Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Rhodamines”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 recordsLinked to original sources
PubMed1979

Mutagenic activity of rhodamine dyes and their impurities as detected by mutation induction in Salmonella and DNA damage in Chinese hamster ovary cells.

Commercial rhodamine dyes 6G and B induce His+ reversion mutations in Salmonella and single-strand breaks in Chinese hamster ovary cells, as detected by alkaline sucrose sedimentation. Aroclor 1254-induced rat liver homogenate (S9) is required for production of genetic activity by these dyes. Rhodamine 6G induces both frameshift and base substitution mutations, whereas rhodamine B induces only frameshift mutations. Rhodamine 6G is genetically more active and more toxic than is rhodamine B in both the bacterial and mammalian assays. Rhodamine 6G and B induce doublings of His+ revertants in Salmonella at the doses of 0.02 and 0.52 mumol/plate and shifts in the molecular weight of Chinese hamster ovary DNA at concentrations of 9 x 10(-5) and 9 x 10(-4) M, respectively. All genetic effects assayed demonstrate dose-related increases. Further testing of the pure dyes in Salmonella revealed that rhodamine B loses most of its mutagenicity with purification, whereas rhodamine 6G does not. Impurities from commercial rhodamine B demonstrate the same extent of mutagenicity as the commercial dye.

Animals↗
PubMed1976

The reliability of gastric smears by auramine-rhodamine staining technique for the diagnosis of tuberculosis.

From 1972 to 1974, all sputum specimens and gastric aspirate specimens submitted to the University of Michigan Laboratory for acid-fast smear and culture were studied. Specimens were paired for culture and smear results using the auramine-rhodamine staining technique. Of 1,893 patients, 75 patients without prior antituberculous therapy were found to have either a positive smear or a positive culture of either sputum or gastric material. The data analyzed by patient source revealed the following. (1) Staining sputum with auramine-rhodamine is a clinically reliable technique for detecting pulmonary tuberculosis. It demonstrates a sensitivity of 78 per cent and a relative fraction of false positive smears of only 11 per cent. (2) Staining gastric-aspirated material by the auramine-rhodamine technique is not a clinically reliable method as a routine procedure for the detection of pulmonary tuberculosis, because of a sensitivity of only 58.8 per cent and a relative fraction of false-positive smears of 33 per cent. (3) In the absence of sputum in suspected clinical granulomatous disease, quantified gastric smears may be helpful. In this study, when more than 6 organisms per high power field were found, the patient's sputum or gastric material yielded a pathogenic mycobacterium on culture.

Aniline Compounds↗
PubMed1977

Extra-chromosomal inheritance of rhodamine 6G resistance in Saccharomyces cerevisiae.

Rhodamine 6G was found to be a specific inhibitor of aerobic growth of yeast, having no effect on fermentative growth. A single step spontaneous mutant of S. cerevisiae resistant to rhodamine 6G was isolated, which showed cross-resistance to the ATPase inhibitors venturicidin and triethyltin, to the uncoupler 1799, to bongkrekic acid and to cycloheximide, but not to oligomycin or to the inhibitors of mito chondrial protein synthesis, chloramphenicol and erythromycin. The genetic analysis of this mutant showed that both nuclear and cytoplasmic (but apparently not mitochondrial) factors may be involved in the determination of the mutation. The behaviour is discussed as a possible function for 2 micron circular (omicron) DNA.

Cross Reactions↗
PubMed1978

Rhodamine immunohistofluorescence applied to plant tissue.

Tissue slices from the roots and seeds of sanifoin (Onobrychis viciifolia, Scop.) exhibit bright autofluorescence when illuminated with blue (495 nm) light. This autofluorescence is indistinguishable from the fluorescence emission of fluorescein, the commonly used fluorochrome in immunohistochemical staining procedures. Rhodamine isothiocyanate, when coupled to immunoglobulin, and excited with green light at 546 nm, exhibits a reddish-orange fluorescence with an emission maximum at 590 nm. Plant tissue has little or no autofluorescence when illuminated at this wavelength and viewed with a 580 nm barrier filter. Therefore, use of rhodamine for immunohistochemical localization in plant tissue avoids interpretative complications due to inherent autofluorescence.

Antigens↗
PubMed1978

[Limited diffusion of dye between choroid and retina during animal experiments after injection of fluorescein and rhodamin (author's transl)].

For contributing to the question of an existence of a diffusion of the unbound part of the fluorescein between choroid and retina in fluorescein angiography, on pigmented rats, after intravenous injection of Fluorescein sodium and Rhodamine B respectively, comparing observations were effectuated. Rhodamine B in its unbound form showed a distinct diffusion between choroid and retina and coloured all retinal layers in the late phases whereas in the case of the Fluorescein sodium, only a poor diffusion was observable. The similar spectral bands of the primary and secondary fluorescences render difficult the observation of the behaviour of the fluorescein dye.

Animals↗
PubMed1979

Comparison of auramine-rhodamine B and acridine orange for staining of acid-fast bacteria.

In cooperation of 6 laboratories in Czechoslovakia and in the GDR, the efficiency of auramine-rhodamine B (AR) and acridine orange (AO) (short-time method) for staining of acid-fast bacilli was compared. Whereas a former comparison of AR and AO (original method) pointed out the superiority of AR, the investigation of both methods used as short-time procedures showed significantly more acid-fast rods after using AO. The number of "false positive" results was somewhat higher on AR staining. However the results depend not only on the method used but also on the procedure of staining and the optical equipment, and they are essentially influenced by the experience and proficiency of the microscopist. Taking into account the results of both studies both auramine-rhodamine B and acridine orange can be proposed for the staining of slides for microscopical detection of acid-fast rods. In case of AO, the short-time method is superior to the original long-time procedure.

Acridine Orange↗
PubMed1978

The use of rhodamine-latex particles in B-cell determinations.

A simple, inexpensive, and easily visible procedure for labeling phagocytic cells in B-cell preparations is discussed. The procedure involves adding rhodamine-latex particles to lymphocyte preparations, then simultaneously looking for the presence of ingested latex particles in contaminating phagocytic cells and for fluorescein labeled surface immunoglobulins. This differentiation of cells allows one to correct for the true percentage of B cells.

Adolescent↗
PubMed1975

Rhodamine conjugates:specific and nonspecific binding properties in immunohistochemistry.

Anionic-exchange fractions of IgG labeled with FITC, MRITC, RB200SC, or RBITC were tested on different substrates, and the resultant fluorescence was evaluated with the Ploem optical system. Conjugations with MRITC or RB200SC were found to afford the following advantages over FITC: immunofluorescence sensitivity was elevated six to seven times on a molar basis; high sensitivity could be combined with a wide specificity interval; there was negligible fading of emitted light; there was negligible tissue autofluorescence at the excitation wavelength (546 nm); because of the two latter points, repeated observations could be made on tissue sections stored for several years; and eosinophilic leukocytes that are prone to yield nonspecific staining could easily by identified by switching to ultraviolet-blue light excitation.

Animals↗
PubMed1975

An approach to quantitation in rhodamine isothiocyanate labeling.

A survey of commercially available TMRI and RBI products revealed that many are of unsatisfactory quality. Optimum dye/IgG ratios were obtained in conjugates with TMRI of about 65% purity by labeling them with reaction mixture ratios of 10 and 20 mug dye/mg IgG. Optimum labeling with RBI of comparable purity required reaction mixture ratios of at least 20 mug dye/mg IgG. Although specific storage stability studies of TMRI or RBI products were not performed, one TMRI product underwent appreciable degradation during a 2-year period of storage in a desiccator over Drierite. The importance of evaluating the protein labeling capacity of TMRI or RBI products before making immune conjugate preparations is evident.

Animals↗
PubMed1979

Rhodamine as a fluorescent probe of lymphocyte activation.

Fresh rat and mouse lymphoid cells have been labelled by stable linkage with tetramethylrhodamine isothiocyanate (TMRITC). A change in intensity, either an increase or decrease of the fluorescent emission of the cells, detected by microfluorimetry, was induced by mitogen stimulation or the mixed lymphocyte reaction. The change in fluorescence was observed within 3 h of mitogen stimulation and within 0.5 h in the mixed lymphocyte test. These early cellular responses were detectable consistently whether the labelling was done before or after mitogen stimulation; post-labelling only was studied in the mixed lymphocyte reaction. The method should provide a time-saving practical procedure for early detection of the lymphoid cell responses and would readily lend itself to flow cytofluorimetry for possible routine diagnostic use.

Animals↗