Biomedical subjects

M Petein

Publications and source records attributed to M Petein.

At least 37 records · Page 2Linked to original sources

PubMed1997

Biochemical alterations of the tunica albuginea in impotence.

PURPOSE: The objectives of this study were to quantify the immunohistochemical stainings of collagen types I, III and IV, and investigate the value of glycohistochemical staining with 3 lectin types specific to a particular glycan structure, Arachis hypogaea, Triticum vulgare and concanavalin A, as a method of defining possible changes in the collagen structure of the tunica albuginea in potent and impotent patients. MATERIALS AND METHODS: The study involved 4 normal men, 4 with pure venous leakage and 4 with pure arterial disease. Collagen types I, III and IV, and lectins Arachis hypogaea, Triticum vulgare and concanavalin A were studied using a cell image processor. The labeling index relates to the percentage of staining and mean optical density relates to the staining intensity. RESULTS: Mean labeling index values for the 3 types of collagen and lectins were similar (p > 0.05). Mean optical density value relating to collagen type I was significantly higher in the arteriogenic group than in the other groups (p < 0.05), while mean optical density value of collagen type IV was significantly higher in the venogenic group than in the 2 other groups (p < 0.05). Mean optical density values relating to the 3 lectin types were similar in the 3 clinical groups (p > 0.05). CONCLUSIONS: An alteration in the distribution and structure of the various collagen types and lectins in the tunica albuginea of impotent patients has been shown that may interfere with normal function and lead to impotence.

Adult↗

PubMed1997

Decision tree induction: a useful tool for assisted diagnosis and prognosis in tumor pathology.

The aim of the present work is to show that decision tree induction algorithms are a useful tool for extracting reliable information from data series, with the objective of assisting pathologists in identifying specific diagnostic and prognostic markers in various types of tumor pathologies. In terms of accuracy, we show that the decision tree technique exceeds other more sophisticated techniques, such as multilayer neural networks. Furthermore, because of the case with which decision tree results can be interpreted (logical classification rules), new methodologies can be readily developed to further assist in analyzing complex data that mix heterogeneous features. In this paper, we illustrate such capabilities in the context of different complex diagnostic and/or prognostic problems in tumor pathology relating to bladder, astrocytomas, and adipose tissues.

Adult↗

PubMed1997

Contribution of quantitative lectin histochemistry to characterizing well-differentiated, dedifferentiated and poorly differentiated liposarcomas.

OBJECTIVE: To find new diagnostic markers in the group of lipomatous tumors. STUDY DESIGN: The histochemical lectin staining pattern was characterized in a series of 45 lipomatous lesions, including 10 typical lipomas, 6 atypical lipomas, 8 well-differentiated, 6 myxoid, 5 dedifferentiated and 10 pleomorphic liposarcomas. Three lectins were used-peanut (Arachis hypogaea) agglutinin, which binds to terminal Gal(beta 1,3)GalNAc residues; wheat germ (Triticum vulgare) agglutinin (s-WGA, the succinylated form of WGA), which binds to ((1-4)-D-GlcNAc)n and Neu5NAc residues; and jack bean (Concanavalia ensiformis) agglutinin which binds to alpha-D-Man and alpha-D-Glc residues. Histochemical staining was quantitatively measured by means of a cell image processor. RESULTS: In the case of certain carbohydrate residues, typical lipomas closely resemble atypical lipomas, which in turn closely resemble well-differentiated liposarcomas; typical lipomas differ significantly from well-differentiated liposarcomas. This indicates that atypical lipomas, or at least some of them, could represent a biologic link between typical lipomas and well-differentiated liposarcomas. While well-differentiated and pleomorphic liposarcomas differed significantly from each other, the poorly differentiated component of dedifferentiated liposarcomas included histochemical lectin properties, which were common to both well-differentiated and pleomorphic liposarcomas. CONCLUSION: Some atypical lipomas exhibit glycohistochemical characteristics that are common to those of well-differentiated liposarcoma. The poorly differentiated component of dedifferentiated liposarcomas remains more differentiated in terms of glycohistochemical markers than do poorly differentiated pleomorphic liposarcomas.

Adult↗

PubMed1996

Methodological aspects of using decision trees to characterise leiomyomatous tumors.

The aim of the present work is to present the potential uses of a classification technique labeled the "decision tree" for tumor characterisation when faced with a large number of features. The decision tree technique enables multifeature logical classification rules to be produced by determining discriminatory values for each feature selected. In this report, we propose a methodology that used decision trees to compare and evaluate the information contributed by different types of features for tumor characterisation. This methodology is able to produce a set of hypotheses related to a diagnosis and or prognosis problem. For example, hypotheses can be producted (on the basis of a set of descriptive features) to explain why tumor cases belong to a given histopathological group. To illustrate our purpose, this methodology was applied to the difficult problem of leiomyomatous tumour diagnosis. The aim was to illustrate what kind of diagnostic information can be extracted from a sample data set including 23 smooth muscle tumors (14 benign leiomyomas and 9 malignant leiomyosarcomas) described by a large set of computer-assisted, microscope-generated features. Three groups of features were used relating to: (1) ploidy level determination (10 features), (2) quantitative chromatin pattern description (15 features), and (3) immunohistochemically related antigen specificities (6 features). All these features were quantified by digital cell image analysis. The results suggest that an objective distinction between leiomyomas and leiomyosarcomas can be established by means of simple logical rules depending on only a few features among which the immunohistochemically revealed antigen expression of desmin plays a preponderant part. One of the combinations of features proposed by the methodology is interesting for pathologists, because it includes two features describing the appearance of a nucleus in terms of chromatin distribution homogeneity and density, two features widely used by pathologists in tumor-grading systems.

Adolescent↗

PubMed1996

In vitro characterization of prolactin-induced effects on proliferation in the neoplastic LNCaP, DU145, and PC3 models of the human prostate.

BACKGROUND: Proliferation of normal and tumoral prostate tissue is regulated by androgens and various growth factors. We characterized the in vitro proliferative influence of prolactin (PRL) in androgen-sensitive and androgen-insensitive human prostate cancers. METHODS: The biologic models employed included the androgen-sensitive LNCaP and the androgen-insensitive DU145 and PC3 cell lines. PRL-induced influences (0.1-10 mIU/ml of medium) on proliferation were assessed using the colorimetric methylthiotetrazole assay. Androgen sensitivity in the three cell lines was determined by assessing the proliferative influence of dihydrotestosterone (DHT) (0.1-10 nM). PRL-induced modifications in PC3 cell kinetics were assessed using Feulgen-stained nuclear image cytometry. RESULTS: Although DHT markedly stimulated LNCaP proliferation, it had no proliferative effect on the DU145 and PC3 cell lines. By contrast, PRL significantly modulated the proliferation of the DU145 and PC3 lines, but exerted weak, if any, effect on the proliferation of the LNCaP cell line. PRL increased the percentage of PC3 proliferating cells (i.e., cells in the S/G2 phases of the cell cycle) at low doses (0.1 mIU/mL) and decreased this percentage at high doses (10 mIU/ml). CONCLUSIONS: Proliferation of androgen-insensitive human prostate cell lines can be significantly modulated by prolactin.

Androgens↗

PubMed1996

The use of the decision tree technique and image cytometry to characterize aggressiveness in World Health Organization (WHO) grade II superficial transitional cell carcinomas of the bladder.

The aggressiveness of human bladder tumours can be assessed by means of various classification systems, including the one proposed by the World Health Organization (WHO). According to the WHO classification, three levels of malignancy are identified as grades I (low), II (intermediate), and III (high). This classification system operates satisfactorily for two of the three grades in forecasting clinical progression, most grade I tumours being associated with good prognoses and most grade III with bad. In contrast, the grade II group is very heterogeneous in terms of their clinical behaviour. The present study used two computer-assisted methods to investigate whether it is possible to sub-classify grade II tumours: computer-assisted microscope analysis (image cytometry) of Feulgen-stained nuclei and the Decision Tree Technique. This latter technique belongs to the Supervised Learning Algorithm and enables an objective assessment to be made of the diagnostic value associated with a given parameter. The combined use of these two methods in a series of 292 superficial transitional cell carcinomas shows that it is possible to identify one subgroup of grade II tumours which behave clinically like grade I tumours and a second subgroup which behaves clinically like grade III tumours. Of the nine ploidy-related parameters computed by means of image cytometry [the DNA index (DI), DNA histogram type (DHT), and the percentages of diploid, hyperdiploid, triploid, hypertriploid, tetraploid, hypertetraploid, and polyploid cell nuclei], it was the percentage of hyperdiploid and hypertetraploid cell nuclei which enabled identification, rather than conventional parameters such as the DI or the DHT.

Adult↗

PubMed1996

Differential histochemical peanut agglutinin stain in benign and malignant human prostate tumors: relationship with prostatic specific antigen immunostain and nuclear DNA content.

The histochemical binding pattern of the peanut (Arachis hypogaea) lectin (PNA) was quantitatively described by means of computer-assisted microscope analysis in 28 benign prostatic hyperplasias (BPH), 15 prostatic intraepithelial neoplasias (PIN), and 119 prostatic adenocarcinomas. PNA exhibits nonimmune but selective binding to glycoproteins with beta-D-galactosyl(1,3)-N-acetyl-D-galactosamine residues. We also investigated whether a relationship existed between the number of histochemical-related PNA acceptors and the histochemical prostate-specific antigen (PSA) stain intensity, and between the number of PNA receptors and DNA ploidy level. The results show that neoplastic prostate tissues and high-grade intraepithelial prostatic neoplasias (PIN2_3) exhibit a significantly higher number of PNA acceptors than benign prostatic hyperplasias and low (PIN1) grade prostatic intraepithelial neoplasias. A statistically significant correlation was observed between the number of histochemically related PNA acceptors and PSA immunostain intensity. Lastly, diploid prostatic tumors, whether benign or malignant, exhibited a significantly higher number of PNA acceptors than aneuploid ones. These results suggest that PNA acceptors play an important role in the biology of prostate tumors.

Adenocarcinoma↗

PubMed1996

Image cytometry analysis of Feulgen-stained nuclei in 72 lipomatous lesions including atypical lipomas and well-differentiated liposarcomas.

Well-differentiated lipomatous tumors constitute a histopathologic category whose nomenclature has been controversial, particularly with respect to the distinction between atypical lipomas of the extremities and well-differentiated liposarcomas of the retroperitoneum. To determine whether there were differences in image analytic parameters between these neoplasms, 72 lesions including 21 typical lipomas, 7 atypical lipomas, 16 retroperitoneal and 5 nonretroperitoneal well-differentiated, 9 dedifferentiated, and 14 pleomorphic liposarcomas were submitted to the computer-assisted microscopic analysis of Feulgen-stained nuclei. This methodology enabled four groups of variables to be calculated. These included: (1) quantitative chromatin pattern description (14 variables); (2) the measurement of proliferative activity (1 variable); (3) nuclear DNA content (DNA ploidy level, 5 variables); and (4) the measurement of cell density and topographical cell nuclei organization (2 variables). The results strongly suggest that atypical lipomas, whether superficial or deep, and well-differentiated liposarcomas, whether retroperitoneal or not, belong to the same category in terms of the variables analyzed.

Adult↗

PubMed1996

The additional predictive value contributed by quantitative chromatin pattern description as compared to DNA ploidy level measurement in 257 superficial bladder transitional cell carcinomas.

The results of quantitative chromatin pattern description were compared with the determination of the DNA ploidy level, and the histological grading and clinical staging of superficial transitional cell carcinomas (sTCCs) of the bladder. We investigated whether this quantitative description adds useful information to the one obtained by the other methods used for predicting the biological behavior of sTCCs. The quantitative chromatin pattern description was carried out by means of the digital cell image analysis of Feulgen-stained nuclei in a series of 257 sTCCs. The results show that according to the clinical sequence "remission (134 patients) --> stable recurrence (101 patients) --> progression (13 patients) --> death (9 patients)', quantitative chromatin pattern description shows that certain areas of the nucleus undergo a continual process of condensation and that the distribution and spread of the chromatin becomes more and more heterogeneous. This is accompanied by a more frequent appearance of pale areas in the nucleus and an increase in nuclear size. Of the 257 sTCC patients, 148 had pTa/PpT1 grade I or III tumors. Of these 148, histological grading and clinical staging made it possible to correctly predict the biological behavior of the tumors of 120/148 (81%). DNA ploidy level determination increased this correct prediction from 81 to 84%. When the information contributed by quantitative chromatin pattern description was added to that contributed by the combination of histological grading, clinical staging and DNA ploidy level determination, the prediction level was 93%.

Adult↗

PubMed1996

[Intra-cavernous collagen analysis in impotence].

The role of the different components of the corpus cavernosum is very important in the physiopathology of erectile dysfunction. The precise function of collagen fibers in erectile physiology is controversial. We measured the different types of collagen (I, III, IV) in the corpus cavernosum of 26 impotent and potent men using cell image analysis and immunohistochemistry. We found differences in the distribution of collagen I, III, IV in each pathological group (arterial, caverno-venous, psychogenic). The augmentation of collagen I and the light diminution in collagen III makes the corpus cavernosum less compliant which translates clinically as an alteration in the filling of the vascular spaces and by dysfunction of the veno-occlusive mechanism. The diminution in collagen IV shows an alteration in the function of endothelial cells. The fact that in the psychogenic group we found also a diminution in collagen IV content, makes us infer that psychogenic impotence could be the first stage of an organic impotence.

Adult↗

PubMed1996

The value of nuclear DNA and texture analysis by digital image processing in the diagnosis of lipomatous and leiomyomatous tumours.

The present study investigates whether the quantitative chromatin pattern description carried out by means of the digital cell image analysis of Feulgen-stained nuclei can contribute valuable diagnostic information on sarcomas. A series of 77 soft tissue tumours was consequently studied. This series included 9 benign lipomas versus 26 malignant liposarcomas and 26 benign leiomyomas versus 16 malignant leiomyosarcomas. Of the 26 liposarcomas, 14 were primary and 12 recurrent tumours. Of the 16 leiomyosarcomas, 13 were primary and three recurrent tumours. The results show that the combined use of principal-components analysis and the discriminant analyses of digital data obtained by means of the computer-assisted microscope analysis of Feulgen-stained nuclei made it possible to obtain a clear-cut distinction between the three histopathological groups relating to the lipoma/liposarcoma group of soft tumours. In contrast, while a clear-cut distinction could be made between the recurrent leiomyosarcomas and the primary leiomyosarcomas, such a distinction was not possible between the benign leiomyomas and the malignant primary leiomyosarcomas. This feature, along with previous ones obtained through DNA ploidy level determination, suggests to us that leiomyomas, or at least some of them, are in the process of malignant transformation. In other words, leiomyomas might be the pre-malignant counterpart of leiomyosarcomas, a feature that the present results do not suggest for lipomas versus liposarcomas.

Adult↗

PubMed1996

The computer-assisted microscope analysis of Feulgen-stained nuclei linked to a supervised learning algorithm as an aid to prognosis assessment in invasive transitional bladder cell carcinomas.

The aim of the present work is to ascertain whether additional information to grading and staging can be obtained for the prognosis of invasive bladder tumours (T2, T3, T4) by means of two computer-assisted methodologies. The first methodology relates to the digital image analysis of Feulgen-stained nuclei and the second to a supervised learning algorithm named Decision Tree. The digital image analysis of Feulgen-stained nuclei generated 11 variables for nuclear DNA content and 15 for quantitatively describing chromatin pattern. These 26 variables were submitted to a Decision Tree technique which produces multi-attribute logical classification rules by selecting informative variables and determining discriminatory values for each of them. A series of 41 patients for which the majority of the T2 bladder tumours (68%) were associated with a 'good' prognosis (remission) while the majority of the T3-T4 ones (77%) were associated with a 'bad' one (clinical progression or death) were submitted to the proposed approach. The results show that the decision tree was able to characterise the tumours associated with a 'bad' prognosis in the T2 sub-group (32%) and the tumours associated with a 'good' prognosis in the T3-T4 one (23%), by using only few image-generated variables (added to the clinical stage).

Adult↗

PubMed1996

Quantitative measurements of desmin and vimentin immunostains and cell density in leiomyomas and leiomyosarcomas.

The distinction between benign and malignant smooth muscle tumours relying on histological features such as the mitotic index and pleomorphism remains a generally acknowledged difficulty in modern pathology. A cell image processor was therefore used to quantitatively assess the desmin and vimentin immunostain in 39 smooth muscle tumours which included 26 benign (leiomyomas) and 13 malignant (leiomyosarcomas) cases. The 13 leiomyosarcomas were primary (non-recurrent and non-metastatic). Ploidy level and cell density were also assessed on each of these 39 tumours by means of the computer-assisted microscopic analysis of 5-microns thick Feulgen-stained histological sections. The results show that while neither the ploidy level determination nor the quantitative assessment of the vimentin immunostain made it possible to distinguish between leiomyomas and leiomyosarcomas, cell density determination and the quantitative assessment of the desmin immunostain enabled such a distinction to be made. Indeed, the leiomyomas exhibited a much higher level of desmin positivity than the leiomyosarcomas, as did diploid tumours as compared to the aneuploid (benign or malignant) ones. Furthermore, the leiomyoma group exhibited a significantly lower mean cell density value than the leiomyosarcoma group. The present study further confirms the lack of relationship between ploidy level and cytological malignancy in smooth muscle tumours.

Adolescent↗

PubMed1996

Does any correlation exist between the Gleason classification system and the computer-assisted microscope analysis of Feulgen-stained nuclei features in human prostate adenocarcinoma?

Grading prostatic adenocarcinomas remains an important problem. Various systems exist (including those proposed by Gleason) but none of these systems seems able to reliably predict either the lethal potential of a tumor in an individual patient or the responsiveness of an individual tumor to various forms of therapy. The most frequently used grading system, as proposed by Gleason, is essentially based on the description of tumor growth pattern. The aim of the present work is therefore to investigate whether the quantitative description of morphonuclear features (including cell anaplasia) and the DNA ploidy level can contribute significant information to the Gleason grading, thus partly at least reducing its subjective nature. This quantitative description was carried out by means of the Feulgen-stained nuclei image cytometry computation of 24 variables in 101 prostatic adenocarcinomas. The results show that both DNA ploidy- and morphonuclear-related variables were weak discriminators for the various grades of the Gleason classification system, and particularly between the high (Gleason 4 and 5) and the other Gleason-grades, i.e. the low (Gleason 1 and 2) and intermediate (Gleason 3) ones. The morphonuclear evidence of anaplasia is thus not redundant data on tumor growth pattern and may be expected to provide additional diagnostic information.

Adenocarcinoma↗

PubMed1995

The use of digital image analysis of chromatin texture in Feulgen-stained nuclei to predict recurrence of low grade superficial transitional cell carcinoma of the bladder.

BACKGROUND: Identifying a marker enabling prediction of recurrence in the group of superficial transitional cell carcinomas (sTCCs) of the bladder remains an important challenge today. This report quantitatively describes chromatin patterns with respect to such sTCC recurrence. MATERIALS AND METHODS: Twenty-nine patients with sTCCs who did not exhibit tumor recurrence within a minimum of 24 months were compared with 21 patients with sTCCs who exhibited tumor recurrence two or three times in a 24-month period, for a total of 74 sTCCs. Quantitative chromatin pattern description was performed by the digital cell image analyses of Feulgen-stained nuclei. Six morphonuclear parameters were thus described and subsequently used to determine a score, allowing biological behavior of sTCCs to be described, i.e., recurrence versus non-recurrence in one calculation step. DNA ploidy level was also determined in each sTCC by assessing its DNA histogram type. RESULTS: Of 32 patients with Grade 1 pathologically classified pTa/pT1 tumors, DNA ploidy level determination permitted correct prediction of tumor nonrecurrence or recurrence of 13 (41%), whereas determination of the score values enabled prediction of nonrecurrence or recurrence of 25 (78%). Combining DNA ploidy level data and the score values enabled recurrence or nonrecurrence to be predicted for 29/32 of the patients (91%). CONCLUSIONS: The quantitative description of chromatin patterns by digital cell image analysis of Feulgen-stained nuclei can provide helpful information, in addition to DNA ploidy level determination, in predicting tumor recurrence of low grade superficial transitional cell carcinomas of the bladder.

Carcinoma, Transitional Cell↗

PubMed1995

Influence of dihydrotestosterone, epidermal growth factor, and basic fibroblast growth factor on the cell kinetics of the PC3, DU145, and LNCaP prostatic cancer cell lines: relationship with DNA ploidy level.

The cell kinetics (percentage of cells in the S+G2 phases of the cell cycle) and the DNA ploidy levels (nuclear DNA content) were determined in 108 samples each of the PC3, DU145, and LNCaP prostate cancer models. This was carried out by means of the digital cell image analysis of Feulgen-stained nuclei. Two to three hundred cell nuclei were analyzed for each of the 324 samples under study. The three cell lines were submitted to experimental conditions including the addition of dihydrotestosterone (DHT), epidermal growth factor (EGF), and basic fibroblast growth factor (bFGF), either alone or in combination, to the culture media. The results show that under the present culture conditions, the PC3 cell line was DHT-, EGF- and bFGF-insensitive. In contrast to what is generally reported in the literature, the DU145 cell line was DHT- and EGF-sensitive under the present culture conditions, but bFGF-insensitive. The LNCaP cell line was DHT-sensitive, but EGF- and bFGF-insensitive. While mainly tetraploid, the three cell lines nevertheless exhibited a significant level of heterogeneity in their nuclear DNA content distributions. Indeed, the proportions of non-tetraploid (diploid, hyperdiploid, triploid, hypertriploid, hypertetraploid, polymorphic) DNA histograms were 14% in the PC3, 16% in the DU145, and 29% in the LNCaP cell lines. These results suggest that the DNA ploidy level would not influence the hormone sensitivity level in the cell lines since they had significantly distinct hormone sensitivity profiles while remaining mainly tetraploid.

Cell Division↗

PubMed1995

Image cytometry determination of ploidy level, proliferative activity, and nuclear size in a series of 314 transitional bladder cell carcinomas.

Image cytometry was carried out on 281 superficial (Ta and T1) and 33 invasive (T2 to T4) bladder cancers. The parameters used to characterize these bladder tumors were: (1) histopathological grading, (2) clinical staging, (3) tumor size, (4) deoxyribonucleic acid (DNA) index (DI), (5) DNA histogram type (DHT), (6) percentage of euploid (diploid plus tetraploid) cells, (7) percentage of polyploid cells (> 5C DNA content), (8) proliferative activity (S phase fraction value), and (9) nuclear area (NA). The proliferative activity of the tumors was not related to either histopathological grade or to clinical stage, but it was related to the DHT parameter, which made it possible to identify diploid, hyperdiploid, triploid, hypertriploid, tetraploid, and polymorphic tumors. The hypertriploid tumors exhibited a significantly lower proliferative activity than the nonhypertriploid ones. Although both the DI and the NA values correlated significantly with histopathological grading, only the NA values correlated significantly with clinical staging. We further observed that some grade III bladder tumors were definitely diploid, whereas some grade I tumors were highly aneuploid. We thus hypothesize that the ploidy level of a given tumor reflects its age directly and its aggressiveness only very indirectly. In our opinion aneuploidy is only an indirect marker of aggressiveness because it reflects the fact that a malignant tumor is old, ie, has been present in a patient over a long period of time and has had ample time to express its malignancy at the clinical level. A significant relationship was accordingly obtained between tumor size and ploidy level with the highest proportion of aneuploid tumors and the highest percentage of polyploid cell nuclei being observed among the largest bladder tumors.

Adult↗

PubMed1995

Lymphangiosarcoma. Reports of 3 cases and review of the literature.

Three cases of lymphangiosarcoma have been followed recently. All were finally treated by amputation. Only one is actually disease-free. The other two developed local recurrence at the thoracic cage. An extensive review of the literature follows the case presentation.

Combined Modality Therapy↗