Cultured and isolated cells

Cultured rat vascular smooth muscle cells (VSMCs), grown and prepared for respirometry as described in Doeller et al, 2005 [41], were injected into the respirometer chamber to a concentration of between 10 and 10 cells ml Cell viability remained at 90% throughout experiments. Near 4pM O2, H2S production was stimulated by the addition of L-cysteine and PLP (Fig. 8.8). The initial H2S production rate was approximately 20% of the rat aorta homogenate rate. H2S production rate decreased after the initial rise in H2S concentration, perhaps the result of product feedback inhibition. The addition of the CGL inhibitor BCA showed an effect similar to aorta homogenate. 

Isolated primary rat hepatocytes in the respirometer chamber at 10 cells ml exhibited robust H2S production, achieving concentrations of 20pM in 30min as the O2 concentration decreased and in the presence of L-cysteine and PLP (Kraus et al, preliminary data, not shown). Inhibitors of both CBS and CGL (amino oxyacetic acid and propargylglycine, respectively) inhibited H2S production, indicating the presence of both enzymes in hepatocytes. 

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Cultured and isolated cells 8.6.13 Intact tissues and organs... 

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. 

Loosening Agents of Tight Junctions and the Time Required for Each of Them to Deplete Transmural TER as Analyzed in Cell Cultures and Isolated Epithelial Tissues... 

Compression testing by micromanipulation has been used to investigate the mechanical properties of tomato cells, both from suspension cultures and isolated single fruit cells. 

There has been much work conducted recently in the area of plant cell culture, or phytoproduction, especially where the product is a plant-unique mixture of Individual flavor substances such as vanilla extract of which vanillin is the major component. As well, the possibility of genetically engineering improved varieties of plants for high yield and consistent quality products is of considerable interest especially for more complex plant-unique flavors. Many flavor compounds are secondary metabolites for which a detailed understanding of their production is not well understood. Presently more knowledge exists In microbial metabolism relative to plant biosynthetic pathways and therefore has resulted in more successful development of microbial-based flavor bioprocessing. As well, scale-up of microbial cultures and isolated enzymes has become relatively common practice while the translation of plant cell culture to large commercial scales is not yet well established. This review will focus on the microbial whole cell and isolated enzyme systems for flavor production. 

Pharmaceutical colloids such as emulsions and suspensions (Fig. 7.1) and aerosols are readily identified (Table 7.1). The disperse phase is the phase that is subdivided. The continuous phase is the phase in which the disperse phase is distributed. Many natural systems such as suspensions of microorganisms, blood, and isolated cells in culture, are also colloidal dispersions. Colloid science is interdisciplinary, for although dealing with complex systems it is nevertheless a unifying discipline as it bridges the physical and... 

Recent advances in cell and tissue culture techniques provide the potential for evaluation of drug transport or metabolism processes at the placenta. Techniques are available for culturing trophoblasts of both animal and human origin.106 However, our focus here is primarily on human systems. Primary explant and isolated cell cultures of human cytotrophoblasts have been well described 106-109 however, these systems do not form confluent monolayer systems adequate for transcellular transport studies.105... 

Apart from the asymmetric metal catalysis, enantioselective Baeyer-Villiger oxidations mediated by enzymes have been known for some time [32,33,34]. Both whole-cell cultures and isolated enzymes, usually flavin-dependent monooxygenases, can be used to oxidize ketones enantioselectively. For future improvements in the asymmetric Baeyer-VilHger oxidation the use of chiral Lewis acids in combination with an appropriate oxidant seems worthy of intensive investigation. 

Resveratrol oligomers have been obtained from a wide variety of plants (Table (1)). These compounds have been isolated primarily from the roots, wood, and bark however, they have occasionally been extracted from the seeds, fruits, and leaves of some species. In addition, a resveratrol oligomer has been obtained from a plant cell culture. Other resveratrol oligomers have also been obtained following the incubation of 1 with fungal cultures and isolated enzyme systems. 

Interactions among cells are important for tissue development and function. The temporal and spatial signaling between cells of different origin is part of the cascade of events that support tissue growth and development. The culture of cells outside the organism disrupts these interaaions since the process of harvesting tissue and isolating cells dismpts many of the cellcell interactions found in vivo. In vitro, the result is often a loss of cell-cell contact, reduced interaction, and impaired cellular activity. 

Potential in vitro models for studying mechanisms of toxicity or screening of drugs in human kidneys are generally similar to those used in laboratory animals such as rodents or rabbits. These include the isolated perfused kidney, renal slices, isolated perfused tubules or tubules/tubular fragments, suspensions of freshly isolated cells, primary cell cultures, and immortalized renal cell culture lines. Although all of the models are theoretically possible, the most commonly used in vitro models are primary cell cultures and immortalized cell lines, allhough the latter is more common than the former. 

By culturing specific cells from cloned embryos, scientists can make embryonic stem cell (ESC) cultures. During mammalian development, two distinct cell populations form after the first few days of embryonic development. The trophoblast, or the flattened, outer layer of cells, will eventually form the placenta and its associated structures. The inner cell mass (IGM) is the round, inner clump of cells that develop to form the embryo proper and a few structures associated with the placenta. If IGM cells are isolated and cultured on feeder cells, a layer of nondividing skin cells that secrete a cocktail of growth-promoting chemicals, the IGM cells will grow and spread over the surface of the culture dish. Such a culture is an embryonic stem cell culture, and these cells are pluripotent, which means that they can differentiate into any cell type in the adult body. 

Table 2.14. Antimutagenic effects of culture liquid and isolated cells of different propionic acid bacteria...

Isolation of particular cell types that produce renal-specific factors may be a good approach for selective cell therapies to treat aspects of renal failure. For example, cells that produce erythropoietin have been isolated in culture, and these cells could eventually be used to treat the anemia that results from end-stage renal failure (Aboushwareb et al. 2008). Other more ambitious approaches are working towards the goal of total renal functional replacement. To create kidney tissue that would deliver full renal function, a culture containing all of the cell types comprising functional nephron units should be used. Optimal culture conditions to nurture renal cells have been extensively studied and cells grown under these conditions have been reported to maintain their cellular characteristics (Lanza et al. 2002). 

The bacterial CAT enzyme catalyzes the transfer of acetyl groups to chloramphenicol from acetyl coenzyme A (acetyl CoA). In a typical assay, this reaction is monitored with relabeled chloramphenicol After separation by thin-layer chromatography (TLC), the acetylated and nonacetylated forms can be distinguished by autoradiography, and quantitation is achieved by isolating the forms and measuring their radioactivity in a scintillation counter. Quantitative CAT assays have been performed on Drosophila tissue culture and dissociated cell extracts (Di Nocera and Dawid 1983 Benyajati and Dray 1984 Thummel et al. 1988 Krasnow et al. 1989 Ye et al. 1997). CAT can also be detected with commercially available antibodies. In addition, a nonradioactive CAT assay exists that utilizes a fluorescent chloramphenicol derivative (Molecular Probes). 

Robert, J., Freysz, L., Sensenbrenner, M., Mandel, P., and Rebel, G., 1975, Gangliosides of glial cells. A comparative study of normal astroblasts in tissue culture and glial cells isolated on sucrose-ficoll gradients, FEBS Lett. 50 144. 

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