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Biomedical subjects

C Souchier

Publications and source records attributed to C Souchier.

At least 55 records · Page 3Linked to original sources

An image cytometric DNA-analysis in breast neoplasms. Parameters of DNA-aneuploidy and their relationship with conventional prognostic factors.

In this prospective study, an image cytometric DNA-analysis was performed in 86 women with breast neoplasms (72 primary invasive carcinomas and 14 benign lesions). Four DNA ploidy parameters were analysed: histogram type (according to AUER classification), DNA-index, tumor cells with DNA content above the 5n limit and DNA malignancy grade (DNA-MG, calculation according to Böcking). Their correlations with well established prognostic factors in breast carcinomas (tumor size, lymph node status, histologic grade, hormone receptor content) were studied. All but one benign lesions were diploid (13/14 cases), whereas the majority of the primary invasive breast carcinomas were aneuploid (58/72 cases). A predominance of carcinomas with a percentage of cells superior or equal to 1% with DNA content above the 5n limit was observed (54 cases out of 58). Most of the aneuploid tumors had a histogram type III or IV (53 cases) or a high DNA-index (50 cases). Of these 58 aneuploid cases, only 26 tumors had a DNA-MG superior to 1. Interestingly, 26 tumors had the 4 criteria of aneuploidy, 19 had 3 and 9 had 2 and only 4 tumors had one parameter. The DNA-MG was significantly related to hormonal receptors (p less than 0.001) and tumor size (p less than 0.01). The histogram types (Auer classification) and the DNA content above the 5n limit were correlated with histologic grade (SBR or SBRM) (p less than 0.02). Concerning the DNA-index no correlation was observed with well established prognostic factors. On the other hand no significant correlation was found between these new biologic variables and lymph node status.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

Is there an accumulation of cells during G2 in some acute lymphoblastic leukaemias?

In some cases of acute lymphoblastic leukaemia (ALL) the percentage of cells in G2 + M is higher than anticipated when compared with the percentage in S phase. This increase in G2 + M, as detected by flow cytometry measurement of DNA content, may be due to an accumulation of cells, either in G2 or during the end of S phase; it may also be related to the existence of small tetraploid clones generally ignored by cytogeneticists. In order to identify possible subpopulations of cells with a DNA index greater than or equal to 2.0, we have compared the results of a cytogenetic analysis to the G2 + M values. We have also studied the distribution of S phase cells in 24 cases of ALL by incorporating 5-bromodeoxyuridine, labelling the cells by indirect immunofluorescence, and analysing them by flow cytometry after propidium iodide staining. The distribution of cells during S phase was quantified: no accumulation of cells was ever observed at the end of S phase. The question of the existence of small tetraploid clones, G2 arrested cells or cells with a G2 elongation remains open. However, we feel that it is more probable that, in this pathology, an elongation of the duration of G2 occurs.

Adolescent↗

Morphometric modifications associated with early sensory experience in the rat olfactory bulb: II. Stereological study of the population of olfactory glomeruli.

The present study explores the local variations of size and number of olfactory glomeruli induced by the exposure of young rats to long-term stimulation with a single odor. Three groups of 5 rats were used that were either: (1) stimulated with ethyl acetoacetate from birth to 1 month of age, (2) unilaterally deprived following early occlusion of one nare, or (3) normal animals of the same age. Areas and coordinates of all glomerular profiles were measured in 14 coronal sections uniformly distributed along the rostrocaudal axis of the olfactory bulb. A distribution-free stereological method was applied to compute the size and number of glomeruli either along the bulbar rostrocaudal extent or in the bulbar coronal plane. Following complete sensory deprivation or long-term stimulation with ethyl acetoacetate, the mean diameter of glomeruli was significantly reduced everywhere, except in the ventrolateral and ventromedial regions of the posterior olfactory bulb in rats reared with a single odor. In both of these areas, the number of glomeruli was either significantly increased following long duration exposure or significantly reduced following unilateral deprivation. Thus these results show that selective modifications of the olfactory environment during postnatal maturation induce morphometric variations in specific areas of the glomerular layer. These data are discussed with respect to the concept of the topographical coding of odor quality at the level of the glomeruli and plasticity of the olfactory system during postnatal development.

Acetoacetates↗

Comparison between image and flow DNA cytometry in non-Hodgkin's lymphomas.

To assess the reliability of DNA estimation in cytological material, Feulgen lymph node imprints from 22 cases of malignant non-Hodgkin's lymphomas were examined by image cytometry (ICM) for both ploidy and cell kinetics, and the results obtained were compared with flow cytometry (FCM). The DNA distribution pattern was less accurate with ICM than with FCM; however, a high correlation was found between proliferative indices (r = 0.91) and between aneuploidy rates (agreement in about 86% of the cases) determined by FCM and ICM. Moreover, DNA tetraploid (or near-tetraploid) stem lines were more easily detected by ICM, due to the morphological selection of lymphomatous cells. The proliferation rate and the aneuploidy frequency according to morphological classification were in agreement with larger, previously reported studies with FCM. Therefore, ICM appears to supply additional complementary information to that obtained with FCM, particularly for the study of heterogeneous cell populations, which may be usefully applied to refine the large cell lymphoma subclassification.

DNA, Neoplasm↗

DNA assessment in thin sections of lymphomas by densitometric and stereological methods: comparison with imprint and flow cytometric results.

The nuclear DNA content was estimated in 2 microns sections of 18 lymphoma cases by two methods: (1) Feulgen densitometry using QTM 900 with correction by Bins' procedure which allows size-independent DNA distributions; (2) stereological unfolding as proposed by Cruz-Orive giving sphere-size distributions. A general correlation was found between results and DNA measurements obtained by imprint and flow cytometric techniques in the same specimens. When histologic DNA profiles were compared to cytologic histograms, a high correlation was found between the distribution of ploidy classes by correspondence analysis. However two highly proliferating lymphomas were erroneously classified as aneuploid. Conversely, sphere-size distributions allowed the identification of the majority of aneuploid lymphomas but failed to recognize proliferating ones. It appears that when cytologic specimens are not available, densitometric studies on sections may provide valuable information on DNA content, with complementary data obtained from stereological procedures.

Aneuploidy↗

Morphometric study of the glomerular population in the mouse olfactory bulb: numerical density and size distribution along the rostrocaudal axis.

A morphometric study of the glomerular population in the olfactory bulb of the mouse has been carried out by using stereological methods. On the basis of the assumption that the glomerular population is a polydispersed system of spheres, glomerular profile distributions obtained from profile measurements were subjected to a mathematical unfolding procedure to obtain the actual glomerular size distribution. We used a distribution-free method to account for the combined effects of overprojection due to section thickness and truncation (two missing profile mechanisms). Results proved better than those obtained directly from profile measurements without stereological analysis. Several new findings were obtained. First, significant variations of the glomerulus sizes were found along the rostrocaudal axis. The glomeruli are larger in the middle region of the olfactory bulb, whereas their numerical density decreases in the same region. Moreover, the profile density is homogeneous along the rostrocaudal axis. In other words, the relative surface occupied by the periglomerular cells in the glomerular layer is invariant. As a consequence, it may be concluded that the variations in size and numerical density are inversely correlated. Thus, since the glomeruli are larger in the middle region, their number per unit volume is logically smaller in this same area. Finally, the computerization of all these data has led us to estimate the number of glomeruli (1,810 +/- 41) in the olfactory bulb of the mouse. In order to get a comparative idea of their advantages and disadvantages, other standard stereological methods were used in the present study to determine this number. Functional interpretations of the variations of the size and numerical density along the rostrocaudal axis of the olfactory bulb are discussed with respect to ontogenetic and morphofunctional data obtained elsewhere.

Algorithms↗

Image analysis applied to proliferating cells in malignant lymphoma.

This study describes a method for obtaining the distribution of a given cell type in histological sections, as revealed by a specific immunological marker. Two hundred fifty-six contiguous microscopic fields were analysed, and a cellular map was automatically constructed. The resulting images were stored on magnetic media for subsequent quantification and statistical tests. The method was applied to the analysis of 20 small cleaved-cell lymphomas in which the monoclonal antibody Ki-67 was used to mark proliferating cells. Clusters of proliferative cells were observed in both diffuse and nodular lymphomas. Cellularity and the percentage of marked cells were not significantly different in the two types of tumors.

Antibodies, Monoclonal↗

Three-dimensional ultrastructure and quantitative analysis of the human Sertoli cell nucleolus.

The nucleolus of the human Sertoli cell displays a spontaneous segregation of its components and has only one or 2 large fibrillar centers. The 3-dimensional reconstruction and quantitative analysis of its components was undertaken using a Quantimet 900 image analysis system in order to define the spatial relationships between the dense fibrillar component and the fibrillar center and especially to investigate whether threads of dense fibrillar component exist independently, without being linked to a fibrillar center. Our 3D reconstructions demonstrated that the dense fibrillar threads or sheets were never independent of fibrillar centers. These structures belonged to a continuous network that joined the layer of dense fibrils surrounding the fibrillar center. When the nucleolus contained 2 different-sized fibrillar centers, quantitative analysis showed that there was a proportional relationship between the volume of the dense fibrillar component and the volume of the fibrillar center. These data, compared with those previously obtained by means of autoradiographic techniques, suggest that the rDNA-containing chromatin passes through the fibrillar center and unwinds from there into the dense fibrillar component.

Cell Nucleolus↗

Specificity of spatial patterns of glomerular activation in the mouse olfactory bulb: computer-assisted image analysis of 2-deoxyglucose autoradiograms.

We have developed a computer-assisted method for analyzing the 2-deoxyglucose (2-DG) autoradiograms of mice olfactory bulbs. The purpose of the study was to numerize the maps of glomerular activation in order to achieve a statistical comparison of the glomerular patterns evoked by different stimuli. The spatial distribution of glomerular activation was displayed on unfolded representations of the glomerular layer which were built up using glomerular optical densities (OD) measured systematically within 13 sections per bulb. Each bulbar sample was converted into an 'OD profile'. A matrix composed of 18 OD profiles was submitted to a principal component analysis. The first factor which accounted for 28% of the variance separated unambiguously two clusters corresponding to the bulbs issued from animals stimulated with amylacetate and isovaleric acid, respectively. The second and third factors which accounted for 14% and 12% of the variance segregated the control group (animals exposed to pure air) from the odor-stimulated ones. It was demonstrated that the cluster separation was actually due to the specific spatial distribution of the most-labelled glomeruli. A particular attention was paid to the well-delineated glomerular activation evoked by isovaleric acid. The results demonstrate the specificity and reliability of the glomerular 2-DG patterns. The method should be useful for further comparisons of patterns elicited by larger sets of odorant compounds.

Animals↗

Three-dimensional analysis of fibrillar centers and associated chromatin in the nucleolus of human oocytes in primordial follicles.

The intranucleolar localization of fibrillar centers and their relationships with nucleolus-associated chromatin were determined in stereopairs of human oocyte nucleoli obtained by computer reconstruction of serial sections. This study showed that there was no numerical relationship between the number of fibrillar centers and the number of chromosomal NORs. The three-dimensional reconstruction demonstrated that the majority of fibrillar centers was directly connected with the nucleolus-associated chromatin.

Adult↗

Individual characteristics of human spermatozoa.

We have investigated the variability of some characteristics of a sperm sample in 18 young volunteers in good health who were examined twice per month over a period of two years, and in about one hundred men undergoing treatment for sterility and for whom more than 4 spermiograms had been established during the past three years. The results of statistical analysis indicate that the most characteristic individual feature is the concentration of spermatozoa.

Humans↗

Morphometric studies of cell nuclei by means of image analysis and computer data processing.

A review of the recent results of the authors in the field of morphometric studies of Feulgen-stained cell nuclei is given. The data acquisition with Quantimet 720 and data processing with computer were used in the study. The discrimination between male and female cell nuclei from buccal smears on the basis of morphometric data is described. The morphometry-based classification of cells from vaginal smears according to the computer procedure is presented. The results are discussed in the context of the general strategy of morphometric work.

Animals↗

Effect of tenotomy on self-reinnervated and randomly reinnervated soleus muscle of rat.

The time course and degree of atrophic changes caused by tenotomy were compared in normal, self-reinnervated and randomly reinnervated soleus muscle 6 months after transsection and reunion of the nerve at different distances from the muscle. Comparison was made between the behaviour of Type I and Type II fibers, distinguished on the basis of histochemical myofibrillar ATPase and succinic dehydrogenase reactions. Cross-sectional areas of individual muscle fibers were measured using Quantimet 720 image analyser. Selective atrophy of Type I muscle fibers as determined by structural and histochemical changes was observed after tenotomy of normal, self-reinnervated and randomly reinnervated soleus muscles after transsection of the muscular branch of the tibial nerve, Type II muscle fibers in randomly reinnervated muscles were found to be relatively insensitive to tenotomy, as in normal muscle. In randomly reinnervated muscles after transsection and reunion of the sciatic nerve, tenotomy did not cause any visible structural and histochemical abnormalities although a decrease of muscle weight and cross-sectional surface area of fibers was noted. Since in these muscles Type II fibers increased to about 70% of the muscle fiber population, it is suggested that the increased percentage of Type II fibers seemed to prevent the atrophic changes in Type I fibers after tenotomy.

Animals↗

DNA content of cells in human buccal smears. A preliminary study.

The DNA content of the cells from human buccal smears, stained by the Feulgen method, was estimated by absorbtion microdensitometry using a Quantimet 720 D image analyser. It was concluded from measurements that most of the cells in buccal smears contained 2C DNA; however, among the cells from male donors a substantial proportion of cells (about 17%) contained less than 2C DNA. This difference between population of male cells versus female cells was statistically significant. The mean value of DNA content was estimated to be 7.7% lower for male cells than for female cells. The conclusions are preliminary because relatively small samples of cells have been measured.

Cheek↗

[Disturbances in ovulation following on artificial insemination with donors (A.I.D.) (author's transl)].

The authors report on the results of statistical analysis of temperature curves in 139 patients before artificial insemination from donors (A.I.D.) and in the cycles in which they were inseminated. It appears that frequently the practice of A.I.D. causes ovulation to come early or late. Late ovulation seems to be the most frequent cause of failures which are then considered to be due to "psychogenic sterility".

Female↗