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Consequences for the Bovine Embryo of Being Derived from a Spermatozoon Subjected to Post-Ejaculatory Aging and Heat Shock: Development to the Blastocyst Stage and Sex Ratio

HENDRICKS, Katherine Elizabeth May; MARTINS, Leydson; HANSEN, Peter James
Fonte: JAPANESE SOC ANIMAL REPRODUCTION Publicador: JAPANESE SOC ANIMAL REPRODUCTION
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
36.57%
The objective was to determine whether aging of sperm caused by incubation at normothermic (38.5 C) or heat shock (40 C) temperatures for 4 h prior to oocyte insemination affects sperm motility, fertilizing ability, competence of the resultant embryo to develop to the blastocyst stage and blastocyst sex ratio. In the first experiment, the percent of sperm that were motile was reduced by aging (P<0.001) and the reduction in motility was greater for sperm at 40 C compared to sperm at 38.5 C (P<0.01). In the second experiment, oocytes were inseminated with aged sperm. A smaller percent of oocytes fertilized with sperm aged at either temperature cleaved by Day 3 after insemination than oocytes fertilized with fresh sperm (P<0.05). There was no effect of sperm aging on the percent of oocytes or cleaved embryos that developed to the blastocyst stage. Aging of sperm before fertilization at 38.5 C reduced the percent of blastocysts that were male (P=0.08). In the third experiment, incubation of sperm at 38.5 C or 40 C for 4 h did not reduce fertilizing ability of sperm as determined by pronuclear formation at 18 h post insemination. In conclusion, aging of sperm reduced cleavage rate and the percent of blastocysts that were males but had no effect on the developmental capacity of the. embryo. The effect of aging on cleavage rate may represent reduced motility and errors occurring after fertilization and pronuclear formation. Aging at a temperature characteristic of maternal hyperthermia had little additional effect except that polyspermy was reduced. Results indicate that embryo competence for development to the blastocyst stage is independent of sperm damage as a result of aging for 4 h at normothermic or hyperthermic temperatures.; National Research Initiative Competitive[2007-35203-18070]; U.S. Department of Agriculture Cooperative State Research...

Influence of Artificial Accelerated Aging on Dimensional Stability of Acrylic Resins Submitted to Different Storage Protocols

GARCIA, Lucas da Fonseca Roberti; ROSELINO, Lourenco de Moraes Rego; MUNDIM, Fabricio Mariano; PIRES-DE-SOUZA, Fernanda de Carvalho Panzeri; CONSANI, Simonides
Fonte: WILEY-BLACKWELL Publicador: WILEY-BLACKWELL
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
36.61%
Purpose: The aim of this study was to evaluate the influence of artificial accelerated aging on dimensional stability of two types of acrylic resins (thermally and chemically activated) submitted to different protocols of storage. Materials and Methods: One hundred specimens were made using a Teflon matrix (1.5cmx0.5mm) with four imprint marks, following the lost-wax casting method. The specimens were divided into ten groups, according to the type of acrylic resin, aging procedure, and storage protocol (30 days). GI: acrylic resins thermally activated, aging, storage in artificial saliva for 16 hours, distilled water for 8 hours; GII: thermal, aging, artificial saliva for 16 hours, dry for 8 hours; GIII: thermal, no aging, artificial saliva for 16 hours, distilled water for 8 hours, GIV: thermal, no aging, artificial saliva for 16 hours, dry for 8 hours; GV: acrylic resins chemically activated, aging, artificial saliva for 16 hours, distilled water for 8 hours; GVI: chemical, aging, artificial saliva for 16 hours, dry for 8 hours; GVII: chemical, no aging, artificial saliva for 16 hours, distilled water for 8 hours; GVIII: chemical, no aging, artificial saliva for 16 hours, dry for 8 hours GIX: thermal, dry for 24 hours; and GX: chemical...

Efeito do protocolo de ativação da polimerização e envelhecimento acelerado em algumas propriedades de cimentos resinosos; Effects of polymerization activation protocol and accelerated aging in some resin cements properties

Pegoraro, Thiago Amadei
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 26/02/2010 PT
Relevância na Pesquisa
36.62%
Este estudo teve como objetivo avaliar os efeitos de variações no protocolo de ativação e envelhecimento acelerado em algumas propriedades de cimentos resinosos de polimerização dual. Adicionalmente, investigaram-se os efeitos da variação da temperatura ambiente e envelhecimento acelerado no tempo de trabalho e tempo de presa dos cimentos quando ativados exclusivamente pela reação química. As propriedades avaliadas foram o grau de conversão, determinado por espectrometria no infravermelho com transformada de Fourier (FTIR-ATR), microdureza Knoop, expressa em KHN, e resistência mecânica à tração expressa em MPa. Os tempos de trabalho e tempos de presa foram determinados por um reômetro oscilatório com controle de temperatura da plataforma de teste estabelecida em 24oC ou 37oC. O envelhecimento acelerado foi determinado pela armazenagem dos cimentos, em suas embalagens originais, e após os testes iniciais, em estufa a 37oC por 12 semanas.A variável de modo de ativação foi determinada em 3 níveis. Os cimentos foram manipulados de acordo com as instruções dos fabricantes e ativados por luz imediatamente (controle), ativados por luz após 10 minutos de reação química no escuro (Exp 1) ou mantidos no escuro por 15 minutos...

Correlação estrutura-propriedades de silicones para prótese facial - Efeitos da pigmentação e do envelhecimento; Correlation structure-properties of silicones for facial prosthesis - Effects of pigmentation and aging

Pinheiro, Juliana Barchelli
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 13/04/2012 PT
Relevância na Pesquisa
36.59%
Este estudo avaliou a dureza Shore A, alteração de cor, recuperação elástica e resistência ao rasgamento de um silicone experimental (Ortho Pauher - O), quando comparado a um silicone usado em reabilitações faciais (MDX 4-4210 - MDX), quando submetidos à pigmentação e envelhecimento e ainda, analisou a micro estrutura desses materiais. Para análise da alteração de cor e dureza foram obtidos 160 espécimes circulares (80/material); para os ensaios de recuperação elástica foram obtidos 200 espécimes cilíndricos (100/material) e para o ensaio de resistência ao rasgamento, foram confeccionados 200 espécimes em forma de calça (100/material). Metade dos espécimes recebeu pigmentação intrínseca e a outra metade, pigmentação intrínseca e extrínseca, por meio da adição de pó de maquiagem. Em seguida, foram distribuídos aleatoriamente em três grupos de envelhecimento: 1 termociclagem (T), 2 - luz ultravioleta (UV) e 3 - luz natural (LN). O envelhecimento simulou um período de uso de um ano. Como controle (C), os espécimes foram mantidos em um recipiente fechado e na ausência total de luz por um ano. Para as análises micro estruturais, três espécimes de cada grupo foram submetidos à Microscopia Eletrônica de Varredura (MEV)...

Avaliação dos produtos finais de glicosilação e o fator nuclear K-B em glandulas lacrimais e superficie ocular de modelos animais de diabetes e envelhecimento; Advanced glycation end-products and Nuclear Factor K-B in lacrimal glands and ocular surface of diabetes and aging animal models

Monica de Cassia Alves
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 21/07/2006 PT
Relevância na Pesquisa
36.59%
Este estudo avaliou as possíveis vias comuns na fisiopatogênese da síndrome do olho seco no Diabetes Mellitus (DM) e no envelhecimento, envolvendo o acúmulo dos produtos de glicosilação ("Advanced Glycation End-products" - AGEs), seu receptor RAGE e a ativação do Fator Nuclear-?B (NF-?B) na glândula lacrimal (GL) e alterações do filme lacrimal nessas condições. Modelos animais de DM induzido com estreptozotocina e animais senis (24 meses de vida) foram comparados a animais controle tratados com tampão citrato e adultos jovens (2 meses de vida). Foram avaliadas vias de sinalização, envolvendo AGEs, RAGE e a ativação do NF-?B na GL e alterações no filme lacrimal em ratos Wistar de todos os grupos. A análise do filme lacrimal foi realizada através de medidas de volume de secreção basal e dosagem de citocinas como a Interleucina-1 ß (IL-1 ß) e Fator de Necrose Tumoral - a (TNF- a). A capacidade secretória da GL foi avaliada através de medidas da atividade de peroxidase. Técnicas de "western blot" foram utilizadas para avaliar a expressão e ativação do NF-?B na GL. A expressão de AGE, RAGE e NF-?B na GL e córnea nos grupos estudados, foi avaliada através de microscopia confocal com imunofluorescência. O volume lacrimal foi significativamente menor nos animais diabéticos e senis (P=0...

Avaliação global de transcritos associados ao envelhecimento da epiderme humana utilizando microarranjos de DNA = : Global evaluation of transcripts associated to human epidermal aging with DNA microarrays; Global evaluation of transcripts associated to human epidermal aging with DNA microarrays

Márcio Lorencini
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 31/01/2014 PT
Relevância na Pesquisa
36.6%
Com o aumento do tempo de vida da população humana muitas modalidades médicas, incluindo a dermatologia, deparam-se com uma revolução na forma de garantir saúde e qualidade de vida aos pacientes. Em contato com o ambiente externo, a pele representa um órgão no qual as mudanças com o envelhecimento causam danos funcionais, além de potencial impacto estético e psicossocial. A epiderme, camada mais externa da pele, constitui uma barreira seletiva com destacada capacidade de renovação e manutenção da homeostasia corporal. Entretanto, o entendimento de diversos mecanismos associados à fisiologia e envelhecimento da epiderme permanece como desafio para a comunidade científica. Com base nesse cenário, o objetivo do presente trabalho foi compreender o atual estado da arte no tema de envelhecimento da epiderme e realizar experimentos voltados para lacunas existentes, com foco na integração de aspectos clínicos, fisiológicos, morfológicos, celulares e moleculares. O capítulo de abertura descreve uma avaliação global de transcritos associados ao envelhecimento da epiderme humana, com a técnica de microarranjos de DNA e coleta não invasiva com fitas adesivas. O estudo indica características moleculares específicas do fotoenvelhecimento epidermal...

Influence of Artificial Accelerated Aging on Dimensional Stability of Acrylic Resins Submitted to Different Storage Protocols

GARCIA, Lucas da Fonseca Roberti; ROSELINO, Lourenco de Moraes Rego; MUNDIM, Fabricio Mariano; PIRES-DE-SOUZA, Fernanda de Carvalho Panzeri; CONSANI, Simonides
Fonte: WILEY-BLACKWELL Publicador: WILEY-BLACKWELL
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
36.61%
Purpose: The aim of this study was to evaluate the influence of artificial accelerated aging on dimensional stability of two types of acrylic resins (thermally and chemically activated) submitted to different protocols of storage. Materials and Methods: One hundred specimens were made using a Teflon matrix (1.5cmx0.5mm) with four imprint marks, following the lost-wax casting method. The specimens were divided into ten groups, according to the type of acrylic resin, aging procedure, and storage protocol (30 days). GI: acrylic resins thermally activated, aging, storage in artificial saliva for 16 hours, distilled water for 8 hours; GII: thermal, aging, artificial saliva for 16 hours, dry for 8 hours; GIII: thermal, no aging, artificial saliva for 16 hours, distilled water for 8 hours, GIV: thermal, no aging, artificial saliva for 16 hours, dry for 8 hours; GV: acrylic resins chemically activated, aging, artificial saliva for 16 hours, distilled water for 8 hours; GVI: chemical, aging, artificial saliva for 16 hours, dry for 8 hours; GVII: chemical, no aging, artificial saliva for 16 hours, distilled water for 8 hours; GVIII: chemical, no aging, artificial saliva for 16 hours, dry for 8 hours GIX: thermal, dry for 24 hours; and GX: chemical...

Cats, “Rats,” and Bats: The Comparative Biology of Aging in the 21st Century

Austad, Steven N.
Fonte: Oxford University Press Publicador: Oxford University Press
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
36.59%
Laboratory models have suggested a link between metabolism and life span in vertebrates, and it is well known that the evolution of specific life histories can be driven by metabolic factors. However, little is known regarding how the adoption of specific life-history strategies can shape aging and life span in populations facing different energetic demands from either a theoretical or a mechanistic viewpoint but significant insight can be gained by using a comparative approach. Comparative biology plays several roles in our understanding of the virtually ubiquitous phenomenon of aging in animals. First, it provides a critical evaluation of broad hypotheses concerning the evolutionary forces underlying the modulation of aging rate. Second, it suggests mechanistic hypotheses about processes of aging. Third, it illuminates particularly informative species because of their exceptionally slow or rapid aging rates to be interrogated about potentially novel mechanisms of aging. Although comparative biology has played a significant role in research on aging for more than a century, the new comparative biology of aging is poised to dwarf those earlier contributions, because: (1) new cellular and molecular techniques for investigating novel species are in place and more are being continually generated...

Evidence that mutation accumulation does not cause aging in Saccharomyces cerevisiae

Kaya, Alaattin; Lobanov, Alexei V; Gladyshev, Vadim N
Fonte: BlackWell Publishing Ltd Publicador: BlackWell Publishing Ltd
Tipo: Artigo de Revista Científica
EN_US
Relevância na Pesquisa
36.59%
The concept that mutations cause aging phenotypes could not be directly tested previously due to inability to identify age-related mutations in somatic cells and determine their impact on organismal aging. Here, we subjected Saccharomyces cerevisiae to multiple rounds of replicative aging and assessed de novo mutations in daughters of mothers of different age. Mutations did increase with age, but their low numbers, < 1 per lifespan, excluded their causal role in aging. Structural genome changes also had no role. A mutant lacking thiol peroxidases had the mutation rate well above that of wild-type cells, but this did not correspond to the aging pattern, as old wild-type cells with few or no mutations were dying, whereas young mutant cells with many more mutations continued dividing. In addition, wild-type cells lost mitochondrial DNA during aging, whereas shorter-lived mutant cells preserved it, excluding a causal role of mitochondrial mutations in aging. Thus, DNA mutations do not cause aging in yeast. These findings may apply to other damage types, suggesting a causal role of cumulative damage, as opposed to individual damage types, in organismal aging.

Influência da terapia endodôntica e do envelhecimento artificial acelerado na resistência de união de pinos de fibra de vidro à dentina intrarradicular; Influence of endodontic therapy and artificial accelerated aging on fibreglass post bond strength to intraradicular dentine

Santana, Fernanda Ribeiro
Fonte: Universidade Federal de Goiás; Brasil; UFG; Programa de Pós-graduação em Ciências da Saúde (FM); Faculdade de Medicina - FM (RG) Publicador: Universidade Federal de Goiás; Brasil; UFG; Programa de Pós-graduação em Ciências da Saúde (FM); Faculdade de Medicina - FM (RG)
Tipo: Tese de Doutorado Formato: application/pdf
POR
Relevância na Pesquisa
36.57%
Aim: To evaluate in vitro the influence of root canal instrumentation techniques, endodontic irrigants, endodontic sealers and artificial accelerated aging on fibreglass post bond strength to bovine intraradicular dentine. Methodology: Part 1. 120 bovine incisors were divided into 12 experimental groups (n=10) resulting from the interaction among 3 study factors: root canal instrumentation technique (RCPSS- root canal preparation with stainless steel instruments - KFile; RCPNiTi- root canal preparation with K3 Nickel-Titanium instruments), endodontic irrigant (NaOCl- 1% sodium hypochlorite; CHX- 2% chlorhexidine; O3- 1.2% ozonated water) (in all samples 17% EDTA was used to remove the smear layer) and specimens artificial accelerated aging (Immediate, test with no aging; Mediate, test performed after 2 months of water storage at 37°C). After root canal preparation, endodontic filling was not performed. Fibreglass posts were cemented with self-adhesive resin cement (RelyX U100, 3M-ESPE) and roots were cross-sectioned to obtain two slices of each third. Samples were submitted to micropush-out test and bond strength values (MPa) were analyzed by ANOVA in a split-plot arrangement and Tukey’s test (α = 0.05). Failure modes were evaluated under a confocal microscope. Part 2. 60 bovine incisors were divided into 6 experimental groups (n=10) resulting from the interaction between 2 study factors: endodontic sealer (Sx- Sealapex; S26- Sealer 26; AHAH Plus) and specimens artificial accelerated aging (Immediate...

Aging policy: a case study of co-ordination in Canadian governments

Kuper, Olivia B.
Fonte: Brock University Publicador: Brock University
Tipo: Electronic Thesis or Dissertation
ENG
Relevância na Pesquisa
36.57%
ABSTRACT Canada is an aging society. The number of people aged sixty-five and over is rising, while the number of people under twenty is declining. These two concurrent changes in the age structure have produced a sh~ft in the demographic composition of Canada which is commonly referred to as the aging phenomenon. Regardless of whether or not the number of people under twenty continues to decline, the number of elderly in Canada will almost double over the next twenty years. This rapidly growing elderly clientele will doubtless have an impact on Canadian governments. Federal, provincial and municipal governments are presently providing a variety of programs that have a special bearing on the aged and most senior citizens are beneficiaries of one or more of these programs. The ramifications of a rapidly growing elderly clientele are obvious. In order to cope with the impact of a significant increase in the number of elderly persons, the development and implementation of aging policy must be co-ordinated at each level of government and between and among levels of government. If aging policy is not co-ordinated, the results are likely to be: inappropriate policy decisions; duplication and overlap; and, ineffective and irresponsive services. No one benefits from these results. The need for co-ordination is apparent. The purpose of this thesis is to examine existing governmental efforts to co-ordinate policy in the field of aging. These efforts are examined by focusing on interactions directed at co-ordination between and among major actors in aging policy. A framework is used to structure the description and analysis of these interactions. The variables of formalisation and intensity and the concept of power are instrumental in analysing interactions for co-ordination. The underlying intent of this thesis is to discover some of the main gaps in existing governmental efforts to co~ordinate aging policy. Gaps are...

Some Economic Consequences of Global Aging : A Discussion Note for the World Bank

Lee, Ronald; Mason, Andrew; Cotlear, Daniel
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
EN_US
Relevância na Pesquisa
36.59%
The note describes the importance of population aging world-wide, clarifying its prevalence among middle- and low-income countries, which suggests that many developing countries are getting old before they are growing rich. The note then asks in what way population aging is an economic problem and what are the specific challenges facing developing countries in this process. The note argues against the common, time-bomb perception?, and clarifies how a simplistic extrapolation from the impact of aging on single programs such as public pensions gives a misleading impression about the more general macroeconomic consequences of population aging, where numerous elements contribute to a more nuanced result. The note briefly discusses various topics of importance in the population aging debate, including: intergenerational flows, social contracts, the risk management element of old-age policies, and the impact of aging on health care costs. The note seeks to share a number of counterintuitive or simply non-intuitive facts...

Fiscal Policy Issues in the Aging Societies

Bogetic, Zeljko; Onder, Harun; Onal, Anil; Skrok, Emilia; Schwartz, Anita; Winkler, Hernan
Fonte: Banco Mundial Publicador: Banco Mundial
Tipo: Trabalho em Andamento
EN_US
Relevância na Pesquisa
36.62%
Aging may be one of the most far-reaching processes defining the economic, fiscal, and social changes societies are likely to experience over the next 40 years. The demographic consequences of aging will have a dramatic impact on labor markets, economic growth, social structures--and government budgets. These issues have gained urgency after the second largest global recession in the past 100 years. Based on a broad comparative analysis of countries that include the EU and non-EU European and Central Asian countries, as well as several case studies and model simulations, the paper seeks to provide broad answers--tailored in part to distinct groups of countries according to their aging-fiscal profiles--to major questions facing governments budgets in aging societies: What are the fiscal-aging profiles of Western European, emerging European, and Central Asian countries? In other words, how good or bad is their fiscal situation--"initial conditions"--in view of their emerging aging-related problems? What kind of public spending pressures are likely to emerge in the coming decades...

Aging of cerebellar granule neurons in vitro; Alterungsprozess von cerebellaren Körner-Neuronen in vitro

Pekanovic, Ana
Fonte: Universidade de Tubinga Publicador: Universidade de Tubinga
Tipo: Dissertação
EN
Relevância na Pesquisa
36.57%
Aging is slow and cumulative process and is experimentally difficult to access. Neurodegenerative diseases such as Alzheimer’s disease and Parkinson’s disease are considered to be at high risk with increasing age. The molecular mechanisms by which they occur are not completely understood. Aim of the present study was to construct and investigate an in vitro model of neuronal aging. To this purpose we used rat primary cerebellar granule neurons which are a good characterized in vitro model for various paradigms of neuronal cell death, e.g. potassium deprivation or glutamate excitotoxicity. We prepared CGN to a purity of 95% and kept them in culture for either 7 days or up to 60 days. To validate our in vitro model for aging, we tested whether known molecular changes associated with aging occur over time. Moreover, by using DNA microarray analysis we examined how aging in vitro influences the pattern of gene expression. In the end, we studied mechanisms of cell death signaling cascades in young vs. old CGN. Old CGN had increased protein carbonylation and ubiquitination. Proteasomal activity was significantly lower in old CGN even though protein expression of proteasomal subunits did not change over the time. Morphological changes in astrocytes included increase in size...

Aging of NAPLs interfaces in porous media and their effects on mass transfer of organic contaminants; Alterungsprozesse von NAPL-Oberflächen in porösen Medien und ihr Einfluß auf den Massentransfer von organischen Schadstoffen

Lihua Liu
Fonte: Universität Tübingen Publicador: Universität Tübingen
Tipo: Dissertação
EN
Relevância na Pesquisa
36.61%
Groundwater and soil contaminated by organic compounds is a world wide environmental problem. Coal tar, crude oil and other complex multicomponent mixtures introduced into the subsurface by accident, uncontrolled discharging and unsuitable treatment of the products and byproducts, were persistent and act as continuous sources of contaminants. These complex mixtures are liquid, immiscible with water and known as non-aqueous phase liquids (NAPLs). The compounds inside the bulk NAPLs phase may move into gas, water and solid phase in the subsurface environment. This transferring process includes evaporation, volatilization, dissolution, diffusion, sorption and chemical and biochemical reaction. The NAPLs interfacial phase may be subject to a visible phase change during this process, that is the bulk liquid phase may change to a viscous or solid phase. This process of phase change is referred to as “aging”, and the newly formed visible interfacial phase is named as “aged film” or “skin film”. This aging process may change the mechanical, physical and chemical properties of the interfacial phase. Subsequently, affect the mass transfer, spreading, recovery and bioavailablity of NAPL and solutes in NAPL. The aging phenomenon of NAPLs was studied in this work by pendant drop test and batch experiment...

Anti-aging therapy through fitness enhancement

Castillo Garz??n, Manuel J.; Ruiz, Jonatan R.; Ortega Porcel, Francisco B.; Guti??rrez, ??ngel
Fonte: Dove Medical Press; Society for Applied Research in Aging (SARA) Publicador: Dove Medical Press; Society for Applied Research in Aging (SARA)
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
46.42%
Physical exercise is proposed as a highly effective means of treating and preventing the main causes of morbidity and mortality ??? most of which are associated with aging ??? in industrialized countries. Low physical fitness is an important risk factor for cardiovascular and all-causes morbidity and mortality; indeed, it is even a predictor of these problems. When properly measured, the assessment of physical fitness can be a highly valuable indicator of health and life expectancy and, therefore, should be performed routinely in the clinical setting. Individually adapted training programs could be prescribed based on fitness assessment results and an adequate knowledge of patient lifestyle and daily physical activity. Such training programs would allow people to develop their maximum physical potential, improve their physical and mental health, and attenuate the negative consequences of aging.

Expansion of the calcium hypothesis of brain aging and Alzheimer's disease: minding the store

Thibault, Olivier; Gant, John C; Landfield, Philip W
Fonte: Blackwell Publishing Ltd Publicador: Blackwell Publishing Ltd
Tipo: Artigo de Revista Científica
Publicado em /06/2007 EN
Relevância na Pesquisa
36.59%
Evidence accumulated over more than two decades has implicated Ca2+ dysregulation in brain aging and Alzheimer's disease (AD), giving rise to the Ca2+ hypothesis of brain aging and dementia. Electrophysiological, imaging, and behavioral studies in hippocampal or cortical neurons of rodents and rabbits have revealed aging-related increases in the slow afterhyperpolarization, Ca2+ spikes and currents, Ca2+ transients, and L-type voltage-gated Ca2+ channel (L-VGCC) activity. Several of these changes have been associated with age-related deficits in learning or memory. Consequently, one version of the Ca2+ hypothesis has been that increased L-VGCC activity drives many of the other Ca2+-related biomarkers of hippocampal aging. In addition, other studies have reported aging- or AD model-related alterations in Ca2+ release from ryanodine receptors (RyR) on intracellular stores. The Ca2+-sensitive RyR channels amplify plasmalemmal Ca2+ influx by the mechanism of Ca2+-induced Ca2+ release (CICR). Considerable evidence indicates that a preferred functional link is present between L-VGCCs and RyRs which operate in series in heart and some brain cells. Here, we review studies implicating RyRs in altered Ca2+ regulation in cell toxicity, aging...

Combined effects of aging and inflammation on renin-angiotensin system mediate mitochondrial dysfunction and phenotypic changes in cardiomyopathies

Burks, Tyesha N.; Marx, Ruth; Powell, Laura; Rucker, Jasma; Bedja, Djahida; Heacock, Elisa; Smith, Barbara J.; Foster, D. Brian; Kass, David; O'Rourke, Brian; Walston, Jeremy D.; Abadir, Peter M.
Fonte: Impact Journals LLC Publicador: Impact Journals LLC
Tipo: Artigo de Revista Científica
Publicado em 18/05/2015 EN
Relevância na Pesquisa
36.59%
Although the effects of aging and inflammation on the health of the cardiac muscle are well documented, the combined effects of aging and chronic inflammation on cardiac muscle are largely unknown. The renin-angiotensin system (RAS) has been linked independently to both aging and inflammation, but is understudied in the context of their collective effect. Thus, we investigated localized cardiac angiotensin II type I and type II receptors (AT1R, AT2R), downstream effectors, and phenotypic outcomes using mouse models of the combination of aging and inflammation and compared it to a model of aging and a model of inflammation. We show molecular distinction in the combined effect of aging and inflammation as compared to each independently. The combination maintained an increased AT1R:AT2R and expression of Nox2 and exhibited the lowest activity of antioxidants. Despite signaling pathway differences, the combined effect shared phenotypic similarities with aging including oxidative damage, fibrosis, and hypertrophy. These phenotypic similarities have dubbed inflammatory conditions as premature aging, but they are, in fact, molecularly distinct. Moreover, treatment with an AT1R blocker, losartan, selectively reversed the signaling changes and ameliorated adverse phenotypic effects in the combination of aging and inflammation as well as each independently.

Live Long and Prosper; Aging in East Asia and Pacific

World Bank
Fonte: Washington, DC Publicador: Washington, DC
Tipo: Book; Publications & Research :: Publication; Publications & Research
EN_US
Relevância na Pesquisa
36.62%
This book discusses the societal and public policy challenges and reform options for the East Asia and Pacific countries as they address aging. The book aims to strike a balance between optimism and pessimism over aging. On the one hand, the impacts of aging on growth, labor markets, and public spending need not represent the unavoidable catastrophe sometimes feared. On the other hand, minimizing the downside risks of aging and ensuring healthy and productive aging will require proactive public policy, political leadership, and new mindsets across society.

An Assessment of Information & Assistance Services For Seniors Needing Long-term Care in North Carolina: What has changed and what comes next for the Aging Network?

Hayes, Ariel
Fonte: Universidade Duke Publicador: Universidade Duke
Tipo: Masters' project
Publicado em 22/04/2011 EN_US
Relevância na Pesquisa
36.65%
Policy Question: How should North Carolina’s Aging Network provide information and assistance services so that all older adults (and their caregivers) looking for long-term care receive appropriate guidance? Introduction: Information and Assistance (I&A) programs inform, counsel and connect people seeking long-term care with services that could meet their needs. The Older Americans Act mandated that every Area Agency on Aging (of which there are 17 in North Carolina) establish I&A programs in their region. North Carolina has 42 I&A programs registered with the Division of Aging and Adult Services; more counties offer these services without OAA funds. As the population ages, more people will need a well-informed, local agency is critical to help them navigate the long-term care system and access services. Older adults and their families face such a complicated array of choices and decisions – about not only health care, but also housing, finances, and basic household tasks. Ten years ago, the North Carolina Institute of Medicine (NCIOM) delivered its report, “A Long-Term Care Plan for North Carolina: Final Report” to the North Carolina Department of Health and Human Services (DHHS). Early in its deliberations, the Task Force concluded “one of its goals would be to propose a system that would allow consumers to find their way into and through the system with ease.” Once the state was awarded a Real Choice Systems Grant...