Thesis (Ph. D.)--University of Washington, 2002. / Vita. Includes bibliographical references (leaves 109-126).

Indiana University-Purdue University Indianapolis (IUPUI) / Even though the molecular events and pathways that underlie craniofacial development and morphogenesis are not fully understood, it is accepted that their orchestration is influenced by the interaction of genetic and environmental factors. Inbred mouse strains represent genetically homogenous groups of individuals. It is established that mice in one strain often differ quite remarkably from mice in other inbred strains. Those phenotypic differences make mice exceptional tools for the dissection of genetic factors that influence normal and abnormal craniofacial morphogenesis. While numerous investigations have focused on abnormal morphogenesis, a comprehensive study of normal craniometric morphology across multiple inbred strains of mice has not been previously performed. The Mouse Phenome Project, an international collaboration of investigators, was formed to systematically phenotype a collection of normal inbred mouse strains. The objectives of our studies were to determine and measure differences in quantitative mandibular traits/variables within and between different inbred mouse strains, and to assess sexual di1norphism through bilateral measuren1ents of the hemimandibles. These studies were a component of the Mouse Phenome Project to collect normal craniometric data from 12 genetically heterogeneous inbred strains utilizing digital images from equal numbers of female and male mice at 7 to 8 weeks of age. Our central hypothesis was that morphometric analysis of mandibular structures from genetically disparate inbred mouse strains would reveal quantifiable differences. The null hypothesis of no difference among the strains for 1nandibular measurements was rejected. Overall, CAST/Ei and MOLF/Ei were consistently small in size measured by body weight with small skeletal structures. There was no strong pattern of body weight and site of skeletal size in the mid and heavy weighted strains. Evidence of sexual dimorphism was supported. Overall, it appears males and females that have the least significance between them are in the DBA/2J strain, followed by A/J. The strain with the most significant difference between males and females is in the C3H/HeJ strain.

Indiana University-Purdue University Indianapolis (IUPUI) / Even though the molecular events and pathways that underlie craniofacial development and morphogenesis are not fully understood, it is accepted that their orchestration is influenced by the interaction of genetic and environmental factors. Inbred mouse strains represent genetically homogenous groups of individuals. It is established that mice in one strain often differ quite remarkably from mice in other inbred strains. Those phenotypic differences make mice exceptional tools for the dissection of genetic factors that influence normal and abnormal craniofacial morphogenesis. While numerous investigations have focused on abnormal morphogenesis, a comprehensive study of normal craniometric morphology across multiple inbred strains of mice has not been previously performed. The Mouse Phenome Project, an international collaboration of investigators, was formed to systematically phenotype a collection of normal inbred mouse strains. The objectives of our studies were to determine and measure differences in quantitative mandibular traits/variables within and between different inbred mouse strains, and to assess sexual dimorphism through bilateral measurements of the hemimandibles. These studies were a component of the Mouse Phenome Project to collect normal craniometric data from 12 genetically heterogeneous inbred strains utilizing digital images from equal numbers of female and male mice at 7 to 8 weeks of age. Our central hypothesis was that morphometric analysis of mandibular structures from genetically disparate inbred mouse strains would reveal quantifiable differences. The null hypothesis of no difference among the strains for mandibular measurements was rejected. Overall, CAST/Ei and MOLF/Ei were consistently small in size measured by body weight with small skeletal structures. There was no strong pattern of body weight and site of skeletal size in the mid and heavy weighted strains. Evidence of sexual dimorphism was supported. Overall, it appears males and females that have the least significance between them are in the DBA/2J strain, followed by A/J. The strain with the most significant difference between males and females is in the C3H/HeJ strain.

Thesis (Ph.D. in Pharmacology) -- University of Colorado Denver, 2008. / Typescript. Includes bibliographical references (leaves 121-149). Free to UCD Anschutz Medical Campus. Online version available via ProQuest Digital Dissertations;

Indiana University-Purdue University Indianapolis (IUPUI) / Fluoridation of community water supplies for the purpose of preventing dental caries remains one of the top 10 public health interventions of the last century. However, exposure (ingestion) of greater than optimal amounts of fluoride from a variety of sources has led to an increase in the prevalence of dental fluorosis. We propose that dental fluorosis represents a complex condition caused by environmental and genetic factors. Purpose: To assess the role of genetics in the pathogenesis of dental fluorosis using genetically separate inbred strains of mice. Methods: Twelve genealogically disparate strains of mice were treated with 0 ppm, 25 ppm, and 50 ppm of fluoride in their drinking water. Each mouse was given weekly dental fluorosis evaluations. After 60 days of treatment, femurs were collected for fluoride analysis. Mandibular incisors were isolated for quantitative light induced fluorescence (QLF) studies and fluoride analysis. Digital and 35 mm images were taken of all mouse incisors in order to apply and compare the Dean's Index and the modified Thylstrup and Fejerskov Index (TFI), both indices of dental fluorosis. Skeletal radiographs were taken on the euthanized mice and later examined for extra skeletal calcifications and other gross bony deformities. Results: Differences in dental fluorosis susceptibility/resistance were identified between the strains, ranging from mild, moderate, to severe dental fluorosis. Furthermore, we found clustering of strains into distinct phenotypic groups. The A/J mouse strain was highly susceptible, with a rapid onset and severe development of dental fluorosis compared with the other strains tested. The 129P3/J mouse strain was least affected with negligible dental fluorosis. From the skeletal radiographs, no gross skeletal lesions or evidence of bone dysplasia were noted. Similar body burden of fluoride, as judged from analysis of mineralized tissues, was seen in all strains despite differences in their predispositions to develop dental fluorosis. Both the Dean's and TF indices are useful for classifying the stage or severity of fluorosis in mice, and there are advantages to the use of digital images over conventional 35 mm slide images. Both indices correlate well with the amount of fluoride exposure during amelogenesis; however, these indices are not promising indicators of fluoride burden during amelogenesis. Conclusions: QLF proved to be an innovative and useful tool for the quantification of dental fluorosis. Furthermore, these observations support the role of a genetic component in the pathogenesis of fluorosis.

Indiana University-Purdue University Indianapolis (IUPUI) / External apical root resorption (EARR) is a common complication of orthodontic treatment. Genetic factors account for approximately 50% of the variation in EARR. Data have indicated variation in histological root resorption associated with orthodontic force (RRAOF) among different inbred strains of mice. Differences in expression of RANKL and OPG were investigated in two strains of mice with different susceptibility to RRAOF using irnmunohistochemistry. Increased localization of RANKL was detected in the tissues surrounding the root of the susceptible strain compared to the resistant strain and the controls. In contrast, increased localization of OPG was found in the tissues surrounding the roots in the resistant A/J strain compared to the susceptible DBA/2J strain. We conclude that differences in the expression of these key bone resorption mediators play a role in determining RRAOF susceptibility. Changes in serum TRAP 5b level in response to orthodontic force were investigated among female A/J, DBA/2J and BALB/cJ mice. The three strains differed in their TRAP positive cell numbers as well as their serum TRAP 5b level at baseline and when treated. A significant increase in the serum TRAP 5b level with treatment was only detected in the RRAOF susceptible DBA/2J strain, and not in RRAOF resistant strains. Our analysis indicates that differences in osteoclast/odontoclast activity play a role in susceptibility to RRAOF that is genetically determined. Serum TRAP 5b levels have a potential role in screening for individuals with greater susceptibility to root resorption. RRAOF was determined for male and female mice of the A/J, DBA/2J and BALB/cJ strains, as well as A/J x DBA/2J and A/J x BALB/cJ crosses. Sex differences were observed among the BALB/cJ strain only, with females more resistant to RRAOF when compared to males. Fis from the A/J x BALB/cJ cross were resistant suggesting that the A/J have dominant resistance alleles, while Fis from the A/J x DBA/2J cross had RRAOF intermediate between their parental A/J and DBA/2J mice, suggesting a polygenic trait. We concluded that the mode of inheritance of RRAOF in mice was polygenic in nature.

Ph.D. / Behavioral Neuroscience / The purpose of the research described in this dissertation was to determine the neural circuits involved with baseline ethanol consumption and increases in ethanol consumption seen in our animal model of ethanol dependency (further described below). The brain region of focus was the central extended amygdala (cEA) since this region has been shown to be involved in baseline consumption and self-administration of ethanol in rats (Hyytia & Koob, 1995; Eiler et al., 2002) and the changes in ethanol consumption induced by chronic intermittent ethanol vapor exposure seen in rats and mice (Funk et al., 2006; Finn et al., 2007). To determine if the cEA is involved in these behavioral phenotypes, the components of the cEA were lesioned separately. These components included the lateral posterior portion of the bed nucleus of the stria terminalis (BNSTLP), the central nucleus of the amygdala (CeA) and the nucleus accumbens shell (NAc shell). Chapter 2 illustrates that lesions of the BNSTLP decreased baseline ethanol consumption in a 2 hr limited access procedure, but not in a continuous access procedure. Chapter 3 and chapter 4 illustrate that the CeA and NAc shell are involved in baseline ethanol consumption in a limited access procedure, since lesions of these nuclei decreased ethanol consumption. To determine if these nuclei were involved in increases in ethanol consumption, a murine model of ethanol dependency was used. In this procedure C57BL/6J (B6) mice are first acclimated to a limited access two-bottle choice preference procedure. The access period begins 3 hrs into the dark-cycle and continues for 2 hrs. Once acclimated, mice undergo chronic exposure to and intermittent withdrawal from ethanol vapor. Results from chapter 4 indicate that intermittent vapor exposure, as opposed to continuous ethanol vapor exposure, optimizes the increased ethanol x consumption response. As indicated in chapter 2, 3, and 4, lesions of these three components of the cEA did not block the intermittent ethanol vapor induced increase in ethanol consumption. In chapter 4, to determine the brain regions that activate in response to increases in ethanol consumption, a c-fos immunoreactivity study was carried out. The results suggest that the NAc shell and NAc core are the two main brain regions that activate as a result of ethanol consumption specifically in the mice that have been exposed to the intermittent ethanol vapor exposure that show the increase in ethanol consumption. Thus the results suggest that while the NAc shell activates in response to heightened levels of ethanol consumption, it is not necessary to see this increase in ethanol consumption. Overall, the results from these three chapters suggest that while the components of the cEA are involved in baseline ethanol consumption, and are responsive to changes in ethanol consumption (as was the case with the NAc shell), they are not necessary to see the ethanol vapor induced increase in ethanol consumption. These results have implications for understanding the neural circuitry involved in ethanol dependence.

Interferon regulatory factor-8 (Irf-8), a hematopoietic transcriptional regulator, controls myeloid-cell proliferation and coordinates innate and adaptive host immune responses. Mice from the BXH-2 recombinant inbred strain carry an endogenous R294C mutation in Irf-8. This loss-of-function mutation induces clonal infiltration of undifferentiated Mac-1+/Gr-1 + granulocytic precursors in BXH-2 mice, extramedullary hematopoiesis, and splenomegaly similar to those seen in human chronic myeloid leukemia. It also renders the host permissible to the otherwise avirulent Mycobacterium bovis (BCG), and negatively affects survival or recovery of these mice to other infectious pathogens. Here, we generated a polyc1onal anti-Irf-8 antibody to better characterize the effects of the R294C mutation on Irf-8 protein expression, stability, and inducibility in hematopoietic and non-hematopoietic tissues. We found that mutant Irf-8C294-expressing tissues consistently displayed reduced Irf-8 abundance compared to their wild-type counterparts in both primary splenocytes and following transfection into heterologous cells, presumably due to decreased stability or increased rate of degradation of the mutant isoform. Results also indicate that native Irf-8 is also expressed in the heart, and to a lesser extent, in the kidneys. Since neither of these organs is well-known to be associated with hematopoietic or immune functions, this finding strengthens the possibility that Irf-8 may exert additional regulatory functions in other cellular contexts. Taken together, our study provides a better understanding about the molecular features of the mutant Irf-8 C294 protein and contributes to a growing body of evidence in support of Irf-8 expression in non-hematopoietic tissues.

No description available.