Cells cytoplasm elements 132

Transmission electron microscopy energy dispersive X-ray analysis has also been used to image intracellular Se granules present from Se bioreduction in bacteria. Reduction of selenite and the deposition of elemental Se in cell cytoplasm or in the extracellular space may be lead to promising bioremediation schemes.172... 

Potential immunologic mechanisms include both autoimmune and nonautoimmune phenomena. Autoimmunity may be directed against mucosal epithelial cells or against neutrophil cytoplasmic elements. Some patients with IBD have abnormal structural features for colonic epithelial cells even in the absence of active disease. Autoantibodies to these structures have been reported. Also, antineutrophil cytoplasmic antibodies are found in a high percentage of patients with ulcerative colitis (70%) and much less frequently with Crohn s disease. Presence of antineutrophil cytoplasmic antibodies in left-sided ulcerative colitis is associated with resistance to medical therapy. Dysregulation of cytokines is a component of IBD. Specifically, Thi cytokine activity (which enhances cell-mediated immunity and suppresses humoral immunity) is excessive with Crohn s disease, whereas Th2 cytokine activity (which inhibits cell-mediated immunity and enhances humoral immunity) is excessive with ulcerative colitis. The result is that patients have inappropriate T-cell responses to antigens from their own intestinal microflora. Expression of interferon-y (a Thi cytokine) in intestinal mucosa of diseased patients is increased, while interleukin-4 (a Th2 cytokine) is reduced. ... 

A cell containing the cytoplasmic elements of two strains but the nucleus of only one of them. 

All bacteria multiply by binary division (Figure 4.1). A cell gives two completely identical daughter cells. Multiplication supposes, on the one hand, division of nuclear material, and on the other hand, synthesis for the construction of new cellular envelopes and cytoplasmic elements, in particular ribosomes and enzymes. 

The activation period - when intercellular interactions occur. These interactions are accompanied by the interchanging of biologically active macromolecules that penetrate into the cells of the reacting system and interact with cytoplasmic elements. Transcription, apparently, does not change during this period. 

The cytoskeleton is a network of different biological filaments that crisscross the cell cytoplasm. These filaments form part of different cellular structures as they associate with each other and other related proteins. Different elements of the cytoskeleton have a variety of specialized roles in cell motility, transport, and division—without a cytoskeleton, cells would not be able to function. There are three main types of filament associated with the cytoskeleton filamentous actin (F-actin), microtubules, and intermediate filaments. Each of these filament types performs different functions within the cellular machinery and as a result have very different mechanical properties. 

Ferritin, an iron-binding protein, prevents ionized iron (Fe ) from reaching toxic levels within cells. Elemental iron stimulates ferritin synthesis by causing the release of a cytoplasmic protein that binds to a specific region in the 5 nontranslated region of ferritin mRNA. Disruption of this protein-mRNA interaction activates ferritin mRNA and results in its translation. This mechanism provides for rapid control of the synthesis of a protein that sequesters Fe +, a potentially toxic molecule. 

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