It is well documented that the incidence of renal disease, and therefore renal dysfunction, increases with age in many species of mammals. Such alterations in renal structure and function may significantly affect long-term toxicology studies. The purpose of this study was to assess the temporal evolution of glomerulosclerosis, an important renal lesion, in laboratory housed dogs, an important model system in chronic toxicological studies. We histopathologically examined representative sections of dog kidneys, quantified glomerular lesions (using the 0-5 scale of the World Health Organization classification system) and performed of statistical analysis of the extent and distribution of such changes. The kidney samples were obtained by necropsy, and occasionally biopsy, procedures from a collection of 159 purebred Beagle dogs maintained for their entire lifespan in well-controlled conditions. The lesions were correlated with sex, age, and intra-renal location of affected glomeruli to determine the relationship of each in the development of glomerulosclerosis. All dogs examined had some degree of glomerulosclerosis. In the youngest (up to 2 years of age), this was minimal, but was more advanced by middle age (3-7 years). The condition progressed with further aging and was associated with progressive fibrosis and tubular loss. Location and advancing age were significantly related to the development of glomerulosclerosis such that as age increases, the incidence of glomerulosclerosis increases, with the inner medullary ray and inner cortex demonstrating the highest occurrence. Using immunohistochemical analysis, the percentage of type IV collagen within glomeruli was determined. No significant increase in type IV collagen in glomeruli due to age or location was seen. An increase in type III or type V collagen within glomeruli was not apparent either, upon visual examination. This study indicates that renal lesions, including glomerulosclerosis, occur commonly and progress over the lifetime in a genetically similar population of laboratory Beagle dogs maintained under optimal standard environmental conditions. Such typical, age-related change needs to be taken into consideration when conducting chronic toxicological experiments using such animals. / Master of Science

No / As a highly visual and social species we communicate significantly via our physical appearance. Thus, it is unsurprising that the phenotypic aspects (including color) of our skin and hair feature prominently in such communication. Perhaps, one of the more potent reminders of aging is the change in pigmentation from birth to puberty and through to young adulthood, middle age, and beyond. Indeed, the hair bulb melanocyte may be viewed as an exquisitely sensitive aging sensor. In this context, we can appreciate that the loss of pigmentation from the hair tends to be earlier and much more striking than the age-associated pigmentation changes that we see in the epidermis. This phenotypic difference between the hair follicle and the epidermis-melanocyte subpopulations is of considerable interest, not least as both subpopulations originate from the same embyrologic neural crest and that the melanoctye stem cells in the adult hair follicle can occupy vacant niches in the epidermis. A major source of the differential aging of melanocytes in the hair bulb vs. the epidermis is likely due to the former¿s stringent coupling to the hair growth cycle when compared with the latter¿s continuous and UV-sensitive melanogenesis. Also likely to be involved is the maintenance of permissive microenvironments in these different skin compartments including their differing redox environments and variable connectivity with neuroendocrine axis. Over the last few years, we and others have striven to develop advanced cell culture methodologies for isolated hair follicle melanocytes and for intact anagen hair follicle organ culture, which may provide research tools to elucidate the regulatory mechanisms of hair follicle pigmentation. Others have assessed the robustness of the hair follicle-melanocyte stem compartment with age and other functional stressors. In the long term, it may be feasible to develop strategies to modulate some of these aging-associated changes in the hair follicle that impinge particularly of the melanocyte populations.

Peng, Cheng. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2011. / Includes bibliographical references (leaves 142-163). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.

written by Cheung Man-Chun Doris. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2000. / Includes bibliographical references (leaves 121-125). / Abstracts in English and Chinese. / ACKNOWLEDGEMENTS --- p.iii / LIST OF TABLES --- p.iv / LIST OF APPENDICES --- p.v / Chapter CHAPTER 1 --- INTRODUCTION --- p.1 / Chapter CHAPTER 2 --- BACKGROUND OF AGEING IN SELECTED COUNTRIES / Chapter A. --- "Demographic Facts: World, More Developed and Less Developed Regions" --- p.6 / Chapter B. --- "Demographic Facts: Germany, US, Japan, Singapore and Hong Kong" --- p.9 / Chapter C. --- Demographic Changes of Hong Kong --- p.12 / Chapter D. --- Fertility-dominated or Mortality-dominated ageing? --- p.14 / Chapter CHAPTER 3 --- LITERATURE REVIEW / Chapter A. --- Ageing measurements --- p.16 / Chapter B. --- Relationship between Savings and Investment --- p.17 / Chapter C. --- Relationship between Ageing and Savings --- p.19 / Chapter D. --- Relationship between Ageing and Growth --- p.23 / Chapter E. --- Relationship between Savings and Growth --- p.24 / Chapter F. --- Summary --- p.26 / Chapter CHAPTER 4 --- EMPIRICAL SPECIFICATIONS AND DATA / Chapter A. --- Expectations of variables in Savings equation andin Growth equation --- p.30 / Chapter B. --- Specifications for Panel Data Analysis / Chapter (i) --- The Data --- p.36 / Chapter (ii) --- Methodology --- p.36 / Chapter (iii) --- Specifications --- p.38 / Chapter C. --- Specifications for Cross-sectional Analysis --- p.39 / Chapter D. --- Pros and Cons of Using Panel and Cross-sectional Data --- p.40 / Chapter CHAPTER 5 --- ESTIMATATION RESULTS / Chapter A. --- Cross-sectional Data Analysis / Chapter (i) --- How does Ageing Affect Savings? --- p.45 / Chapter (ii) --- How does Ageing Affect Economic Growth? --- p.47 / Chapter B. --- Panel Data Analysis / Chapter (i) --- How does Ageing Affect Savings? --- p.48 / Chapter (ii) --- How does Ageing Affect Economic Growth? --- p.54 / Chapter C. --- Comparison between the Results from the Analyses of the Cross-sectional Data and the Panel Data --- p.56 / Chapter D. --- Reconciliation between the Conflicts --- p.57 / Chapter (i) --- Difference in the Length of Estimation Periods --- p.59 / Chapter (ii) --- Cross-sectional Effect vs. Time Series Effect --- p.60 / Chapter (iii) --- Sampling Problems --- p.66 / Chapter a) --- Results from Cutting Outliers (Full Samples) --- p.67 / Chapter b) --- Results from Cutting Outliers (Non-poor Country Samples) --- p.69 / Chapter c) --- Results from Entering both Ageing Variables Together (Full Samples) --- p.72 / Chapter d) --- Results from Entering both Ageing Variables Together (Non-poor Countries Samples) --- p.73 / Chapter E. --- Further Examination on the Impact of Ageing on the Economic Growth --- p.74 / Chapter CHAPTER 6 --- CONCLUSION --- p.78 / TABLES --- p.82 / APPENDIX --- p.113 / BIBLIOGRAPHY --- p.121

No description available.

No description available.

No description available.

Age-related declines of androgens and libido in males have been observed for decades. This dissertation sought to elucidate the mechanisms by which hormones may act differentially upon their receptors in the hypothalamus of aging compared to young males. I also examined how sexual experience modulates the ability of hormones to facilitate sexual behavior with aging. Experiment one measured androgen receptors (AR) and estrogen receptor α (ERα) cells in male rats at young, middle-aged and old age. I found that AR cell numbers in hypothalamic regions studied underwent significant age-related increases. Numbers of heavily ERα labeled cells, but not total ERα cells, increased with age. This study demonstrates that the aging brain has the capacity to synthesize hormone receptors which is increased possibly due to decreased testosterone concentrations. Experiment two examined the effect of sexual experience on serum hormones and cells of AR and ERα in hypothalamic regions in young and middle-aged males. The results showed that AR cell numbers increased with aging but did not change with experience. No age- or experience-related alteration in ERα expression occurred. However, serum testosterone increased and estradiol decreased with age. Experience increased total and free testosterone. Interactions of age and experience on total testosterone, estradiol, and luteinizing hormone were found. These results show long-lasting effects of sexual experience on hormones, but not on their receptors in the hypothalamus. Experiment three investigated effects of exogenous testosterone on sexual behavior in young and middle-aged males. The results showed a decline in sexual behavior parameters with age. After castration with testosterone treatment, there were few differences in sexual behavior measures between young and middle-aged males. AR cell numbers were higher and ERα cell numbers lower in testosterone compared to vehicle-treated males of both ages, and few effects of age occurred. These findings indicate that testosterone and aging interact in a complex manner to control numbers of cells expressing hormone receptors in the brain and on the subsequent control of sexual behavior. This insight provides a better understanding of the relationship between molecular changes in the brain and behavior, and suggests new therapeutic targets to human testosterone treatment. / text

Baby boomers are living longer, and as they age, they will need more supportive services that may include housing, mobility, nutrition, personal care, or health care. Despite the studies that have been conducted on baby boomers aging in place (choosing to stay in their home versus move to an institution), the focus has been on the old and frail and very little has been done to address the lifestyle of active (physically functioning) baby boomers. The purpose of this phenomenological study was to understand the lived, shared experiences of active baby boomers regarding their beliefs and attitudes about aging in place and the implications of this decision. The theoretical foundation of the study was based on Atchley's continuity theory. Data were gathered through in-person, semi-structured interviews with 11 participants, age 65 and older, living in a coastal area of a southern state. Data from the interviews were inductively coded and then organized around key themes. The themes from the content analysis indicated that the participants were embracing the concept of aging in place and adjusting to their limitations (i.e. physical, financial, emotional, and/or environmental) when present. Identified barriers to aging in place were access to services (specifically medical and in-home care), financial constraints, and the inability to drive or inaccessibility of transportation. This study contributes to positive social change by providing policymakers and administrators with information to strengthen the argument that the current social service delivery system is overburdened and may not meet the demands of this population in order for them to maintain their independence and autonomy. Additionally, this study raises awareness among policymakers that driving longer will in itself possess its own challenges such as visibility concerns and roadway design not conducive to aging adults.

本文係針對我國人口老化的需求與問題進行檢視，以臺北市12區戶政事務所職員及中老年人為研究對象進行研究調查，旨在了解其因個人背景變項的不同，而對人口老化所造成的需求及問題看法差異性，並探討人口老化需求與問題間的相關性，並依研究結果對政府機關作出相關政策建議。 本研究以研究者自行編製之問卷量表作為研究工具，共發出680份問卷，回收有效問卷662份，所得之資料以SPSS for Windows Version 17.0統計軟體進行敘述性統計分析及t檢定、單因子變異數分析、事後檢定法及皮爾森積差相關統計分析，以獲得實證結果。 根據分析結果，研究發現如下： 一、在人口老化衍生問題各構面間，以照護資源問題得分最高。 二、在人口老化衍生需求各構面間，以生活規劃需求得分最高。 三、在個人背景變項中，對照護資源、環境及心理適應等問題有顯著差異。 四、在個人背景變項中，大部分對就業與長照保障及生活規劃等需求有顯著差異。 五、而在人口老化衍生問題與需求間有著顯著正相關。 / The present paper focuses on examining the demand and problem of population aging in Taiwan, conducting a research survey on employees of the 12 district household registration offices and middle-aged and elder persons in Taipei, with the intention of understanding the differences in views regarding demand and problem caused by population aging as a result of variations in personal background variables. In addition, the present paper also probes the relationship between demand and problem of population aging, making related policy suggestions to government authorities based on the results of the study. In the study, researchers used a questionnaire that they had compiled as the research tool, distributing 680 copies of the questionnaire in total and recovering 662 valid copies of the questionnaire. Using the SPSS for Windows Version 17.0 software, descriptive statistics, t-test, one-way ANOVA, post hoc tests, and Pearson’s product-moment correlation were carried out to analyze the data obtained in order to acquire empirical results. According to results of analyses, the findings were as follows: 1. Among the various dimensions of problem derived from population aging, the score for the care resources problem was the highest. 2. Among the various dimensions of demand derived from population aging, the score for the life planning need was the highest. 3. Among the personal background variables, significant differences were shown in problem like care resources, environment, and mental adjustment. 4. Among the personal background variables, the majority of them showed significant differences in demand like employment, long-term protection, and life planning. 5. Problem and demand derived from population aging demonstrated a significant positive relationship.