Culture medium manipulation, effect

During development of chicken skeletal muscle cells, the marked increase in Ca transport of sarcoplasmic reticulum, observed both in vivo and in vitro systems, can be interpreted mainly as the result of an increase in the concentration of Ca transport ATPase. Changes in the fatty acid composition of muscle membranes developed in vivo occur with a balance between chain length and unsaturation, without affecting significantly their Ca permeability. In cultured muscle cells their fatty acid composition can be manipulated to a great extent by lipid supplementation of the culture medium. The effects of these in vitro modifications in lipid composition on the calcium transport function of muscle membranes should be investigated. 

Hairy roots are not as readily manipulated by altering culture conditions or pH as are suspension cultures. However, the effect of temperature on growth and hyoscyamine production in transformed root cultures of Datura stramonium has been demonstrated by Hilton and Rhodes [86]. Another way to enhance the secondary metabolite accumulation of hairy roots is the addition of precursors and/or metabolic intermediates to the growth medium. The addition of (R,S)- phenyllactic acid increased significantly the accumulation of hyoscyamine and scopolamine in the hairy root culture of Datura Candida x D. aurea [72]. 

Table III gives the results of an experiment in which the effect of serum manipulation on sulfolipid synthesis by dissociated brain cells was examined. The cells isolated from the embryonic mouse brain were grown on the medium containing calf serum (20%) for 3 days by which time most of the cells would have attached to the substratum. On the 4th day, the medium was replaced by fresh medium containing calf serum, calf serum + 13(2 x 10 8m), hypothyroid calf serum, or hypothyroid calf serum + 13(13 ng/ml). Cultures were grown for another week and then labeled with 400 pCi for 16 h. The lipids...

Naturally, the modem shaman will have to search for means of fulfilling his psychopompic functions, which are different from the relatively straightforward ritualistic techniques of his predecessor. One of the most potentially effective of such means lies in his artistic and poetic capacities the soul of modem humanity is still open to influence by aesthetic means. Hence one of the first places we should look for signs of a modem shamanism is in the artistic sphere. The shamanic role of the artist in modem cultures extends not only to his work, but to his very life. Through manipulation of his physical medium, the artist seeks to express his personal... 

This technique is very discriminating and not too expensive, but it is long and requires several complex manipulations. It is useful for the subtle characterization of a small number of sfiains. Inoculation effectiveness can also be verified by this method. To verify an inoculation, a sample is taken during or towards the end of alcoholic fermentation. In the laboratory, the lees are placed in a liquid medium culture. The mtDNA restriction profile of this total biomass and of the yeast starter strain are compared. If the restriction profile of the sample has no supernumerary bands with respect to the yeast starter strain profile, the yeast starter has been properly implanted, with an accuracy of 90%. In fact, in the case of a binary mixture, the minority strain must represent around 10% of the total population to be detected (Hallet et al., 1989). 

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