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Aging, diversity, and health: the Brazilian and the Canadian context
Paskulin, Lisiane Manganelli Girardi;Aires, Marinês;Goncalves, Ana Valéria;Kottwitz, Carla Cristiane Becker;Morais, Eliane Pinheiro de;Brondani, Mario Augusto;
Acta Paulista de Enfermagem , 2011, DOI: 10.1590/S0103-21002011000600021
Abstract: aging is a universal and yet diverse phenomenon. this paper presents a review on the topic of diversity in the context of the aging populations in brazil and canada. the diversity of the aging population in both countries is discussed in terms of gender, ethnicity, age groups and living conditions while considering the impact on the health care systems. understanding and reflecting on the brazilian and canadian realities reinforces the need for respecting these diversities when developing and implementing local health policies and interventions. there are some similarities regarding gender, but marked differences in immigration patterns, education and living arrangements. the heterogeneity in the aging process within each country and between them carries different expectations and generates social consequences that manifest themselves in differences in health situations, resulting in new challenges to health services and the formulation of public policies for this age group in both countries.
Change and Aging Senescence as an Adaptation  [PDF]
André C. R. Martins
PLOS ONE , 2011, DOI: 10.1371/journal.pone.0024328
Abstract: Understanding why we age is a long-lived open problem in evolutionary biology. Aging is prejudicial to the individual, and evolutionary forces should prevent it, but many species show signs of senescence as individuals age. Here, I will propose a model for aging based on assumptions that are compatible with evolutionary theory: i) competition is between individuals; ii) there is some degree of locality, so quite often competition will be between parents and their progeny; iii) optimal conditions are not stationary, and mutation helps each species to keep competitive. When conditions change, a senescent species can drive immortal competitors to extinction. This counter-intuitive result arises from the pruning caused by the death of elder individuals. When there is change and mutation, each generation is slightly better adapted to the new conditions, but some older individuals survive by chance. Senescence can eliminate those from the genetic pool. Even though individual selection forces can sometimes win over group selection ones, it is not exactly the individual that is selected but its lineage. While senescence damages the individuals and has an evolutionary cost, it has a benefit of its own. It allows each lineage to adapt faster to changing conditions. We age because the world changes.
Diagnose This Quiz
Community Eye Health Journal , 2012,
Abstract: Picture quiz - what is the most likely diagnosis?
Canadian provincial, territorial, and federal government aging policies: A systematic review  [PDF]
Donna Marie Wilson, Jane Osei-Waree, Jessica Anne Hewitt, Andrew Broad
Advances in Aging Research (AAR) , 2012, DOI: 10.4236/aar.2012.12005
Abstract: In most countries, population aging is becoming more evident now that the first members of the large babyboom cohort have reached 65 years of age. As an accelerating increase in the number of older persons and the proportion of the public aged 65 and older will now occur, planning for population aging has become ever more crucially important. A systematic review of Canadian provincial, territorial, and federal government documents was undertaken to search for the existence of population aging policies, and to determine the aims and other content of the most current policy documents. Documents were identified in all but two jurisdictions of Canada (two northern territories). Document developers, and the aims and content of the 14 reviewed documents varied considerably. Some similarities were identified, however, including some common stated purposes for these documents - to address current issues and challenges facing older people and to plan ahead for a preferred future with population aging.
The aging Canadian population and hospitalizations for acute myocardial infarction: projection to 2020
Nigel SB Rawson, Rong Chu, Afisi S Ismaila, Jorge Terres
BMC Cardiovascular Disorders , 2012, DOI: 10.1186/1471-2261-12-25
Abstract: Aggregated data on annual AMI hospitalizations were obtained from the Canadian Institute for Health Information for all provinces and territories, except Quebec, for 2002/03 and 2009/10. Using these data in a Poisson regression model to control for age, gender and year, the rate of AMI hospitalizations was extrapolated between 2010 and 2020. The extrapolated rate and Statistics Canada population projections were used to estimate the number of AMI hospitalizations in 2020.The rates of AMI hospitalizations by gender and age group showed a decrease between 2002 and 2009 in patients aged ≥ 65 years and relatively stable rates in those aged < 64 years in both males and females. However, the total number of AMI hospitalizations in Canada (excluding Quebec) is projected to increase by 4667 from 51847 in 2009 to 56514 in 2020, a 9.0% increase. Inflating this number to account for the unavailable Quebec data results in an increase of approximately 6200 for the whole of Canada. This would amount to an additional cost of between $46 and $54 million and sensitivity analyses indicate that it could be between $36 and $65 million.Despite projected decreasing or stable rates of AMI hospitalization, the number of hospitalizations is expected to increase substantially as a result of the aging of the Canadian population. The cost of these hospitalizations will be substantial. An increase of this extent in the number of AMI hospitalizations and the ensuing costs would significantly impact the already over-stretched Canadian healthcare system.Despite therapeutic advances in the treatment of acute myocardial infarction (AMI) over the past two decades, the condition continues to be a leading cause of death in older adults in developed countries. Since the risk of experiencing an AMI increases with age [1], changes in the occurrence of this disorder have a major impact on the overall health of a country's population and its healthcare system.In Canada, the population is aging and the count
Aging and the Necessity of a Radical Reform of the Canadian Pension System  [PDF]
Henripin, Jacques
Canadian Studies in Population , 2009,
Abstract: Compared to the 29 other members of OECD, Canadian workers must satisfy themselves with a rather timorous public pension system, particularly those who earn a middle or higher income.This weakness is somewhat corrected by private pension organizations, but only a third of employees are covered by them. The author proposes that all workers have access to such programs and even that they are mandatory. There would be many of them; they would functionon the basis of capitalization; they would be public or private. The choice of the capitalization financial principle is almost essential, due to future population aging. The author displays his convictions about these proposals, as well as practical ways to implement such a program. Résumé Par rapport à ceux des 29 autres pays de l’OCDE, les travailleurs canadiens doivent se satisfaire d’un système de pensions publiques plut t timoré, particulièrement ceux qui gagnent un revenu moyen ou élevé. Cette faiblesse est corrigée, peut-on dire, par des systèmes de pensions privées, mais seulement le tiers des employés en bénéficient. L’auteur propose que tous les travailleurs aient accès à de tels programmes et même qu’ils soient obligatoires. Il y en auraitplusieurs ; ils seraient gérés suivant le principe de capitalisation ; ils seraient publics ou privés. Le choix du principe de capitalisation est presque essentiel, à cause du vieillissementfutur de la population. L’auteur expose ses convictions là-dessus, de même que des moyens pratiques de réaliser un tel programme.
Mechanical aging and non-linear rheology of concentrated colloidal suspensions: experimental facts and simple models  [PDF]
Armand Ajdari
Physics , 2003,
Abstract: Many colloidal systems display very non-Newtonian and solid-like behaviour when concentrated, a striking feature being the apparition of a yield stress. After recalling some basics about the interactions between colloidal particles, I present a few experimental facts commonly observed in these systems: aging and non-linear rheology. A simple phenomenological model is then introduced, in which the local state of the system is described by a single scalar parameter, the fluidity. I proceed with comments on heterogeneous flows in some of these systems. These notes are not intended to be a comprehensive review, and the reader is directed to the references for further reading
Yeast Colonies: A Model for Studies of Aging, Environmental Adaptation, and Longevity  [PDF]
Libu?e Váchová,Michal ?áp,Zdena Palková
Oxidative Medicine and Cellular Longevity , 2012, DOI: 10.1155/2012/601836
Abstract: When growing on solid surfaces, yeast, like other microorganisms, develops organized multicellular populations (colonies and biofilms) that are composed of differentiated cells with specialized functions. Life within these populations is a prevalent form of microbial existence in natural settings that provides the cells with capabilities to effectively defend against environmental attacks as well as efficiently adapt and survive long periods of starvation and other stresses. Under such circumstances, the fate of an individual yeast cell is subordinated to the profit of the whole population. In the past decade, yeast colonies, with their complicated structure and high complexity that are also developed under laboratory conditions, have become an excellent model for studies of various basic cellular processes such as cell interaction, signaling, and differentiation. In this paper, we summarize current knowledge on the processes related to chronological aging, adaptation, and longevity of a colony cell population and of its differentiated cell constituents. These processes contribute to the colony ability to survive long periods of starvation and mostly differ from the survival strategies of individual yeast cells. 1. Introduction The molecular basis of aging has been examined using numerous methods and organisms and is one of the main biological questions under investigation. A substantial amount of information on individual gene products, metabolic pathways, signal transduction cascades, environmental factors, and cellular mechanisms impacting aging is available, but a deeper insight into how all these components interact under specific conditions and how they contribute to the process of aging is still unavailable. In addition, aging is tightly linked with the process of adaptation, through which the cells adjust to a hostile environment and can reenter the proliferative state. With metazoans, this potentially leads to tumor formation and the subsequent death of the organism. Yeast cells have been used for a long time as a tool for identifying the genes and pathways involved in basic cellular processes such as the cell cycle, aging, and stress response. Two types of lifespan, the replicative and the chronological, have been defined and studied in the yeast Saccharomyces cerevisiae [1]. While the replicative (mitotic) lifespan is characterized by the number of divisions that an individual yeast cell can undergo, the chronological (postmitotic) lifespan represents a period during which nondividing (stationary phase, G0) yeast cells remain viable. Various
Yeast Colonies: A Model for Studies of Aging, Environmental Adaptation, and Longevity  [PDF]
Libu e Váchová,Michal áp,Zdena Palková
Oxidative Medicine and Cellular Longevity , 2012, DOI: 10.1155/2012/601836
Abstract: When growing on solid surfaces, yeast, like other microorganisms, develops organized multicellular populations (colonies and biofilms) that are composed of differentiated cells with specialized functions. Life within these populations is a prevalent form of microbial existence in natural settings that provides the cells with capabilities to effectively defend against environmental attacks as well as efficiently adapt and survive long periods of starvation and other stresses. Under such circumstances, the fate of an individual yeast cell is subordinated to the profit of the whole population. In the past decade, yeast colonies, with their complicated structure and high complexity that are also developed under laboratory conditions, have become an excellent model for studies of various basic cellular processes such as cell interaction, signaling, and differentiation. In this paper, we summarize current knowledge on the processes related to chronological aging, adaptation, and longevity of a colony cell population and of its differentiated cell constituents. These processes contribute to the colony ability to survive long periods of starvation and mostly differ from the survival strategies of individual yeast cells.
Misrepair accumulation theory: a theory for understanding aging, cancer development, longevity, and adaptation  [PDF]
Jicun Wang-Michelitsch,Thomas M. Michelitsch
Quantitative Biology , 2015,
Abstract: Misrepair accumulation theory is a novel theory in interpreting aging phenomena. With a new concept of Misrepair, this theory reaches a unified understanding of aging: aging of an organism is a result of accumulation of Misrepairs of its structure. Misrepair accumulation theory (MA theory) is distinct and it can improve our understanding of life on several aspects. I. MA theory is fundamentally different from other theories by: A. proposing a generalized concept of Misrepair; B. pointing out the evolutionary advantage of aging mechanism; and C. distinguishing between aging of a cell and aging of a tissue. II. MA theory overcomes the limitations of traditional theories on interpreting the phenomena of tissue fibrosis and cancer development. Tissue fibrosis, as a result of accumulation of Misrepairs with collagen fibers, is a powerful evidence for demonstrating the central role of Misrepairs in aging. Cancer development is a result of accumulation of DNA Misrepairs in somatic cells, which needs to proceed over many generations of cells in a regenerable tissue. III. MA theory improves also our understanding on longevity, premature aging, adaptation, and species evolution. The potential of longevity of an organism is hidden in the complexity of its structure.
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