Vital stains

Vitalf bung, /. vital staining, intra- iiam staining. 

Others Molecular probes— stain all, vital stain Vital stains particularly useful for total viable cell counts 122... 

Respiration systems INT, CTC (tetrazo-lium compounds) Vital stains 116, 125... 

A solution of buffered methylene blue (pH 3.6) may be used as a vital stain for the examination of fresh specimens for protozoa. The wet mount is prepared as described above, with buffered methylene blue substituted as diluent and 5 to 10 min allowed for the dye to become incorporated in the organisms before examination. Organisms become overstained in 20 to 30 min. 

Imbert D, Cullander C (1999) Buccal mucosa in vitro experiments I. Confocal imaging of vital staining and MTT assays for the determination of tissue viability. J Control Release 58 39-50... 

Reticulocyte. A young red blood cell showing a basophilic reticulum under vital staining. 

Fig. 1 Epifluorescence micrograph of Piromyces sp. E2 originally isolated from the faeces of an Indian elephant. Magnification about x400. The organism was vitally stained with rhodamine 123. S young sporangia...

Matsuda, R., Nishikawa, A., and Tanaka, H., 1995, Visualization of dystrophic muscle fibers in mdx mouse by vital staining with Evans blue evidence of apoptosis in dystrophin-deficient muscle, J Biochem (Tokyo), 118, pp 959-964. 

The discovery of Zanamivir as a potent and selective inhibitor of influenza virus sialidase prompted several researchers to investigate the synthesis and structure-activity relationship studies of Neu5Ac2en-based compounds as potential sialidase inhibitors. Exploration of these SAR studies were undertaken to optimize inhibitory activity and to improve the physicochemical properties of the sialic acid-based influenza virus sialidase inhibitor. A few in vitro assays are commonly employed to measure the effectiveness of influenza virus sialidase inhibitors. The first involves a fluorometric assay that measures release of a synthetic fluorophore following its cleavage from Neu5Ac by sialidase. Dye-uptake assay, such as the Neutral Red uptake assay, measures the uptake of a vital stain, Neutral Red in cell culture. The process requires intact membranes and active metabolism in the cell, and is expressed as percent protective rate against virus infection. The plaque-reduction assay is used to measure sialidase inhibition indirectly in cell culture, and provides some measure of the inhibitor s effect on the viability of the influenza virus. In vitro and in vivo systems for analysis of inhibitors of influenza virus enzymes have been reviewed.71... 

Figure 5. Dark-field fluorescence photomicrograph of 3T3 murine fibroblasts vitally stained with acridine orange a) treated with W. floribunda agglutinin (75 Hg/ml) in Eagle s Minimum Essential Medium with Hanks salts for 48 hr b)...

Other vital stains take advantage of different cellular properties which can be correlated with cellular physiology Propidium Iodide, Ethidium Bromide, Ethidium Monoazide, Calcofluor White have been widely used to indicate the presence of dead eukaryotes or prokaryotes cells. 2-(p-iodophenyl-)3)(p-nitro-phenyl)-5-phenyl tetrazolium chloride (INT) belongs to a class of stains which can be used to determine if a cell or hyphal compartments [180] can maintain an internal reducing environment (Fig. 20a). There are, however, still a large debate about the reliability of those techniques, depending upon the cells under consideration [181]. Calcofluor (Aex = 380 nm, Aem 420 nm) is a specific cell wall stain which enables to counts buds scars on Saccharomyces cerevisiae [29] to estimate the age of a cell. 

Compound (13) and the derivatives (127)—(129) have been useful as a vital stain to serve as a physiological probe for specific neurotransmitter pools. Inhibition of the binding of radiolabeled serotonin, choline, y-aminobutyric acid, noradrenaline, and dopamine was observed <9lMiP9ii4l84>. 

Another and more convincing explanation for this discrepancy of previous and recent studies related to the inactivation of Cryptosporidium refers to the methods of viability testing. So, it seems that in vitro viability assays (chemical excystation and vital stains) that have been used previously may have significantly underestimated the inactivation efficacy of UV-C irradiation of the parasites compared with in vivo infectivity assays applied in recent studies using neonatal mouse models (Craik et al, 2001). This was also demonstrated by UV inactivation of Giardia muris cysts using MP Hg lamps (Craik et al., 2000). 

Lissamine green is a vital stain that stains degenerate cells, dead cells, and mucus in much the same way as rose bengal. It is also widely used in the food industry as a colorant. 

Methylene blue, a vital stain (Urolene blue), has properties similar to those of rose bengal. It can stain both devitalized cells and mucus and corneal nerves. It is not a specific stain when applied to the eye because the blue areas may be either cells or mucus. Clinically, methylene blue is useful for staining the lacrimal sac before dacryocystorhinostomy and outlining glaucoma filtering blebs, and it may prove useful in gonioscopic laser sclerostomy. More recently it has been used in vitro (tissue extraction and absorbance at 660 nm) to examine the effects of... 

Vital staining of corneal nerves requires up to three instillations at 5-minute interrals.The bluish ocular discoloration may remain fc>r 24 hours. 

Norn M. Fluorexon vital staining of cornea and conjunctiva. Acta Ophthalmol 1973 51 670-678. 

Norn MS. Vital staining of the cornea and conjunctiva. Acta Ophthalmol 1962 40 389-401. 

Norn MS. Rose bengal vital staining. Staining of cornea and conjunctiva by 10 percent rose bengal, compared with 1 percent. Acta Ophthalmol 1970 48 546-559. 

Norn MS. Lissamine green. Vital staining of cornea and conjunc-tiva.Acta Ophthalmol 1973 51 483-491. 

The occurrence of vanadium in the lower oxidation states, which as the simple aqua ions undergo acid dissociation above pH 3 [if present as V(III)) ] and pH 6 [in the case of oxo-V(IV) ], along with the high sulfur content of ascidian blood and the low pH that results when ascidian blood cells are ruptured in distilled water has led to the belief that intact vanadium-containing tunicate blood cells are acidic (145). Other lines of evidence, including vital staining and NMR (144,170), and... 

To measure performance, to achieve reproducibility or to make comparative studies, a means of quantifying the cell population is needed. Classically, direct counts of cell numbers using a microscopic counting chamber (haemocytometer), usually in conjunction with a vital stain (e.g. Trypan blue) to distinguish viable and non-viable cells, is used. However, all vital stains are subjective and cannot give absolute values, and cell numbers take no account of differences in cell size/mass. The method is simple, quick and cheap, and requires only a small fraction of the total cells from a cell suspension. 

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