Tissue Culture Studies

There is ample evidence from both animal experiments and tissue cultures studies to show that brassica vegetables and their constituents selectively induce Phase II enzymes. Evidence for the induction of Phase II enzymes by... 

Population studies associate tomato consumption with reduced risk to prostate cancer. The most positive associations have come from cohort studies performed before the prostate-specific antigen (PSA)-screening era, and these studies have suggested that the tomato/lycopene effect was the strongest for clinically relevant prostate cancers (Giovannucci 2007). Small human studies have shown in vivo antioxidant effects for tomato products but evidence for lycopene alone is weak (Chen et al. 2001, Porrini and Riso 2000, Riso et al. 2004, Zhao et al. 2006). Animal and tissue culture studies have been... 

Gey GO, Coffman WD, Kubicek MT. Tissue culture studies of the proliferative capacity of cervical carcinoma and normal epithelium. Cancer Res 12 364—365 (1952). 

Fetner has also demonstrated chromatid breaks in a human tissue-culture cell line exposed to ozone at 8 ppm for 5 min. Other tissue-culture studies include that of Sachsenmaier et who noted tetraploidy and other chromosomal abnormalities in embryonic chick fibroblasts exposed to ozone and a decrease in transplantability of mouse ascites tumor cells. In addition, Pace et demonstrated an interference by ozone with mitotic activity in two tissue-culture cell lines. More recently, Booher et al. reported that lung cells exposed in culture to ozone concentrations as low as 0.3 ppm demonstrated an inhibition in growth that was proportional to the ozone concentration. 

Tissue culture studies (cell line selection)... 

S-Methylmalonyl-CoA mutase (EC 5.4.99.2) is a deoxyadenoxyladen-osylcobalamin-dependent enzyme of mitochondria required to catalyze the conversion of methylmalonyl-CoA to succinyl-CoA. A decrease in the activity of methylmalonyl-CoA mutase leads to the urinary excretion of large amounts of methylmalonic acid (C22). The biochemical lesion may be at the mutase level due to an abnormality of apoenzyme protein or an inability to elaborate the required coenzyme form of vitamin B12> i.e., adenosyl-cobalamin. In rare cases the abnormality may be due to an inability to convert the d form of methylmalonyl-CoA mutase to the l form as a result of a defective racemase (EC 5.1.99.1) (Kll). In patients, the nature of the abnormality can be determined by tissue culture studies (D13) and by clinical trial, since patients with a defect in adenosylcobalamin production will show clinical improvement when treated with very large doses of vitamin B12 (Mil). 

Bischoff, R. (1979). Tissue culture studies on the origin of myogenic cells during muscle regeneration in the rat. In... 

Micropropagation systems mentioned previously (Method I and Method II) require two different cultural steps, shoot multiplication and rooting. In the course of tissue culture studies of ipecac, adventitious shoot formation on cultured root had been incidentally found. Therefore, one step micropropagation system of ipecac was established through adventitious shoot formation on the cultured root [14]. 

The in vivo observations are complemented by studies examining microglial activation in vitro. Tissue culture studies have revealed an important microglial property which changes as a result of cell activation, namely, microglial secretory activity. Numerous studies have reported that cultured microglial cells can produce... 

L14. Liveson, J. A., Gardner, J., and Bomstein, M. B., Tissue culture studies of possible uremic neurotoxins Myoinsoitol. Kidney Int. 12, 131-136 (1977). 

USE In investigation of the structure and biosynthesis of collagen in dispersion of cells for tissue culture studies. 

The responses of neural crest cells to VN are directed against the RGD sequence, but appear from tissue culture studies to be complex. The ctV in-tegrin appears to combine with 8 1, 3 and 5 in-tegrins to give three active VN receptors, and it has been suggested that the different combinations differentially affect cell adhesion and cell migration (Delannet et al, 1994). The role of VN, however, is still obscure and no in vivo testing has been performed. 

These pioneering tissue culture studies clearly documented that certain extracellular factors were capable of re-directing the biochemical choices of neurons previously committed to another neurotransmitter pathway. A comparable role for differentiation factors in vivo is supported by the work of Landis and colleagues (for review see, Landis,... 

Cell and tissue culture studies on OP-induced neurotoxicity are valuable if they provide valid insights into processes that occur in vivo. The extrapolation of /n vitro results to animals and human populations requires careful attention to four elements of experimental de.sign in vitro (Fig. 2). First, concentrations in vitro must be valid and comparable to toxicological doses. Unfortunately, little information is available on the brain concentnitions of OP compounds that arc... 

If an initiated cell for some reason does not progress into subsequent stages of events, and the state of initiation does not revert back towards normality, the cells will retain their potential for malignant conversion. There is evidence from cell and tissue culture studies that varying degrees of reversion towards normality appear to occur, but that it may well not be complete in the sense that some initiated cells are likely to replicate indefinitely in the future, retaining their state of initiation and thus their potential for malignant conversion. 

Tobacco is one of the major model systems in plant cell and tissue culture studies. Particularly in developing techniques for genetic engineering has it played a major role. Consequently numerous papers have described various aspects of tobacco plant biotechnology. For example, almost 200 entries for plant cell culture media for tobacco are given in the tabulation by George et al. 189). Some of the most commonly used media for plant cell cultures were, in fact, developed for tobacco callus cultures 190,191). Indeed, root cultures of several Nicotiana species were described as early as 1938 by White 192). Collins and Legg 193) reviewed the use of cell and tissue culture methods for the improvement of tobacco. 

As seen in Figure 7.6 (a-d), the interconnections in coalescence pores are different compared with those of the primary pores. In order to have primary pore structure in the presence of additives/fillers, the concentration of the additives must be low. The example below illustrates one such case. In this example, the aqueous phase contains 0.5 wt.% hydroxyapatite dissolved in 15% phosphoric acid solution. After emulsification and polymerization, PHP is soaked in 1 M NaOH to precipitate hydroxyapatite and subsequently washed in water to obtain pH = 7. These materials are then washed in isopropanol to remove residual surfactant, toxic monomer residues, and electrolytes. Polymer samples were finally dried in a vacuum oven and then sterilized in an autoclave before use as support in micro-bioreactors or tissue culture studies. 

---