Modeling hematopoietic system response caused by chronic exposure to ionizing radiation.

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, erythrocytes, and platelets). The required model parameters were estimated based on available results of human and experimental animal studies. They include the steady-state number of hematopoietic stem cells and peripheral blood cell lines in an unexposed organism, amplification parameters for each blood line, parameters describing proliferation and apoptosis, parameters of feedback functions regulating the steady-state numbers, and characteristics of radiosensitivity related to cell death and non-lethal cell damage.

Early hematopoietic effects of chronic radiation exposure in humans.

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 3,200 hemograms taken for inhabitants of the Techa riverside villages over the years 1951-1956, i.e.

Modeling deterministic effects in hematopoietic system caused by chronic exposure to ionizing radiation in large human cohorts.

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 model describes the dynamics of the hematopoietic stem cell compartment as well as the dynamics of each of the three blood cell types (leukocytes, erythrocytes, and platelets). The model parameters are estimated from the results of other experiments.

Early hematopoiesis inhibition under chronic radiation exposure in humans.

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 (i.e.

Trade-off between cancer and aging: what role do other diseases play? Evidence from experimental and human population studies.

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.

Insights on aging and exceptional longevity from longitudinal data: novel findings from the Framingham Heart Study.

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 earlier in life affect the residual life span distribution. We used longitudinal limited access data from seven physiological indices and life spans of respective individuals collected in the Framingham Heart Study (FHS).

Cumulative index of health deficiencies as a characteristic of long life.

Objectives: To 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 aging-associated processes in older people.

Design: Retrospective cross-sectional and longitudinal studies.

Setting: The National Long-Term Care Survey (NLTCS) data that assessed health and functioning of U.