In Vitro Cellular & Developmental Biology: Journal of the Tissue Culture Association
Human microvascular endothelial cells (HMVEC) from adult adipose tissue were cultured in MCDB 131 medium supplemented with 10% fetal bovine serum. Under these conditions, HMVEC from seven different donors had finite proliferative life spans ranging from 14.5 to 23.5 population doublings (PD), with a mean life span of 19 PD. Addition of 10% conditioned medium from activated human leukocyte cultures (BM Condimed) extended the life span of HMVEC to 31 to 41 PD, with a mean life span of 37 PD.
The idea that putrefaction of the stools causes disease, i.e., intestinal autointoxication, originated with physicians in ancient Egypt. They believed that a putrefactive principle associated with feces was absorbed in to the general circulation, where it acted to produce fever and pus. This description of the materia peccans represented the earliest forerunner of our present notion of endotoxin and its effect.
The desire for the extension of life is not one out of many desire in life, but a form of the fundamental desire for life itself. This so called 'categorical desire' is a necessary condition for the many desires in life. The question why we desire for life (and for its extension), is the question for the meaning of life. The searching for a 'natural lifespan' is meaningless when it wants to find in nature a given norm for the duration of life. It can only have meaning when it tries to formulate the conditions for the experience of life as successful and meaningful.
Abortion, primarily as a measure of population control, certainly continues to be an emotional, frustrating and stressful event. In continuation of our work on stressful situations in the female life span and biochemical parameters, serum lipid peroxide levels in terms of malondialdehyde (nmol/ml) have been determined in females undergoing abortion [suction curettage (n = 30), Emcredil-induced abortion (n = 30) and spontaneous abortion (n = 40)] and were compared with appropriate gestational controls.
Human diploid fibroblasts, strain MRC-5, were sequentially irradiated with 60Co gamma rays at intervals during their in vitro lifespan. The results indicate that 3 or 6 doses of 1 Gy can increase lifespan, and the same was true for cells treated with 3 doses of 3 Gy. Higher doses (5 x 3 Gy) did reduce growth potential, suggesting either that mid-late passage cells become more sensitive to radiation, or that doses beyond a given threshold reduce population lifespan by multiple cellular hits. The life extension induced by gamma rays might be due to an induced hypermethylation of DNA.
Infection of normal human diploid fibroblasts (HF) with the DNA tumor virus simian virus 40 (SV) leads to an extension of lifespan and concomitant increase in the levels of the viral large tumor antigen (T antigen) and the cellular protein p53. The intracellular localization of T antigen and p53 was mostly nuclear in both SVpre-crisis and SVpost-crisis cells, however certain population doubling (PD) of the SVpre-crisis cells exhibited some cytoplasmic staining. The DNA content of SVpre-crisis cells shifted to tetraploidy and the SVpost-crisis cells were near-tetraploid.
Table 1 summarizes the activities of hemopoietins on immature and mature basophils. IL-3, GM-CSF, and IL-5 enhanced basophil histamine release and in-vitro survival, while G-CSF, M-CSF, and IL-4 had no enhancing activities at all. In addition, IL-3 and GM-CSF induced basophil chemotaxis.
Lymphocytes have a finite and predictable proliferative life span in culture similar to that observed in fibroblasts. In general, the senescence of human fibroblasts is inevitable and irreversible, but their proliferative life span can be extended by certain DNA tumor virus oncogenes, such as the large T antigen of the SV40 virus. Here, we show that human T lymphocytes (HTL) can be stably transfected with SV40 large T and that expression of T antigen extended the life span of T cell cultures.
We applied the Weibull distribution to the life-table and age-patterns of diseases in Japan. The life-table follows a composite Weibull distribution composed of initial failure and two stage wear-out failure periods. The extension of lifespan during the past century is manifested as increases in the scale parameters in all three periods and the shape parameters in the wear-out periods with female predominancy. The shape parameters of diseases show time-independent sex-dependent specific values.