Nuclear/cytoplasmic ratio

Gautier Returning to the nuclear cytoplasmic ratio, in a situation where you don t block any event in the cell cycle, such as experiments in frogs where a mosaic is made between the diploid and tetraploid tissue, the tetraploid cells are twice as large. There is some regulation here the amount of DNA is somehow influencing the size of the cell. 

Mailer You need a nuclear cytoplasmic ratio that can send an adequate signal to be heard. I would speculate that the signal is sent, even when there is only one nucleus, but it may not be heard by the cell cycle or apoptotic machinery that is present in great abundance. 

Stratum basale is a single layer composed of stem cells and their derivative cells. It is attached to the basement membrane by hemidesmo-somes.48 The cells in this layer are columnar or cuboidal in shape and characterized by large nuclei (high nuclear-cytoplasmic ratio) and keratin filaments (tonofilaments). The basal layer contains keratins K14 and K15, melanocytes (which are pigment-forming cells), Langerhans... 

Cell size, plastochron 16 154 N uclear-cytoplasmic ratio, 0.70-plastochron 6 Nuclear-cytoplasmic ratio, plastochron 16 Percent mitotic divisions, plastochron 6 (includes chiefly prophase and telophase stages)... 

While all the aforementioned cell types form the epithelial surface of the airways, basal cells reside deep in the tracheo-bronchial epithelium and are not directly in contact with the airway lumen. Basal cells are considered as the stem cell or progenitor cell of the bronchial epithelium and are pyramidal in shape with a low cytoplasmic/nuclear volume ratio [8, 15-17],... 

Morphology Lymphocytes possess a large nucleus with little to no basophilic cytoplasm. Differences are seen in the nuclear (N) to cytoplasmic ratio, the degree of cytoplasmic staining with histological dyes and the presence or absence of azurophilic granules. 

The drawback of this approach is that it cannot discriminate between mitotic and apoptotic cells. Early G (postmitotic) cells also have high fluorescence intensity of the maximal pixel (17). The distinction between apoptotic and mitotic cells is critical after treatment with agents such as taxol or other mitotic blockers, i.e., when mitotic cells undergo apoptosis. The visual examination of the cells, or analysis of other morphometric features such as nucleus to cytoplasm ratio, nuclear or cellular area or circumference, forward light scatter, and so on, as offered by LSC, however, can be helpful in these instances. 

Cytologically, the cells of BSCC are round to oval and have hyperchromatic nuclei with a high nuclear-to-cytoplasmic ratio. The nuclei may demonstrate peripheral palisading around the lobules. There are often prominent mitoses and apoptotic bodies in the basaloid component.The conventional SCC component can be invasive or in situ, and it can be found in separate foci or merge with the basaloid component. 

A low nuclear to cytoplasmic ratio, polygonalshaped cells, finely granular eosinophilic cytoplasm with an eosinophilic hue, coarse nuclear chromatin, and frequent nucleoli... 

Metanephric adenoma of the kidney is a unique form of renal adenoma characterized by a proliferation of tubular and micropapillary to glomeruloid structures lined by bland cuboidal epithelial cells. The relatively high nuclear-to-cytoplasmic ratio of metanephric adenoma cells and their slightly amphophilic cytoplasmic coloration impart a typical blue low-power appearance to the neoplastic nodule. The latter is in contrast to the lighter eosinophilic appearance of its main differential diagnosis entity, namely the solid variant of papillary Like papillary RCC, metanephric adenoma can feature foamy histiocytes in papillary cores and occasional psammomatous calcifications. Helpful... 

Anti-GFAP immunostain (Fig. 20.2) highlights the dark-brown intense immunoreactivity, relatively low nuclear to cytoplasmic ratio, and the separation of... 

Perivascular inflammation consists of small round cells with high nuclear to cytoplasmic ratios. These can be mistaken for lymphoma and for neuroectodermal clusters, which are particularly common in brains of children. Leukocyte common antigen (LCA CD45/45R), CD3 epsilon, CD5, CD20, and CD79 alpha markers distinguish the inflammation by highlighting polyclonal reactive lymphocytes (see Fig. 20.3B and C). 

FIGURE 20.17 Pleomorphic xanthoastrocytoma. Round lipid vacuoles are visible in pleomorphic astrocytes with H E in this particular specimen. Note that nuclear to cytoplasmic ratios are low, chromatin is finely granular, and nuclear membranes have gentle curves despite the large pleomorphic nuclei and nucleoli. 

Nuclear crowding and high nuclear to cytoplasmic ratio impart a distinctly blue macroscopic appearance... 

Many monkeys had a mild, erosive enterocolitis, with slight multifocal, superficial mucosal loss, and with numerous lamina proprial macrophages bearing engulfed cellular debris. Crypt enterocytes had a high nuclear-to-cytoplasmic ratio and numerous mitoses. The crypt epi-... 

Cells were cultured in a humidified ahnospheric incubator at 37°C in 5% CO2. Human promyelocytic leukemia cell line (HL-60) was cultured in RPMI 1640 supplemented with 13% heat-inactivated fetal bovine serum and SO U/mL penicillin-streptomycin. To induced myeloid differentiation, cells were seeded at a density of S IO cells/mL and were cultivated for five days in RPMI 1640 containing 1.24% DMSO. TTie characteristics of mature cells were determined by smaller cell size, decreased nucleoli-to-cytoplasm ratio and pyknotic changes in nuclear chromatin. Cell numbers were counted using a hemocytometer, and cell viability was >98% as evidenced by trypan blue staining. 

Hunt In the human body, for example, what is the normal range of nuclear to cytoplasmic volume ratios ... 

Nasmyth There is a similar situation in Drosophila, where you also have a high cytoplasminucleus ratio. The only problem in Nenopus is that the whole cell cycle clock is occurring throughout the entire cytoplasm, whereas Drosophila has a certain degree of nuclear autonomy. Even there, these controls are missing to some extent. 

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