Density Of Microvilli Research Articles

Surface defects in ventricular cells of brains of mouse embryos homozygous for the Loop-tail gene: scanning electron microscopic study.

Luminal surfaces in the mesencephalon and rhombencephalon in normal mouse embryos and those homozygous for Lopp-tail were studied by means of scanning electron microscopy. Ventricular cells in the ventrolateral regions of normal day-10 and -11 brains showed single apical cilia and microvilli, whereas those in ventromedial regions showed a dense network of microvilli and bulbous projections which tended to obscure the apical cilia and cellular outlines. Similar regional differences occurred in the Loop-tail brains, although there was a marked decrease in the number and density of microvilli and bulbous projections. At days 12-14 of gestation the latter brains also showed a flattening of cell surfaces, shallow depressions, and craterlike ruptures in the plasma membranes.

The densities of colloidal iron hydroxide particles bound to microvilli and the spaces between them: studies on glutaraldehyde-fixed Ehrlich ascites tumour cells.

ABSTRACT The densities of positively charged, colloidal iron hydroxide particles binding to the surfaces of glutaraldehyde-fixed cultured Ehrlich ascites tumour cells, were determined on cells maintained in suspension and monolayer cultures. In both cases, there was a higher density of particles bound to the surfaces of microvilli than to the spaces between them. Prior treatment of the cells with ribonuclease did not significantly alter the proportions of particles binding to the 2 different surface regions, indicating that the ribonuclease-susceptible binding sites are distributed with similar mean densities over the microvilli and the regions between them. Prior treatment of the cells with neuraminidase reduced the densities of particles binding to microvilli to those of the intermicrovillous spaces, indicating that the original higher density over the microvilli is due to an increased number of sialic acid residues at their surfaces. The findings are discussed in relationship to observed changes in the surface density of microvilli when these cells convert from suspension to monolayer cultures.

Electron Microscopic Survey of the Presence of Microvilli on Cultured Mammalian Cells<xref ref-type="fn" rid="FN2">2</xref>

Electron microscopic examination of the surface of a variety of cultured mammalian cells revealed that some cell strains have a density of microvilli greater than 10 per 100 μ2, whereas others have less than 2 per 100 μ2. The only correlation found between these two classes of cells is that those with the high density of microvilli were established in culture earlier than those almost devoid of microvilli.

976. One more advance in tartrazine metabolism: Jones, R., Ryan, A. J. & Wright, S. E. (1964). The metabolism and excretion of tartrazine in the rat, rabbit and man. Fd Cosmet. Toxicol.2, 447. Westöö, G. (1965). On the metabolism of tartrazine in the rat. Acta chem. scand.19, 1309

Food dyes, or color additives, are often added into foods, cosmetics and beverages during processing to improve the sensory attributes of the final products. However, the toxicity of tartrazine (TZ), one of the most common azo-dyes, is still unclear, and needs to be ascertained by further study. Hence, in the present study, we aimed to evaluate the effects of TZ consumption on health by using a teleost, crucian carp (Carassius auratus) as the experimental fish. TZ consumption (1.4, 5.5 and 10 mg/kg bwt/day) could cause severe histopathological and cellular alterations in intestine and liver. The height of intestinal villus, thickness of intestinal muscle, and microvilli density were also affected. With the increasing of TZ concentrations, the activities of antioxidant enzymes (CAT, SOD and GSH-Px), exhibited a decreasing trend, while the contents of MDA elevated. Upregulations of pro-inflammatory cytokines (il6 and tnfα), anti-inflammatory cytokines (il8, and il10) and other immune related genes (complement component 3 (c3), lysozymes (lyz), β-defensin 3 (defb3)), were observed after TZ uptake. In addition, TZ consumption also affected the community structure of the microbiota in the intestine of crucian carp. The amount of some probiotic bacteria (Roseomonas, Rhodococcus and Bacillus) and the bacteria (Bacteroides and Clostridium), producing short chain fatty acids, were significantly reduced, and some pathogenetic microorganisms (e.g. Bdellovibrio and Shewanella) were significantly increased after TZ uptake. In summary, the data in the present study indicate that TZ consumption, even at a low concentration, may lead to adverse effects on fish health. Therefore, in aquaculture, it is necessary to be informed about the hazardous effects of TZ, and more attentions should be focused on using natural substitutes.