Biomedical subjects

W E Tolles

Publications and source records attributed to W E Tolles.

10 recordsLinked to original sources

PubMed1982

Cytologic cell collection, suspension and preservation for automated screening procedures.

Since disaggregation for monodispersion is optimal when the specimens are suspended in solutions of low alcohol content, we evaluated a modified Davis' solution as a collection and suspension medium. The preservation of specimens maintained at room temperature (21 C) in this solution, which contained only 10% ethanol instead of the usual 20%, was evaluated both qualitatively and quantitatively. Control slides were made on day 1, and experimental slides were made on days 3, 7, 14, 21 and 28. The slides were evaluated by a cytotechnologist and confirmed by a pathologist for the onset of degenerative changes and loss of diagnostic value. The slides were also quantitatively analyzed by a semiautomatic instrument, the Cyto-Tally, adding substantial numerical value to the inquiry. The fragility of leukocytes was evident by the 14th day. Squamous cell degeneration was seen in the interval between two and four weeks depending on the initial state of the specimen. However, the specimens were of diagnostic value for up to four weeks.

Cell Aggregation↗

PubMed1977

Enrichment of the gynecologic cytologic specimen.

The principal objective of our group has been and continues to be the improvement of the biologic signal-to-noise ratio of the gynecologic cytologic specimen through: the dispersal of clusters and clumps, enrichment of the abnormal component of the dispersed specimen by the method of rate-zonal sedimentation under unit gravity, and monitoring the effects of these manipulations with biophysical non-destructive methods. This report is concerned only with presenting the current status of the effectiveness of our enrichment techniques both qualitatively and quantitatively. Zonal sedimentation creates a broad spatial spectrum of cells by virtue of their different velocities which are directly related to their areas. Certain fractions of this spectrum are extracted, concentrated and deposited on slides for subsequent manual differential analysis, evaluation and documentation. Qualitatively, fractions M1 and M2 show impressive removal of erythrocytes, leukocytes and debris. Quantitatively, enrichment factors vary from 0.1 (depletion) to as high as 26 yielding an average enrichment of about 6, a most rewarding improvement.

Cell Separation↗

PubMed1977

Ultrasonic disaggregation of cell clusters.

A technique of cluster disaggregation has been developed and applied to cervical cells in suspension. Preliminary results indicate that ultrasound is capable of cluster disaggregation under controlled energy conditions. Cytologic quality of the resulting preparation is adequate for cell analysis in flow systems.

Cell Separation↗

PubMed1976

Quantitation of the rate-zonal sedimentation spectrum.

Rate-zonal sedimentation of cells from the female genital tract has been employed as a means of separating many of the different cellular components from each other. Ultra-slow streak photography of forward scattered light from the sedimentation spectrum has been used as a monitor of the success of the individual sedimentation maneuver. The presence of convention currents vitiates the separation potential of the technique, and this is readily detected by the photographic monitor. In addition, these photographs clearly indicate the positions of bands of cellular entities of different sedimentation velocities. Further study of the quantitative aspects of the light scattered from each part of the spectrum reveals that it possesses a quantitative representation of the concentration of cells at each level of the spectrum. The photographs and densitometric scans support these expectations. To avoid the limitations of film as a data-logging medium and to obtain real-time system utilization, a direct photoelectric scanner has been assembled. Preliminary tests indicate ready feasibility.

Centrifugation, Zonal↗

PubMed1970