Cells apoptotic

In apoptotic cell death, several factors such as growth factors, NO, the tumor suppressor gene p53, and the protein encoded by this gene contribute to the process that leads to cell death. One of the functions of p53 protein is the activation of apoptosis if a cell is transformed to a malignant cell. Apoptosis typically leads to the formation of smaller membrane-encapsulated particles within the cell. Apoptotic cell death begins in the nucleus and proceeds to other parts of the cell. The death process may be quite advanced before it can... 

Phagocytes are a group of cells that may engulf and internalise antigens, pathogens or apoptotic cells and destroy them. 

TUNEL is the name given to the in-situ DNA endlabelling technique which serves as a marker of apoptotic cells. This method is based on the specific binding of terminal de-oxy nucleotidyl transferases to the 3-hydroxy ends of DNA. The technique is normally used for examination under the light microscope but can also be adapted for examination under the electron microscope. 

One of the early events of the apoptotic process involves the translocation of phosphatidylserine on the surface of cell membranes annexin V binding and propidium iodide uptake reveals various cellular states. After treatment with organotin(IV) compounds the cells could be categorized into populations vital cells (annexin V /P ), early apoptotic cells (annexin V /P ), late apoptotic cells (annexin V /P ), and necrotic cells (annexin V /P" ). Cells are observed with a fluorescence microscope and it is possible to observe translocation of phosphatidylserine (PS) from the inner side of the plasma membrane to the outer one and to see a green stain for annexin V FLUOS bound to PS, and a red stain for propidium iodide. 

Raff If you starve hydra, they just shrink. Cell proliferation carries on almost normally, but cell death (apoptosis) greatly increases. The animals survive by eating their own apoptotic cells. 

Fox DA, Campbell ML, Blocker YS. 1997. Functional alterations and apoptotic cell death in the retina following developmental or adult lead exposure. Neurotoxicology 18(3) 645-664. 

Kalariya, NM, Ramana, KV, Srivastava, SK, and van Kuijk, FJ, 2008. Carotenoid derived aldehydes-induced oxidative stress causes apoptotic cell death in human retinal pigment epithelial cells. Exp Eye Res 86, 70-80. 

Doubling of apoptotic cells at 8 LI M Doubled again at 16uM. 32 LI M increased 20% more 5.5-36.7 pmol/106 cells with 3 pM the highest No difference at any concentration... 

Increase membrane dysfunction of 20% and 13% at 1 pM and 3 pM for DiOC6. Fivefold increase in apoptotic cells using JC-1 at3pM... 

Polyproteins (as exemplified by the NPAs) are not the exclusive products of apoptotic cells, so the polyprotein nature of the keratinocyte filaggrins of humans requires a new explanation. The NPAs might provide a model for repetitive-type polyproteins which could impinge on the understanding of polyproteins as a whole. 

T cell and cytokine regulation of enterocyte apoptosis may also be important in the expulsion of nematodes, in particular T. spiralis and T. muris, which inhabit an intracellular niche. Certainly an increase in the number of apoptotic cells within the epithelium is observed around the period of expulsion of T. muris in resistant mouse strains (D. Artis, C.S. Potten and R.K. Grencis, unpublished). Apoptosis of host enterocytes may dislodge the nematode or perhaps expose vital feeding organs to immune attack, and so enhance expulsion. Whether enterocyte apoptosis results from the burrowing action of the worms or a tissue repair mechanism, or is involved in expulsion, remains to be investigated. 

In spite of the heavy atom, compound (32) is sufficiently fluorescent for this to be used as an analytical tool to examine localization and pharmacokinetics. In EMT-6 murine tumors, (32) localizes initially on lysosomes, with selectivity for tumor over surrounding normal tissue, and with evidence for apoptotic cell kill.137 Fluorescence studies using a hamster cheek pouch model show a maximum emission in 2-3 h, with selectivity for the tumor (x 1.5 over normal tissue) after 24 h the photosensitizer is no longer detectable.138 Lutetium texaphyrin (32) has been compared... 

Annexin V-functionalized crosslinked iron oxide (CLIO) was designed as a contrast agent for MRI, which was additionally labeled with Cy5.5 to allow colocalization with optical imaging techniques [98]. Alternatively, conjugation of multiple Gd-DTPA molecules or SPIO particles to the C2 domain of synaptotagmin I was shown to allow the detection of apoptotic cells in vitro [99]. Zhao et al. [100] were the first to apply a C2 domain-functionalized SPIO and showed very promising results for future in vivo applications of MR contrast agents for the detection of apoptotic sites. 

Williamson, P., Schlegel, R. A. Transbilayer phospholipid movement and the clearance of apoptotic cells. Biochim. Biophys. Acta 1585 53-63, 2002. 

NO may react with superoxide to yield the highly reactive peroxynitrite, ONOO-. Superoxide may also be converted into H202 and the reactive hydroxyl radical, OH. In this way excessive activation of glutamate receptors leads to oxidative damage. The calcium influx has a major effect on mitochondria and causes them to depolarize and swell. This leads to a pore being formed in the outer mitochondrial membrane, which allows the escape of cytochrome c and procaspases from the mitochondria into the cytosol. Cytochrome c activates the caspase cascade, which leads to apoptotic cell death (Ch. 35). 

Gorczyca, W., Gong, J., and Darzynkiewicz, Z., Detection of DNA strand breaks in individual apoptotic cells by the in situ terminal deoxynucleotidyl transferase and nick... 

Darzynkiewicz, Z. et al., Features of apoptotic cells measured by flow cytometry. Cytometry, 13, 795, 1992. 

Vermes, I., Haanen, C., and Reutelingsperger, C., Flow cytometry of apoptotic cell death, J. Immunol. Methods, 243, 167, 2000. 

Vandivier, R.W., et al., Role of surfactant proteins A, D, and Clq in the clearance of apoptotic cells in vivo and in vitro Calreticulin and CD91 as a common collectin receptor complex, J. Immunol. 169, 7, 3978, 2002. 

Takahashi, M. and Kobayashi, Y., Cytokine production in association with phagocytosis of apoptotic cells by immature dendritic cells, Cell. Immunol. 226, 2, 105, 2003. 

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