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Biomedical subjects

K R Castleman

Publications and source records attributed to K R Castleman.

9 recordsLinked to original sources
PubMed1992

The PSI automatic metaphase finder.

The Genetiscanner automatic metaphase finder (AMF) instrument manufactured by Perceptive Scientific Instruments, Inc. is capable of searching a microscope slide and generating a list of the stage coordinates of the metaphases within the 20 mm x 40 mm search area in ten minutes. It can process a cassette load of sixty slides in approximately ten hours, ranking the metaphases according to six categories of quality. It uses a robot arm to load and unload slides from a 60-slide cassette onto an automated microscope stage. It searches at approximately 1.5 sq. mm per second and uses automatic focus to keep the image sharp during the search. On good quality blood slides it detects greater than 80% of the metaphases with greater than 80% ranking accuracy and less than 20% false positives. It can also search amniotic fluid, bone marrow and mammalian cell culture metaphase preparations. The pattern recognition algorithms use classifiers specifically trained for each specimen type, and for the rejection of non-metaphase material. Such units have been in continuous operation for up to two years with good performance and reliability.

Cytogenetics↗
PubMed1988

Canonical analysis of cells in normal and abnormal cervical smears.

Over 4,000 cells from 105 normal and 96 abnormal uterine cervical scrapes were prepared according to the UCLA monolayer procedure, stained by a routine Papanicolaou method and visually classified by two cytopathologists and a technologist into seven classes: parabasal, metaplastic, mild dysplasia, moderate dysplasia, severe dysplasia, carcinoma in situ and invasive carcinoma. Canonical analysis was used to correlate effects-coded class membership variables with 23 cell features derived from digital image analysis. In general, nuclear texture measures derived from linear combinations of run-length correlations along with features derived from a Markov transitional probability matrix provided the best predictors of cell class. After cells were divided into benign (moderate dysplasia or less) and malignant (severe dysplasia or worse) groups, discriminant analysis correctly classified 84% of the benign cells and 91% of the malignant cells.

Cell Nucleus↗
PubMed1985

Quantitative histochemical determination of muscle enzymes: biochemical verification.

We established quantitative histochemical assays for the enzymatic activity of succinate dehydrogenase and alpha-glycerol phosphate dehydrogenase for cat skeletal muscle. A computer-enhanced image analysis system was used to quantitate the histochemical enzyme-activity reaction products. We describe a series of experiments that verify the reliability and validity of the assays. Histochemically determined enzyme activities were linear with respect to tissue thickness and reaction time. Biochemically determined enzyme activities were also linear with respect to tissue thickness and incubation time. Consecutive tissue sections, assayed either histochemically or biochemically, were used to establish a linear regression equation that allowed quantitative histochemically determined reaction rates, measured in optical density per minute, to be calibrated as nanomoles per minute.

Animals↗
PubMed1979

Morphology of the atrioventricular node, bundle and proximal bundle branches: a study employing computerized reconstruction.

The morphology of the human atrioventricular node, atrioventricular bundle and bundle branches is described. A block of tissue bounded by the ostium of the coronary sinus, the pars membranacea, the septal leaflet of the tricuspid valve and the atrial and ventricular septa is removed. The block is then sectioned serially from the right endocardial surface in the frontal plane of the heart. Sectioning in this way produces fewer sections than from techniques previously described. Outlines of the atrioventricular node, atrioventricular bundle and proximal bundle branches are digitally registered and stored in a computer. Three dimensional reconstructions of the structures are then generated by computer and displayed on an oscilloscope so that the entire three dimensional image can be rotated in any plane. Stereoscopic image pairs are produced to assist perception of the shape of the atrioventricular node, bundle and branching patterns of the bundles. This technique is unique in that it describes a method from which a relatively small number of histologic sections are generated permitting not only a complete histologic examination, but also a study of the morphology of the area.

Adult↗
PubMed1976

Karyotype analysis by computer and its application to mutagenicity testing of environmental chemicals.

Large scale population monitoring by cytogenetics would require vast amounts of effort for meaningful results. Computer techniques promise to assume some of this burden and thus render large scale monitoring a more practical alternative than it is now. A system recently developed at the California Institute of Technology, Jet Propulsion Laboratory and the City of Hope Medical Center, contains many of the features required by a large scale population monitoring system. One part of the system is a semi-automated slide preparation assembly which can process up to 576 specimens per day with uniform treatment. The second part of the system consists of a computer-controlled microscope which performs automatic slide search, metaphase location, and karyotype analysis under the interactive supervision of an operator. While the system was developed primarily for clinical cytogenetics, some aspects of our operating experience suggest promising approaches for population cytogenetics.

Chromosome Aberrations↗
PubMedDate not supplied

A simple method of producing a monolayer of cervical cells for digital image processing.

A manual method of producing a monolayer of isolated and evenly distributed cervical epithelial cells has been developed for use in an automated digital image analysis system. The cervical scrape specimen is vortexed from the spatula into a solution of Mucosol. The suspension is filtered through a 10 micro nylon mesh to remove polys and debris and then syringed to disaggregate epithelial clumps. The cells are plated out on a Nuclepore filter. The filter is touched directly onto a glass microscopic slide to transfer cells, which are then fixed and stained in a routine manner. Cell counts reveal elimination of 92% polys, with only 2% loss of squamous cells.

Autoanalysis↗