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A Moragas

Publications and source records attributed to A Moragas.

At least 19 recordsLinked to original sources
PubMed1999

[Gastrointestinal stromal tumors: prognostic value of DNA analysis with flow cytometry and of classical clinicopathologic parameters].

BACKGROUND: Biological behavior of gastrointestinal stromal tumours (GIST) is still difficult to predict. The aim of this study was to analyze the prognostic valve of DNA study by flow cytometry in addition to the classical clinicopathologic parameters. PATIENTS AND METHODS: 82 GIST were investigated to assess by multivariable analysis the prognostic significance of classical morphologic and clinical features and DNA flow-cytometric analysis. RESULTS: Features significantly correlated with bad prognosis were: pain, recurrences, metastasis, small intestine tumours, invasion of adjacent tissues, size > 6 cm, infiltrative pattern, high cellularity, high-grade of atypia, mitosis count > 2/50 high powered field, necrosis, DNA aneuploid-hyperploid or near-diploid, S and SG2M-phase of aneuploid/s population/s > 11% and average S-phase > 11%. Multivariable analysis showed that mitotic activity was the only independent variable indicating poor prognosis. CONCLUSIONS: In this series of GIST mitosis count was the only independent prognostic factor, being more important than flow-cytometric variables like DNA ploidy and cellular cycle values.

Adolescent↗
PubMed1998

Characteristics of perisinusoidal collagenization in liver cirrhosis: computer-assisted quantitative analysis.

OBJECTIVE: To determine the respective roles of septal fibrosis, necroinflammatory activity, iron deposition, steatosis, and patterns of nodular and septal remodeling in the collagenization of the perisinusoidal space in livers from patients undergoing transplantation for alcoholic or posthepatitis C cirrhosis and to ascertain whether perisinusoidal collagenization has clinical implications added to those of septal fibrosis. STUDY DESIGN: Sixty-six hepatectomy specimens from patients undergoing liver transplantation for cirrhosis were analyzed. Thirty-two alcoholic and 34 posthepatitis C cirrhoses were included. Picro Sirius-stained slides were examined with polarized light and the amount of perisinusoidal collagenization measured by computerized image analysis. Size distributions of septa and nodules were assessed by mathematical morphology methods. RESULTS: The septal and perisinusoidal fibrosis indices and Knodell and Pugh-Child scores showed significant differences between alcoholic and posthepatitis cirrhoses. Correlation between septal fibrosis and perisinusoidal collagenization was weak, though significant. Both variables correlated significantly with the clinical score. The correlation was negative between septal fibrosis or perisinusoidal collagenization and the Knodell score. CONCLUSION: Perisinusoidal collagenization was not a feature of all cases of cirrhosis, although it was more prominent in alcoholics. For the whole series, it significantly correlated with the clinical score, which increased significantly when high perisinusoidal collagenization was added to high septal fibrosis. No absolute dependence was found between perisinusoidal collagenization and septal fibrosis; percentage of slender fibrous septa and amount of iron deposition were other factors entered in the regression equation.

Adult↗
PubMed1998

Image analysis of dermal collagen changes during skin aging.

OBJECTIVE: To determine progressive quantitative, directional and textural changes in dermal collagen as a function of age and sex and to estimate their evolutive trend with appropriate regression models. STUDY DESIGN: Ninety-six samples of abdominal skin from autopsy cases were analyzed. The ages ranged from 3.5 months to 86 years. Picro-Sirius-stained slides were examined by polarizing microscopy, and spatial density, directional features and texture of collagen were measured by computerized image analysis. Nonlinear regression models were built to estimate evolutive changes with respect to age. The relationship between spatial orientation of collagen bundles and age was best modeled by linear regression. RESULTS: The evolutive patterns of dermal thickness and spatial density of collagen bundles correspond to a second-order polynomial model with a progressive increase from childhood to middle age and a relatively sharp decrease after the seventh decade. The evolution of textural pattern of dermal collagen, defined by gradient analysis, depicts a sort of inverted U. Its complexity is maximum in the first year of life, decreases until the period 25-50 years and increases progressively after the sixth decade. The horizontal orientation of collagen bundles with intermingled fascicles oriented in other directions, shown by young individuals, is progressively simplified with aging. In elderly subjects, collagen bundles have a horizontal orientation. No significant sex-related differences were found. CONCLUSION: Dermal collagen changes related to aging are apparently independent of sex, at least in abdominal skin, and show characteristic curvilinear evolutive trends defined by decreased dermal thickness in the elderly, decrease in the spatial density of collagen bundles and increase in textural heterogeneity of the dermis. Progressive simplification in the orientation of collagen bundles leading to a predominant horizontal disposition followed a linear trend. These changes could contribute to providing a substantial morphologic basis to age-associated biomechanical alterations in the skin.

Abdomen↗
PubMed1996

Differential diagnosis of malignant and reactive cells from serous effusions: image and texture analysis study.

The interrelationship of textural primitives which define morphological texture can be estimated by quite different descriptors; the discriminant value of which varies considerably. In the present study three different approaches to the texture analysis of nuclear chromatin were assayed to correctly allocate 332 cells from a pool obtained from serous effusions (six malignant mesotheliomas, six reactive mesothelial proliferations and five pleural metastases of lung adenocarcinoma). In all cases, initial cytological diagnosis posed considerable problems and final diagnosis was established by histologic examination of surgical specimens. The three approaches were based on binarization of the image obtained by edge detection, gradient analysis and pattern spectrum by morphological opening-closing, respectively. Characteristics afforded by each method were: (a) spatial distribution of heterochromatin, besides geometric features, (b) features related to transitions and contrast between dark and light chromatin primitives, and (c) granulometric characteristics of the theoretically biphasic heterochromatin-euchromatin image defined by mathematical morphology. The three methods were applied to the raw grey-tone image and did not require interactive handling. Although each of the three approaches yielded relatively satisfactory results, with percentages of well-classified cells in the test set ranging from 61.45 to 67.47, the best results (78.31% of well-classified cells) were obtained taking into consideration the three types of variables (area, 2nd opening, 5th closing, and S.D. of the amplitude image). A point to be stressed is the considerably high proportion of correctly-allocated reactive mesothelial cells (82.0%) in a field where subjective assessment commonly yields rather poor results. Nevertheless, classification yielded 14.8% and 3.3% false positives as adenocarcinomatous and malignant mesothelioma cells, respectively. In the theorectical situation devised in the study, results on a cell-by-cell basis encouraging and suggest that a textural approach might be useful in a dedicated expert system or on a more real case-by-case basis.

Adenocarcinoma↗
PubMed1995

Nuclear texture in poorly differentiated small round cell tumors. Image analysis study of fine needle aspiration material.

Gradient analysis and pattern spectrum decomposition based on mathematical morphology concepts were used to explore nuclear texture patterns in a pool of 108 cells obtained by fine needle aspiration of five undifferentiated small round cell tumors of childhood, including one case each of Wilms' tumor, neuroblastoma, lymphoblastic lymphoma, Ewing's sarcoma and rhabdomyosarcoma. The aim of the study was to determine the presumptive value of nuclear pattern to correctly allocate each isolated cell to each of the five patients. The cells were examples of five histogenetically different tumors, all undifferentiated and with a close microscopic resemblance to one another. High gradient structures (heterochromatin-euchromatin and nuclear membrane edges) were estimated by a difference-of-boxes filter, and pattern spectrum decomposition was obtained by successive openings and closings performed on the input gray tone image. One important feature of these procedures was that no prior selection by thresholding of the structures to be studied was required, thus obviating subjective bias. Percentages of correctly allocated cells by canonical analysis ranged from 70.0% (rhabdomyosarcoma) to 92.9% (Ewing's sarcoma). Although the five cases could be distinguished using seven texture variables, this does not imply generalization of the results for the differential diagnosis of these tumors. Nonetheless, the possibility that undifferentiated small round cells present distinctive nuclear patterns when studied by sensitive image analysis techniques is suggested by our results.

Biopsy, Needle↗
PubMed1994

Image analysis of hemosiderin-laden macrophages in bronchoalveolar lavage fluid.

The aim of this study was to assess quantitatively the relationship between the number of iron-laden macrophages, extent of hemosiderin content and amount of dark-stained hemosiderin clumps in bronchoalveolar lavage (BAL) fluids. The series included specimens from 20 subjects whose BAL had yielded iron-laden macrophages. Six had developed hemoptysis 3-15 days prior to BAL. Quantitative studies were performed on smears stained by the ferrocyanide reaction, using true color image analysis for image segmentation. A top-hat function based on mathematical morphologic concepts was used for extraction of dark clumps of hemosiderin. The results demonstrated the presence of iron-laden macrophages three days after hemoptysis. There was a moderate correlation between the percentage of macrophages and amount of hemosiderin content, but the extent of dark-stained clumps did not increase in parallel to the increase in hemosiderin content and probably represented an advanced stage in the phagocytic processing of hemosiderin formed from engulfed red blood cells. The main difference between subjects with and without previous hemoptysis was higher values for dark clumps of hemosiderin in the former.

Adult↗
PubMed1993

Mathematical morphologic analysis of aging-related epidermal changes.

Fractographic techniques based on mathematical morphology were used to study aging-related epidermal changes in abdominal skin samples obtained from 96 autopsy cases. Three linear roughness indices were evaluated for the rete peg profile and the shrinkage effect on the basal layer and interface between the granular and horny layers. Elderly subjects had a 36.3% decrease in rete peg-related roughness index when compared with younger subjects. This roughness index has been corrected, with shrinkage due to skin elasticity taken into account. For females, fitting of a logistic decay function yielded a curve with right and left asymptotes and a steeper descent between 40 and 60 years. Half value time--i.e., the time when half rete peg profile flattening occurred--was 46.8 years. In contrast, males showed almost monotonical decay. Epidermal thickness measured between rete pegs showed the same exponential decline for both sexes, with values from 22.6 to 11.4 microns. Skin shrinkage in elderly subjects decreased 22% in superficial layers and only 6% in the lower epidermis. In both cases shrinkage had a linear relation with age, and no sex differences were found.

Adolescent↗
PubMed1993

Mathematical morphologic analysis of the aortic medial structure. Biomechanical implications.

The architecture of the aortic tunica media was studied in 55 autopsy specimens (26 normotensive and 29 hypertensive patients). The purpose of the study was to elucidate whether, as commonly stated, homogeneous disposition of concentric lamellar units could be substantiated or whether an architectural gradient reflecting the decreasing biomechanical gradient in the circumferential stress, concentrated towards the inner wall, was present. The elastin lamellae thickness, interlamellar distance, fibrosis index and fragmentation index were quantitated by mathematical morphology methods. The results did not support classic histologic descriptions but showed that lamellar units were significantly thicker in the inner than in the outer zones of the media--i.e., a morphologic gradient was present. The differences between inner and outer zones were more marked in hypertensive patients than in controls. The fibrosis index increased with age, especially in hypertensive patients. The fragmentation index in hypertensive patients was significantly higher than in controls and more marked in abdominal than in thoracic aorta. This weakening in the biomechanical resistance of elastin fibers could be one of the factors explaining the predominance of aneurysms in the abdominal aorta.

Adult↗
PubMed1993

Textural analysis of lymphoid cells in serous effusions. A mathematical morphologic approach.

Nuclear texture of reactive and well-differentiated neoplastic lymphocytes from serous effusions was studied by an approach based on principles of mathematical morphology. Density features were obtained before and after gray level nuclear image transformation by morphologic closing (dilation followed by erosion) and application of a top-hat function, which detects light or dense spots with a determined width and contrast. Five cases of benign reactive lymphocytic serous effusions and 11 cases of effusions in well-differentiated lymphocytic lymphomas were analyzed retrospectively. Each lymphoid cell was characterized by 24 densitometric features. Rank-order transformation was used for linear discriminant analysis given non-normal distributions of variables. In a first model formed by pooling all cells, discriminant function distinguished between 110 reactive and 216 malignant lymphocytes in the learning set and between 111 reactive and 226 malignant lymphocytes in the test set with better than 81% accuracy in both. In a second model, correct classification of cases as reactive or malignant was achieved in 5/5 reactive and 11/11 malignant lymphoid effusions. The results indicate that mathematical morphologic transformations of the gray level image may be an effective adjunct to other textural descriptors of cellular atypia, especially in the differential diagnosis of lymphoid serous effusions.

Ascitic Fluid↗
PubMed1993

Fine needle aspiration diagnosis of renal oncocytoma. A mathematical morphologic approach.

Differentiation between renal oncocytomas and well-differentiated oxyphilic cell renal carcinomas from fine needle aspiration cytology smears may present considerable difficulties. To better define diagnostic criteria, we used high-resolution architectural characteristics of nucleus and cytoplasm based on mathematical morphologic concepts. Particulate structural elements were selected for their size and optical density by the so-called top-hat function. Spatial density, size distribution and a function of distance between particles were computed. We quantitated cellular samples from fine needle aspirates obtained from 10 renal oncocytomas and 5 well-differentiated oxyphilic cell renal carcinomas. In two of the former, cytologic diagnosis was doubtful. Subsequent removal of the tumor and its histologic examination established the final diagnosis in all cases. Stepwise discriminant analysis correctly classified all cases as oncocytomas or renal carcinomas, although the results need to be considered with caution due to the necessarily limited number of observations. Multivariate graphic representation by star glyphs clearly depicted the differences between oncocytoma and oxyphilic cell renal carcinomas and the abnormal characteristics of two oncocytoma cases misclassified initially.

Adenoma↗
PubMed1992

Cirrhotic changes in livers from children undergoing transplantation. Image analysis.

The pattern and extent of disorganization of the liver architecture were studied in 25 children undergoing orthotopic liver transplantation for cirrhosis. Image analysis techniques based on mathematical morphology were used to define seven parameters for each case, including fibrosis index (percentage of Sirius-red-stained areas), three categories of regenerative nodules (< 0.8, 0.8-1.6 and > 1.6 mm in diameter) and three categories of fibrous septa (< 0.4, 0.4-1.2 and > 1.2 mm in width). Fibrosis index ranged from 10.2% to 51.9%. Percentage of small nodules of infralobular size (< 0.8 mm in diameter) varied from 31.4% to 98.2%. Percentage of large nodules, > 1.6 mm in diameter, in only four cases was > 15%. Multivariate clustering analysis classified the cases into three main groups. One of them included only cases of cirrhosis secondary to parenchymal disease or to inborn errors of metabolism. In their pattern, tiny nodules predominated, and the percentage of slender septa, < 0.4 mm in diameter, was very high, although the overall fibrosis index was relatively low. Patients with biliary cirrhosis were classified into two groups. In one the fibrosis index was low and the size of the nodules variable, with 12% large nodules. In the other the fibrosis index was high, and small nodules, < 0.8 mm in diameter, predominated. No relationship was found with age at transplantation or previous portoenterostomy. A presumptive explanation for this divergent evolution might be the occurrence of cholangitic episodes. Overall fibrosis that the liver can sustain without failure is apparently limited.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1992

Mathematical morphologic analysis of liver cirrhosis. Correlation with etiology, clinical score and hepatocellular carcinoma.

Remodeling of the cirrhotic liver was studied retrospectively by mathematical morphologic methods in 75 autopsy cases (40 alcoholic, 17 hepatitis B virus (HBV)-related and 18 cryptogenetic cirrhosis), including 28 hepatocellular carcinomas. The aim was to obtain objective measurements of cirrhotic patterns that could be correlated with liver function evaluated by the Pugh-Child score, establish the relationship among different morphogenetic features and evaluate the implications of an objective classification of cases by numerical taxonomy in terms of their etiology, liver function and malignant transformation. The results indicate that the Pugh-Child score was closely related to the global amount of fibrosis or to the percentage of regenerative nodules < 0.8 mm in diameter. In contrast, the higher the percentage of lobular-sized regenerative nodules (0.8-1.6 mm), the better the functional score, suggesting that they are probably residual lobules, albeit completely surrounded by fibrous tissue, rather than true regenerative pseudolobules. The four groups of cases obtained by numerical taxonomy (cluster analysis) showed different distributions for alcoholic and HBV-related cirrhosis. The pattern of the latter was practically analogous to that in classically labeled cryptogenetic cirrhosis, suggesting its viral etiology. Taxonomic classification had functional implications. The Pugh-Child score showed a definite relationship with the different clusters obtained. The incidence of malignant transformation gradually decreased from group G1 to G4, with a steeper descent between G2 and G3. These results might contribute to a more dynamic concept of morphologic changes in liver biopsies from patients with cirrhosis.

Adult↗
PubMed1990

[MALT lymphoma].

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B-Lymphocytes↗
PubMed1990

Morphometric analysis of myocardial bridges in children with ventricular hypertrophy.

The nuclear cross-sectional area of the muscular fibers from a series of myocardial bridges was analyzed and compared to both the adjacent and underlying myocardial fibers. The series came from 12 hearts of children, ranging in age from 24 h to 2 years, with diverse forms of congenital heart disease, which caused left ventricular hypertrophy and had a myocardial bridge in the path of the anterior interventricular coronary artery. The cross-sectional areas of myocardial nuclei were measured for the bridging myocardial fibers, the adjacent myocardium, and the myocardial fibers underlying the bridged coronary artery. A significant statistical difference between the bridging muscular fibers and those underlying the submerged artery was observed, as well as between the bridging fibers and its adjacent ones. This findings suggests that myocardial bridges not only represent an anatomical abnormality, but probably imply different functional behavior as well.

Cardiomegaly↗
PubMed1989

Lymphadenopathy in HIV infection: histological classification and staging.

The histological alterations seen in HIV-related lymphadenopathy have been described with different terms by different authors. In order to facilitate comparisons of results from various laboratories, a group of pathologists of the European Lymphoma Study Group (later the European Association for Haematopathology) have proposed a histological classification for the evaluation of HIV related lymphadenopathy. Most observers agree that the morphological and immunohistochemical alterations in the follicles (germinal centres) are the most conspicuous and earliest changes seen. The follicular alterations were therefore used as the basis for the proposed classification. In addition, some features occasionally seen were also included, i.e. angioimmunoblastic hyperplasia, multicentric Castleman-like lesions, and vascular lesions, especially pretumorous and tumorous stages of Kaposi's sarcoma. The proposed classification was used by the members of the group of a collection of lymph nodes compiled from the various centres. The classification was shown to be reproducible and to have clinical relevance in staging of the patients. The prognostic relevance as to the survival of the patients has to be further substantiated by follow-up studies. The proposed classification offers a common terminology for the alterations previously described by different terms by various authors.

AIDS-Related Complex↗