Extracellular accumulation

Extracellular Accumulation (jngdJ) TirtB after elicitation (d) Conirol PEF Stimulating activity ... 

Targeted extracellular recombinant production generally results in low-level extracellular accumulation of the desired protein (often in the milligram per litre range). Extracellular production simplifies subsequent downstream processing, as discussed later in this chapter. 

The resistance of many human cancers to immunotherapies has been attributed to the presence of immunosuppressive molecules located in tumor areas. Adenosine is present at elevated levels in hypoxic tissues due to an increased intracellular production and extracellular accumulation, as described above. This nucleoside activates cell surface receptors on T and NK cells that mediate cellular immune responses to tumor cells. It is well established that T cells recognize and destroy... 

Stein-Behrens B. A., Elliott E. M., Miller C. A., Schilling J. W., Newcombe R., and Sapolsky R. M. (1992). Glucocorticoids exacerbate kainic acid-induced extracellular accumulation of excitatory amino acids in the rat hippocampus. J. Neurochem. 58 1730-1735. 

Extracellular accumulation of Af) represents the foundation of the amyloid cascade hypothesis. The importance of intracellular A accumulation in the pathogenesis of AD has emerged as a possibility in recent studies (LaFerla et al., 2007). These studies, implemented in human and mouse brains were made possible by the development of antibodies that could differentiate A O and Af)42 from the transmembrane amyloid precursor protein from which they derived (Gouras et al.,... 

Moghaddam B, Bohnao ML, Stein-Behrens B, Sapolsky R (1994) Glucocorticoids mediate the stress-induced extracellular accumulation of glutamate. Brain Res 655 251-254. 

Disturbance of the intracellular calcium homeostasis is involved in the pathogenesis of neurodegeneration and probably in the extracellular accumulation of Ap. Calcium channel blockade attenuates Ap-induced neuronal damage. Several calcium channel blockers have been tested in dementia with poor results. In some clinical trials, nimodipine and nilvadipine showed some positive results on cognition, whereas other calcium channel blockers failed [515]. 

Although there is some controversy as to whether the glutamate levels in the nervous system actually increase after ischemia (Zeevalk and Nicklas, 1990), most studies confirm that cerebral ischemia (Drejer et al., 1985) and hypoglycemia (Burke and Nadler, 1989) cause endogenous release and extracellular accumulation of glutamate. 

Retinal ischemic injury, for example, has been shown to result in the overstimulation of ionotropic glutamate receptors following the extracellular accumulation of glutamate (18,19). This effect appears to involve, in particular, the NMDA class of glutamate receptors. The subsequent excessive influx of calcium results in... 

In this chapter, we shall discuss the distribution of ions among the extracellular phases. Extracellular accumulation is interesting and important in its own right, as it influences the value and safety of food crops, and induces or alleviates the intoxicating effect of ions whose site of action may lie in the apoplast (Horst, 1995). Extracellular accumulation of ions in the root also determines the intracellular accumulation and translocation of ions to the rest of the plant. The following diagram illustrates our conceptualization of ion interactions among phases of the rhizosphere and the plants. 

The metabolism of the terpene alcohols into 3-D-glucoside has been well documented. The peppermint cells, especially, are known to possess a high glucosyl transferase activity [9]. This work clearly demonstrates the accumulation of the glucosides in the cell rejecting the implied extracellular accumulation [12]. 

Schini, V., Grant, N. J., Miller, R. C., and Takeda, K. (1989) Morphological characterization of cultured bovine aortic endothelial cells and the effects of atriopeptin II and sodium nitropmsside on cellular and extracellular accumulation of cyclic GMP Euk j. Cell Biol. 47,53-61. 

Fig 1. Extracellular accumulation of acyl-camitmes m hepatocytes isolated from neonatal rats. 

T. (1972) L-Glutamate fermentation with acetic acid by an oleic acid requiring mutant. II. Inhibitory factors against the extracellular accumulation of L-glutamate. J. Ferment Technol, 50, 182-191. 

The extracellular accumulation of alginate acts as a barrier to oxygen diffusion or heavy metals or as protection against other environmental insults [8]. 

The extracellular accumulation of Ap in microglia cells occurs in the course of AD these cells are the primary immune effector cells with the ability of phagocytosis in the CNS. Apl 2 activates the formation of plaques, Apl O is stored in them simultaneously or with a delay. 

Oligogalacturonides have also been used to produce trans-R in grapevine cells cv Gamay [45]. In fact, 2 mg oligogalacturOTiides g FW induced an extracellular accumulation of 20 pg trans-R g FW after 12 h of treatment, and similar trans-R... 

DW) than 10 pM Ja (around 4.5 pg g DW), although both elicitors promoted its release into the extracellular medium in V. vinifera cv Barbera cell cultures (around 8 pg trans-R DW after 2 days of elicitation). In the same way, Santamaria et al. [42] also investigated the abDity of Ja (20 pM) and MeJa (20 pM) to increase the production of trans-R in V. vinifera cv Italia cell cultures. They detected a peak of trans-R inside cells (55 and 84 pg g DW using Ja and MeJa, respectively) after 20 days of culture. In this case, Ja was most effective in inducing the release of trans-R into the medium (1.55 mg L ) than MeJa (0.27 mg L ). Belhadj et al. [30] working with V. vinifera cv Camay Freaux cell cultures elicited with 20 pM MeJa detected an extracellular accumulation of 11.87 pg trans-R g FW after 18 h of treatment. Belchi-Navarro et al. [59] observed that the addition of 25 pM MeJa provoked an enhancement of trans-R in the culture medium of 1.02 mg g DW (i.e., 51 pg g FW) in V. vinifera cv Monastrell cell cultures. Moreover, these authors showed that in the presence of 50 or 100 pM MeJa, the trans-R levels increased to reach values of 3.74 mg g DW (i.e., 187 pg g FW). 

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