Search PubMedSearch

PubMed · 374573

A thresholding method for automatic cell image segmentation.

Abstract

An algorithm for automatic segmentation of PAP-stained cell images and its digital implementation is described. First, the image is filtered in order to eliminate the granularily and small objects in the image which may upset the segmentation procedure. In a second step, information on gradient and compactness is extracted from the filtered image and stored in three histograms as functions of the extinction. From these histograms, two extinction thresholds are computed. These thresholds are suitable to separate the nucleus from the cytoplasm, and the cytoplasm from the background in the filtered image. Masks are determined in this way, and finally used to analyse the nucleus and the cytoplasm in the original image.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

H Borst, W Abmayr, P Gais. 1979. A thresholding method for automatic cell image segmentation.. https://doi.org/10.1177/27.1.374573

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related citations

The role of topoisomerase IV in partitioning bacterial replicons and the structure of catenated intermediates in DNA replication.

Mutants in bacterial topoisomerase (topo) IV are deficient in chromosomal partitioning. To investigate the basis of this phenotype, we examined plasmid DNA topology in conditionally lethal topo IV mutants. We found that dimeric catenated plasmids accumulated in vivo after topo IV inhibition. The catenanes were supercoiled, contained from 2 to > 32 nodes, and were the products of DNA synthesis. Electron microscopy and recombination tests proved that the catenanes have the unique structure predicted for replication intermediates. These data provide strong evidence for a model in which unlinking of the double helix can occur in two stages during DNA replication and for the critical role of topo IV in the second stage. The interlocks in the catenanes appear to be sequestered from DNA gyrase, perhaps by compartmentalization in an enzyme complex dedicated to partitioning.

Cell Compartmentation

Asymmetric distribution of oncogene products at mitosis.

Computer-assisted image analysis was used to demonstrate in exponentially proliferating human tumor cells the uneven postmitotic apportionment of several oncogene-encoded proteins (ras p21; erbB-2 p185; fos p55; myc p62). This observation may provide the explanation for the high degree of heterogeneity of postmitotic cells and the asynchrony in cell cycle traverse of cultured cells.

Cell Compartmentation

Structure and morphology of protein inclusion bodies in Escherichia coli.

We have studied the structure and characteristics of inclusion bodies formed by the enzyme beta-lactamase in the periplasmic space of Escherichia coli or in the cytoplasm, following expression of the protein without its signal sequence. Electron microscopy of highly purified protein aggregates using a novel sucrose gradient centrifugation procedure revealed striking morphological differences. Periplasmic inclusion bodies were essentially amorphous whereas the protein particles in the cytoplasm were highly regular. Depending on the cellular location, the inclusion bodies exhibited differences in protein composition even though they were formed by the expression of the same polypeptide chain. It was shown that the chaperonins GroEL and SecB are not incorporated into the inclusion bodies. Furthermore, the degree of solubilization of the inclusion bodies in the presence of denaturants and the sensitivity of the aggregated proteins to protease digestion indicated that the differences between cytoplasmic and periplasmic inclusion bodies extend to the conformation of the associated polypeptide chains.

Cell Compartmentation