Cells somatic

D. Gmgei, Cell, Culture, and Somatic Cell Genetics, Vol 5, Academic Press, Inc., New York, 1988, pp. 435—448. 

A mutagen is a chemical that can induce alterations in the DNA. Mutations occurring in germ cells are inheritable and may lead to genetic diseases. If mutations take place in somatic cells, carcinogenesis may be initiated. 

ITowever, most normal somatic cells lack telomerase. Consequently, upon every cycle of cell division when the cell replicates its DNA, about 50-nucleotide portions are lost from the end of each telomere. Thus, over time, the telomeres of somatic cells in animals become shorter and shorter, eventually leading to chromosome instability and cell death. This phenomenon has led some scientists to espouse a telomere theory of aging that implicates telomere shortening as the principal factor in cell, tissue, and even organism aging. Interestingly, cancer cells appear immortal because they continue to reproduce indefinitely. A survey of 20 different tumor types by Geron Corporation of Menlo Park, California, revealed that all contained telomerase activity. 

Cellular therapies in transplantation and cancer are based on specific cells separated or sorted from human blood, bone marrow, or cord blood by means of their specific cell surface markers or cell differentiation antigens, e.g., CD3, CD4, CD8, CD 14, CD 19, and CD34. For example, the CD34+ stem cells, especially those derived from human embryos, have the capacity to differentiate in culture to generate different somatic cells, e.g., liver cells, heart cells, neurons, etc. This exploding field of research is now termed regenerative medicine. 

The eukaryotic somatic cell cycle is defined by a sequential order of tasks a dividing cell has to complete it must replicate its DNA, segregate its chromosomes, grow, and divide. The cell cycle can be divided into four discrete phases. DNA replication is restricted to S phase (DNA synthesis phase), which is preceded by a gap phase called G1 and followed by a gap phase called G2. During mitosis (M phase) the sister chromatids are segregated into two new daughter nuclei and mitosis is completed by the division of the cytoplasm termed cytokinesis (Fig. 1). 

A further committee. The Committee for Advance Therapies, is to be established under regulation (EC) No. 1394/2007 to deal with issues raised by emerging drug products based on gene therapy, somatic cell therapy and tissue engineering. 

The Competent Authorities are allowed a maximum of 60 days to review the data, or 90 days in the case of trials involving medicinal products for gene therapy, somatic cell therapy (including xenogeneic cell therapy), and all medicinal products containing genetically modified organisms. Such trials require written authorisation from the Competent Authority as distinct from other types of product where the authorities may just notify the sponsor of the acceptability (no-objection) of the application. If issues are raised, the sponsor may amend the application once, with a consequent extension to the allowed review period. 

Goate, A.M., Cooper, D.N., Hall, C., Leung, T.K., Solomon, E., Li, L. (1987). Localization of a human heat shock hsp70 gene sequence to chromosome 6 and detection of two other loci by somatic cell hybrid and RFLP analysis. Hum. Gen. 75, 123-128. 

Rains, D.W., Croughton, S.S. Croughan, T.P. (1986). Isolation and characterization of mutant cell lines and plants Salt tolerance. In Cell Culture and Somatic Cell Genetics of Plants, Vol. 3, ed. I. Vasil, pp. 537-47. New York Academic Press. 

The genetic constimtions of nearly all metazoan somatic cells are identical. 

The somatic cell gene replacement described above would obviously not be passed on to offspring. Other strategies to alter germ cell lines have been devised but have been tested only in experimental animals. A certain... 

Use of rodent or human somatic cell hybrids Permits assignment of a gene to one specific chromosome but not to a subregion. 

E. and Vlek-Noot, C. "The Use of Quantitative Cytochemlcal Analysis In Rapid Prenatal Detection and Somatic Cell Genetic Studies of Metabolic Diseases". Hlstochem. J.,... 

Fritsch, J. and Moraru, C. 1. (2007). Development and optimization of a carbon dioxide-aided cold microfiltration process for the physical removal of microorganisms and somatic cells from skim milk. /. Dairy Sci. 91, 3744-3760. 

Giffel, M. C. T. and Horst, H. C. V. D. (2004). Comparison between bactofugation and microfiltration regarding efficiency of somatic cell and bacteria removal. Bull. Int. Dairy Fed. 389, 49-53. 

Wieking, W. (2004). Removal of somatic cells from raw milk by state-of-the-art centrifugal technology. Bulletin of the International Dairy Federation 389, 45 7. 

J. Guern, J. P. Renaudin, S. C. Brown, The compartmentation of secondary metabolites in plant cell cultures. Cell Culture and Somatic Cell Genetics of Plants. Vol. 4 (F, Constabel and 1. K. Vasil, eds.). Academic Press, San Diego, 1987, p. 43. A. L. Samuels, M. Fernando, and A. D. M. Glass, Immunofluorescent localization of plasma membrane H -ATPase in barley roots and effects of K nutrition. Plant Physiol. 99 1509 (1992). 

Ciba-Geigy Ltd. 1983b. Sister chromatid exchange studies on somatic cells of Chinese hamsters TK 12 477 (REOLUBE HYD46). Test No. 830211. Ciba-Geigy Limited, Basle, Switzerland. 

VI3. Vora, S and Francke, U., Assignment of the human gene for liver-type 6-phosphofructokinase isozyme (PFKL) to chromosome 21 by using somatic cell hybrids and monoclonal anti-L antibody. Proc. Natl. Acad. Sci. U.S.A. 78,3738-3742 (1981). 

Buccione, R., Schroeder, A. C., and Eppig, J. J. (1990). Interactions between somatic cells and germ cells throughout mammalian oogenesis. Biol. Reprod. 43 543-547. 

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