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G C Salzman

Publications and source records attributed to G C Salzman.

16 recordsLinked to original sources
PubMed1990

Introduction to flow cytometry data file standard.

The Data File Standards Committee of the Society for Analytical Cytology presents a Standard to be used for the storage of data associated with flow cytometric measurements. The Standard specifies a format that provides for the inclusion of all information necessary to fully describe: 1) the instrument used for the measurement; 2) the sample measured; 3) the data obtained; and 4) the results of analysis of the data. The Committee and the Society for Analytical Cytology point out that the use of this Standard by all those individuals and companies that generate or use data taken with flow cytometers or generate methods of analysis for the data will encourage the sharing of such data and methods of analysis.

Flow Cytometry↗
PubMed1988

Knowledge-engineering software. A demonstration of a high-end tool.

Many investigators wanting to apply knowledge-based systems (KBSs) as consultants for cancer diagnosis have turned to tools running on personal computers. While some of these tools serve well for small tasks, they lack the power available with such high-end KBS tools as KEE (Knowledge Engineering Environment) and ART (Automated Reasoning Tool). These tools were originally developed on Lisp machines and have the full functionality of the Lisp language as well as many additional features. They provide a rich and highly productive environment for the software developer. This paper illustrates the capability of one of these high-end tools. First, a table showing the classification of benign soft tissue tumors was converted into a KEE knowledge base. The tools available in KEE were then used to identify the tumor type for a hypothetical patient.

Age Factors↗
PubMed1985

Circular dichroism studies on single Chinese hamster cells.

The circular dichroism (CD) and circular intensity differential scattering (CIDS) contributions to the CD of single Chinese hamster (CHO) cells have been measured as a function of the position in the cell cycle. The data are analyzed in three main spectral regions: (1) the region above 290 nm (scattering region), (2) the 250-290-nm regions (nucleic acid absorption region), and (3) the region below 240 nm (protein absorption region). The results show that CD/CIDS microspectrophotometry is a good indicator of the cell cycle phase. The results are consistent with the view that chromatin is organized in chiral superstructures which differentially scatter circularly polarized light. These structures appear highly specific and repeatable as the cell passes through its cycle.

Animals↗
PubMed1979

Multiangle light scattering flow photometry of cultured human fibroblasts: comparison of normal cells with a mutant line containing cytoplasmic inclusions.

Multi-angle light scattering flow photometry was used to study the light scattering properties of normal cultured fibroblasts and a mutant fibroblast line containing cytoplasmic lysosomal inclusions. The effect of glutaraldehyde fixation on the light scattering properties of the cells was also examined and correlated with their ultrastructure. Normal fibroblasts showed uniform organelle distribution with few vacuoles or dense bodies in the cytoplasm while the mutant line showed abnormal cytoplasmic inclusions of varying morphology, density and lucency. As predicted by light scattering theory, the mutant cells containing the cytoplasmic inclusions scattered more light at large angles (greater than theta = 1.85 degrees) than did the normal cells. Glutaraldehyde fixation decreased light scattering at small angles (less than theta = 1.85 degrees), increased light scattering at larger angles (greater than theta = 1.85 degrees) in both normal and mutant cells and enhanced resolution of the light scattering signatures. The mutant line scattered 2-3 times more light at a wide angle (greater than theta = 12.74 degrees) than did the normal cells. These data suggest that abnormal lysosomal storage inclusion bodies in the cytoplasm of the cells can be detected by differential light scattering methods.

Cell Line↗
PubMed1979

Light scattering with stream-in-air flow systems.

Both forward angle and 90 degrees light-scattering measurements have been used for cell sizing with stream-in-air flow systems with very little theoretical base for the measurements. Mie theory calculations are compared with measurements on plastic microspheres. Detector response for homogeneous spheres is shown to be sensitive to refractive index.

Cell Count↗
PubMed1978

Light-scatter analysis of microalgae. Correlation of scatter patterns from pure and mixed asynchronous cultures.

A method is described for the first time for rapid and accurate discrimination among several algal types by their light-scattering properties alone. Using a multiangle light-scattering flow system, we obtained light-scatter patterns for individual cells in asynchronous cultures of Chlorella, Chlamydomonas, and Anacystis. The patterns are consistent and distinct for each species. By these signatures, each algal type can be recognized within mixtures.

Chlamydomonas↗
PubMed1977

A high efficiency flow cytometer.

A flow chamber has been developed which collects about 60% of the total cell fluorescence for analysis compared to about 2.5% for conventional flow systems. The chamber, an ellipsoid of revolution, is gold-plated for increased reflectivity. Fluorochrome-stained cells enter the flow cell directly above the primary focus of the ellipsoid at the rate of 1000 cell/sec. A focused argon-ion laser beam enters the flow cell parallel to the semiminor axis and intersects the cell stream at the primary focus. Fluorescent light emanating from this point is reflected toward the secondary focus, where it exits the chamber for analysis. The high efficiency flow cytometer has been used to obtain nucleotide fluorescence distributions from samples of Micrococcus glutamicus bacteria stained with propidium iodide and of spermatozoa stained by the acriflavine-Feulgen procedure.

Cytological Techniques↗
PubMed1976

Pulse-height light-scatter distributions using flow-systems instrumentation.

Several laboratories have recently been making light-scatter measurements on cells and other particles using flow-systems instrumentation. We at the Los Alamos Scientific Laboratory, as well as others, have obtained multimodal pulse-height distributions in certain angular regimes from particles of supposedly uniform characteristics. Because it was assumed that multimodal distributions implied characteristics of multivalue, the accuracy of such data has been doubted. In the present work, pulse-height distributions anticipated on the basis of exact electromagnetic theory were calculated for particles of known characteristics. These calculated pulse-height distributions agree quite well with those obtained experimentally. Physical optics form the basis for the explanation of the complex pulse-height distributions obtained experimentally. However, the results of this study show that certain cautions are necessary in the interpretation of light-scatter data presented in this manner.

Autoanalysis↗
PubMed1976

Gynecologic specimen analysis by multiangle light scattering in a flow system.

A flow-system instrument is described in which the laser light scattered by a mammalian cell is sampled simultaneously at up to 32 angles between 0 degrees and 21 degrees from the laser beam axis as the cell passes through the beam. The scatter pattern for each cell is stored by a computer for later analysis. Various data-processing techniques are discussed. Results of preliminary application of the instrument to the analysis of normal and abnormal gynecologic specimens are presented.

Autoanalysis↗
PubMed1975

A flow-system multiangle light-scattering instrument for cell characterization.

A flow-system cell-analysis instrument is described in which cells from a heterogeneous population are characterized by their light-scatter patterns alone. As the cells pass at high speed through a focused helium/neon laser beam, the scatter pattern from each cell is sampled simultaneously at up to 32 angles between 0 degrees and 30 degrees with respect to the laser beam axis, and the scatter pattern for each cell is transferred to a computer. A mathematical clustering algorithm is used to determine the number of classes into which the cells can be divided, and a linear separation algorithm is used to find the boundaries between the classes. Preliminary results on exfoliated cells from gynecological specimens are presented. This technique may be useful for automated prescreening of gynecological specimens.

Autoanalysis↗
PubMedDate not supplied

Cell classification by laser light scattering: identification and separation of unstained leukocytes.

We have used a flow-system cell sorter to separate unfixed, unstained human leukocyte cells into morphologically distinct populations based only on the intensity of 488-nm wavelength laser light simultaneously scattered by each cell at two different angles. Three populations were observed as distinct peaks in a two-parameter pulse-height distribution and were then physically sorted into separate classes and stained for cytological examination. The three groups consisted of lymphocytes, monocytes, and neutrophils. Each group contained between 77 and 98 per cent of a single cell type. Blood from an irradiated monkey was also sorted and showed the presence of a fourth peak which consisted of 61 per cent eosinophils. Thus, multiangle light-scattering information from unfixed, unstained cells may be a promising technique for rapid morphologic analysis and may have application, for example, as a highspeed automated leukocyte differential. We anticipate that this method may be useful in other clinical applications where morphologic differences are diagnostically important. One of the principal advantages of the method is elimination of fixation and staining of the samples; this is a nondestructive testing technique.

Animals↗