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At least 19 recordsLinked to original sources
PubMed1976

Hormone binding by cells and cell fragments as visualized by fluorescence microscopy.

Fluorescent-labeled hormones offer an alternative approach to radio-labeling in studying the binding of hormones to intact cells or cell fragments. The binding of fluorescent-labeled hormones may be followed quantitatively by measurement of the polarization or the binding may be directly visualized in the fluorescence microscope. The binding of both fluorescein labeled prolactin and estradiol to a variety of whole cells or to microsomal fragments has been observed by fluorescence microscopy. No staining was observed with fresh cells whereas all cell types investigated, after freeze-thawing, stained at physiological levels (10-9M) of either hormone. Microsomal preparations from the mammary tissue of mid-pregnant rabbits likewise stained at low levels of prolactin. Inhibition of staining was not produced even by 10-6 M unlabeled hormone.

Cell Line↗
PubMed1978

Polarization and fluorescent microscopy--simple methods for demonstrating pulmonary surfactant lipids.

Birefringence and fluorochrome lipid staining with benzpyrene are demonstrated as simple morphological methods to reveal the presence or absence of surfactant lipids in human newborn lung tissue. Lack of lipid birefringence proves to be an associated finding in the lungs of premature infants with hyaline membrane disease, indicating the possible pathogenetical importance of surfactant deficiency.

Benzopyrenes↗
PubMed1979

Studies on conformational changes in F-actin of glycerinated muscle fibers during relaxation by means of polarized ultraviolet fluorescence microscopy.

By means of polarized ultraviolet fluorescence microscopy the conformational changes of F-actin occuring in glycerinated muscle fibers of rabbit and barnacle (Balanus rostratus Hock.) under the influence of adenosine triphosphate in the presence of ethylene glycol bis(beta-amino-ethyl ether)-N,N'-tetraacetic acid were discovered. These changes seem to be located near the surface of the globules thus hampering the penetration of univalent iones and neutral molecules into the F-actin macromolecule. It is suggested that similar changes of F-actin take place in thin myofilaments of living muscle fiber during the contraction-relaxation process.

Actins↗
PubMed1977

Localisation of non-replicating heterochromatin in polytene cells of Drosophila nasuta by fluorescence microscopy.

A simple fluorescence technique is decribed to localise in situ the non-replicating alpha heterochromatin in the chromocentre region of Drosophila nasuta polytene nuclei. After incorporating 5-bromodeoxyuridine in larval salivary gland cells for one or two cycles of replication, the polytene nuclei are examined for Hoechst 33258 flourescence at pH 7.0. The non-replicating alpha heterochromatin remains brightly fluorescing as it does not incorporate any 5-bromodeoxyuridine while the rest of the replicating chromatin shows dull fluorescence due to the quenching of Hoechst 33258 fluorescence by the bromodeoxyuridine substituted DNA.

Animals↗
PubMed1976

Study on development of Agaricus bisporus by fluorescent microscopy and scanning electron microscopy.

Two strains of Agaricus bisporus have been investigated by fluorescent microscopy and scanning electron microscopy. Somatic nuclei, stained with auramin O and examined by fluorescent microscopy, appear to be randomly distributed, divide asynchronously, and assume a nonclassical or "two-track" configuration during mitotic metaphase. A similar configuration has been observed for nuclei during meiosis, but early meiosis in A. bisporus appears to be classical, usually with nine pairs of chromosomes evident during prophase I. Scanning electron microscopy has been used to document developmental stages in the formation and germination of basidiospores. Two-spored basidia were predominant, but occasionally one- or three-spored forms were observed. Four-spored basidia were absent, and uninucleated basidiospores were exceedingly rare to absent.

Basidiomycota↗
PubMed1979

Fluorescence microscopy for detection of M. leprae in tissue sections.

The fluorescence method was compared with the Fite-Faraco method for detecting acid-fast microorganisms in paraffin sections of cases of leprosy. Biopsies were obtained from 50 cases of leprosy covering all varieties and at varying stages of treatment. The fluorescence method was better than the Fite-Faraco method; 22 biopsies showing acid-fast organisms in fluorescence microscopy and 20 in the Fite-Faraco method. Its superiority was evidenced in two cases in which the organisms were very scanty. Fluorescence microscopy can also be used to determine the Bacterial Index and the Morphologic Index of organisms. The Morphologic Index, however, was one and a half times higher than that obtained by the Fite-Faraco technic. The ease and speed of fluorescence microscopy appear to be a great advantage.

Diagnosis, Differential↗
PubMed1978

Improved identification of methanogenic bacteria by fluorescence microscopy.

Methanogenic bacteria can be tentatively identified by fluorescence microscopy. This technique was improved by carefully selecting a series of excitation and barrier filters that matched the excitation and emission spectra of some unique coenzymes viz., F420 and F350, in methanogenic bacteria.

Escherichia coli↗
PubMed1977

[Fluorescence microscopy demonstration of mitochondria in tissue culture cells using berberine].

The possibility of fluorescence microscopical examination of mitochondria in living animal cells using fluorochrome berberine sulphate is shown. At concentrations of 30--50 g per ml the chemical is accumulated selectively in mitochondria of living cells. The specificity of berberine sulphate accumulation in mitochondria was shown by comparative phase contrast and fluorescence microscopy. The advantages of the method is its high sensitivity and simplicity, especially when mitochondria can not be examined by the phase contrast microscopy.

Animals↗
PubMed1979

Detection of mycoplasma contamination in tissue cultures by fluorescence microscopy.

The in situ staining method of Chen (1977) for the detection of mycoplasma contaminants in tissue cultures was tested in cultures of human skin fibroblasts after controlled contamination with Mycoplasma arginini. It is concluded that this method is reliable only at infection rates of 100% or higher, i.e., at one mycoplasma or more per tissue-culture cell.

Bisbenzimidazole↗
PubMedDate not supplied

Screening for Trichomonas vaginalis infection by use of acridine orange fluorescent microscopy.

The acridine orange test for detection of Trichomonas vaginalis in smears has been adapted for delayed examination of specimens. Mailed-in slides stained by acridine orange were compared with on-site wet mounts; the acridine orange test detected 96% of all positives, whereas only 76% were detected by wet mounts. In a similar comparison with Papanicolaou smears, the acridine orange test detected 89% as compared with 67% detected by Papanicolaou smears.

Acridine Orange↗
PubMed1977

Use of nuclepore filters for counting bacteria by fluorescence microscopy.

Polycarbonate Nuclepore filters are better than cellulose filters for the direct counting of bacteria because they have uniform pore size and a flat surface that retains all of the bacteria on top of the filter. Although cellulose filters also retain all of the bacteria, many are trapped inside the filter where they cannot be counted. Before use, the Nuclepore filters must be dyed with irgalan black to eliminate autofluorescence. Direct counts of bacteria in lake and ocean waters are twice as high with Nuclepore filters as with cellulose filters.

Bacteria↗
PubMed1976

Comparison of machine and manual staining of direct smears for acid-fast bacilli by fluorescence microscopy.

Comparisons were made in Lusaka and in London between manual staining and staining in an automatic machine with auramine-phenol of direct smears of sputum and other types of specimen for acid-fast bacilli. No evidence was obtained of carry-over of acid-fast bacilli from positive to negative smears during machine staining. There was improved contrast between bacilli and the background in smears prepared with the machine.

Benzophenoneidum↗