular diseases.

CXCL16 is an interferon-inducible chemokine of the CXC-subfamily and functions as an adhesion molecule, when membrane bound, and a chemoattractant when soluble. Upregulation of cell associated CXCL16 (cCXCL16) in colorectal cancer is associated with increased tumor infiltrating lymphocytes and good prognosis. ADAM10 and ADAM17 are metalloproteinases responsible for cleaving CXCL16, releasing soluble CXCL16 (sCXCL16) and contributing to proliferation and migration of mesangial cells, in kidney inflammatory disease. We hypothesize that cCXCL16 is a substrate for ADAM10 and ADAM17 cleavage in colorectal cancer, releasing sCXCL16, which mediates cell proliferation. To this end, we first identified CXCL16 in the human colon carcinoma cell line, RKO, by immunohistochemistry. cCXCL16 was found in the membrane, cytoplasm and nucleus. We treated RKO, in vitro, with an inflammatory cytokine mix containing 1.4 nM rhIFN[gamma], 2.0 nM rhTNF[alpha] and 2.0 nM rhIL1[beta] to increase the cleavage of cCXCL16 to sCXCL16. Overnight incubation with the cytokine mix significantly (P=.004) increased the release of sCXCL16 compared to normal conditions. To confirm that a metalloproteinase is responsible for the cleavage of cCXCL16, we used a broad spectrum metalloproteinase inhibitor, GM6001, in combination with inflammatory stimulation, in cell culture. We assayed the supernatant using ELISA for sCXCL16. GM6001 at 100 [mu]M decreased sCXCL16 to levels indistinguishable from the background. Using siRNA, we knocked down the expression of ADAM10 and ADAM17, independently, to determine if the activity of each on cCXCL16 was mediated by inflammatory stimulation. It was shown that ADAM10 constitutively cleaved cCXCL16, and ADAM17 cleavage activity was induced by inflammatory stimulation. To determine if sCXCL16 increased colorectal cancer cell (CRC) proliferation through ligand-receptor binding, we treated cells with a range of rhCXCL16 from 3.125-100 ng/mL. rhCXCL16 did not increase RKO proliferation at doses up to 100 ng/mL. We used GM6001, to inhibit the cleavage of cCXCL16 into sCXCL16 then performed an ATPase assay and 6 day cell cycle analysis, under inflammatory stimulation. Increased cleavage of cCXCL16 induced by inflammatory stimulation with the cytokine mix containing 1.4 nM rhIFN[gamma], 2.0 nM rhTNF[alpha] and 2.0 nM rhIL1[beta], increased RKO proliferation and reduced apoptosis. We conclude that ADAM10 and ADAM17 cleavage of cCXCL16 to sCXCL16 is increased by ADAM17 activation with inflammatory stimulation. The cleavage of the extracellular portion from cCXCL16 is associated with increased proliferation and decreased apoptosis of colorectal cancer cells.

<p>Bioelectricity, or endogenous electrical signaling mediated by the dynamic distribution of charged molecules, is an ancient signaling mechanism conserved across living organisms. Increasing evidence has revealed that bioelectric signals play a critical role in many diverse aspects of biology such as embryonic development, cell migration, regeneration, cancer, and other diseases. However, direct visualization and manipulation of bioelectricity during development are lacking. Neuroscience has developed tools such as GEVIs (genetically encoded voltage indicators) and chemogenetics like DREADDs (designer receptor exclusively activated by designer drugs) which allow for real–time voltage monitoring and activation of mutated receptors by inert molecules for perturbing membrane potential (Vm). To uncover bioelectric activity during development, we generated a whole-zebrafish transgenic GEVI reporter line and characterized the electrical signaling during early embryogenesis using light sheet microscopy (LSM). Additionally, we generated tissue-specific transgenic lines that combined GEVIs and chemogenetic DREADD tools to manipulate Vm. We found zebrafish embryos display stage-specific characteristic bioelectric signals during the cleavage, blastula, gastrula, and segmentation periods. Furthermore, activation of DREADDs was able to alter cell-specific GEVI fluorescence intensity and could cause a melanophore hyperpigmentation phenotype. Ultimately, these results provide the first real-time systematic analysis of endogenous bioelectricity during vertebrate embryonic development. Additionally, we generated and tested zebrafish transgenic lines for simultaneous visualization and chemogenetic manipulation of Vm during development. These results provide a better understanding of developmental bioelectricity and new tools for future studies, which could eventually help uncover the cellular electric mechanisms behind tissue patterning and disease.</p>

Comparative study of homologous structures in closely related species allows the identification of changes in gene regulatory mechanisms and their impact on the evolution of developmental processes. Nematodes, the invertebrate roundworms, are well suited for such studies, especially the Caenorhabditis briggsae and its famous cousin C. elegans. These two worms diverged from a common ancestor roughly 30 million years ago, yet appear morphologically almost identical. My Ph.D. thesis has focused on a set of nuclear factors in C. briggsae that negatively regulate cell proliferation to generate the hermaphrodite-specific mating and egg-laying organ, i.e., vulva. To this end, I have taken a two-pronged approach: one, developing resources to facilitate genetic and genomic studies in this species, and two, characterizing the roles of a novel class of genes and known repressors of vulval development. My work has uncovered substantial differences in the underlying genetic networks that regulate vulva formation in C. briggsae and C. elegans. / Thesis / Candidate in Philosophy

E-cigarettes have recently become increasingly popular, especially amongst middle and high school students. Although they are marketed as safer alternatives to tobacco cigarettes, they produce toxic metals and carcinogenic nitrosamines. This thesis studies the effects of e-cigarette aerosol on the growth and proliferation of oral epithelial cells because the consequences of vaping, including a potential risk for aberrant growth leading to cancer, are not well understood. Cells were grown in matrigel, causing the formation of three-dimensional spheroids modeling the physiological architecture of the oral epithelium. Those spheroids were chronically exposed to vape with different treatment conditions to study the functional biological effects of the presence of nicotine, dosage, and different types of exposure. The diameter of the spheroids was measured throughout the process as an indicator of cell growth. It showed that the vape exposure, especially nicotine-rich aerosol, induces an increase in spheroid diameter in a dose-dependent manner. The increased cell growth is supported by enhanced metabolic activity as well as increased aldehyde dehydrogenase activity, a marker of stemness prominently upregulated in cancer stem cells. Protein was extracted at the end for protein expression analysis through Western blotting and the identification of the activation of survival signaling pathways and stem cell markers. Lastly, spheroids were co-cultured with Strep. mutans, a cariogenic bacterial resident in the oral cavity, and acutely exposed to vape. Co-culture with S. mutans did not significantly affect spheroid growth under the current experimental conditions or significantly change the expression patterns of proliferation and tumor initiation proteins. Future research will include tumorigenic assays and investigate how vape may induce carcinogenesis of the oral epithelium.

Satellite glial cells (SGCs) surround the cell bodies of neurons of the peripheral nervous system, including those of the sensory ganglia. Their close apposition to the neuronal soma allows for bi-directional communication between neurons and SGCs, which are thought to regulate neuronal activity. After nerve injury, SGCs in the dorsal root ganglia contribute to neuropathic pain. Although the mechanisms are not fully understood, SGCs show increased coupling via gap junctions, and communicate with the neuron via bi-directional purinergic signaling after nerve injury. The increased coupling between SGCs and neurons may have implications for chronic pain following peripheral nerve injury. In vivo studies suggest that injury through the administration of capsaicin to the sensory nerve endings causes SGCs to be activated and proliferate. We have shown that capsaicin treatment in an in vitro co-culture of sensory neurons and SGCs increased the expression of the proliferation marker, Ki-67 in the glia. Here, we examine whether purinergic signaling plays a role in the promotion of SGC proliferation.

No description available.