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• 581. [Article] Prostate cancer prevention with broccoli : from cellular to human studies

  Prostate cancer is the second leading cause of cancer related death in American men. Epidemiologic studies suggest that cruciferous vegetable intake may lower the risk for many cancers, including prostate ...

  Citation × Citation Citation Abstract Copy Title: Prostate cancer prevention with broccoli : from cellular to human studies Author: Clarke, John D. Prostate cancer is the second leading cause of cancer related death in American men. Epidemiologic studies suggest that cruciferous vegetable intake may lower the risk for many cancers, including prostate and colon. Isothiocyanates (ITC) are phytochemicals derived from cruciferous vegetables such as broccoli, Brussels sprouts, cauliflower, and cabbage that may have health promoting properties. Broccoli and broccoli sprouts are a good source of sulforaphane (SFN), a well studied chemopreventive ITC. SFN is known to inhibit histone deacetylase (HDAC) activity and alter epigenetic endpoints. A key factor in understanding the efficacy of SFN as a chemoprevention agent is to determine the metabolism, distribution and bioavailability of SFN, and the factors that alter these parameters. The present study was undertaken to provide further evidence that SFN can alter HDAC activity, alter prostate cancer cell proliferation, both in vitro and in vivo and expands our understanding of SFN metabolism and tissue distribution. We characterized the effects of SFN in normal (PrEC), benign hyperplasia (BPH1) and cancerous (LnCap and PC3) prostate epithelial cells. We observed that 15 µM SFN differentially induced cell cycle arrest and apoptosis in BPH1, LnCap and PC3 cells but not PrEC cells. SFN treatment also differentially decreased HDAC activity, and Class I and II HDAC proteins, increased acetylated histone H3 at the promoter for P21, induced p21 expression and increased tubulin acetylation in prostate cancer cells. In PrEC cells, SFN caused only a transient reduction in HDAC activity with no change in any other endpoints tested. Therefore, normal prostate cells were refractory to the cytotoxic and epigenetic effects of SFN. In order for SFN to be an effective chemopreventive agent it must be metabolized and reach target tissues. Nrf2 wild-type and Nrf2 knockout (Nrf2-/-) mice were treated with 5 or 20 µmoles of SFN, and SFN metabolites were detected in all tissues tested at 2 and 6 h in a dose dependent manner. Genotype only had marginal effects at 5 µmoles, whereas, at 20 µmoles the female Nrf2-/- mice had dramatically higher levels. The relative abundance of each metabolite was not strikingly different between genders and genotypes, although different ratios between tissues were observed. In the transgenic adenoma of the mouse prostate model dietary SFN, fed as freeze-dried broccoli sprouts, increased SFN content in the prostate and decreased the severity of prostate cancer at 12 and 28 weeks of age. In humans, the differences in metabolism of isothiocyanates between whole food and broccoli supplements have yet to be determined. Two separate human trials were conducted; the first was a randomized 7 day feeding study where subjects consumed either broccoli sprouts or a broccoli supplement, and the second study was a randomized single dose cross-over study with broccoli sprouts, followed by a washout period, then broccoli supplement. In plasma and urine, the total amounts of SFN and erucin (ERN) metabolites were greater and the peak concentration occurred sooner in subjects who consumed broccoli sprouts. Glutathione-S-transferase pi-1 polymorphisms did not affect ITC metabolism. Interconversion of SFN to ERN was observed. Histone deacetylase activity in peripheral blood mononuclear cells was inhibited only in subjects who consumed sprouts. In conclusion, these data provide evidence that SFN alters HDAC activity and protein acetylation in cancerous prostate cells but not normal prostate cells. For the first time we show that SFN is bioavailable to many tissues types, including the prostate and are largely found as SFN metabolites not the parent SFN compound. We also show that the bioavailability of ITCs is markedly lower in human subjects who consume a broccoli supplement. Decreased HDAC activity in the peripheral blood of subjects who consumed sprouts indicates that higher ITC plasma concentrations can alter HDAC activity in vivo. Taken together, these data show that SFN is an effective prostate cancer chemopreventive agent that can easily be utilized in the diet from whole food. Title: Prostate cancer prevention with broccoli : from cellular to human studies Author: Clarke, John D. Prostate cancer is the second leading cause of cancer related death in American men. Epidemiologic studies suggest that cruciferous vegetable intake may lower the risk for many cancers, including prostate and colon. Isothiocyanates (ITC) are phytochemicals derived from cruciferous vegetables such as broccoli, Brussels sprouts, cauliflower, and cabbage that may have health promoting properties. Broccoli and broccoli sprouts are a good source of sulforaphane (SFN), a well studied chemopreventive ITC. SFN is known to inhibit histone deacetylase (HDAC) activity and alter epigenetic endpoints. A key factor in understanding the efficacy of SFN as a chemoprevention agent is to determine the metabolism, distribution and bioavailability of SFN, and the factors that alter these parameters. The present study was undertaken to provide further evidence that SFN can alter HDAC activity, alter prostate cancer cell proliferation, both in vitro and in vivo and expands our understanding of SFN metabolism and tissue distribution. We characterized the effects of SFN in normal (PrEC), benign hyperplasia (BPH1) and cancerous (LnCap and PC3) prostate epithelial cells. We observed that 15 µM SFN differentially induced cell cycle arrest and apoptosis in BPH1, LnCap and PC3 cells but not PrEC cells. SFN treatment also differentially decreased HDAC activity, and Class I and II HDAC proteins, increased acetylated histone H3 at the promoter for P21, induced p21 expression and increased tubulin acetylation in prostate cancer cells. In PrEC cells, SFN caused only a transient reduction in HDAC activity with no change in any other endpoints tested. Therefore, normal prostate cells were refractory to the cytotoxic and epigenetic effects of SFN. In order for SFN to be an effective chemopreventive agent it must be metabolized and reach target tissues. Nrf2 wild-type and Nrf2 knockout (Nrf2-/-) mice were treated with 5 or 20 µmoles of SFN, and SFN metabolites were detected in all tissues tested at 2 and 6 h in a dose dependent manner. Genotype only had marginal effects at 5 µmoles, whereas, at 20 µmoles the female Nrf2-/- mice had dramatically higher levels. The relative abundance of each metabolite was not strikingly different between genders and genotypes, although different ratios between tissues were observed. In the transgenic adenoma of the mouse prostate model dietary SFN, fed as freeze-dried broccoli sprouts, increased SFN content in the prostate and decreased the severity of prostate cancer at 12 and 28 weeks of age. In humans, the differences in metabolism of isothiocyanates between whole food and broccoli supplements have yet to be determined. Two separate human trials were conducted; the first was a randomized 7 day feeding study where subjects consumed either broccoli sprouts or a broccoli supplement, and the second study was a randomized single dose cross-over study with broccoli sprouts, followed by a washout period, then broccoli supplement. In plasma and urine, the total amounts of SFN and erucin (ERN) metabolites were greater and the peak concentration occurred sooner in subjects who consumed broccoli sprouts. Glutathione-S-transferase pi-1 polymorphisms did not affect ITC metabolism. Interconversion of SFN to ERN was observed. Histone deacetylase activity in peripheral blood mononuclear cells was inhibited only in subjects who consumed sprouts. In conclusion, these data provide evidence that SFN alters HDAC activity and protein acetylation in cancerous prostate cells but not normal prostate cells. For the first time we show that SFN is bioavailable to many tissues types, including the prostate and are largely found as SFN metabolites not the parent SFN compound. We also show that the bioavailability of ITCs is markedly lower in human subjects who consume a broccoli supplement. Decreased HDAC activity in the peripheral blood of subjects who consumed sprouts indicates that higher ITC plasma concentrations can alter HDAC activity in vivo. Taken together, these data show that SFN is an effective prostate cancer chemopreventive agent that can easily be utilized in the diet from whole food. 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• 582. [Article] Does Disability Severity Matter? The Daily Lives of Parent Caregivers of Children with Developmental Disabilities

  Individuals with disabilities and their parents, even within specific disability diagnoses, have diverse life experiences and trajectories. The current study focuses on parents of individuals with developmental ...

  Citation × Citation Citation Abstract Copy Title: Does Disability Severity Matter? The Daily Lives of Parent Caregivers of Children with Developmental Disabilities Author: Fenn, Meghann L. Individuals with disabilities and their parents, even within specific disability diagnoses, have diverse life experiences and trajectories. The current study focuses on parents of individuals with developmental disabilities. Developmental disabilities (DD) are a diverse group of severe chronic conditions evident at birth or acquired during childhood that affect major life activities such as language, mobility, learning, self-help, and independent living; and include conditions such as Down syndrome, attention deficit hyperactive disorder (ADHD), autism spectrum disorders, and general developmental delays. This study builds on previous literature concerning stress, caregiving, and disability by examining the daily lives, experiences, and wellbeing of parents of children with DD. The majority of health and wellbeing research being done in this area focuses on overall or global wellbeing. Comparatively little research has examined the daily lives, experiences, and wellbeing of these parents, who exist within extremely fluid contexts that change daily. Furthermore, this study also aims to build on previous research by considering the severity of the child’s disability, in order to further contextualize and understand the complex levels of influence within these parents’ daily lives. Using data from the second wave of the National Study of Daily Experiences (NSDE), the daily diary project of the National Survey of Midlife in the United States (MIDUS), this study examined these topics further by answering three specific research questions; First, to what extent does the association between daily stressors and same-day positive and negative affect differ for parents of children with and without DD? Second, to what extent does the association between daily positive events and same-day positive and negative affect differ for parents of children with and without DD? And lastly, are these associations further moderated by the severity of the child’s disability? A total of 82 participants (Mean Age = 57.4; 59% female, 96% non-Hispanic White, 79% married, Mean Education = 14 years) were identified as parents of children with DD. A sample of 82 individuals who were parents of typically developing children were identified and matched as a comparison group based on: parent gender, parent age, number of children in the household, child age, whether the target child lives with the parent, parent marital status, and parent educational attainment. Participants completed 8 nightly telephone interviews, which included assessments of their daily stressors and positive events, as well as positive and negative affect. Results from the current study found that the daily lives of individuals with disabilities and their parents are diverse and complex. Compared to their matched counterparts, parents of children with DD experienced significantly greater increases in negative affect associated with the experience of daily stressors. In contract, parents of children with DD exhibited comparable increases in daily positive affect associated with the daily positive experiences. With respect to severity of disability, the longevity of the child’s disability diagnosis, the number of comorbid disability diagnoses, and the number of comorbid mental health diagnoses, did selectively moderate daily experience-wellbeing associations, but not in a symmetric fashion across indicators. Taken together, the daily experiences and daily wellbeing of parents caring for a child with a disability cannot be understood and defined merely by knowing their child’s disability status. Parents of children with DD may be vulnerable because of the chronic stress context of caring for a child with a disability, and they show more reactive patterns of daily wellbeing when experiencing daily stressors, however, they also show resiliency in their daily wellbeing when experiencing daily positive events. The current study attempted to better contextualize and understand the daily lives of caregiving parents by moving beyond a binary definition of disability (yes/no a disability is present), and findings suggest that severity of disability is a complex phenomenon in need of continued empirical investigation. Title: Does Disability Severity Matter? The Daily Lives of Parent Caregivers of Children with Developmental Disabilities Author: Fenn, Meghann L. Individuals with disabilities and their parents, even within specific disability diagnoses, have diverse life experiences and trajectories. The current study focuses on parents of individuals with developmental disabilities. Developmental disabilities (DD) are a diverse group of severe chronic conditions evident at birth or acquired during childhood that affect major life activities such as language, mobility, learning, self-help, and independent living; and include conditions such as Down syndrome, attention deficit hyperactive disorder (ADHD), autism spectrum disorders, and general developmental delays. This study builds on previous literature concerning stress, caregiving, and disability by examining the daily lives, experiences, and wellbeing of parents of children with DD. The majority of health and wellbeing research being done in this area focuses on overall or global wellbeing. Comparatively little research has examined the daily lives, experiences, and wellbeing of these parents, who exist within extremely fluid contexts that change daily. Furthermore, this study also aims to build on previous research by considering the severity of the child’s disability, in order to further contextualize and understand the complex levels of influence within these parents’ daily lives. Using data from the second wave of the National Study of Daily Experiences (NSDE), the daily diary project of the National Survey of Midlife in the United States (MIDUS), this study examined these topics further by answering three specific research questions; First, to what extent does the association between daily stressors and same-day positive and negative affect differ for parents of children with and without DD? Second, to what extent does the association between daily positive events and same-day positive and negative affect differ for parents of children with and without DD? And lastly, are these associations further moderated by the severity of the child’s disability? A total of 82 participants (Mean Age = 57.4; 59% female, 96% non-Hispanic White, 79% married, Mean Education = 14 years) were identified as parents of children with DD. A sample of 82 individuals who were parents of typically developing children were identified and matched as a comparison group based on: parent gender, parent age, number of children in the household, child age, whether the target child lives with the parent, parent marital status, and parent educational attainment. Participants completed 8 nightly telephone interviews, which included assessments of their daily stressors and positive events, as well as positive and negative affect. Results from the current study found that the daily lives of individuals with disabilities and their parents are diverse and complex. Compared to their matched counterparts, parents of children with DD experienced significantly greater increases in negative affect associated with the experience of daily stressors. In contract, parents of children with DD exhibited comparable increases in daily positive affect associated with the daily positive experiences. With respect to severity of disability, the longevity of the child’s disability diagnosis, the number of comorbid disability diagnoses, and the number of comorbid mental health diagnoses, did selectively moderate daily experience-wellbeing associations, but not in a symmetric fashion across indicators. Taken together, the daily experiences and daily wellbeing of parents caring for a child with a disability cannot be understood and defined merely by knowing their child’s disability status. Parents of children with DD may be vulnerable because of the chronic stress context of caring for a child with a disability, and they show more reactive patterns of daily wellbeing when experiencing daily stressors, however, they also show resiliency in their daily wellbeing when experiencing daily positive events. The current study attempted to better contextualize and understand the daily lives of caregiving parents by moving beyond a binary definition of disability (yes/no a disability is present), and findings suggest that severity of disability is a complex phenomenon in need of continued empirical investigation. Close

• 583. [Article] A comparative analysis of factors influencing smoking behaviors of college students, 1963-1987

  Cigarette smoking continues to be one of the country's major health concerns. It has been defined as the single largest preventable cause of disease and death in the United States. Although research has ...

  Citation × Citation Citation Abstract Copy Title: A comparative analysis of factors influencing smoking behaviors of college students, 1963-1987 Author: Gray, Nancy L. Cigarette smoking continues to be one of the country's major health concerns. It has been defined as the single largest preventable cause of disease and death in the United States. Although research has indicated that overall cigarette consumption has decreased in the nation over the past decades, cigarette smoking remains a significant problem among young people in the United States. This fact, coupled with studies indicating that cigarette smoking increases with age into the early twenties suggests that research should be conducted to determine those variables that encourage smoking behavior of late adolescents and young adults. The purpose of the study was to compare the relationship between selected predisposing factors and subsequent smoking behaviors exhibited in 1963 and 1987 respectively. Assessments of smoking behaviors of college students in Oregon in 1963-64 and 1986-87 were conducted to determine relationships between students smoking behaviors and selected socio-demographic variables. Comparisons were made between the resulting data for students in the 1963-64and 1986-87 studies. Aquestionnaire relating to smoking behavior was developed and administered to 3,786 college students attending introductory personal health classes during the 1963-64 school year at four selected colleges in the state of Oregon. During the 1986-87 school year a modified version of the questionnaire was developed and administered to college students attending introductory personal health classes at three of the same four universities that were utilized in the 1963-64 study. Stepwise logistic regression, chi square and descriptive statistics were used to analyze the data. Results indicated that there were significantly more smokers in 1963-64 and their daily consumption rates were significantly higher when compared to 1986-87 data. Although a larger percentage of females were smokers in the total population surveyed in 1963-64, there were more female smokers in the population of smokers in 1986-87. Whereas males consumed significantly more cigarettes per day than did females in 1963-64, there was no significant difference between male and female consumption rates in 1986-87. Significant numbers of smokers in 1986-87 started smoking at an earlier age than did smokers in 1963-64. When separating by gender, this was significant for females but not for males. Peer smoking was listed as the number one reason for starting to smoke by more than half of the respondents in 1986-87 as compared to 40% who listed curiosity in 1963-64. Physical reasons were indicated as the main reason for quitting by ex-smokers in 1963-64 and in 1986-87, over one half of the respondents indicated that they quit because of a concern for their physical health. Stepwise logistic regression equations were used to determine the set of variables that best accounted for smoking status in 1963-64 and 1986-87. Results indicated that the variables which predisposed individuals toward subsequent smoking behavior did differ when comparing the two studies. In 1963-64, an individual with the highest probability of smoking was one who had one or more older sisters who smoked, both parents smoked, father was a high school non-graduate and was from an urban setting. The individual with the lowest probability of smoking in 1963-64 had no older sisters who smoked, mother and father did not smoke, father was a high school graduate and lived in a rural setting. In 1986-87, the only variable to significantly increase the probability of an individual smoking was one or more older brothers who smoked. The following data were collected only for the 1986-87 population of students because questions relating to these issues were not included on the 1963-64 questionnaire. Use of alcohol, marijuana and smokeless tobacco by cigarette smokers was not significantly different when compared to non-smokers. Illicit substance use (cocaine, crack, heroin, quaaludes, etc) was significantly different for cigarette smokers and non-smokers. Smokers were more likely to use illicit substances than were non-smokers. The largest number of smokeless tobacco users were males in the 18-19 age category. Use of alcohol, marijuana and other illicit substances were significantly different for smokeless tobacco users than for non-users. Smokeless tobacco users were more likely to consume more alcohol on a weekly basis and use marijuana and illicit substances on an occasional and regular basis than were non-users of smokeless tobacco. Title: A comparative analysis of factors influencing smoking behaviors of college students, 1963-1987 Author: Gray, Nancy L. Cigarette smoking continues to be one of the country's major health concerns. It has been defined as the single largest preventable cause of disease and death in the United States. Although research has indicated that overall cigarette consumption has decreased in the nation over the past decades, cigarette smoking remains a significant problem among young people in the United States. This fact, coupled with studies indicating that cigarette smoking increases with age into the early twenties suggests that research should be conducted to determine those variables that encourage smoking behavior of late adolescents and young adults. The purpose of the study was to compare the relationship between selected predisposing factors and subsequent smoking behaviors exhibited in 1963 and 1987 respectively. Assessments of smoking behaviors of college students in Oregon in 1963-64 and 1986-87 were conducted to determine relationships between students smoking behaviors and selected socio-demographic variables. Comparisons were made between the resulting data for students in the 1963-64and 1986-87 studies. Aquestionnaire relating to smoking behavior was developed and administered to 3,786 college students attending introductory personal health classes during the 1963-64 school year at four selected colleges in the state of Oregon. During the 1986-87 school year a modified version of the questionnaire was developed and administered to college students attending introductory personal health classes at three of the same four universities that were utilized in the 1963-64 study. Stepwise logistic regression, chi square and descriptive statistics were used to analyze the data. Results indicated that there were significantly more smokers in 1963-64 and their daily consumption rates were significantly higher when compared to 1986-87 data. Although a larger percentage of females were smokers in the total population surveyed in 1963-64, there were more female smokers in the population of smokers in 1986-87. Whereas males consumed significantly more cigarettes per day than did females in 1963-64, there was no significant difference between male and female consumption rates in 1986-87. Significant numbers of smokers in 1986-87 started smoking at an earlier age than did smokers in 1963-64. When separating by gender, this was significant for females but not for males. Peer smoking was listed as the number one reason for starting to smoke by more than half of the respondents in 1986-87 as compared to 40% who listed curiosity in 1963-64. Physical reasons were indicated as the main reason for quitting by ex-smokers in 1963-64 and in 1986-87, over one half of the respondents indicated that they quit because of a concern for their physical health. Stepwise logistic regression equations were used to determine the set of variables that best accounted for smoking status in 1963-64 and 1986-87. Results indicated that the variables which predisposed individuals toward subsequent smoking behavior did differ when comparing the two studies. In 1963-64, an individual with the highest probability of smoking was one who had one or more older sisters who smoked, both parents smoked, father was a high school non-graduate and was from an urban setting. The individual with the lowest probability of smoking in 1963-64 had no older sisters who smoked, mother and father did not smoke, father was a high school graduate and lived in a rural setting. In 1986-87, the only variable to significantly increase the probability of an individual smoking was one or more older brothers who smoked. The following data were collected only for the 1986-87 population of students because questions relating to these issues were not included on the 1963-64 questionnaire. Use of alcohol, marijuana and smokeless tobacco by cigarette smokers was not significantly different when compared to non-smokers. Illicit substance use (cocaine, crack, heroin, quaaludes, etc) was significantly different for cigarette smokers and non-smokers. Smokers were more likely to use illicit substances than were non-smokers. The largest number of smokeless tobacco users were males in the 18-19 age category. Use of alcohol, marijuana and other illicit substances were significantly different for smokeless tobacco users than for non-users. Smokeless tobacco users were more likely to consume more alcohol on a weekly basis and use marijuana and illicit substances on an occasional and regular basis than were non-users of smokeless tobacco. Close

• 584. [Article] Label-free mass spectrometry-driven methods for elucidating adaptive responses of the hepatic mitochondrial proteome in an alcoholic fatty liver disease model

  Alcoholic liver disease (ALD) continues to be one of the major public health problems in the United States and worldwide. Complicated by factors including gender, polymorphisms of alcohol-metabolizing ...

  Citation × Citation Citation Abstract Copy Title: Label-free mass spectrometry-driven methods for elucidating adaptive responses of the hepatic mitochondrial proteome in an alcoholic fatty liver disease model Author: Tzeng, Shin-Cheng Alcoholic liver disease (ALD) continues to be one of the major public health problems in the United States and worldwide. Complicated by factors including gender, polymorphisms of alcohol-metabolizing enzymes, immunologic factors, exposures to other substances/drugs, hepatic viral infections, nutritional deficiencies, and obesity, ALD is a complex disease that requires a systematic approach to dissect the mechanisms associated with organ dysfunction. Mechanistic knowledge is necessary to shed light on routes that potentially may lead to effective treatments. Proteomics as a discovery tool that may reveal new targets and pathways that can potentially be exploited for developing new preventive strategies and treatments. The mitochondrion is the pivotal organelle linked to disease progression and to the development of ALD. Studies have shown links between mitochondrial dysfunction and ethanol-induced liver injury, but the underlying mechanisms at the molecular level still remain largely unknown. In the present study we evaluated the capability of two label-free mass-spectrometry-driven approaches (i) the intensity-based MS[superscript E] method, and (ii) a spectral counting-based method that uses data-dependent acquisition (DDA). Initially a single- and a three-protein model system were utilized to evaluate differences in the performance characteristics of the two methods. To examine the performance difference of the two methods for proteome characterization, we measured changes in protein levels as a consequence of chronic alcohol consumption in rat liver mitochondria. Our results revealed that the MS[superscript E] approach had better performance in terms of precision, and dynamic range and resulted in superior accuracy for fold change determinations. The MS[superscript E] approach proved to identify more mitochondrial proteins than the two DDA methods. However, the run-to-run reproducibility of the MS[superscript E] method was lower than was observed for the DDA methods. Despite poor linear correlation between approaches, the outcomes of the proteome characterizations were rather consistent as more than half of the significantly altered proteins detected by the MS[superscript E] method were also revealed by at least one of the DDA methods. Collectively, we concluded that both MSE and DDA approaches provide satisfactory performance with the MS[superscript E] approach outperforming the DDA-based methods with respect to accuracy, linearity and dynamic range. Further, we integrated the label-free LC-MS[superscript E] quantification with bioinformatics and knowledge base to profile alteration of the mitochondrial proteome for unraveling the protective effect of MitoQ, a mitochondrial targeted ubiquinone, on ALD. With carefully maintained stability of the LC-MS system, robust proteome datasets with high technical precision were obtained. By taking advantage of the information-rich quantitative proteomic data, we quantitatively categorized the identified proteins and performed pathway analysis for each category independently. Metabolic pathways and associated proteins were highlighted with the guidance of the systems biology approach. In summary, our results indicated that the pathways enriched in response to MitoQ included acyl-CoA synthases and the carnitine shuttle, ketogenesis, the TCA cycle and oxidative phosphorylation. The MitoQ-responsive metabolic network suggested that MitoQ up-regulates fatty acid transportation to counteract accumulation of lipids in the fatty liver. For dissecting the mitochondrial proteome, we develop a "targeted" quantitative approach involving label-free mass spectrometry-based quantification, chemoselective labeling, avidin- biotin based affinity enrichment at both protein and peptide level. The approach was applied to mitochondria exposed to 4-hydroxy-2-nonenal (HNE) for depicting a subset of the mitochondrial proteome susceptible to HNE insult. The utilization of the carbonyl-selective probe, ARP, facilitated labeling of HNE-adducted proteins and enabled avidin affinity enrichment with the biotin moiety. A list of potential protein targets with concentration-dependent response and known HNE modification sites was obtained when combining results from the protein- and peptide-level enrichment workflows. The core list of putative protein targets of HNE adduction may serve as lead for further validation studies towards unraveling the pathogenesis of ALD and emerging treatment modalities using Western blotting or targeted LC-MS methods. Title: Label-free mass spectrometry-driven methods for elucidating adaptive responses of the hepatic mitochondrial proteome in an alcoholic fatty liver disease model Author: Tzeng, Shin-Cheng Alcoholic liver disease (ALD) continues to be one of the major public health problems in the United States and worldwide. Complicated by factors including gender, polymorphisms of alcohol-metabolizing enzymes, immunologic factors, exposures to other substances/drugs, hepatic viral infections, nutritional deficiencies, and obesity, ALD is a complex disease that requires a systematic approach to dissect the mechanisms associated with organ dysfunction. Mechanistic knowledge is necessary to shed light on routes that potentially may lead to effective treatments. Proteomics as a discovery tool that may reveal new targets and pathways that can potentially be exploited for developing new preventive strategies and treatments. The mitochondrion is the pivotal organelle linked to disease progression and to the development of ALD. Studies have shown links between mitochondrial dysfunction and ethanol-induced liver injury, but the underlying mechanisms at the molecular level still remain largely unknown. In the present study we evaluated the capability of two label-free mass-spectrometry-driven approaches (i) the intensity-based MS[superscript E] method, and (ii) a spectral counting-based method that uses data-dependent acquisition (DDA). Initially a single- and a three-protein model system were utilized to evaluate differences in the performance characteristics of the two methods. To examine the performance difference of the two methods for proteome characterization, we measured changes in protein levels as a consequence of chronic alcohol consumption in rat liver mitochondria. Our results revealed that the MS[superscript E] approach had better performance in terms of precision, and dynamic range and resulted in superior accuracy for fold change determinations. The MS[superscript E] approach proved to identify more mitochondrial proteins than the two DDA methods. However, the run-to-run reproducibility of the MS[superscript E] method was lower than was observed for the DDA methods. Despite poor linear correlation between approaches, the outcomes of the proteome characterizations were rather consistent as more than half of the significantly altered proteins detected by the MS[superscript E] method were also revealed by at least one of the DDA methods. Collectively, we concluded that both MSE and DDA approaches provide satisfactory performance with the MS[superscript E] approach outperforming the DDA-based methods with respect to accuracy, linearity and dynamic range. Further, we integrated the label-free LC-MS[superscript E] quantification with bioinformatics and knowledge base to profile alteration of the mitochondrial proteome for unraveling the protective effect of MitoQ, a mitochondrial targeted ubiquinone, on ALD. With carefully maintained stability of the LC-MS system, robust proteome datasets with high technical precision were obtained. By taking advantage of the information-rich quantitative proteomic data, we quantitatively categorized the identified proteins and performed pathway analysis for each category independently. Metabolic pathways and associated proteins were highlighted with the guidance of the systems biology approach. In summary, our results indicated that the pathways enriched in response to MitoQ included acyl-CoA synthases and the carnitine shuttle, ketogenesis, the TCA cycle and oxidative phosphorylation. The MitoQ-responsive metabolic network suggested that MitoQ up-regulates fatty acid transportation to counteract accumulation of lipids in the fatty liver. For dissecting the mitochondrial proteome, we develop a "targeted" quantitative approach involving label-free mass spectrometry-based quantification, chemoselective labeling, avidin- biotin based affinity enrichment at both protein and peptide level. The approach was applied to mitochondria exposed to 4-hydroxy-2-nonenal (HNE) for depicting a subset of the mitochondrial proteome susceptible to HNE insult. The utilization of the carbonyl-selective probe, ARP, facilitated labeling of HNE-adducted proteins and enabled avidin affinity enrichment with the biotin moiety. A list of potential protein targets with concentration-dependent response and known HNE modification sites was obtained when combining results from the protein- and peptide-level enrichment workflows. The core list of putative protein targets of HNE adduction may serve as lead for further validation studies towards unraveling the pathogenesis of ALD and emerging treatment modalities using Western blotting or targeted LC-MS methods. Close

• 585. [Article] Factors affecting within-season and between-season breeding dispersal of burrowing owls in California

  Dispersal is integral to our understanding of the life history and population biology of many vertebrates, but difficulties in detecting long distance movements have complicated its study. Moreover, studies ...

  Citation × Citation Citation Abstract Copy Title: Factors affecting within-season and between-season breeding dispersal of burrowing owls in California Author: Catlin, Daniel H. Dispersal is integral to our understanding of the life history and population biology of many vertebrates, but difficulties in detecting long distance movements have complicated its study. Moreover, studies of factors affecting dispersal are often unable to determine the relative contributions of variables such as nesting success, mate fidelity, and nest site fidelity. I examined the effects of nest depredation on dispersal in comparison to successful nests and nests that failed for other reasons. Additionally, I investigated a suite of biological factors affecting within-season and between-season breeding dispersal by burrowing owls (Athene cunicularia) in California, attempting to partition the effects of these covariates and to deal with long distance detectibility issues. For both types of dispersal, I divided dispersal into two components; dispersal probability and dispersal distance. I used experimental and observational approaches to investigate within-season dispersal in two contrasting environments; a large grassland and an agricultural landscape. I found that the factors affecting dispersal probability and dispersal distance were different, supporting my decision to examine each separately. Of the factors investigated, dispersal probability was influenced most by study area, mate fidelity, and nesting success. The proportion of individuals dispersing tended to be greater for owls that lost their mate due to death or dispersal (60%, 6 of 10) and owls whose nests were depredated (50%, 10 of 20) than for owls that did not lose their mates (33%, 6 of 18) and owls whose nests were successful (17%, 1 of 6), respectively. The results from an experiment where we removed eggs from pairs of owls to simulate nest depredation were consistent with the observational results, suggesting that owls whose nests were depredated may have been more likely to disperse than control owls. The reactions of owls from depredated nests, however, did not appear to differ from those whose nests failed for other reasons. In contrast, owl dispersal distance was most affected by owl gender, and to a lesser degree by study area and nesting success. Dispersal distance was greater for female owls (median = 1575 m, n = 13) than male owls (median = 417 m, n = 11), greater for owls from the grassland area (median= 939 m, n = 9) compared to owls from the agricultural area (median = 829 m, n = 15), and greater for owls whose nests had failed (median = 1018 m, n = 17) than for owls that successfully bred (median 475 m, n = 7). Nest depredation, however, did not appear to increase dispersal distance. The geometric models performed poorly at approximating within-season dispersal distance, indicating that many owls disperse farther than predicted by a "first is best" model. I speculate that the distribution of within-season dispersal distances by burrowing owls is related to the densities of suitable territories and mates, which are more variable than predicted by a geometric model within a breeding season. I used data from band resightings and nesting success (1998-2003) to examine factors related to between-season breeding dispersal by burrowing owls in an agricultural environment. Of the factors investigated, nesting success appeared to have the greatest effect on burrowing owl dispersal. The proportion of individuals dispersing was greater for owls whose nests had failed (68%, 28 of 41) than owls whose nests were successful (27%, 58 of 212). Similarly, dispersal distance was greater for owls whose nest failed (mean = 745 ± 175 m, n = 28) than owls with successful nests (mean = 340 ± 36 m,n = 58). The owls exhibited high rates of nest site and mate fidelity between breeding seasons. There was evidence that previous experience at a breeding site may have reduced dispersal probability and that unpaired owls may have been more likely to disperse and dispersed slightly greater distances than those that retained their mates. Nesting success, however, appeared to be the major factor contributing to burrowing owl breeding dispersal after controlling for nest site and mate fidelity, particularly for male owls. Despite the complexity of the dispersal process, a geometric model provided a reasonably good fit to the distribution of between-season breeding dispersal distances at relatively short distances, but failed to predict a small percentage of long distance dispersals. Geometric models appeared to be a better fit for the distribution of between-season breeding dispersal distances than within-season breeding dispersal distances. Factors affecting within-season dispersal were generally similar to those affecting between-season dispersal. Both within-season and between-season breeding dispersal were affected by nesting success and mate fidelity, but the effects of these factors differed between the two types of breeding dispersal, suggesting that time constraints and competition play a larger role in within-season dispersal than between season dispersal. In addition, both studies supported a difference in dispersal behavior, in which the factors that affected dispersal probability were distinct from those that affected dispersal distance. These results help determine the relative contributions of nesting success, mate fidelity, and nest site fidelity to avian dispersal, offer some evidence that the effects of nest depredation are not distinct from the effects of nest failure in general, and provide further support for the division of dispersal into dispersal probability and dispersal distance. Title: Factors affecting within-season and between-season breeding dispersal of burrowing owls in California Author: Catlin, Daniel H. Dispersal is integral to our understanding of the life history and population biology of many vertebrates, but difficulties in detecting long distance movements have complicated its study. Moreover, studies of factors affecting dispersal are often unable to determine the relative contributions of variables such as nesting success, mate fidelity, and nest site fidelity. I examined the effects of nest depredation on dispersal in comparison to successful nests and nests that failed for other reasons. Additionally, I investigated a suite of biological factors affecting within-season and between-season breeding dispersal by burrowing owls (Athene cunicularia) in California, attempting to partition the effects of these covariates and to deal with long distance detectibility issues. For both types of dispersal, I divided dispersal into two components; dispersal probability and dispersal distance. I used experimental and observational approaches to investigate within-season dispersal in two contrasting environments; a large grassland and an agricultural landscape. I found that the factors affecting dispersal probability and dispersal distance were different, supporting my decision to examine each separately. Of the factors investigated, dispersal probability was influenced most by study area, mate fidelity, and nesting success. The proportion of individuals dispersing tended to be greater for owls that lost their mate due to death or dispersal (60%, 6 of 10) and owls whose nests were depredated (50%, 10 of 20) than for owls that did not lose their mates (33%, 6 of 18) and owls whose nests were successful (17%, 1 of 6), respectively. The results from an experiment where we removed eggs from pairs of owls to simulate nest depredation were consistent with the observational results, suggesting that owls whose nests were depredated may have been more likely to disperse than control owls. The reactions of owls from depredated nests, however, did not appear to differ from those whose nests failed for other reasons. In contrast, owl dispersal distance was most affected by owl gender, and to a lesser degree by study area and nesting success. Dispersal distance was greater for female owls (median = 1575 m, n = 13) than male owls (median = 417 m, n = 11), greater for owls from the grassland area (median= 939 m, n = 9) compared to owls from the agricultural area (median = 829 m, n = 15), and greater for owls whose nests had failed (median = 1018 m, n = 17) than for owls that successfully bred (median 475 m, n = 7). Nest depredation, however, did not appear to increase dispersal distance. The geometric models performed poorly at approximating within-season dispersal distance, indicating that many owls disperse farther than predicted by a "first is best" model. I speculate that the distribution of within-season dispersal distances by burrowing owls is related to the densities of suitable territories and mates, which are more variable than predicted by a geometric model within a breeding season. I used data from band resightings and nesting success (1998-2003) to examine factors related to between-season breeding dispersal by burrowing owls in an agricultural environment. Of the factors investigated, nesting success appeared to have the greatest effect on burrowing owl dispersal. The proportion of individuals dispersing was greater for owls whose nests had failed (68%, 28 of 41) than owls whose nests were successful (27%, 58 of 212). Similarly, dispersal distance was greater for owls whose nest failed (mean = 745 ± 175 m, n = 28) than owls with successful nests (mean = 340 ± 36 m,n = 58). The owls exhibited high rates of nest site and mate fidelity between breeding seasons. There was evidence that previous experience at a breeding site may have reduced dispersal probability and that unpaired owls may have been more likely to disperse and dispersed slightly greater distances than those that retained their mates. Nesting success, however, appeared to be the major factor contributing to burrowing owl breeding dispersal after controlling for nest site and mate fidelity, particularly for male owls. Despite the complexity of the dispersal process, a geometric model provided a reasonably good fit to the distribution of between-season breeding dispersal distances at relatively short distances, but failed to predict a small percentage of long distance dispersals. Geometric models appeared to be a better fit for the distribution of between-season breeding dispersal distances than within-season breeding dispersal distances. Factors affecting within-season dispersal were generally similar to those affecting between-season dispersal. Both within-season and between-season breeding dispersal were affected by nesting success and mate fidelity, but the effects of these factors differed between the two types of breeding dispersal, suggesting that time constraints and competition play a larger role in within-season dispersal than between season dispersal. In addition, both studies supported a difference in dispersal behavior, in which the factors that affected dispersal probability were distinct from those that affected dispersal distance. These results help determine the relative contributions of nesting success, mate fidelity, and nest site fidelity to avian dispersal, offer some evidence that the effects of nest depredation are not distinct from the effects of nest failure in general, and provide further support for the division of dispersal into dispersal probability and dispersal distance. Close

• 586. [Article] Assessing equity in health system finance and health care utilization : the case of Chile, and a model to measure health care access

  Chile has experienced great success in terms of economic growth in the last decades. This growing economy brings changes in the Chilean health care system. Its health care system was primarily funded by ...

  Citation × Citation Citation Abstract Copy Title: Assessing equity in health system finance and health care utilization : the case of Chile, and a model to measure health care access Author: Nunez Mondaca, Alicia Lorena Chile has experienced great success in terms of economic growth in the last decades. This growing economy brings changes in the Chilean health care system. Its health care system was primarily funded by state sources until 1981, when a major reform was introduced that established new rules for the health insurance market. Since then, Chile has a public-private mixed health care system, both in financing and delivery of services. Citizens can choose for coverage between the Public National Health Insurance and the Private Health Insurance system. However, these systems have a common funding source coming from the mandatory contribution of employees, equivalent to 7% of their taxable income with an approximate limit of US$2,800 dollars. One of the more important Chilean health reforms towards the establishment of social guarantees was effective on July 2005, when the Regime of Explicit Health Guarantees, also known as Plan AUGE became effective. Plan AUGE is a health program that benefits all Chileans without discrimination of age, gender, economic status, health care, or place of residence. This plan includes the 69 diseases with higher impact on Chilean population in its different stages, but with feasibility of effective treatments. Changes in the health care system and its last reform brought questions about their impact on the distribution of health care services throughout country. Is Chile moving towards a better and more equitable health care system? The main purpose of this thesis is to investigate equity in health system finance and health care utilization as well as to explore alternative measurement of access to health care in Chile. The first two manuscripts examine equity issues in Chile. The purpose of the first one is to assess equity in health system finance in Chile, accounting for all finance sources. While equity in health system finance has been well studied in OECD countries, there are still few published empirical studies on Latin American health care systems, where there tends to be a wider gap in income-wealth distribution among states. This gap may increase the financial burden for people in the lower spectrum of income groups, which is the main concern in the first manuscript. It will focus on identifying policy variables that may contribute to more equitable distribution of the financial burden in health care. The equity principle we adopt for this study is the ability to pay principle. Based on this, we explore factors that contribute to inequities in the health care system finance and issues about who bears the heavier burden of out-of pocket (OOP) payment, progressivity of OOP payment, and the redistributive effect of OOP payment for health care as a source of finance in the Chilean health care system. Our analysis is based on data from the National Socioeconomic Survey (CASEN), and the 2006 National Survey on Satisfaction and OOP payments. Results from this study provide comprehensive understanding of the financial burden of health care in Chile. This study identified evidence of inequity, in spite of the progressivity of the health care system. Furthermore, our assessment of equity in health system finance identified relevant policy variables such as education, insurance system, and method of payment that should be taken into consideration in the ongoing debates and research in improving the Chilean system. Such findings will also benefit other Latin American countries that are concerned about equity in health system finance. The purpose of the second manuscript was to assess equity in health care utilization in Chile. Secondary data analyses from the National Socioeconomic Survey (CASEN) were performed to estimate the impact of different factors including AUGE in the utilization of health care services. We used a two-part model for the analysis of frequency of health care use in the country. Four other separate two-part models were also specified to estimate the frequency of use of preventive services, general practitioner services, specialty care and emergency care. An assessment of horizontal equity was also included. Results suggest the presence of pro-rich inequities in the use of medical care. The estimation of the two-part model found key factors affecting utilization of health care services such as education and the implementation of the AUGE program. These findings provide timely evidence to policy-makers to understand the current distribution and equity of health care utilization, and to strengthen availability of health services accordingly. The third manuscript was motivated by the previous findings. Its purpose was to explore an alternative measurement for health care access. The majority of studies nowadays use a single proxy to estimate access: the use of health care services. However, we saw many limitations on this approach since it only considers people that are already using the system and ignores those that are not. The final manuscript proposed a model to estimate access to health care services based on communitarian claims. The model identified barriers to health care access as well as the preferences of the community for priority settings. Title: Assessing equity in health system finance and health care utilization : the case of Chile, and a model to measure health care access Author: Nunez Mondaca, Alicia Lorena Chile has experienced great success in terms of economic growth in the last decades. This growing economy brings changes in the Chilean health care system. Its health care system was primarily funded by state sources until 1981, when a major reform was introduced that established new rules for the health insurance market. Since then, Chile has a public-private mixed health care system, both in financing and delivery of services. Citizens can choose for coverage between the Public National Health Insurance and the Private Health Insurance system. However, these systems have a common funding source coming from the mandatory contribution of employees, equivalent to 7% of their taxable income with an approximate limit of US$2,800 dollars. One of the more important Chilean health reforms towards the establishment of social guarantees was effective on July 2005, when the Regime of Explicit Health Guarantees, also known as Plan AUGE became effective. Plan AUGE is a health program that benefits all Chileans without discrimination of age, gender, economic status, health care, or place of residence. This plan includes the 69 diseases with higher impact on Chilean population in its different stages, but with feasibility of effective treatments. Changes in the health care system and its last reform brought questions about their impact on the distribution of health care services throughout country. Is Chile moving towards a better and more equitable health care system? The main purpose of this thesis is to investigate equity in health system finance and health care utilization as well as to explore alternative measurement of access to health care in Chile. The first two manuscripts examine equity issues in Chile. The purpose of the first one is to assess equity in health system finance in Chile, accounting for all finance sources. While equity in health system finance has been well studied in OECD countries, there are still few published empirical studies on Latin American health care systems, where there tends to be a wider gap in income-wealth distribution among states. This gap may increase the financial burden for people in the lower spectrum of income groups, which is the main concern in the first manuscript. It will focus on identifying policy variables that may contribute to more equitable distribution of the financial burden in health care. The equity principle we adopt for this study is the ability to pay principle. Based on this, we explore factors that contribute to inequities in the health care system finance and issues about who bears the heavier burden of out-of pocket (OOP) payment, progressivity of OOP payment, and the redistributive effect of OOP payment for health care as a source of finance in the Chilean health care system. Our analysis is based on data from the National Socioeconomic Survey (CASEN), and the 2006 National Survey on Satisfaction and OOP payments. Results from this study provide comprehensive understanding of the financial burden of health care in Chile. This study identified evidence of inequity, in spite of the progressivity of the health care system. Furthermore, our assessment of equity in health system finance identified relevant policy variables such as education, insurance system, and method of payment that should be taken into consideration in the ongoing debates and research in improving the Chilean system. Such findings will also benefit other Latin American countries that are concerned about equity in health system finance. The purpose of the second manuscript was to assess equity in health care utilization in Chile. Secondary data analyses from the National Socioeconomic Survey (CASEN) were performed to estimate the impact of different factors including AUGE in the utilization of health care services. We used a two-part model for the analysis of frequency of health care use in the country. Four other separate two-part models were also specified to estimate the frequency of use of preventive services, general practitioner services, specialty care and emergency care. An assessment of horizontal equity was also included. Results suggest the presence of pro-rich inequities in the use of medical care. The estimation of the two-part model found key factors affecting utilization of health care services such as education and the implementation of the AUGE program. These findings provide timely evidence to policy-makers to understand the current distribution and equity of health care utilization, and to strengthen availability of health services accordingly. The third manuscript was motivated by the previous findings. Its purpose was to explore an alternative measurement for health care access. The majority of studies nowadays use a single proxy to estimate access: the use of health care services. However, we saw many limitations on this approach since it only considers people that are already using the system and ignores those that are not. The final manuscript proposed a model to estimate access to health care services based on communitarian claims. The model identified barriers to health care access as well as the preferences of the community for priority settings. Close

• 587. [Article] Implications of cougar prey selection and demography on population dynamics of elk in northeast Oregon

  Mule deer (Odocoileus hemionus hemionus) and Rocky Mountain elk (Cervus canadensis nelsoni; hereafter elk) populations in northeast Oregon have declined in the past 10 to 20 years. Concurrent with these ...

  Citation × Citation Citation Abstract Copy Title: Implications of cougar prey selection and demography on population dynamics of elk in northeast Oregon Author: Clark, Darren A. Mule deer (Odocoileus hemionus hemionus) and Rocky Mountain elk (Cervus canadensis nelsoni; hereafter elk) populations in northeast Oregon have declined in the past 10 to 20 years. Concurrent with these declines, cougar (Puma concolor) populations have apparently increased, leading to speculation that predation by cougars may be responsible for declining ungulate populations. However, empirical data on cougar diets, kill rates, and prey selection are lacking to support this speculation. Furthermore, the common assumption that cougar populations have increased in northeast Oregon may not be well founded because cougar populations in other areas within the Pacific Northwest region have declined in recent years. My primary research objectives were to (1) estimate kill rates and prey selection by cougars in northeast Oregon, (2) document causes of mortality and estimate survival rates for cougars, (3) estimate population growth rates of cougars in northeast Oregon and simulate the effects of hypothetical lethal control efforts on the cougar population, and (4) investigate the relative influence of top-down, bottom-up, and climatic factors for limiting population growth rates of elk in northeast Oregon. Results from my research will help guide cougar and elk management in northeast Oregon and provide a framework for assessing relative effects of top-down, bottom-up, and abiotic factors on population growth rates of ungulates in this and other areas. I implemented a 3-year study in northeast Oregon to investigate diets, kill rates, and prey selection of cougars in a multiple-prey system to better understand mechanisms by which cougars may influence ungulate populations. During my research, 25 adult cougars were captured and fitted with Global Positioning System (GPS) collars to identify kill sites. I monitored predation sequences of these cougars for 7,642 days and located the remains of 1,213 prey items killed by cougars. Cougars killed ungulates at an average rate of 1.03 per week (95% CI = 0.92 – 1.14); however, ungulate kill rates were variable and influenced by the season and demographic classification of cougars. Cougars killed ungulates 1.55 (95% CI = 1.47 – 1.66) times more frequently during summer (May-Oct) than during winter (Nov-Apr), but killed similar amounts of ungulate biomass (8.05 kg/day; 95% CI = 6.74 – 9.35) throughout the year. Cougars killed ungulates more frequently in summer because juvenile ungulates comprised most of the diet and were smaller on average than ungulate prey killed in winter. Female cougars with kittens killed more frequently (kills/day) than males or solitary females. After accounting for the additional biomass of kittens in cougar family groups, male cougars killed on average more biomass of ungulate prey per day than did females (R = 0.41, P < 0.001), and female cougars killed more biomass of prey per day as a function of the number and age of their kittens (R = 0.60, P < 0.001). Patterns of prey selection were influenced by season and demographic classification of cougars. Female cougars selected elk calves during summer and deer fawns during winter. In contrast, male cougars selected elk calves and yearling elk during summer and elk calves during winter. My results strongly supported the hypothesis that cougar predation is influenced by season, gender, and reproductive status of the cougar and these patterns in cougar predation may be generalizable among ecosystems. The observed selection for juvenile elk and deer suggested a possible mechanism by which cougars could negatively affect population growth rates of ungulates. I investigated survival and documented causes of mortality for radio-collared cougars at 3 study areas in Oregon during 1989 – 2011. Mortality due to hunter harvest was the most common cause of death for cougars in the Catherine Creek study area and the study area combining Wenaha, Sled Springs, and Mt. Emily Wildlife Management Units (WSM study area) in northeast Oregon. In contrast, natural mortality was the most common cause of death for cougars in the Jackson Creek study area in southwest Oregon. Annual survival rates of adult males were lowest at Catherine Creek when it was legal to hunt cougars with dogs (Ŝ = 0.57), but increased following the prohibition of this hunting practice (Ŝ = 0.86). This latter survival rate was similar to those observed at Jackson Creek (Ŝ = 0.78) and WSM (Ŝ = 0.82). Regardless of whether hunting of cougars with dogs was permitted, annual survival rates of adult females were similar among study areas (Catherine Creek Ŝ = 0.86; WSM Ŝ = 0.85; Jackson Creek Ŝ = 0.85). I did not document an effect of age on cougar survival rates in the Catherine Creek study area, which I attributed to selective harvest of prime-aged, male cougars when it was legal to hunt cougars with dogs. In contrast, I observed an effect of age on annual survival in both the WSM and Jackson Creek study areas. These results indicate that sub-adult males had significantly lower survival rates than sub-adult females, but survival rates of males and females were similar by age 4 or 5 years. My results suggest that survival rates of cougars in areas where hunting cougars with dogs is illegal should be substantially higher than areas where use of dogs is legal. I used estimates of cougar vital rates from empirical data collected in northeast Oregon to parameterize a Leslie projection matrix model to estimate deterministic and stochastic population growth rates of cougars in northeast Oregon when hunting cougars with dogs was legal (1989 - 1994) and illegal (2002 - 2011). A model cougar population in northeast Oregon that was hunted with dogs increased at a mean stochastic growth rate of 21% per year (λ[subscript s] = 1.21). Similarly, I found that a model cougar population that was subjected to hunting without dogs increased at a rate of 17% per year (λ[subscript s] = 1.17). Given that hunting cougars with dogs typically results in increased harvest and reduced survival rates of cougars, it was unexpected that the cougar population subjected to hunting with dogs was increasing at a faster rate than one that was not hunted with dogs. However, cougar populations in Oregon were subjected to low harvest rates when hunting cougars with dogs was legal and harvest was male biased. This resulted in high survival rates of female cougars and correspondingly high population growth rates. The Oregon Cougar Management Plan allows the Oregon Department of Fish and Wildlife to administratively reduce cougar populations to benefit ungulate populations, reduce human-cougar conflicts, and limit livestock depredation. Consequently, I was interested in modeling the effects of a hypothetical lethal control effort on a local cougar population. Using empirically-derived vital rates and a deterministic Leslie matrix model, I found that the proportion of the cougar population that would need to be removed annually to achieve a 50% population reduction within 3 years was 28% assuming a closed population, and 48% assuming maximum immigration rates into the population. Using a stochastic Leslie matrix model, I also determined that the model cougar population would likely return to its pre-removal size in 6 years assuming a closed population, and 2 years assuming maximum immigration rates. These model results indicate that current management practices and harvest regulations, combined with short-term, intensive, and localized population reductions, are unlikely to negatively affect the short-term viability of cougar populations in northeast Oregon. However, at this time, it is not known if intensive lethal control efforts funded by state agencies will be cost-effective (i.e., increased sales of tags to hunt deer and elk will offset the costs of control efforts). Further research is needed to investigate the cost-effectiveness of cougar control efforts in Oregon. I developed a Leslie matrix population model, parameterized with empirically-derived vital rates for elk in northeast Oregon, to investigate the relative influence on elk population growth rates of (1) survival and pregnancy, and (2) top-down, bottom-up, and climatic variables. I then estimated the effect of varying the strength of top-down factors on growth rates of elk populations. Growth rates of the model elk population were most sensitive to changes in adult female survival, but due to the inherent empirical variation in juvenile survival rates explained the overwhelming majority of variation in model population growth rates (r² = 0.92). Harvest of female elk had a strong negative effect on model population growth rates of elk (r² = 0.63). An index of cougar density was inversely related to population growth rates of elk in my model (r² = 0.38). A delay in mean date of birth was associated with reduced juvenile survival, but this had a minimal effect on population growth rates in my model (r² = 0.06). Climatic variables, which were used as surrogates for nutritional condition of females, had minimal effects on population growth rates. Likewise, elk density had almost no effect on population growth rates (r² = 0.002). The results of my model provided a novel finding that cougars can be a strong limiting factor on elk populations. Wildlife managers should consider the potential top-down effects of cougars and other predators as a limiting factor on elk populations. Title: Implications of cougar prey selection and demography on population dynamics of elk in northeast Oregon Author: Clark, Darren A. Mule deer (Odocoileus hemionus hemionus) and Rocky Mountain elk (Cervus canadensis nelsoni; hereafter elk) populations in northeast Oregon have declined in the past 10 to 20 years. Concurrent with these declines, cougar (Puma concolor) populations have apparently increased, leading to speculation that predation by cougars may be responsible for declining ungulate populations. However, empirical data on cougar diets, kill rates, and prey selection are lacking to support this speculation. Furthermore, the common assumption that cougar populations have increased in northeast Oregon may not be well founded because cougar populations in other areas within the Pacific Northwest region have declined in recent years. My primary research objectives were to (1) estimate kill rates and prey selection by cougars in northeast Oregon, (2) document causes of mortality and estimate survival rates for cougars, (3) estimate population growth rates of cougars in northeast Oregon and simulate the effects of hypothetical lethal control efforts on the cougar population, and (4) investigate the relative influence of top-down, bottom-up, and climatic factors for limiting population growth rates of elk in northeast Oregon. Results from my research will help guide cougar and elk management in northeast Oregon and provide a framework for assessing relative effects of top-down, bottom-up, and abiotic factors on population growth rates of ungulates in this and other areas. I implemented a 3-year study in northeast Oregon to investigate diets, kill rates, and prey selection of cougars in a multiple-prey system to better understand mechanisms by which cougars may influence ungulate populations. During my research, 25 adult cougars were captured and fitted with Global Positioning System (GPS) collars to identify kill sites. I monitored predation sequences of these cougars for 7,642 days and located the remains of 1,213 prey items killed by cougars. Cougars killed ungulates at an average rate of 1.03 per week (95% CI = 0.92 – 1.14); however, ungulate kill rates were variable and influenced by the season and demographic classification of cougars. Cougars killed ungulates 1.55 (95% CI = 1.47 – 1.66) times more frequently during summer (May-Oct) than during winter (Nov-Apr), but killed similar amounts of ungulate biomass (8.05 kg/day; 95% CI = 6.74 – 9.35) throughout the year. Cougars killed ungulates more frequently in summer because juvenile ungulates comprised most of the diet and were smaller on average than ungulate prey killed in winter. Female cougars with kittens killed more frequently (kills/day) than males or solitary females. After accounting for the additional biomass of kittens in cougar family groups, male cougars killed on average more biomass of ungulate prey per day than did females (R = 0.41, P < 0.001), and female cougars killed more biomass of prey per day as a function of the number and age of their kittens (R = 0.60, P < 0.001). Patterns of prey selection were influenced by season and demographic classification of cougars. Female cougars selected elk calves during summer and deer fawns during winter. In contrast, male cougars selected elk calves and yearling elk during summer and elk calves during winter. My results strongly supported the hypothesis that cougar predation is influenced by season, gender, and reproductive status of the cougar and these patterns in cougar predation may be generalizable among ecosystems. The observed selection for juvenile elk and deer suggested a possible mechanism by which cougars could negatively affect population growth rates of ungulates. I investigated survival and documented causes of mortality for radio-collared cougars at 3 study areas in Oregon during 1989 – 2011. Mortality due to hunter harvest was the most common cause of death for cougars in the Catherine Creek study area and the study area combining Wenaha, Sled Springs, and Mt. Emily Wildlife Management Units (WSM study area) in northeast Oregon. In contrast, natural mortality was the most common cause of death for cougars in the Jackson Creek study area in southwest Oregon. Annual survival rates of adult males were lowest at Catherine Creek when it was legal to hunt cougars with dogs (Ŝ = 0.57), but increased following the prohibition of this hunting practice (Ŝ = 0.86). This latter survival rate was similar to those observed at Jackson Creek (Ŝ = 0.78) and WSM (Ŝ = 0.82). Regardless of whether hunting of cougars with dogs was permitted, annual survival rates of adult females were similar among study areas (Catherine Creek Ŝ = 0.86; WSM Ŝ = 0.85; Jackson Creek Ŝ = 0.85). I did not document an effect of age on cougar survival rates in the Catherine Creek study area, which I attributed to selective harvest of prime-aged, male cougars when it was legal to hunt cougars with dogs. In contrast, I observed an effect of age on annual survival in both the WSM and Jackson Creek study areas. These results indicate that sub-adult males had significantly lower survival rates than sub-adult females, but survival rates of males and females were similar by age 4 or 5 years. My results suggest that survival rates of cougars in areas where hunting cougars with dogs is illegal should be substantially higher than areas where use of dogs is legal. I used estimates of cougar vital rates from empirical data collected in northeast Oregon to parameterize a Leslie projection matrix model to estimate deterministic and stochastic population growth rates of cougars in northeast Oregon when hunting cougars with dogs was legal (1989 - 1994) and illegal (2002 - 2011). A model cougar population in northeast Oregon that was hunted with dogs increased at a mean stochastic growth rate of 21% per year (λ[subscript s] = 1.21). Similarly, I found that a model cougar population that was subjected to hunting without dogs increased at a rate of 17% per year (λ[subscript s] = 1.17). Given that hunting cougars with dogs typically results in increased harvest and reduced survival rates of cougars, it was unexpected that the cougar population subjected to hunting with dogs was increasing at a faster rate than one that was not hunted with dogs. However, cougar populations in Oregon were subjected to low harvest rates when hunting cougars with dogs was legal and harvest was male biased. This resulted in high survival rates of female cougars and correspondingly high population growth rates. The Oregon Cougar Management Plan allows the Oregon Department of Fish and Wildlife to administratively reduce cougar populations to benefit ungulate populations, reduce human-cougar conflicts, and limit livestock depredation. Consequently, I was interested in modeling the effects of a hypothetical lethal control effort on a local cougar population. Using empirically-derived vital rates and a deterministic Leslie matrix model, I found that the proportion of the cougar population that would need to be removed annually to achieve a 50% population reduction within 3 years was 28% assuming a closed population, and 48% assuming maximum immigration rates into the population. Using a stochastic Leslie matrix model, I also determined that the model cougar population would likely return to its pre-removal size in 6 years assuming a closed population, and 2 years assuming maximum immigration rates. These model results indicate that current management practices and harvest regulations, combined with short-term, intensive, and localized population reductions, are unlikely to negatively affect the short-term viability of cougar populations in northeast Oregon. However, at this time, it is not known if intensive lethal control efforts funded by state agencies will be cost-effective (i.e., increased sales of tags to hunt deer and elk will offset the costs of control efforts). Further research is needed to investigate the cost-effectiveness of cougar control efforts in Oregon. I developed a Leslie matrix population model, parameterized with empirically-derived vital rates for elk in northeast Oregon, to investigate the relative influence on elk population growth rates of (1) survival and pregnancy, and (2) top-down, bottom-up, and climatic variables. I then estimated the effect of varying the strength of top-down factors on growth rates of elk populations. Growth rates of the model elk population were most sensitive to changes in adult female survival, but due to the inherent empirical variation in juvenile survival rates explained the overwhelming majority of variation in model population growth rates (r² = 0.92). Harvest of female elk had a strong negative effect on model population growth rates of elk (r² = 0.63). An index of cougar density was inversely related to population growth rates of elk in my model (r² = 0.38). A delay in mean date of birth was associated with reduced juvenile survival, but this had a minimal effect on population growth rates in my model (r² = 0.06). Climatic variables, which were used as surrogates for nutritional condition of females, had minimal effects on population growth rates. Likewise, elk density had almost no effect on population growth rates (r² = 0.002). The results of my model provided a novel finding that cougars can be a strong limiting factor on elk populations. Wildlife managers should consider the potential top-down effects of cougars and other predators as a limiting factor on elk populations. Close