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J C Bisconte

Publications and source records attributed to J C Bisconte.

33 records · Page 2Linked to original sources

Automatic recognition of nervous structures by image analysis. A pattern recognition method applied to the study of mouse cerebellum.

An automatic image pattern analysis method based on differential densitometry is presented. It is applied to histological sections of mouse cerebellum. This method allows an automatic recognition of any cerebellar microscopic field. After recognition, histological images are decomposed into homogeneous parts with respect to cerebellar cellular layers, and both densitometric patterns and partial areas of each of these layers are estimated. This method is accurate to within 94% for a learning sample and 75% for a test sample. This score can be improved by adjunct algorithms presently under study.

Animals↗

[Quantitative study of autoradiographic marking in the rat nervous system. II. Final characteristics of the adult animal brain: interpretation rules and concept of cortical chronoarchitecture].

In this work a statistical study is made of the final outcome of the quantification of the nerve cell labelling in the adult, after prenatal injection of tritiated thymidine. This outcome is presented in the form of histograms which are the superposition of elementary Poisson distributions. A theoretical model, based on Probability theory, has been developed explaining the experimental outcome. Studying the final histograms of a defined region, according to this model, we can find out the number and the importance of the constitutive cell generations (chronology). From the graphic study of the percentage of labelled cells and that of the average of grains, the characteristics of the stratification of the neuronic populations/architectony) can be defined. All these notions have been gathered into a new concept: chronoarchitectony. This concept has also been applied to the neocortex. The results show that there is a strong interpenetration of the different cell generations in a given layer. The cortical neuronic production is a continuous phenomenon and there is no correspondence with the discontinuity of the cortical layers.

Animals↗

[Chronoarchitectonic analysis of the rat brain using radioautography. I. Histogenesis of the telencephalon].

1) Isocortex We find a centrifugal type chronoarchitectonic gradient with, however, a considerable overlap between the various generations of neurons. Thus in the older, deep layers (13.5 days) of the lateral neocortex 35% of the cells are chromologically incongruous (certain are very recent: 17.5 days and more). Cell production is a continuous process and has its peak towards 15.5 days of gestation. This refutes the existence of successive waves of cells. It is not possible to give even an approximate date to the isocortical layers, for the cortical laminations and the isochrones are nor concentric. What finally characterizes this structure from a chronoarchitectonic point of view is the considerable duration of the sequence of neuron production going from 13,5 days to birth. 2) Allocortex We find a centrifugal gradient in the paleocortex. In several of the structures of which it is composed a chronoarchitectonic incongruity can be attributed to the microneurons. It is the case with the islands of CALLEJA (in the olfactive tubercule) which separate very late on. In the archicortex the dominant gradient is again centrifugal. Here we find horizontal variations of the chronoarchitectonic patterns which are discussed with reference to the conception of a possibly fragmented cortex. 3) Striatum the chronoarchitectonic results largely confirm the diencephalic origin of the paleostriatum (STRASSER 1920, SPATZ 1921). In the archistriatum we find a steep rostrocaudal gradient, while the chronoarchitectonic heterogeneity of the structure tends to confirm the conception of a mixed origin (striatum and paleopallium). 4) Claustrum there is a real chronoarchitectonic incongruity between this structure and the isocortex. On one hand the sequence of the anterior part of the claustrum is of the paleostriate type. The posterior part is more probably archistriate. These findings suggest that the formation of the claustrum is of hybrid origin. 5) Septum The characteristic gradient of this formation is caudorostral. This gradient is practically common to all the structures except the telencephalon. We also find a centrifugal gradient related to the presence of a recent "cortex" which could be the counterpart of the cortical septal nuclei in superior mammals.

Amygdala↗

Detection of rare circulating breast cancer cells by filtration cytometry and identification by DNA content: sensitivity in an experimental model.

Current methods of detecting micrometastases in breast cancer fail in a large proportion of patients. Therefore an improved method for detection of metastases in blood samples could be of great clinical interest both for prognosis and selection of patients for adjuvant systemic therapy. We have developed a new non-invasive method which associates immuno-magnetic separation and filtration cytometry. The sensitivity of our procedure was evaluated in a model system using a mixture from a human breast cancer cell line (MCF-7) and a normal human blood sample. The identification of tumoral cells was achieved by measuring DNA content in comparison with standard cells. The lowest concentration of MCF-7 detected was 1 tumoral cell in 500,000 white blood cells. In addition, filtration cytometry provides a visual control of nuclei permitting the elimination of all doubtful cases and an automatic count of tumoral cells directly per ml of blood, which may be an independent predictor of early relapse. This new method may avoid unnecessary axillary lymph node dissection in patients with negative nodes. Our procedure seems suitable for the detection of rare circulating cells in routine laboratory testing and could be used in other applications.

Breast Neoplasms↗