Abstract:
:A mathematical model of cellular metabolism is used to relate the rates of cell division and waste production to the concentrations of oxygen and glucose in the medium in which a normal diploid cell culture is grown. The metabolic model in tandem with an earlier waste-content model based on the waste-product theory of aging provides a unified cell-culture model with which population size and intracellular waste content can be calculated. Population size is measured by the number of population doublings which have been achieved. After suitable adjustment of parameters in the metabolic model, maximum values of population size are calculated numerically with the use of the unified model. Results show that the population maxima are related in a plausible way to the oxygen and glucose concentrations. The effects of temperature changes and contact inhibition of growth are also simulated. Small changes in the cell-division and waste-production rates can cause transformation to unlimited growth in the waste-content model, but the unified model is not correspondingly sensitive to changes in the oxygen and glucose concentrations or to changes in temperature.
journal_name
Exp Gerontoljournal_title
Experimental gerontologyauthors
Hirsch HR,Witten Mdoi
10.1016/0531-5565(91)90073-usubject
Has Abstractpub_date
1991-01-01 00:00:00pages
549-67issue
6eissn
0531-5565issn
1873-6815journal_volume
26pub_type
杂志文章abstract::It is well established that the proliferative potential of the liver declines with aging. Epidermal growth factor (EGF)-stimulated DNA synthesis is reduced in hepatocytes from aged rats relative to young rats, and this reduction correlates with diminished activation of the extracellular signal-regulated kinase (ERK) p...
journal_title:Experimental gerontology
pub_type: 杂志文章
doi:10.1016/s0531-5565(02)00239-5
更新日期:2003-04-01 00:00:00
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journal_title:Experimental gerontology
pub_type: 杂志文章,评审
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journal_title:Experimental gerontology
pub_type: 杂志文章
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更新日期:2013-09-01 00:00:00
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journal_title:Experimental gerontology
pub_type: 杂志文章,随机对照试验
doi:10.1016/j.exger.2016.11.003
更新日期:2017-01-01 00:00:00
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journal_title:Experimental gerontology
pub_type: 杂志文章
doi:10.1016/0531-5565(83)90005-0
更新日期:1983-01-01 00:00:00
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journal_title:Experimental gerontology
pub_type: 杂志文章
doi:10.1016/j.exger.2003.10.011
更新日期:2004-02-01 00:00:00
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journal_title:Experimental gerontology
pub_type: 杂志文章
doi:10.1016/s0531-5565(97)00130-7
更新日期:1998-06-01 00:00:00
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journal_title:Experimental gerontology
pub_type: 杂志文章
doi:10.1016/j.exger.2019.01.011
更新日期:2019-04-01 00:00:00
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journal_title:Experimental gerontology
pub_type: 杂志文章
doi:10.1016/0531-5565(90)90006-n
更新日期:1990-01-01 00:00:00
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journal_title:Experimental gerontology
pub_type: 杂志文章
doi:10.1016/j.exger.2007.12.010
更新日期:2008-04-01 00:00:00
abstract:AIM:The present study investigated whether hypertension, blood pressure, and antihypertensive therapy were associated with frailty status in community-dwelling older adults. In addition, we tested whether such associations were consistent across different frailty instruments. MATERIAL AND METHODS:Two-hundred older adu...
journal_title:Experimental gerontology
pub_type: 杂志文章
doi:10.1016/j.exger.2021.111245
更新日期:2021-01-19 00:00:00
abstract::Post-viral pneumococcal pneumonia is a leading morbidity and mortality in older patients (≥65years of age). The goal of our current study is to understand the impact of chronological aging on innate immune responses to a secondary, post viral infection with Streptococcus pneumoniae, a causative agent of bacterial pneu...
journal_title:Experimental gerontology
pub_type: 杂志文章
doi:10.1016/j.exger.2017.11.010
更新日期:2018-05-01 00:00:00
abstract:OBJECTIVE:Senescent patients exhibit an elevated perioperative risk for cardiac dysfunction, hemodynamic depression and subsequent cardiac death compared to young patients. Despite the fact that a growing proportion of cardiac surgery patients are octogenarians, cardioplegic regimes remain comparable across patients of...
journal_title:Experimental gerontology
pub_type: 杂志文章
doi:10.1016/j.exger.2015.04.012
更新日期:2015-07-01 00:00:00
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journal_title:Experimental gerontology
pub_type: 杂志文章
doi:10.1016/j.exger.2019.110781
更新日期:2020-01-01 00:00:00
abstract::We have recently reported that activated mouse spleen mononuclear cells (MNCs) efficiently lyse autologous erythrocytes in vitro (Saxena and Chandrasekhar, 2000). In the present study, we have investigated erythrocyte-depleting ability (EDA) of spleen MNCs from young and old mice. Time kinetics of survival of erythroc...
journal_title:Experimental gerontology
pub_type: 杂志文章
doi:10.1016/s0531-5565(00)00091-7
更新日期:2000-05-01 00:00:00
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journal_title:Experimental gerontology
pub_type: 杂志文章,随机对照试验
doi:10.1016/j.exger.2015.03.011
更新日期:2015-06-01 00:00:00
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journal_title:Experimental gerontology
pub_type: 杂志文章
doi:10.1016/0531-5565(85)90038-5
更新日期:1985-01-01 00:00:00
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journal_title:Experimental gerontology
pub_type: 杂志文章
doi:10.1016/j.exger.2018.12.010
更新日期:2019-02-01 00:00:00
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journal_title:Experimental gerontology
pub_type: 杂志文章
doi:10.1016/j.exger.2013.04.007
更新日期:2013-08-01 00:00:00
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journal_title:Experimental gerontology
pub_type: 杂志文章
doi:10.1016/j.exger.2016.05.008
更新日期:2016-08-01 00:00:00
abstract::Stiffening of large elastic arteries with age increases the risk of cardiovascular diseases (CVD), but the underlying mechanisms are incompletely understood. We investigated the role of mitochondrial quality control (QC, i.e., mitophagy and biogenesis) in arterial stiffening with aging. In C57BL6 mice, aging was assoc...
journal_title:Experimental gerontology
pub_type: 杂志文章
doi:10.1016/j.exger.2014.07.008
更新日期:2014-10-01 00:00:00
abstract::Menopause is associated with a decline in overall health in women. One health aspect impacted is glucose metabolism. As women experience menopause, their metabolism declines dramatically. The current study addressed the influence of ovarian somatic cells on the improvement of metabolic health through transplantations ...
journal_title:Experimental gerontology
pub_type: 杂志文章
doi:10.1016/j.exger.2019.110686
更新日期:2019-10-15 00:00:00
abstract::This article addresses the description of several endocrine-related functions of the brain. It has emerged that steroids and growth factors may influence brain functions, and that brain cells may metabolize sex steroids. The crosstalk between different types of brain cells (neurons, astrocytes, the LHRH (luteinizing h...
journal_title:Experimental gerontology
pub_type: 杂志文章,评审
doi:10.1016/s0531-5565(96)00172-6
更新日期:1997-07-01 00:00:00
abstract::The aging of the skin is the most visible and obvious manifestation of organismal aging and may serve as a predictor of life expectancy and health. It is, however, also the human desire for long-lasting beauty that further raises interests in the topic, and thus considerable means and efforts are put into studying the...
journal_title:Experimental gerontology
pub_type: 杂志文章
doi:10.1016/j.exger.2019.110780
更新日期:2020-02-01 00:00:00
abstract::Age-related changes of immune functions have been extensively investigated in both humans and animal models; nevertheless, the literature on potential alterations of dendritic cells, potent antigen presenting cells responsible for initiating immune responses, with aging is very scarce. We studied the immuno-phenotype ...
journal_title:Experimental gerontology
pub_type: 杂志文章
doi:10.1016/s0531-5565(99)00089-3
更新日期:2000-03-01 00:00:00
abstract:OBJECTIVE:Depression is common in hemodialysis patients. Reduced DHEA-S levels have been shown to be associated with depression in general population. Abnormalities in hormone production and metabolism are found in hemodialysis patients. However, the association between DHEA-S levels and depression in hemodialysis pati...
journal_title:Experimental gerontology
pub_type: 杂志文章
doi:10.1016/j.exger.2009.08.009
更新日期:2009-11-01 00:00:00
abstract::It has been suggested that alterations in Na(+),K(+)-ATPase mediate the development of several aging-related pathologies, such as hypertension and diabetes. Thus, we evaluated Na(+),K(+)-ATPase function and H(2)O(2) production in the renal cortex and medulla of Wistar Kyoto (WKY) rats at 13, 52 and 91 weeks of age. Cr...
journal_title:Experimental gerontology
pub_type: 杂志文章
doi:10.1016/j.exger.2010.09.012
更新日期:2010-12-01 00:00:00
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journal_title:Experimental gerontology
pub_type: 杂志文章,多中心研究
doi:10.1016/j.exger.2015.06.018
更新日期:2015-10-01 00:00:00
abstract::Engineering of fetal tissue has a high potential for the treatment of acute and chronic wounds of the skin in humans as these cells have high expansion capacity under simple culture conditions and one organ donation can produce Master Cell Banks which can fabricate over 900 million biological bandages (9 x 12cm). In a...
journal_title:Experimental gerontology
pub_type: 杂志文章
doi:10.1016/j.exger.2008.11.004
更新日期:2009-03-01 00:00:00
abstract:OBJECTIVE:Aging has been reported to be associated with changes in immune function. Although frequent infection and the development of malignancy suggest the decline of immune function with aging, changes toward proinflammatory conditions also develop at the same time. Th17 cells are well known CD4(+) T cell subpopulat...
journal_title:Experimental gerontology
pub_type: 杂志文章
doi:10.1016/j.exger.2013.10.006
更新日期:2014-01-01 00:00:00