Journal ArticlePhysiological genomics · May 2025
Glycated hemoglobin A1c (HbA1c) indicates average glucose levels over 3 mo and is associated with insulin resistance and type 2 diabetes (T2D). Longitudinal change in circulating HbA1c (ΔHbA1c) is also associated with aging processes, cognitive performance ...
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Journal ArticleAlzheimer's & dementia : the journal of the Alzheimer's Association · December 1, 2024
BACKGROUND: Results of recent analyses indicate that axon demyelination may play an important role in AD pathology. The MBP gene encodes a myelin basic protein involved in axon myelination in the nervous system including the central nervous system. Polymor ...
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Journal ArticleAlzheimer's & dementia : the journal of the Alzheimer's Association · April 2024
IntroductionLate-onset Alzheimer's disease (LOAD) has a strong genetic component. Participants in Long-Life Family Study (LLFS) exhibit delayed onset of dementia, offering a unique opportunity to investigate LOAD genetics.MethodsWe conduc ...
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Journal ArticleAlzheimers Dement (N Y) · 2024
INTRODUCTION: Alzheimer's disease (AD) is a neurodegenerative disorder characterized by declines in cognitive and functional severities. This research utilized the Clinical Dementia Rating (CDR) to assess the influence of tilavonemab on these deterioration ...
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Journal ArticleTheoretical population biology · October 2023
Research shows that geographic disparities in life expectancy between leading and lagging states are increasing over time while racial disparities between Black and White Americans have been going down. In the 65+ age strata morbidity is the most common ca ...
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Journal ArticleThe journals of gerontology. Series A, Biological sciences and medical sciences · August 2023
Mosaic chromosomal alterations (mCAs) are structural alterations associated with aging, cancer, cardiovascular disease, infectious diseases, and mortality. The distribution of mCAs in centenarians and individuals with familial longevity is poorly understoo ...
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Journal ArticleExp Gerontol · April 2023
OBJECTIVES: Health forecasting is an important aspect of ensuring that the health system can effectively respond to the changing epidemiological environment. Common models for forecasting Alzheimer's disease and related dementias (AD/ADRD) are based on sim ...
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Journal ArticleCancer Causes Control · September 2022
PURPOSE: To quantitatively evaluate contributions of trends in incidence, relative survival, and stage at diagnosis to the dynamics in the prevalence of major cancers (lung, prostate, colon, breast, urinary bladder, ovaries, stomach, pancreas, esophagus, k ...
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Journal ArticleInternational Journal of Bioinformatics Research and Applications · January 1, 2020
This study compares methods of imputing genetic markers, given a typed GWAS scaffold from the Long Life Family Study (LLFS) and latest reference panel of 1000-Genomes. We examined two programs for pre-phasing haplotypes MACH/SHAPEIT2 and MINIMAC/IMPUTE2 fo ...
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Journal ArticleMath Biosci · May 2019
A new model for disease prevalence based on the analytical solutions of McKendric-von Foerster's partial differential equations is developed. Derivation of the model and methods to cross check obtained results are explicitly demonstrated. Obtained equation ...
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Journal ArticleAsta Advances in Statistical Analysis · March 1, 2019
Frailty models allow us to take into account the non-observable inhomogeneity of individual hazard functions. Although models with time-independent frailty have been intensively studied over the last decades and a wide range of applications in survival ana ...
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Journal ArticleThe journals of gerontology. Series A, Biological sciences and medical sciences · October 2018
The special design of the Long Life Family Study provides a unique opportunity to investigate the genetics of human longevity by analyzing data on exceptional lifespans in families. In this article, we performed two series of genome wide association studie ...
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Journal ArticleExp Gerontol · September 2018
Longer lifespan is accompanied by a larger number of chronic diseases among older adults. Because of a growing proportion of older adults in the U.S., this brings the problem of age-related morbidity to the forefront as a major contributor to rising medica ...
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Journal ArticleAging · August 2018
The study of the genetics of longevity has been mainly addressed by GWASs that considered subjects from different populations to reach higher statistical power. The "price to pay" is that population-specific evolutionary histories and trade-offs were negle ...
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Journal ArticleExperimental gerontology · July 2018
BackgroundsElucidating the causal effects of common intermediate risk factors on the onset of age-related diseases is indispensable for developing prevention and intervention procedures.MethodsWe conducted two-stage time-to-event Mendelia ...
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Journal ArticleExperimental gerontology · July 2018
Despite evident success in clarifying many important features of Alzheimer's disease (AD) the efficient methods of its prevention and treatment are not yet available. The reasons are likely to be the fact that AD is a multifactorial and heterogeneous healt ...
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Journal ArticleJ Diabetes Complications · April 2018
AIMS: To identify how efforts to control the diabetes epidemic and the resulting changes in diabetes mellitus, type II (T2D) incidence and survival have affected the time-trend of T2D prevalence. METHODS: A newly developed method of trend decomposition was ...
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Journal ArticleAm J Hypertens · January 12, 2018
BACKGROUND: This study identifies the effect of intensive drug therapy (IDT) in individuals age 65+ with diabetes (type 2 diabetes mellitus (T2D)) and hypertension on all-cause death, congestive heart failure (CHF), hospitalization for myocardial infarctio ...
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Journal ArticleJ Alzheimers Dis · 2018
BACKGROUND: Trends in the prevalence of cognitive impairment (CI) based on cognitive assessment instruments are often inconsistent with those of neurocognitive disorders (ND) based on Medicare claims records. OBJECTIVE: We hypothesized that improved ascert ...
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Journal ArticleGenetic epidemiology · November 2017
Unraveling the underlying biological mechanisms or pathways behind the effects of genetic variations on complex diseases remains one of the major challenges in the post-GWAS (where GWAS is genome-wide association study) era. To further explore the relation ...
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Journal ArticleBioinformatics (Oxford, England) · October 2017
MotivationDespite recent advances of modern GWAS methods, it is still remains an important problem of addressing calculation an effect size and corresponding p-value for the whole gene rather than for single variant.ResultsWe developed an ...
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Journal ArticleTheor Popul Biol · April 2017
In this study, we present a new theory of partitioning of disease prevalence and incidence-based mortality and demonstrate how this theory practically works for analyses of Medicare data. In the theory, the prevalence of a disease and incidence-based morta ...
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Journal ArticleAging · April 2017
An ongoing debate in demography has focused on whether the human lifespan has a maximal natural limit. Taking a mechanistic perspective, and knowing that short telomeres are associated with diminished longevity, we examined whether telomere length dynamics ...
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Journal ArticleAging cell · February 2017
Traditionally, genomewide association studies (GWAS) have emphasized the benefits of large samples in the analyses of age-related traits rather than their specific properties. We adopted a realistic concept of genetic susceptibility to inherently heterogen ...
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Journal ArticleBMC bioinformatics · February 2017
BackgroundThe Stochastic Process Model (SPM) represents a general framework for modeling the joint evolution of repeatedly measured variables and time-to-event outcomes observed in longitudinal studies, i.e., SPM relates the stochastic dynamics of ...
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Journal ArticleThe journals of gerontology. Series A, Biological sciences and medical sciences · January 2017
BackgroundStudies of longevity-enriched families are an important tool to gain insight into the mechanisms of exceptionally long and healthy lives. In the Long Life Family Study, the spouses of the members of the longevity-enriched families are of ...
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Journal ArticleF1000Research · January 2017
We developed haploR, an R package for querying web based genome annotation tools HaploReg and RegulomeDB. haploR gathers information in a data frame which is suitable for downstream bioinformatic analyses. This will facilitate post-genome wid ...
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Journal ArticleF1000Research · January 2017
Simulation is important in evaluating novel methods when input data is not easily obtainable or specific assumptions are needed. We present cophesim, a software to add the phenotype to generated genotype data prepared with a genetic simulator. The o ...
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Journal ArticleMathematical Modelling of Natural Phenomena · January 1, 2017
It is well known that efficacy of immune functions declines with age. It results in an increase of severity and duration of respiratory infections and also in dramatic growth of risk of death due to these diseases after age 65. The goal of this work is to ...
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Journal ArticleBiogerontology · November 2016
The apolipoprotein E (apoE) is a classic example of a gene exhibiting pleiotropism. We examine potential pleiotropic associations of the apoE2 allele in three biodemographic cohorts of long-living individuals, offspring, and spouses from the Long Life Fami ...
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Journal ArticlePLoS genetics · November 2016
Gaining insights into genetic predisposition to age-related diseases and lifespan is a challenging task complicated by the elusive role of evolution in these phenotypes. To gain more insights, we combined methods of genome-wide and candidate-gene studies. ...
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Chapter · October 6, 2016
Age patterns of incidence rates of major circulatory diseases (CDs), their time trends, risk factors, and other characteristics capable of contributing to the debates on the role of aging in the deterioration of human health are investigated using standard ...
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Journal ArticleACM Bcb 2016 7th ACM Conference on Bioinformatics Computational Biology and Health Informatics · October 2, 2016
Stochastic Process Model has many applications in analysis of longitudinal biodemographic data. In general, such data contain various physiological variables (sometimes known as covariates or physiological indices). Longitudinal data can also contain genet ...
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Journal ArticleScientific reports · October 2016
Common strategy of genome-wide association studies (GWAS) relying on large samples faces difficulties, which raise concerns that GWAS have exhausted their potential, particularly for complex traits. Here, we examine the efficiency of the traditional sample ...
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Journal ArticleRejuvenation Res · June 2016
On the basis of the genotypic/phenotypic data from Chinese Longitudinal Healthy Longevity Survey (CLHLS) and Cox proportional hazard model, the present study demonstrates that interactions between carrying FOXO1A-209 genotypes and tea drinking are signific ...
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Journal ArticleMechanisms of ageing and development · June 2016
Contemporary longitudinal studies collect repeated measurements of biomarkers allowing one to analyze their dynamics in relation to mortality, morbidity, or other health-related outcomes. Rich and diverse data collected in such studies provide opportunitie ...
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ConferenceProceedings 2nd International Symposium on Stochastic Models in Reliability Engineering Life Science and Operations Management Smrlo 2016 · March 11, 2016
Connection between stress resistance and longevity in biological organisms is widely discussed and confirmed experimentally. Much less is known about the roles of genetic and non-genetic factors in regulation of such connection. Earlier studies emphasized ...
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Journal ArticleSci Rep · February 25, 2016
Only two genome-wide significant loci associated with longevity have been identified so far, probably because of insufficient sample sizes of centenarians, whose genomes may harbor genetic variants associated with health and longevity. Here we report a gen ...
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Journal ArticleBiogerontology · February 2016
Complex diseases are major contributors to human mortality in old age. Paradoxically, many genetic variants that have been associated with increased risks of such diseases are found in genomes of long-lived people, and do not seem to compromise longevity. ...
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Journal ArticleBiogerontology · February 2016
Increasing proportions of elderly individuals in developed countries combined with substantial increases in related medical expenditures make the improvement of the health of the elderly a high priority today. If the process of aging by individuals is a ma ...
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Journal ArticleFrontiers in public health · January 2016
While longitudinal changes in biomarker levels and their impact on health have been characterized for individual markers, little is known about how overall marker profiles may change during aging and affect mortality risk. We implemented the recently devel ...
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Journal ArticleNorth American actuarial journal : NAAJ · January 2016
Background and objectiveTo clarify mechanisms of genetic regulation of human aging and longevity traits, a number of genome-wide association studies (GWAS) of these traits have been performed. However, the results of these analyses did not meet ex ...
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Journal ArticleFrontiers in genetics · January 2016
Age-related diseases may result from shared biological mechanisms in intrinsic processes of aging. Genetic effects on age-related diseases are often modulated by environmental factors due to their little contribution to fitness or are mediated through cert ...
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Journal ArticleFrontiers in genetics · January 2016
This paper shows that the effects of causal SNPs on lifespan, estimated through GWAS, may be confounded and the genetic structure of the study population may be responsible for this effect. Simulation experiments show that levels of linkage disequilibrium ...
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Journal ArticleAnnals of gerontology and geriatric research · January 2016
A role of non-Mendelian inheritance in genetics of complex, age-related traits is becoming increasingly recognized. Recently, we reported on two inheritable clusters of SNPs in extensive genome-wide linkage disequilibrium (LD) in the Framingham Heart Study ...
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Chapter · January 1, 2016
The growth in interest in the biodemography of human aging, health, and longevity is motivated by the desire to better understand the factors and mechanisms responsible for age patterns and time trends in human mortality rates and survival curves. The avai ...
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Chapter · January 1, 2016
Age is a major risk factor for phenotypes characterizing human health, well-being, and survival in late life. The risks of these phenotypes expressed in forms of pathological dysregulation of physiological functions, incidence or prevalence of diseases, ca ...
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Chapter · January 1, 2016
The analyses conducted in Part I did not exhaust all factors affecting age patterns of age-related changes in health and mortality. They actually provided a strong rationale for conducting more detailed analyses which require advanced methods of mathematic ...
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Chapter · January 1, 2016
Longitudinal data play a pivotal role in discovering different aspects of knowledge related to aging, health, and longevity. There are many statistical methods for the analysis of longitudinal data, which is one of the most prolific areas of statistical sc ...
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Chapter · January 1, 2016
Life expectancy in humans worldwide has been experiencing dramatic increases for the past two centuries (Oeppen and Vaupel 2002). In most countries, the extension of lifespan is associated with a transition from a long historical period of high fertility a ...
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Chapter · January 1, 2016
It is well known from epidemiological research that values of indices describing physiological states at a given age may influence human morbidity and mortality risks. Studies of the connections between aging and life span suggest that the dynamic properti ...
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Chapter · January 1, 2016
Decades of studies of candidate genes show that they are not linked to aging-related traits in a straightforward manner. Recent genome-wide association studies (GWAS) have reached fundamentally the same conclusion by showing that traits in late life are li ...
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Chapter · January 1, 2016
Various approaches to statistical model building and data analysis that incorporate unobserved heterogeneity are ubiquitous in different scientific disciplines. Frailty models introduce the concept of unobserved or hidden heterogeneity in survival analysis ...
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Chapter · January 1, 2016
A better understanding of relationships among human aging, health, and longevity requires integrative statistical methods capable of taking into account relevant knowledge accumulated in the field when extracting useful information from the data. In this c ...
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Chapter · January 1, 2016
Despite broad interest in the mechanisms responsible for human aging and numerous efforts to identify factors contributing to morbidity, biological senescence, and longevity, these processes still remain elusive. This makes the systemic description of agin ...
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Chapter · January 1, 2016
Demographic calculations evaluating the role of chronic diseases in life expectancy use the assumption that diseases are independent. Disease independence was a plausible hypothesis in the era of infectious diseases. However, the health problems of modern ...
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Chapter · January 1, 2016
Longitudinal data on aging, health, and longevity provide researchers with a unique opportunity to observe aging-related changes in biomarkers that describe the functioning of individual organisms during people’s life courses. In this chapter, empirical es ...
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Chapter · January 1, 2016
The modern era of revolutionary advances in genetics provides great opportunities and challenges for the field of biodemography. We discuss approaches to work with the rich data available in modern longitudinal studies of aging, health, and longevity that ...
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Chapter · January 1, 2016
In a number of longitudinal studies, individual health and physiological/biological variables are repeatedly measured for a relatively large number of study subjects. Such data have good potential for evaluating properties of dynamic mechanisms involved in ...
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Chapter · January 1, 2016
The formulation of the recently developed Linear Latent Structures (LLS) analysis, its statistical properties, the algorithm for parameter estimation and its implementation, simulation studies, and application of LLS model to the National Long Term Care Su ...
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Chapter · January 1, 2016
Mortality rates are important characteristics of life span distributions that integrate the influences of many external and internal factors affecting individuals in the population during their life course. These include the ontogenetic program, individual ...
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Journal ArticleProc Natl Acad Sci U S A · July 28, 2015
Antiaging therapies show promise in model organism research. Translation to humans is needed to address the challenges of an aging global population. Interventions to slow human aging will need to be applied to still-young individuals. However, most human ...
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Journal ArticleJ Gerontol A Biol Sci Med Sci · April 2015
Logistic regression analysis based on data from 822 Han Chinese oldest old aged 92+ demonstrated that interactions between carrying FOXO1A-266 or FOXO3-310 or FOXO3-292 and tea drinking at around age 60 or at present time were significantly associated with ...
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Journal ArticleRejuvenation research · April 2015
The lack of evolutionary established mechanisms linking genes to age-related traits makes the problem of genetic susceptibility to health span inherently complex. One complicating factor is genetic trade-off. Here we focused on long-living participants of ...
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Journal ArticleLung Cancer · April 2015
OBJECTIVES: To evaluate the role of cardiovascular disease (CVD) comorbidity in survival of patients with non-small cell lung cancer (NSCLC). MATERIALS AND METHODS: The impact of seven CVDs (at the time of NSCLC diagnosis and during subsequent follow-up) o ...
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Chapter · March 26, 2015
The biodemography of mortality aims to explain observed age patterns and time trends in mortality rates from the biological point of view. It integrates knowledge about biological factors and mechanisms affecting mortality rates with demographic informatio ...
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Journal ArticleFrontiers in genetics · January 2015
BackgroundThe roles of genetic factors in human longevity would be better understood if one can use more efficient methods in genetic analyses and investigate pleiotropic effects of genetic variants on aging and health related traits.Data and ...
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Journal ArticlePloS one · January 2015
Insights into genetic origin of diseases and related traits could substantially impact strategies for improving human health. The results of genome-wide association studies (GWAS) are often positioned as discoveries of unconditional risk alleles of complex ...
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Book · October 9, 2014
Aging is a major risk factor for chronic diseases, which in turn can provide information about the aging of a biological system. This publication serves as an introduction to systems biology and its application to biological aging. Key pathways and process ...
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Journal ArticlePLoS genetics · January 2014
Enduring interest in the Apolipoprotein E (ApoE) polymorphism is ensured by its evolutionary-driven uniqueness in humans and its prominent role in geriatrics and gerontology. We use large samples of longitudinally followed populations from the Framingham H ...
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Journal ArticlePlos Genetics · January 1, 2014
Enduring interest in the Apolipoprotein E (ApoE) polymorphism is ensured by its evolutionary-driven uniqueness in humans and its prominent role in geriatrics and gerontology. We use large samples of longitudinally followed populations from the Framingham H ...
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Journal ArticleFrontiers in public health · January 2014
Longitudinal data on aging, health, and longevity provide a wealth of information to investigate different aspects of the processes of aging and development of diseases leading to death. Statistical methods aimed at analyses of time-to-event data jointly w ...
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Journal ArticleAdvances in geriatrics · January 2014
Biodemography became one of the most innovative and fastest growing areas in demography. This progress is fueled by the growing variability and amount of relevant data available for analyses as well as by methodological developments allowing for addressing ...
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Journal ArticleAnnals of gerontology and geriatric research · January 2014
BackgroundCorrecting for the potential effects of population stratification is an important issue in genome wide association studies (GWAS) of complex traits. Principal component analysis (PCA) of the genetic structure of the population under stud ...
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Journal ArticleESAIM. Probability and statistics = Probabilites et statistique : P & S · January 2014
We consider representations of a joint distribution law of a family of categorical random variables (i.e., a multivariate categorical variable) as a mixture of independent distribution laws (i.e. distribution laws according to which random va ...
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Journal ArticleJournal of Alzheimer's disease : JAD · January 2014
BackgroundThe ability to predict the length of time to death and institutionalization has strong implications for Alzheimer's disease patients and caregivers, health policy, economics, and the design of intervention studies.ObjectiveTo de ...
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Journal ArticleExp Gerontol · December 2013
Multi-morbidity is common among older adults; however, for many aging-related diseases there is no information for U.S. elderly population on how earlier-manifested disease affects the risk of another disease manifested later during patient's lifetime. Qua ...
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Journal ArticleExp Gerontol · August 2013
OBJECTIVES: Considering disease incidence to be a main contributor to healthy lifespan of the US elderly population may lead to erroneous conclusions when recovery/long-term remission factors are underestimated. Using two Medicare-based population datasets ...
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Journal ArticleAge Ageing · July 2013
OBJECTIVES: time trends of age-adjusted incidence rates of 19 ageing-related diseases were evaluated for 1992-2005 period with the National Long Term Care Survey and the Surveillance, Epidemiology and End RESULTS Registry data both linked to Medicare data ...
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Journal ArticleRes Aging · July 2013
Incidence rates of acute coronary heart disease (ACHD; including myocardial infarction and angina pectoris), stroke, and heart failure (HF) were studied for their age, disability, and comorbidity patterns in the U.S. elderly population using the National L ...
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Journal ArticleJ Gerontol A Biol Sci Med Sci · July 2013
This study focuses on the participants of the Long Life Family Study to elucidate whether biogenetic mechanisms underlying relationships among heritable complex phenotypes in parents function in the same way for the same phenotypes in their children. Our r ...
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Journal ArticleAge (Dordrecht, Netherlands) · April 2013
Studies focusing on unraveling the genetic origin of health span in humans assume that polygenic, aging-related phenotypes are inherited through Mendelian mechanisms of inheritance of individual genes. We use the Framingham Heart Study (FHS) data to examin ...
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Journal ArticleAging cell · April 2013
The inherent complexity of aging-related traits can temper progress in unraveling the genetic origins of healthspan. We focus on two generations in the Framingham Heart Study, the original (FHS) and offspring (FHSO) cohorts, to determine whether aging-rela ...
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Journal ArticleRejuvenation research · February 2013
Decades of studies of candidate genes show their complex role in aging-related traits. We focus on apolipoprotein E e2/3/4 polymorphism and ages at onset of cardiovascular diseases (CVD) and cancer in the parental and offspring generations of the Framingha ...
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Chapter · January 1, 2013
Age trajectories of mortality rates in human populations characterize individuals’ inequality in the duration of life. Various models of mortality rates are used in the analyses of survival data in demographic and epidemiological applications aiming to ide ...
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Journal ArticleFrontiers in genetics · January 2013
Background and objectiveThe influence of genes on human lifespan is mediated by biological processes that characterize body's functioning. The age trajectories of these processes contain important information about mechanisms linking aging, health ...
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Journal ArticleNorth American Actuarial Journal · December 1, 2012
The objective of this paper is to investigate dynamic properties of age trajectories of physiological indices and their effects on mortality risk and longevity using longitudinal data on more than 5,000 individuals collected in biennial examinations of the ...
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Journal ArticleRejuvenation research · August 2012
BackgroundIn genome-wide association studies (GWAS) of human life span, none of the genetic variants has reached the level of genome-wide statistical significance. The roles of such variants in life span regulation remain unclear.Data and meth ...
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Journal ArticleRejuvenation research · August 2012
Recently we have shown that the human life span is influenced jointly by many common single-nucleotide polymorphisms (SNPs), each with a small individual effect. Here we investigate further the polygenic influence on life span and discuss its possible biol ...
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Journal ArticleInternational journal of cancer · July 2012
High levels of circulating insulin-like growth factor-1 (IGF-1) have been associated with increased risk of several cancers. Regarding colorectal cancer, these associations are generally weak. We hypothesized that an increase in IGF-1 over time would be a ...
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Journal ArticlePhysics of life reviews · June 2012
A better understanding of processes and mechanisms linking human aging with changes in health status and survival requires methods capable of analyzing new data that take into account knowledge about these processes accumulated in the field. In this paper, ...
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Journal ArticleMath Biosci · March 2012
In this paper we present a new multiple-pathway stochastic model of carcinogenesis with potential of predicting individual incidence risks on the basis of biomedical measurements. The model incorporates the concept of intracellular barrier mechanisms in wh ...
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Journal ArticleJ Am Geriatr Soc · February 2012
OBJECTIVES: To use the Medicare Files of Service Use (MFSU) to evaluate patterns in the incidence of aging-related diseases in the U.S. elderly population. DESIGN: Age-specific incidence rates of 19 aging-related diseases were evaluated using the National ...
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Journal ArticlePloS one · January 2012
BackgroundVectorial capacity and the basic reproductive number (R(0)) have been instrumental in structuring thinking about vector-borne pathogen transmission and how best to prevent the diseases they cause. One of the more important simplifying as ...
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Journal ArticleScientifica · January 2012
We evaluated effects of the APOE polymorphism (carriers versus noncarriers of the e4 allele) and age trajectories of total cholesterol (CH) and diastolic blood pressure (DBP) on mortality risk in the Framingham Heart Study (original cohort). We found that ...
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Journal ArticleMathematical Population Studies · December 1, 2011
Data on individual health histories, age trajectories of physiological or biological variables, and mortality allow for the study of the joint evolution of health and physiological states and their effects on mortality. Individual health and physiological ...
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Journal ArticleAging cell · June 2011
Progress in unraveling the genetic origins of healthy aging is tempered, in part, by a lack of replication of effects, which is often considered a signature of false-positive findings. We convincingly demonstrate that the lack of genetic effects on an agin ...
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Journal ArticleRadiation and environmental biophysics · May 2011
A new model of the hematopoietic system response in humans chronically exposed to ionizing radiation describes the dynamics of the hematopoietic stem cell compartment as well as the dynamics of each of the four blood cell types (lymphocytes, neutrophiles, ...
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Journal ArticleMechanisms of ageing and development · April 2011
Recent studies have reported that leukocyte telomere length (LTL) is longer in offspring of older fathers. Longer telomeres might increase cancer risk. We examined the relation of father's age at the birth of the offspring (FAB) with LTL in the offspring i ...
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Journal ArticleMechanisms of ageing and development · April 2011
We used an approach of cumulative deficits to evaluate the rate of aging in 4954 participants of the Long-Life Family Study (LLFS) recruited in the U.S. (Boston, New York, and Pittsburgh) and Denmark. We used an array of 85 health-related deficits covering ...
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Journal ArticleBiogerontology · April 2011
Small sample size of genetic data is often a limiting factor for desirable accuracy of estimated genetic effects on age-specific risks and survival. Longitudinal non-genetic data containing information on survival or disease onsets of study participants fo ...
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Journal ArticleMechanisms of ageing and development · March 2011
We analysed relationship between the risk of onset of "unhealthy life" (defined as the onset of cancer, cardiovascular diseases, or diabetes) and longitudinal changes in body mass index, diastolic blood pressure, hematocrit, pulse pressure, pulse rate, and ...
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Journal ArticleAging · January 2011
Individuals from families recruited for the Long Life Family Study (LLFS) (n= 4559) were examined and compared to individuals from other cohorts to determine whether the recruitment targeting longevity resulted in a cohort of individuals with better health ...
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Journal ArticleComput Math Methods Med · 2011
Time trajectories of medical costs-associated with onset of twelve aging-related cancer and chronic noncancer diseases were analyzed using the National Long-Term Care Survey data linked to Medicare Service Use files. A special procedure for selecting indiv ...
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Journal ArticleThe journals of gerontology. Series A, Biological sciences and medical sciences · December 2010
BackgroundIdentification of gene variants that contribute to exceptional survival may provide critical biologic information that informs optimal health across the life span.MethodsAs part of phenotype development efforts for the Long Life ...
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Journal ArticleMedical decision making : an international journal of the Society for Medical Decision Making · November 2010
ObjectivesTo estimate and validate a multiattribute model of the clinical course of Alzheimer disease (AD) from mild AD to death in a high-quality prospective cohort study, and to estimate the impact of hypothetical modifications to AD progression ...
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Journal ArticleAging · September 2010
The results of genome-wide association studies of complex traits, such as life span or age at onset of chronic disease, suggest that such traits are typically affected by a large number of small-effect alleles. Individually such alleles have little predict ...
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Journal ArticleHealth physics · September 2010
The major goal of this study is to investigate and quantitatively describe the nature of the relationship between the characteristics of chronic exposure to ionizing radiation and specific patterns of hematopoiesis reduction. The study is based on about 3, ...
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Journal ArticleHealth physics · September 2010
A new model of the hematopoietic system for humans chronically exposed to ionizing radiation allows for quantitative description of the initial hematopoiesis inhibition and subsequent increase in the risks of late stochastic effects such as leukemia. This ...
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Journal ArticleRejuvenation research · August 2010
Relationships between aging, disease risks, and longevity are not yet well understood. For example, joint increases in cancer risk and total survival observed in many human populations and some experimental aging studies may be linked to a trade-off betwee ...
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Journal ArticleJournal of the American Geriatrics Society · July 2010
ObjectivesTo determine whether mean leukocyte telomere length (LTL) serves as a biomarker of disability assessed according to activities of daily living (ADLs) and what factors may modify this relationship.DesignRetrospective cross-sectio ...
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Journal ArticleBiogerontology · June 2010
Exceptional survival results from complicated interplay between genetic and environmental factors. The effects of these factors on survival are mediated by the biological and physiological variables, which affect mortality risk. In this paper, we evaluated ...
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Journal ArticleRadiation and environmental biophysics · May 2010
The major goal of this study was to identify and quantitatively describe the association between the characteristics of chronic (low-dose rate) exposure to (low LET) ionizing radiation and cellularity of peripheral blood cell lines. About 3,200 hemograms ( ...
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Journal ArticleMechanisms of ageing and development · May 2010
The Gln(27)Glu polymorphism but not the Arg(16)Gly polymorphism of the beta2-adrenergic receptor (ADRB2) gene appears to be associated with a broad range of aging-associated phenotypes, including cancers at different sites, myocardial infarction (MI), inte ...
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Journal ArticleMechanisms of ageing and development · March 2010
While there is evidence that longevity runs in families, the study of long-lived families is complicated by the fact that longevity-related information is available only for the oldest old, many of whom may be deceased and unavailable for testing, and info ...
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Journal ArticleStroke · March 2010
Background and purposeImprovements in recovery rates may contribute to an increase in healthy life expectancy. It is unclear, however, whether such changes take place because health researchers traditionally deal with changes in incidence and surv ...
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Journal ArticleRejuvenation research · February 2010
Multiple functions of the beta2-adrenergic receptor (ADRB2) and angiotensin-converting enzyme (ACE) genes warrant studies of their associations with aging-related phenotypes. We focus on multimarker analyses and analyses of the effects of compound genotype ...
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Journal ArticleCurr Gerontol Geriatr Res · 2010
It is well known from epidemiology that values of indices describing physiological state in a given age may influence human morbidity and mortality risks. Studies of connection between aging and life span suggest a possibility that dynamic properties of ag ...
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Journal ArticleInternational Journal of Low Radiation · January 1, 2010
This paper describes a new approach to modelling carcinogenesis, including that induced by ionising radiation. The specific feature of the developed approach is that the model, still adhering to the mutational theory of carcinogenesis, includes parameters ...
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Journal ArticleStatistics in medicine · January 2010
A correlated frailty model is suggested for analysis of bivariate time-to-event data. The model is an extension of the correlated power variance function (PVF) frailty model (correlated three-parameter frailty model) (J. Epidemiol. Biostat. 1999; 4:53-60). ...
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Journal ArticleExperimental gerontology · November 2009
We use unique experimental data on daily reproduction and survival of individual fruit flies from eight cohorts eclosed at different dates in 2004 and 2005 who were treated with varying proportions of sugar and yeast and subject to different caloric restri ...
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Journal ArticleDose-response : a publication of International Hormesis Society · October 2009
The idea of using hormesis for postponing aging and improving human health has been recently discussed in scientific literature. This paper shows that redundancy in renewal capacity, some portion of which become activated and manifested in hormesis effects ...
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Journal ArticleExperimental gerontology · September 2009
Exposure to mild heat-stress (heat-shock) can significantly increase the life expectancy of the nematode Caenorhabditis elegans. A single heat-shock early in life extends longevity by 20% or more and affects life-long mortality by decreasing initial mortal ...
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Journal ArticleMechanisms of ageing and development · September 2009
The levels of blood glucose (BG) in humans tend to increase with age deviating from the norm specified for the young adults. Such elevation is often considered as a factor contributing to an increase in risks of disease and death. The proper use of interve ...
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Journal ArticleJournal of theoretical biology · May 2009
Many longitudinal studies of aging collect genetic information only for a sub-sample of participants of the study. These data also do not include recent findings, new ideas and methodological concepts developed by distinct groups of researchers. The formal ...
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Journal ArticleMathematical biosciences · April 2009
The results of recent experimental and epidemiological studies provide evidence on the connection between carcinogenesis, cancer progression, and aging. Existing models, however, are traditionally focused only on one of these aspects of health deterioratio ...
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Journal ArticleExperimental hematology · April 2009
ObjectiveA central question in stem cell research is knowing the frequency of human hematopoietic stem cells (HSC) replication in vivo.Materials and methodsWe have constructed a model that characterizes HSC kinetics and the relative sizes ...
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Chapter · January 1, 2009
Mathematical modeling of immunosenescence is the new area of research emerging at the interface of the immunology, gerontology, and mathematics. In this paper we outline basic variables important for modeling aging immunity. We discuss the role of evolutio ...
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Journal ArticleComputational and Mathematical Methods in Medicine · January 1, 2009
Linear latent structure analysis is a new approach for investigation of population heterogeneity using high-dimensional categorical data. In this approach, the population is represented by a distribution of latent vectors, which play the role of heterogene ...
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Journal ArticleThe journals of gerontology. Series A, Biological sciences and medical sciences · January 2009
Aging studies can be facilitated by refocusing from longevity phenotypes to their proxies (intermediate phenotypes). Robust selection of the intermediate phenotypes requires data on such phenotypes and life span measured in the same individuals, which is n ...
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Journal ArticleMechanisms of ageing and development · January 2009
The potential gain in life expectancy which could result from the complete elimination of mortality from cancer in the U.S. would not exceed 3 years if one were to consider cancer independently of other causes of death. In this paper, we review evidence of ...
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Journal ArticleExperimental gerontology · December 2008
The traditional sex morbidity-mortality paradox that females have worse health but better survival than males is based on studies of major health traits. We applied a cumulative deficits approach to study this paradox, selecting 34 minor health deficits co ...
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Journal Article · December 1, 2008
Age patterns of incidence rates of major circulatory diseases (CDs), their time trends, risk factors, and other characteristics capable of contributing to the debates on the role of aging in the deterioration of human health are investigated using standard ...
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Journal ArticleThe journals of gerontology. Series A, Biological sciences and medical sciences · October 2008
We evaluated the predictive potential for long-term (24-year) survival and longevity (85+ years) of an index of cumulative deficits (DI) and six physiological indices (pulse pressure, diastolic blood pressure, pulse rate, serum cholesterol, blood glucose, ...
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Journal ArticleAnnals of epidemiology · September 2008
PurposeHealth of the general population is improving along a number of major health dimensions. Using a cumulative deficits approach, we investigated whether such improvements were evident at the level of minor health traits.MethodsWe sel ...
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Journal ArticleThe journals of gerontology. Series A, Biological sciences and medical sciences · July 2008
U-shaped dose-response relationships (hormesis) have been documented in numerous biological, toxicological, and pharmacological investigations. For example, in response to a mild 35 degrees C heat shock, the longevity of Caenorhabditis elegans exhibits an ...
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Journal ArticleJournal of the American Geriatrics Society · May 2008
ObjectivesTo compare how well frailty measures based on a phenotypic frailty approach proposed in the Cardiovascular Health Study (CHS) and a cumulative deficits approach predict mortality.DesignCohort study.SettingThe main cohor ...
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Journal ArticleAge and ageing · May 2008
Backgroundearly studies reported controversial findings on association of apolipoprotein E (APOE) polymorphism with disability.Objectiveto analyse sex-specific associations of APOE genotypes with impairments in (instrumental) activities o ...
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Journal ArticleMechanisms of ageing and development · April 2008
An important feature of aging-related deterioration in human health is the decline in organisms' resistance to stresses, which contributes to an increase in morbidity and mortality risks. In human longitudinal studies of aging, such a decline is not measur ...
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Journal ArticleJournal of the American Geriatrics Society · March 2008
OBJECTIVES: To reexamine a health-protective role of the common apolipoprotein E (APOE) polymorphism focusing on connections between the APOE epsilon2-containing genotypes and impairments in instrumental activities of daily living (IADLs) in older (> or = ...
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Journal ArticleRejuvenation research · February 2008
Major musculoskeletal conditions including arthritis represent an increasing burden on individuals and societies. We analyzed the association between self-reported arthritis and mortality in the U.S. elderly disabled and non-disabled individuals using uniq ...
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Journal ArticleTheoretical population biology · February 2008
Variables measured in longitudinal studies of aging and longevity do not exhaust the list of all factors affecting health and mortality transitions. Unobserved factors generate hidden variability in susceptibility to diseases and death in populations and i ...
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Journal ArticleJournal of the American Geriatrics Society · January 2008
ObjectivesTo investigate the relationship between body mass index (BMI) and 9-year mortality in older (> or = 65) Americans with and without disability.DesignCohort study.SettingThe unique disability-focused National Long Term Ca ...
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Journal ArticleAdvances in experimental medicine and biology · January 2008
In this chapter we review the epidemiology of hormone-associated cancers (prostate, breast, endometrial, ovarian, pancreatic and thyroid) paying special attention to the variability in the age patterns of cancer incidence rate over populations and time per ...
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Journal ArticleAnnals of the New York Academy of Sciences · November 2007
One of the most exciting events in current biogerontology is the elucidation of environmental control over the rate of aging. Many observations suggest that appropriate external stimuli can ameliorate the state of various biological entities and even rejuv ...
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Journal ArticleExperimental gerontology · October 2007
Cross-sectional analyses show that an index of aging-associated health/well-being deficits, called the "frailty index", can characterize the aging process in humans. This study provides support for such characterization from a longitudinal analysis of the ...
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Journal ArticleStatistics in medicine · September 2007
The aim of this study is to investigate the role of genetics and environment in susceptibility to breast cancer (frailty). An interdisciplinary approach was adopted, combining a correlated frailty-mixture model with genetic equations, allowing for decompos ...
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Journal ArticleMathematical biosciences · August 2007
Aging-related changes in a human organism follow dynamic regularities, which contribute to the observed age patterns of incidence and mortality curves. An organism's 'optimal' (normal) physiological state changes with age, affecting the values of risks of ...
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Journal ArticleJournal of the American Geriatrics Society · June 2007
ObjectivesTo describe the accumulation of aging-associated health disorders using a cumulative measure known as a frailty index (FI) and to evaluate its ability to differentiate long- and short-life phenotypes as well as the FI's connection to agi ...
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Journal ArticleBiogerontology · June 2007
The sample size of the data used in genetic studies is often a factor limiting the accuracy of statistical estimates. In this paper we suggest a new approach to evaluation of genetic influence on risk of development of aging-related health disorders. The a ...
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Journal ArticleBiogerontology · June 2007
The deterioration of human health with age is manifested in changes of thousands of physiological and biological variables. The contribution of some of such changes to the mortality risk may be small and cannot be reliably detected by existing statistical ...
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Journal ArticleMechanisms of ageing and development · March 2007
BackgroundWe employ an approach based on the elaborated frailty index (FI), which is capable of taking into account variables with mild effect on the aging, health and survival outcomes, and investigate the connections between the FI, chronologica ...
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Journal ArticleRejuvenation research · March 2007
The composite index constructed from longitudinal survey data as the level of deficits accumulated by an individual (frailty index) captures important systemic aspects of deterioration in a human organism, and is an attractive candidate for studying determ ...
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Journal ArticleAge (Dordrecht, Netherlands) · December 2006
Age trajectories of physiological indices contain important information about aging-related changes in the human organism and therefore may help us understand human longevity. The goal of this study is to investigate whether shapes of such trajectories ear ...
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Journal ArticleMechanisms of ageing and development · November 2006
BackgroundAn index of age-associated health/well-being disorders (deficits), called the "frailty index" (FI), appears to be a promising characteristic to capture dynamic variability in aging manifestations among age-peers. In this study we provide ...
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Journal ArticleExperimental gerontology · September 2006
Recent studies suggest that downregulation of tumor suppressor genes might not only favor cancer development but also postpone organisms' aging and increase longevity. However, there is lack of population-based studies directly supporting this idea. We stu ...
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Journal ArticleStroke · May 2006
Background and purposeStroke is associated with increased risk of dementia. There has been a decline in mortality from stroke among persons 65 and over in recent decades in the US. It is not clear, however, how this process has affected incidence ...
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Journal ArticleAnnals of the New York Academy of Sciences · May 2006
We suppose that natural aging derives from an inevitable shift in certain parameters of physiological control systems under the influence of inadequate environmental conditions, which are not able to fully induce an organism's "optimal" existence in the se ...
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Journal ArticleExperimental gerontology · March 2006
Age-specific mortality levels off at advanced ages in many species; one explanation for this phenomenon is provided by the population heterogeneity theory. Although mortality at advanced ages can be well fit by heterogeneity models, population heterogeneit ...
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Journal ArticleRadiats Biol Radioecol · 2006
In this paper we review recently-developed extension frailty, quadratic hazard, stochastic process, microsimulation, and linear latent structure models, which have the potential to describe the health effects of human populations exposed to ionizing radiat ...
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Journal ArticleAnnals of the New York Academy of Sciences · December 2005
Studies in mammals have led to the suggestion that hyperglycemia and hyperinsulinemia are important factors both in aging and in the development of cancer. Insulin/insulin-like growth factor 1 (IGF-1) signaling molecules linked to longevity include DAF-2 a ...
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Journal ArticleMathematical biosciences · November 2005
Frailty models are becoming increasingly popular in multivariate survival analysis. Shared frailty models in particular are often used despite their limitations. To overcome their disadvantages numerous correlated frailty models were established during the ...
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Journal ArticleNature reviews. Cancer · October 2005
Information obtained from animal models (mostly mice and rats) has contributed substantially to the development of treatments for human cancers. However, important interspecies differences have to be taken into account when considering the mechanisms of ca ...
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Journal ArticleThe journals of gerontology. Series A, Biological sciences and medical sciences · August 2005
Evolutionary theory postulates that there should be a robust relationship between fecundity and longevity. Prior work has generally supported this concept, but has not shed much light on the mechanisms at play. In preceding work, we have developed and veri ...
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Journal ArticleDemographic Research · May 13, 2005
Analysis of age-specific trajectories of cancer incidence rates for all sites combined (data source: International Agency for Research on Cancer) reveals a leveling-off and decline of the rates at old ages in different countries and time periods. We apply ...
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Journal ArticleDemographic Research · May 7, 2005
The overall cancer incidence rate declines at old ages. Possible causes of this decline include the effects of cross-sectional data that transform cohort dynamics into age patterns, population heterogeneity that selects individuals susceptible to cancer, a ...
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Journal ArticleThe international journal of biochemistry & cell biology · May 2005
The effects of new antidiabetic drug Diabenol (9-beta-diethylaminoethyl-2,3-dihydroimidazo-(1,2-alpha)benzimidazol dihydrochloride) on life span and spontaneous tumor incidence in NMRI and transgenic HER-2/neu mice as well as on colon carcinogenesis induce ...
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Journal ArticleMechanisms of ageing and development · March 2005
Classical evolutionary theory predicts the existence of genes with antagonistic effects on longevity and various components of early-life fitness. Quantitative genetic studies have provided convincing evidence that such genes exist. However, antagonistic p ...
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Journal ArticleTwin research and human genetics : the official journal of the International Society for Twin Studies · February 2005
Cause-specific mortality data on Danish monozygotic and dizygotic twins are used to analyze heritability estimates of susceptibility to coronary heart disease (CHD) after controlling for smoking and Body Mass Index (BMI). The sample includes 1209 like-sexe ...
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Journal ArticleTwin research and human genetics : the official journal of the International Society for Twin Studies · February 2005
Previous longevity studies of related individuals such as twins or siblings based on the major gene model have shown that the frequency and the relative risk of mortality of a beneficial allele in the population could be estimated. If, in addition to survi ...
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Journal ArticleHuman heredity · January 2005
Association-based linkage disequilibrium (LD) mapping is an increasingly important tool for localizing genes that show potential influence on human aging and longevity. As haplotypes contain more LD information than single markers, a haplotype-based LD app ...
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Journal ArticleVoprosy onkologii · January 2005
Female senescence accelerated mice SAMP-1. (prone) and SAMR-1 (resistant) were exposed 5 times a week monthly to melatonin (with drinking water 20mg/ml during the night hours) or to s.c. injections of epitalon (Ala-Glu-Asp-Gly) at a single dose 1mkg/mouse. ...
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Journal ArticleFrontiers in bioscience : a journal and virtual library · January 2005
In an earlier poster paper (1) we proposed that cancer can be viewed not only as a fatal disease but also as a local aberrant, rejuvenation, in an organism, and this fact can be useful for developing new anti-aging and anti-cancer treatments. In this paper ...
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Journal ArticleJournal of Biological Systems · December 1, 2004
We present two models suitable for describing dynamics of a population of unicellular organisms residing in chemostat. These models are based on biologically motivated Dynamic Energy Budget (DEB) theory and take into account the dynamics of mean energy res ...
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Journal ArticleBiophysics · December 1, 2004
The results of studying the life span and fertility of females of the Mediterranean fruit fly Ceratitis capitata suggest that an increase in the mean life span is accompanied by a proportional decrease in the mean number of eggs laid. At the same time, the ...
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Journal ArticleBehavior genetics · November 2004
The importance of some recognized risk factors on genetic influences for coronary heart disease (CHD) needs further clarification. The aim of the present study was therefore to study the impact of known risk factors on genetic influences for CHD-death. Bot ...
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Journal ArticleExperimental gerontology · October 2004
The purpose of this study is to investigate possible influences of different stressors (saline injections, light deprivation and constant light regimen) and geroprotectors (Epitalon and melatonin) on survivals of female HER-2/neu transgenic mice. We propos ...
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Journal ArticleInternational journal of cancer · September 2004
The effect of constant illumination on the development of spontaneous tumors in female CBA mice was investigated. Fifty female CBA mice starting from the age of 2 months were kept under standard light/dark regimen (12 hr light:12 hr dark; LD) and 50 CBA mi ...
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Journal ArticleBiofizika · September 2004
Analysis of experimental data on longevity and fertility of females of Mediterranean fruit fly Ceratitis capitata demonstrates that flies lay fewer eggs on the average as the average life-span increases. At the same time, the values of individual life-span ...
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Journal ArticleRussian Journal of Numerical Analysis and Mathematical Modelling · August 23, 2004
In this paper, we analyse the structure of equations in the earlier proposed mathematical model of the dynamics of age-related changes in population of peripheral T lymphocytes. To investigate behaviour of the model solutions in a wide range of values of v ...
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Journal ArticleCurrent Genomics · July 1, 2004
The amount of research on human aging and longevity has been growing rapidly in recent years. Multidisciplinary approaches, which integrate classic population genetics methods with the principles of epidemiological and demographic investigation, are emergi ...
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Journal ArticleAnnals of the New York Academy of Sciences · June 2004
Reproduction usually is characterized by a mean-population fecundity pattern. Such a pattern has a maximum at earlier ages and a subsequent gradual decline in egg production. It is shown that individual fecundity trajectories do not follow such a pattern. ...
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Journal ArticleAnnals of the New York Academy of Sciences · June 2004
There is an interesting divergence between the achievements of geriatrics and gerontology. On the one hand, during the last 30 years physicians in many developed countries have successfully prescribed several medicines to cure various symptoms of senescenc ...
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Journal ArticleAnnals of the New York Academy of Sciences · June 2004
Comparative analysis of malignant and senescent cells shows that their phenotypic features are in many instances contrary. Cancer cells do not "age"; their metabolic and growth characteristics are opposite to those observed with cellular aging (both replic ...
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Journal ArticleProceedings. Biological sciences · June 2004
Understanding the factors that determine the allocation and utilization of organism resources may provide an insight into the mechanisms of adaptation, ageing and reproduction. Resource allocation, which is regarded as a method of adaptation, increases fit ...
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Journal ArticleExperimental gerontology · May 2004
Heavy body weight (BW) is thought to be associated with reduced longevity and age-associated diseases, including cancer, both in laboratory rodents and humans. To further investigate the interactions between BW, longevity and spontaneous tumor development, ...
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Journal ArticleTwin research : the official journal of the International Society for Twin Studies · April 2004
The aim of this study was to investigate the role of genes and environment in susceptibility to breast cancer and to give an estimate of heritability in the propensity to develop the disease. To do this we applied an interdisciplinary approach, merging mod ...
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Journal ArticleExperimental gerontology · March 2004
There have been some observations that low body weight and a low level of some hormones (e.g. IGF-1) during the first half of life are predictors of longer life in mice. However, contradictions in the available data on the biomarkers of aging and predictor ...
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Journal ArticleBiogerontology · January 2004
Genetic variation plays an important role in natural selection and population evolution. However, it also presents geneticists interested in aging research with problems in data analysis because of the large number of alleles and their various modes of act ...
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Journal ArticleVoprosy onkologii · January 2004
Twenty five female HER-2/neu transgenic mice (FVB/N), aged 2 months, were surgically deprived of lighting; 30 intact transgenic mice, kept under standard conditions, were in control. Light deprivation was followed by inhibited intake of feed, decreased bod ...
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Journal ArticleZhurnal nevrologii i psikhiatrii imeni S.S. Korsakova · January 2004
Genetic predisposition is thought to exert a certain influence on the indices related to longevity and quality of life. Many of the indices, namely cognitive functioning, stress resistance, metabolism control, may be related to serotonin activity. To study ...
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Journal ArticleSozial- und Praventivmedizin · January 2004
ObjectivesTo analyse disability trends over the 1980s-1990s in gender and race groups of early retirement ages in USA.MethodsDisability trends for white and black males and females aged 65-69 and 70+ are analysed using the 1982-1999 NLTCS ...
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Journal ArticleBiogerontology · January 2004
An approach towards analyzing survivorship data is proposed for the study of changes in stress resistance with age in the population of Drosophila melanogaster. This is based on the model of heterogeneous mortality (frailty model). Results of the data anal ...
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Journal ArticleMechanisms of ageing and development · January 2004
This paper is the second one in a series of two papers hypothesizing and testing systemic grounds of reproductive life history in the female fruit fly. In the first paper, we analyzed mechanisms of individual fecundity scheduling and have drawn the followi ...
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Journal ArticleStatistics in medicine · December 2003
The genetic influence on susceptibility to diseases of the respiratory system and all-cause mortality was studied using data for identical (MZ) and fraternal (DZ) twins. Data from the Danish Twin Register include 1344 MZ and 2411 DZ male twin pairs and 147 ...
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Journal ArticleBiometrics · December 2003
We suggest a cure-mixture model to analyze bivariate time-to-event data, as motivated by the article of Chatterjee and Shih (2001, Biometrics 57, 779-786), but with a simpler estimation procedure and the correlated gamma-frailty model instead of the shared ...
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Journal ArticleBulletin of experimental biology and medicine · December 2003
Treatment of female SAMP-1 mice with Neuronol (drug containing succinic acid) given with drinking water starting from the age of 2 months during the whole life prolonged the lifespan and markedly reduced mortality of animals aged 1.5-2 years. Neuronol inhi ...
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Journal ArticleAnnals of the New York Academy of Sciences · December 2003
Phenotypic features of malignant and senescent cells are in many instances opposite. Cancer cells do not "age"; their metabolic, proliferative, and growth characteristics are opposite to those observed with cellular aging (both replicative and functional). ...
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Journal ArticleAnnals of human genetics · November 2003
In this paper, we apply logistic regression models to measure genetic association with human survival for highly polymorphic and pleiotropic genes. By modelling genotype frequency as a function of age, we introduce a logistic regression model with polytomo ...
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Journal ArticleDemographic Research · October 30, 2003
When individuals get older, the risk of many chronic diseases increases. This increase is in agreement with common theories of aging, such as mutation accumulation, wear and tear, antagonistic pleiotropy, etc. Surprisingly, however, the risk of some chroni ...
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Journal ArticleExperimental gerontology · October 2003
The human sirtuin 3 (SIRT3) gene encodes a putative mitochondrial NAD-dependent deacetylase (SIRT3) which belongs to the evolutionary conserved family of sirtuin 2 proteins. Studies in model organisms have demonstrated that SIR2 genes control lifespan, whi ...
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Journal ArticleMechanisms of ageing and development · June 2003
From the age of 3 months until their natural deaths, female Swiss-derived SHR mice were subcutaneously injected 5 consecutive days every month with 0.1 ml of normal saline (control) or with 2.5 microg/mouse (approximately 100 microg/kg) of delta-sleep indu ...
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Journal ArticleThe journals of gerontology. Series A, Biological sciences and medical sciences · June 2003
The age pattern of fecundity is represented as a result of a superposition of two processes: the genetic fecundity program encoded in the organism's reproductive machinery and senescence of the reproductive system. Accumulation of oxidative damage produces ...
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Journal ArticleMechanisms of ageing and development · May 2003
Reproduction is usually characterised by an average fecundity pattern having a maximum at earlier ages and a subsequent gradual decline later on. An individual fecundity trajectory does not follow such a pattern and has no maximum. A three-stage pattern, w ...
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Journal ArticleMechanisms of ageing and development · April 2003
In this paper, we presented the results of analysis of experimental evidence for the decline of the human immune system functioning with age using mathematical model of immunosenescence. The most prominent changes in this system are related to the decline ...
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Journal ArticleCancer letters · April 2003
We studied effect of pregnancy and ovariectomy on the development of mammary tumors in homozygous female HER-2/neutransgenic mice. The mean life span of uniparous mice was decreased by 16% in comparison to the control (P<0.05) and of mice which have two pr ...
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Journal ArticleExperimental gerontology · April 2003
From the age of 3 months until their natural death, female Swiss-derived SHR mice were given melatonin with their drinking water (2 or 20mg/l) for 5 consecutive days every month. Intact mice served as controls. There were 54 mice in each group. The results ...
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Journal ArticleInternational journal of cancer · January 2003
The effect of various regimens of treatment with melatonin on the development of mammary tumors in HER2/neu transgenic mice was investigated. Female HER-2/neu mice starting from the age of 2 months were kept under standard light/dark regimen and as given m ...
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Journal ArticleAdvances in gerontology = Uspekhi gerontologii · January 2003
The results of recent molecular biological studies of aging and longevity confirmed substantial genetic contribution to the life span. The analysis of these findings showed substantial role of specific mutations in genes involved in regulatory processes on ...
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Journal ArticleBiogerontology · January 2003
From the age of 3 months until their natural deaths, female outbred Swiss-derived SHR mice were subcutaneously injected on 5 consecutive days every month with 0.1 ml of normal saline (control) or with 1.0 microg/mouse (approximately 30-40 microg/kg) of tet ...
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Journal ArticleAdvances in gerontology = Uspekhi gerontologii · January 2003
Most studies of aging are conducted in humans and domestic or laboratory animals, i.e. in conditions where artificial environment protection is applied, This yields changes in physiology and behavior, which set up organism's state unobserved in wild life. ...
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Journal ArticleBiogerontology · January 2003
We propose a "protein and energy" free radical model of aging that predicts patterns of survival and fertility curves for Mediterranean fruit flies. Mathematical and simulation models of individual physiological processes were constructed in terms of stoch ...
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Journal ArticleBiogerontology · January 2003
The results of previous experimental studies of effects of antidiabetic biguanides (phenformin and buformin) on life span and spontaneous tumor incidence in mice and rats were recalculated and reanalyzed using standard demographic models of mortality. The ...
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Journal ArticleExperimental gerontology · October 2002
All the demographic surveys on the centenarians have highlighted that females outnumber males. The centenarians' male/female (M/F) ratio reported by most studies ranges between 1:4 and 1:7. A puzzling 1:2 ratio was observed in Calabria, a Southern Italian ...
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Journal ArticleStatistics in medicine · September 2002
In this paper a multivariate frailty model is suggested that can be used in the genetic analysis of the ageing process as a whole, simplified to consisting of the states 'healthy', 'disabled' and 'deceased'. The model allows us to evaluate simultaneously t ...
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Journal ArticleSocial biology · September 2002
Many researchers working in the area of aging and longevity base their conclusions on the behavior of empirical age trajectories of mortality rates. In such analyses, changes in the slope of the logarithm of the mortality curve are often associated with ch ...
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Journal ArticleJournal of internal medicine · September 2002
ObjectiveThe aim of the present study was to evaluate and distinguish between environmental and genetic effects for death from coronary heart disease (CHD) as well as to determine whether the importance of genetic influences is changing with age.< ...
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Journal ArticleBulletin of experimental biology and medicine · August 2002
Female transgenic FVB/N mice carrying the breast cancer gene HER-2/neu received epithalon (Ala-Glu-Asp-Gly) in a dose of 1 mg subcutaneously 5 times a week to from the 2nd month of life to death. Epithalon prolonged the average and maximum lifetimes of mic ...
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Journal ArticleMechanisms of ageing and development · July 2002
A new method based on the recently developed relative risk approach is introduced, and applied to data from Italian centenarian study (965 subjects aged from 13 to 109 years old) for investigating influences on longevity by Tyrosine Hydroxylase (TH) gene v ...
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Journal ArticleEvolution; international journal of organic evolution · June 2002
The general purpose of the paper is to test evolutionary optimality theories with experimental data on reproduction, energy consumption, and longevity in a particular Drosophila genotype. We describe the resource allocation in Drosophila females in terms o ...
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Journal ArticleThe journals of gerontology. Series A, Biological sciences and medical sciences · April 2002
As one aspect of the complex feature of longevity, gene by sex interaction plays an important role in influencing human life span. With advances in molecular genetics, more studies aimed at assessing gene by sex interaction are expected. New and valid stat ...
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Journal ArticleGene · March 2002
The human HRAS1 belongs to an evolutionarily-conserved family of genes which enrolls among its members the yeast RAS2, a gene which regulates stress response and longevity in the Saccharomyces cerevisiae. In this paper we report that the frequency of the a ...
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Journal ArticleMechanisms of ageing and development · March 2002
The parameters of the Gompertz approximation to the mortality curve are negatively correlated. Strehler and Mildvan [Science 132 (1960) 14] predicted this property of the mortality curve using a mathematical model of mortality and aging and then confirmed ...
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Journal ArticleThe journals of gerontology. Series A, Biological sciences and medical sciences · March 2002
In this paper we analyze survival data of populations of sterilized nematodes, Caenorhabditis elegans, exposed to heat shocks of different duration at the beginning of their adult lives. There are clear hormesis effects after short exposure to heat and cle ...
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Journal ArticleEuropean journal of human genetics : EJHG · February 2002
In this study, we introduce a centenarian-only approach to the assessment of gene-gene interaction that contributes to human longevity. This approach corresponds to the non-traditional case-only method in the genetic study of gene and disease associations. ...
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Journal ArticleStatistical Modeling · January 1, 2002
A mixture model in multivariate survival analysis is presented, whereby heterogeneity among subjects creates divergent paths for the individual’s risk of experiencing an event (i.e., disease), as well as for the associated length of survival. Dependence am ...
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ConferenceLecture Notes in Computer Science Including Subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics · January 1, 2002
The paper is focused on the interface design patterns for interactive modeling and it is an effort to systematically describe the usage of UID patterns in this area. Main objectives were to develop the UID patterns to increase the usability of the software ...
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Journal ArticleMathematical biosciences · January 2002
Manifestation of hormesis in longevity was modelled by modification of the mortality rate during and after the period of a stress factor action. In heterogeneous population this can lead to observation of unchanged mortality during action of the stress and ...
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Journal ArticleBiogerontology · January 2002
We consider a scheme of aging with two possible mechanisms of senescence processes: aging with apoptosis and necrosis for differentiated cells and a multistage process of malignant transformation. Our model describes the multistage phenomena of aging and c ...
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Journal ArticleClinical genetics · December 2001
The logistic regression model is a popular model for data analysis in epidemiological research. In this paper, we use this model to analyze genetic data collected from gene-longevity association studies. This new approach models the probability of observin ...
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Journal ArticleExperimental gerontology · December 2001
In this article, we discuss mechanisms responsible for the effects of heat treatment on increasing subsequent survival in the nematode worm Caenorhabditis elegans. We assume that the balance between damage associated with exposure to thermal stress and the ...
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Journal ArticleExperimental gerontology · December 2001
In 1960, Strehler and Mildvan (SM) theoretically predicted that the parameters of the Gompertz approximation to a mortality curve are negatively correlated. This means that the changes in the human mortality rate resulting from improvement in living standa ...
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Journal ArticleThe journals of gerontology. Series A, Biological sciences and medical sciences · October 2001
Three important results concerning the shape and the trends of the human mortality rate were discussed recently in demographic and epidemiological literature. These are the deceleration of the mortality rate at old ages, the tendency to rectangularization ...
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Journal ArticleTwin research : the official journal of the International Society for Twin Studies · October 2001
The intrauterine growth patterns for twins are characterized by normal development during the first two trimesters and reduced growth during the third trimester. According to the fetal origins hypothesis this growth pattern is associated with risk factors ...
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Journal ArticleMechanisms of ageing and development · September 2001
Stress experiments performed on a population of sterilised nematode worms (Caenorhabditis elegans) show a clear hormesis effect after short exposure and clear debilitation effects after long exposure to heat shock. An intermediate duration of exposure resu ...
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Journal ArticleMechanisms of ageing and development · September 2001
Patterns of human mortality share common traits in different populations. They include higher mortality in early childhood, lower mortality during the reproductive period, an accelerated increase of mortality near the end of the reproductive period, and de ...
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Journal ArticleExperimental gerontology · August 2001
This article investigates the relationship between the polymorphic variations in genes associated with cardiovascular disease and longevity in the Danish population. A new procedure that combines both demographic and the individual genetic information in d ...
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Journal ArticleTwin research : the official journal of the International Society for Twin Studies · August 2001
Data of the Danish Twin Registry on monozygotic and dizygotic twins are used to analyse genetic and environmental influences on susceptibility to heart diseases for males and females, respectively. The sample includes 7955 like-sexed twin pairs born betwee ...
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Journal ArticleMechanisms of ageing and development · July 2001
This paper reviews the recent literature on genes and longevity. The influence of genes on human life span has been confirmed in studies of life span correlation between related individuals based on family and twin data. Results from major twin studies ind ...
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Journal ArticleThe journals of gerontology. Series A, Biological sciences and medical sciences · July 2001
From the age of 6 months until their natural deaths, female CBA mice were given melatonin with their drinking water (20 mg/l) for 5 consecutive days every month. Intact mice served as controls. The results of this study show that the consumption of melaton ...
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Journal ArticleAnnals of human genetics · July 2001
In Danes we replicated the 3'APOB-VNTR gene/longevity association study previously carried out in Italians, by which the Small alleles (less than 35 repeats) had been identified as frailty alleles for longevity. In Danes, neither genotype nor allele freque ...
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Journal ArticleHuman genetics · March 2001
Allele epsilon4 of the nuclear APOE gene is a leading genetic risk factor for sporadic Alzheimer's disease (AD). Moreover, an allele-specific effect of APOE isoforms on neuronal cell oxidative death is known. Because of the role of the mitochondrial genome ...
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Journal ArticleBiogerontology · January 2001
New approaches are needed to explore the different ways in which genes affect the human life span. One needs to assess the genetic effects themselves, as well as gene-environment interactions and sex dependency. In this paper, we present a new model that c ...
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Journal ArticleMechanisms of ageing and development · January 2001
Fifty female CBA mice were injected s.c. either with 0.1 ml saline, or with synthetic thymic dipeptide Lys-Glu or with synthetic pineal tetrapeptide Ala-Glu-Asp-Gly both in a single dose of 0.1 microg/animal monthly for five consecutive days from the age o ...
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Journal ArticleBiogerontology · January 2001
The Rate of Living and the Threshold Theories of Aging are two contradicting approaches used to explain experimental facts about aging in fruit flies. In this paper we suggest an approach that unifies these theories and removes the contradiction. The appro ...
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Journal ArticleBiogerontology · January 2001
Survival data from Caenorhabditis elegans strain TJ1060 (spe-9; fer-15) following brief exposure to 35 degrees C have been investigated. Three experiments with 3-day-old worms were conducted with heat duration ranging between 0 and 12 hours. A statisticall ...
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Journal ArticleExperimental gerontology · October 2000
Empirical analysis of survival data obtained from large samples of Mediterranean fruit flies shows that the trajectory of the mortality rate for virgin females departs from that for females maintained in mixed sex cages. It increases, decelerates, reaches ...
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Journal ArticleExperimental gerontology · September 2000
Two general theories, i.e. "the network theory of aging" (1989) and "the remodeling theory of aging" (1995), as well as their implications, new developments, and perspectives are reviewed and discussed. Particular attention has been paid to illustrate: (i) ...
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Journal ArticleThe journals of gerontology. Series A, Biological sciences and medical sciences · August 2000
BackgroundFunctional abilities vary widely among elderly persons. The determinants of this variation are probably multiple and include normal aging processes as well as disease expression. This study estimates the relative importance of genetic an ...
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Journal ArticleThe journals of gerontology. Series A, Biological sciences and medical sciences · July 2000
In population studies of aging, the data on genetic markers are often collected for individuals from different age groups. The idea of such studies is to identify "longevity" or "frailty" genes by comparing the frequencies of genotypes in the oldest and in ...
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Journal ArticleTwin research : the official journal of the International Society for Twin Studies · March 2000
The traditional frailty models used in genetic analysis of bivariate survival data assume that individual frailty (and longevity) is influenced by thousands of genes, and that the contribution of each separate gene is small. This assumption, however, does ...
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Journal ArticleStudies in Health Technology and Informatics · January 1, 2000
Multivariate survival models are shown to be appropriate for the analysis of the genetic and the environmental nature of a human life-span. Models which involve continuously distributed individual frailty, play an important role in the genetic analysis of ...
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Journal ArticleMathematical Population Studies · January 1, 2000
Looking at survival in terms of biological indicators of aging has given rise to various models of mortality, some of which we review here. The most notable models are that of Strehler and Mildvan, which relates the force of mortality to the ability of org ...
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Journal ArticleThe journals of gerontology. Series A, Biological sciences and medical sciences · January 2000
We investigated the relation of the age trajectory of physiological indicators of the average metabolic activity of organisms in a population to the age-specific population mortality rate. We show that a metabolic rate indicator (MRI) can be estimated usin ...
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Journal ArticleJournal of Multivariate Analysis · November 1, 1999
A new class of bivariate survival distributions is constructed from a given family of survival distributions. The properties of these distributions are analyzed. It is shown that the same bivariate survival function can be derived using two radically diffe ...
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Journal ArticleAmerican journal of human genetics · October 1999
In population studies on aging, the data on genetic markers are often collected for individuals from different age groups. The purpose of such studies is to identify, by comparison of the frequencies of selected genotypes, "longevity" or "frailty" genes in ...
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Journal ArticleRussian Journal of Numerical Analysis and Mathematical Modelling · January 1, 1999
In this paper we attempt to show that it is possible to study an 'age-immune system-mortality' chain, using mathematical models of disease. We also give the results of parameterization of models of this type and formulate a problem of optimal control over ...
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Journal ArticleBehavior genetics · January 1999
Molecular epidemiological studies confirm tremendous variability in genetic and environmental susceptibility to disease and death for humans. This variability as well as the roles of genetic and environmental factors in susceptibility to death can be estim ...
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Journal ArticleJournal of epidemiology and biostatistics · January 1999
BackgroundMolecular epidemiological studies of aging and longevity are focused on evaluating the effects of single genes on susceptibility to disease and death. The effects of all genetic factors on susceptibility can be evaluated from the analysi ...
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Journal ArticleLifetime data analysis · January 1999
The interpretation of age-specific changes in hazards, relative risks, genetic parameters and other indicators of aging calculated from data on related individuals should take into account the regularities of bivariate selection. Due to such selection the ...
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Journal ArticleTwin research : the official journal of the International Society for Twin Studies · December 1998
Molecular epidemiological studies confirm a substantial contribution of individual genes to variability in susceptibility to disease and death for humans. To evaluate the contribution of all genes to susceptibility and to estimate individual survival chara ...
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Journal ArticleEuropean journal of human genetics : EJHG · November 1998
The possibility that four loci (REN, THO, PARP, SOD2) are associated with longevity was explored by comparing the genotypic pools of subjects older than 100 years with those of younger subjects matched for sex and geographic area (northern and southern Ita ...
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Journal ArticleScience · May 8, 1998
Old-age survival has increased substantially since 1950. Death rates decelerate with age for insects, worms, and yeast, as well as humans. This evidence of extended postreproductive survival is puzzling. Three biodemographic insights--concerning the correl ...
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Journal ArticleBehavior genetics · May 1998
The presence of familial and genetic effects in the Activities-of-Daily-Life (ADL) data collected in the first wave of the 1995 Longitudinal Study of Aging of Danish Twins (LSADT) older than 75 is tested using multithreshold liability models of disability ...
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Journal ArticleAnnals of human genetics · March 1998
The analysis of seven different age cohorts (697 individuals from 10 to 109 years old) revealed age-related changes in the 3'APOB-VNTR genotype pool. By recoding the 3'APOB-VNTR alleles into three size-classes (small, S, 26-34 repeats; medium, M, 35-39 rep ...
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Journal ArticleMathematical Population Studies · January 1, 1998
How do hidden physiological processes influence estimates of fecundability and sterility? Does unobserved heterogeneity play a role in these estimates? To address these questions mathematical models of the reproductive process are needed. It is not well kn ...
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Journal ArticleMathematical and Computer Modelling · April 1, 1997
Interventions to prevent disease and increase life expectancy are most effectively developed from data on pathways to disease and death. Unfortunately, most national data sets separate end-state information-i.e., cause-specific mortality-from pathway data ...
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Journal ArticleDemography · February 1997
In this paper we discuss an approach to the analysis of mortality and longevity limits when survival data on related individuals with and without observed covariates are available. The approach combines the ideas of demography and survival analysis with me ...
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Journal ArticleApplied Stochastic Models and Data Analysis · January 1, 1997
The use of maximum likelihood methods in analysing times to failure in the presence of unobserved randomly changing covariates requires constrained optimization procedures. An alternative approach using a generalized version of the EM-algorithm requires sm ...
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Journal ArticleStatistical Science · January 1, 1997
Stochastically changing covariates may inuence survival. They may be observed, unobserved or partly observed. We review the properties of hazard models explicitly representing the effects of unobserved, and partially observed, stochastic covariates. Such m ...
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Journal ArticleUgeskrift for laeger · December 1996
According to the foetal-origins hypothesis the risk of adult morbidity and mortality is heightened by intrauterine growth retardation. Twins, and in particular monozygotic twins, experience growth retardation in utero. A total of 8495 twin individuals born ...
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Journal ArticleMechanisms of ageing and development · June 1995
How long can people live? Opinions of the researchers diverge and debates continue. Is there any systematic way to address this question? In this paper, we suggest an approach to the estimation of the biological limit of human longevity using survival data ...
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Journal ArticleBMJ (Clinical research ed.) · February 1995
ObjectiveTo test the validity of the fetal origins hypothesis and the classic twin method.DesignFollow up study of pairs of same sex twins in which both twins survived to age 6.SettingDenmark.Subjects8495 twin individual ...
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Journal ArticleJournal of mathematical biology · January 1995
A model of human health history and aging, based on a multivariate stochastic process with both continuous diffusion and discrete jump components, is presented. Discrete changes generate non-Gaussian diffusion with time varying continuous state distributio ...
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Journal ArticleMathematical population studies · January 1995
"We develop a new model of bivariate survival based on the notion of correlated individual frailty. We analyze the properties of this model and suggest a new approach to the analysis of bivariate data that does not require a parametric specification--but ...
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Journal ArticleMathematical population studies · January 1995
"Many ideas in the analysis of heterogeneous mortality are based on the relationship between individual and observed hazard rates. This connection is established with the help of conditional averaging procedure: The observed risk of death at age x is calcu ...
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Journal ArticleGenetic epidemiology · January 1995
Population studies of changes in human morbidity and mortality require models which take into account the influence of genetic and environmental factors on life-related durations, such as age at onset of the disease or disability, age at death, etc. In thi ...
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Journal ArticleDemography · August 1994
This paper develops a multistate hazards model for estimating fecundability and sterility from data on waiting times to conception. Important features of the model include separate sterile and nonsterile states, a distinction between preexisting sterility ...
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Journal ArticleMechanisms of ageing and development · May 1994
Several alternative mortality models fit Swedish old-age mortality data equally well. The models build on two different concepts of the heterogeneity of individuals in a population. The first concept concerns fixed, genetic differences among individuals in ...
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Journal ArticleStochastic Processes and their Applications · January 1, 1994
Let Y=(Yt)t≥0) be an unobserved random process which influences the distribution of a random variable T which can be interpreted as the time to failure. When a conditional hazard rate corresponding to T is a quadratic function of cova ...
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Journal ArticleMathematical population studies · January 1993
"We present a mortality model where nationally representative survey data on risk factor distributions are combined with data on cohort mortality rates to increase information, i.e., a fixed marginal risk factor distribution is combined with a cohort model ...
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Journal ArticleTheoretical population biology · April 1989
This paper presents a model describing how the uncertainty due to influential exogenous processes combines with stochasticity intrinsic to physiological aging processes and propagates through time to generate uncertainty about the future physiological stat ...
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Journal ArticleStatistics in medicine · January 1988
The applicability of the theory of partially observed finite-state Markov processes to the study of disease, morbidity, and disability is explored. A method is developed for the continuous updating of parameter estimates over time in longitudinal studies a ...
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Journal ArticleMathematical population studies · January 1987
A stochastic differential equation model is developed to clarify the interaction of debilitation, recuperation, selection, and aging. The model yields various insights about the lingering mortality consequences of disasters such as wars, famines, and epid ...
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Journal ArticleMathematical Modelling · January 1, 1986
Analyses of the event histories of social and service utilization processes are often difficult because of a lack of adequate theory to specify the distributional form of any latent heterogeneity [J. Heckman and B. Singer, The identifiability of the propor ...
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Journal ArticleMathematical Modelling · January 1, 1986
In biostatistical, epidemiological and demographic studies of human survival it is often necessary to consider the dynamics of physiological processes and their influences on observed mortality rates. The parameters of a stochastic covariate process can be ...
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Journal ArticleJournal of mathematical biology · January 1986
Analyses of human mortality data classified according to cause of death frequently are based on competing risk theory. In particular, the times to death for different causes often are assumed to be independent. In this paper, a competing risk model with a ...
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Journal ArticleIEEE Transactions on Automatic Control · 1986
Necessary and sufficient conditions are established for convergence of Bayesian parameter estimators in a continuous-time adaptive Kalman filter with a denumerable or finite set of parameter values. ...
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Journal ArticleThe American statistician · August 1985
"As a cohort of people, animals, or machines ages, the individuals at highest risk tend to die or exit first. This differential selection can produce patterns of mortality for the population as a whole that are surprisingly different from the patterns for ...
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Journal ArticleTheoretical population biology · April 1985
Various multivariate stochastic process models have been developed to represent human physiological aging and mortality. These efforts are extended by considering the effects of observed and unobserved state variables on the age trajectory of physiological ...
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Journal ArticlePopulation Development Review · January 1, 1985
Data from China's 1982 one-in-a-thousand fertility survey are used to construct contour maps of Chinese marriage and fertility. They offer a panoramic view of the interaction of age, period, and cohort variations. The maps display long-term trends over the ...
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Journal ArticleGenus · January 1985
The authors construct contour maps of Italian male and female mortality rates for ages 0-79 for the years 1870-1979 using life table data from published sources. The maps "display persistent global and prominent local patterns of mortality, simultaneously ...
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Journal ArticleInternational Institute for Applied Systems Analysis, Research Report · December 1, 1983
The members of most populations gradually die off or drop out: people die, machines wear out, residents move out, etc. In many such aging populations, some members are more likely to die than others. Standard analytical methods largely ignore this heteroge ...
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Journal ArticleProblems of Information Transmission · January 1, 1983
The authors investigate the problem of interpolating a process with piecewise-continuous trajectories on the basis of observations of a multivariate point process. Equations are derived for the estimates and errors of direct and inverse interpolation in th ...
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Journal ArticleInternational Institute for Applied Systems Analysis Research Report · January 1, 1983
The members of most populations gradually die off or drop out: people die, machines wear out, residents move out, etc. In many such aging populations, some members are more likely to die than others. Standard analytical methods largely ignore this heteroge ...
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Journal ArticleRicerche Di Automatica · October 1, 1982
This paper is devoted to the problem of finding strong consistency conditions for denumerable and uncountable sets of parameter values in the continuous time stochastic observation process. It turns out that the consistency property is often equivalent to ...
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Journal ArticleIzvestia Vyssih Ucebnyh Zavedenij Priborostroenie · July 1, 1982
Two types of extrapolation are considered: the direct and inverse. Mesh equations are obtained for the first and second conditional moments assuming the observability of a multivariable process with gaussian compensators and the non-observability of a cont ...
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Journal ArticleProblems of Control and Information Theory · January 1, 1981
The paper investigates the necessary and sufficient conditions for consistency of parameter estimates in adaptive Kalman filtering. The unknown parameter is assumed to dictate the evolution of both the observed and unobserved processes and to take on value ...
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Journal ArticleProblems of Information Transmission · January 1, 1981
The consistency problem is investigated for estimates of the conditional expectation types for random variables with a countable set of values acording to observations of random processes in discrete time. Necessary and sufficient conditions for strong con ...
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Journal ArticleBulletin of the Academy of Sciences of the USSR Division of Chemical Science · July 1, 1978
1. The reaction of NiCl2 and CoCl2 with Al(i-Bu)3 in the presence of small amounts of dienes has been studied. 2. The reaction of NiCl2 with Al(i-Bu)3 in the presence of a diene results in the formatio ...
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Journal ArticleAvtomat I Telemekh · January 1, 1970
Optimal control of a Markovian step process is considered in the presence of observation cost. It is shown that the optimization procedure can be carried out by a method analogous to that described in Dynamic Programming and Markovian Processes by G. A. Ho ...
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Journal ArticleAvtomat I Telemekh · January 1, 1970
Formulas are derived for the a posteriori probabilities of a studied process. The methods developed may be considered a generalization of the methods based on the theory of conditional Markovian processes and developed for observing processes with continuo ...
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Journal ArticleAvtomat I Telemekh · January 1, 1970
Algorithms for approximate determination of the optimum estimates are devised. Examples are given. ...
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Journal ArticleAvtomat I Telemekh · January 1, 1969
Optimal methods of filtering step-function processes are investigated. It is shown that an optimal filter must be nonlinear. A system of equations is derived which permits the detection of current values of step-varying components of multidimensional proce ...
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Journal ArticleAkademiya Nauk Izvestiya Tekhnicheskaya Kibernetika · January 1, 1969
The choice of optimal observation process in a certain ensemble is investigated. It is shown that the solution of this problem reduces to the application of the maximum principle and subsequent solution of a boundary-value problem. ...
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Journal ArticleAvtomatika I Telemekhanika · January 1, 1969
Paper considers optimal control of observation; it is shown that this problem leads to use of usual methods of optimization for controls and functionals which depend on a posteriori characteristics. ...
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