Subject(s)
Lasers , Spectrometry, Fluorescence , Amino Acids/analysis , Coloring Agents , Krypton , Proteins/analysisABSTRACT
Picasecond temporal response and broad spectral response photodetectors have been fabricated using commercially available diode chips. Improved photoresponse sensitivity is achieved by removing the anode gold contact which obscures the active region. Junction geometry is such that the depletion region is approximately normal to the surface being illuminated, making the device especially useful for fast UV photodetection.
Subject(s)
DNA/metabolism , Meiosis , Spermatozoa/metabolism , Testis/metabolism , Animals , Crosses, Genetic , Cytological Techniques , DNA/genetics , Genetic Variation , Male , Mice , Mice, Inbred C3H , Spectrometry, Fluorescence , Spermatozoa/cytology , Spleen/cytology , Spleen/metabolism , Testis/cytologyABSTRACT
The DNA content of individual sperm from populations of acriflavine-stained cells was investigated by analysis of fluorescence frequency distributions obtained with high-resolution flow-systems instruments. Sperm with spherical or cylindrical heads from three mollusk species produce narrow, symmetric fluorescence distributions. Flat sperm heads from six eutherian species produce asymmetric distributions consisting of a peak with a lateral extension to higher fluorescence values. The unexpected shape of these distributions was shown to be due to the flat geometry and high refractive index of the sperm heads in conjunction with the orthogonal axes of flow, excitation, and detection in the flow-systems instruments. The theoretical and experimeytal results indicate that the lateral extension can be eliminated either by controlling the sperm orientation with planar flow conditions or by accounting for sperm orientation by means of orientation sensing.
Subject(s)
Spermatozoa/analysis , Acridines , Acriflavine , Animals , Cricetinae , Ethidium , Male , Mice , Mollusca , Octopodiformes , Ostreidae , Rabbits , Species Specificity , Spectrometry, Fluorescence , Sperm Head/analysis , Spermatids/analysis , Spermatozoa/cytology , Staining and LabelingABSTRACT
We describe a new flow-system technique for high-speed quantitative karyotyping. Metaphase chromosomes are isolated from cells, stained with a DNA-specific fluorochrome, and individually measured for stain content at rates up to 10(5)/min in a flow microfluorometer. The resulting distribution contains quantitative information about the relative frequency of occurrence and the chromosomal DNA content of the measured chromosomes. Such analyses of Chinese hamster chromosomes are in good agreement with independent results from scanning cytophotometry and with cytogenetic observations of the banded chromosomes. Analyses of two karyotypically different clones of Chinese hamseter M3-1 lines provide the quantitative characterization of two stable translocations. Initial data on human chromosomes are presented and agree well with results of scanning cytophotometry and suggest potential clinical applications as preparative and instrumental techniques improve.
Subject(s)
Karyotyping/methods , Animals , Autoanalysis , Cell Line , Chromosomes/analysis , Chromosomes/ultrastructure , Clone Cells , Cricetinae , DNA/analysis , Diploidy , Evaluation Studies as Topic , Humans , Male , Microchemistry , Microscopy, Fluorescence/instrumentation , Skin/analysis , Time FactorsABSTRACT
A flow microfluorometer was used to measure metaphase chromosomes in suspension at rates up to 100,000 per min. Chromosomes from cells of the Chinese hamster M3-1 cell line were isolated, stained for DNA with the fluorescent dye ethidium bromide, and analyzed for DNA content. Nine distinct peaks were resolved that correspond well with independent chromosomal DNA measurements made with a high-resolution scanning cytophotometer. Chromosomes were sorted from each peak by an electronic cell sorter. Visual examination of each fraction indicated the purity of the sorted chromosomes. This novel technology allows separation of purified populations of individual chromosomes suitable for biochemical and biological characterizations.
Subject(s)
Chromosomes/ultrastructure , Animals , Cell Line , Chromosomes/analysis , Clone Cells , Cricetinae , DNA/analysis , Methods , Microscopy, Fluorescence , MitosisABSTRACT
We report the development of an electrooptic cell consisting of a cylindrical sample of Z-cut KD*P with a ring-electrode geometry for applying voltage to the crystal. Theoretical analysis and experimental results demonstrate that this cell design results in high transmission uniformity across the cell aperture and subnanosecond switching capability. Compared with cell of conventionaldesign, the new cell permits an order-of-magnitude improvement in transmission uniformity as well as improved switching speed.
