PubMed Health⌕ Search

Biomedical subjects

G M Mariuzzi

Publications and source records attributed to G M Mariuzzi.

At least 55 records · Page 3Linked to original sources
PubMed1986

Quantitative microscopy and index formulation in continuous pathologic lesions.

Quantitative microscopy is a general term that includes methods and techniques for quantifying normal and pathologic cellular and tissue processes. At present, morphometry is a popular term that is used loosely to denote several aspects of quantification in histopathology and cytopathology. Multivariate analysis, that is, the recognition of patterns, should be associated with quantitative microscopy. When we use this technique, the computer allows us to overcome the problems of feature value overlap between diagnostic groups and of the diagnostic variation in the subjective evaluation. In index formulation, a single number expresses the degree of modification of continuous lesions. Examples are drawn from preneoplastic lesions and kidney pathology. The former group includes indices for the proliferative disorder, the differentiative defect and the malignancy progression of the uterine cervix as well as the index of DNA status of the urothelial papillary carcinoma. The latter group includes the evaluation of the matrix increase in the diabetic glomerulosclerosis. Quantitation of histochemistry and immunohistochemistry can be performed. A good example is the kidney immunofluorescence, whose positivity is expressed by an index. The theoretical background of pathologists represents the basis in which quantitative microscopy and related analyses are rooted.

Humans↗
PubMed1986

Quantitative evaluation of the progressive nuclear abnormalities in urothelial papillary lesions.

The natural history of noninvasive urothelial papillary carcinomas is characterized by structural and nuclear abnormalities of the epithelial lining in the three grades. Morphometry is applied to measure nuclear-related quantitative parameters from the lower (L) and upper (U) halves of urothelial thickness, i.e. perimeter, area and roundness factor. Their mean and SD as well as the derived parameters have values steadily higher from normal-looking urothelium to G3, whereas the relative frequency distribution shows over-lapping among the grades. The multivariate analysis is then applied. First of all the smallest number of least correlated and most discriminant features is selected: SD of nuclear area log (L), percentage of round nuclei (L), mean of the 10 largest values of nuclear area (L) and mean nuclear perimeter (L). The results of the pattern recognition analysis based on these features show the following percentages of agreement between histopathological and computer classifications: 94% in the training set and 80% in the test set. The calculation of the classification probability and the adoption of a threshold approach of 0.25 less than P less than 0.75 are helpful in identifying the 'in-between' cases, i.e., those in the 'intermediate' position between G1 and G2 and between G2 and G3. Morphometry and multivariate analysis allow us to quantify the nuclear abnormalities of urothelial papillary carcinomas and show a progressive and continuous spectrum of modifications.

Cell Nucleus↗
PubMed1986

Observer variation in interactive computerized morphometry.

The validity of a test system in morphometric histopathology depends on the variation sources involved. Biological variation is one of the variation sources, but is also the object to be studied with morphometry. We studied the variation sources in interactive computerized morphometry in two test systems involving two different commercially available image analyzers. The measurements were made on nuclei in a microscopic field of 5 transitional cell tumors (papilloma and WHO grade I-III carcinomas) of the urinary bladder. It turned out that different observers selected a variable number of nuclei for measurements, the coefficient of variation (CV) in the number of nuclei being 11-11.5%. Mean CV in nuclear perimeter measurements was 4.4-4.8%, and in nuclear area measurements 8.2-8.6%. The variation in measurements by 1 observer was smaller, the CV values being 2.8% for the number of nuclei, 1.2% for nuclear perimeter, and 2.4% for nuclear area. The results showed that interobserver variation can be considerable in these systems. It is suggested that special sampling rules should be tested with the idea of finding the relevant approach with the smallest interobserver variation.

Carcinoma, Transitional Cell↗
PubMed1986

Morphometric and topologic analysis of freeze-fractured interphase nuclei.

Interphase rat liver nuclei were studied by freeze fracturing followed by electron microscopic observations. This method permits information on the native organization of the nuclear components in the hydrated state to be obtained. Morphometric analyses, performed with a Leitz Texture Analysis System, gave precise information on the different nuclear components, based on the histograms of their size distribution in heterochromatin, interchromatin and nucleolar areas. The textural characteristics were analyzed by computer to determine the topologic distribution of the solenoid chromatin fibers, the nucleosome filaments and the ribonucleoproteins in the different nuclear domains.

Animals↗
PubMed1984

Histomorphometry and pattern recognition analysis of urothelial papillary lesions.

The authors report the results of the grading of urothelial papillary carcinoma using histomorphometry and pattern recognition analysis. Features concerning nuclear area, the nuclear roundness factor and inclination angle were measured in 38 cases of urothelial papillary carcinomas. The relative frequency distribution showed overlapping among the grades with a reduction in the practical significance of histomorphometry. To overcome this problem, the pattern recognition analysis was applied. It was found that mean nuclear area, mean roundness factor and percentages of round and horizontal nuclei represent the optimal discriminating set of the subsequent steps in the malignant urothelial transformation.

Carcinoma, Papillary↗
PubMed1978

Decrease of alpha-Hasharon globin in beta-thalassaemia.

In time course experiments performed in subjects carrying haemoglobin Hasharon and beta-thalassaemia the synthesis of alphaA-, alphaHasharon-, beta- and gamma-globin has been determined. The alpha-globin molecules synthesized in excess were found to be removed from the red cell cytoplasm (phenomenon characteristic of beta-thalassaemia, described by Bargellesi et al, 1968a); in addition the alphaHasharon-globin molecules were removed at a faster rate than normal alpha-globin. The preferential removal of the mutant alpha-globin explains the reduced level of haemoglobin Hasharon found in subjects carrying the gene for beta-thalassaemia (Alberti et al, 1975). Reductions below normal levels of other haemoglobin variants occurring in the presence of the counterpart-globin thalassaemia are probably determined through a similar mechanism.

Genes↗
PubMed1975

Haemoglobin Hasharon in a north Italian community.

A survey of haemoglobin variants undertakin in an Italian community (Polesine) has revealed the presence of haemoglobin Hasharon (alpha2 47 Asp yields His beta2) in 108 subjects from 40 families. The variant accounted for 30 to 40% of the total haemoglobin. In subjects doubly heterozygous for Hb Hasharon and beta thalassaemia, the proportion was 17 to 19%. Though there was some evidence that the variant was unstable in vitro, there was no obvious haemoglobinopathy in vivo.

Amino Acids↗
PubMedDate not supplied

Human papillomavirus in cervical condylomata. An immunohistochemical study.

Twenty-seven cervical condylomata were studied by morphological and immunohistochemical methods (peroxidase-antiperoxidase technique according to Sternberger, with some modifications). The antiserum was obtained from rabbits immunized by human papillomavirus virions; 37% of condylomata stained positively and the koilocytotic cells showed a dark brown nuclear stain. This technique, not particularly useful for diagnostic purposes, could be employed to obtain better understanding of the natural history of these cervical neoplasias.

Antigens, Viral↗
PubMedDate not supplied

Interactive image analysis in the rectal mucosa of rheumatoid arthritis.

Interactive measurements of 22 quantitative parameters concerning the status and inflammation of the mucosa were taken in the rectal biopsies of patients suffering from Rheumatoid Arthritis, or with mild nonspecific morphological abnormalities (M.N.M.A.) and inflammation of the lamina propria or with Infective Colitis. The results showed that mean and standard deviation values of the rheumatoid patients are generally intermediate between those of control cases and those of M.N.M.A. and Infective Colitis. The variance analysis revealed that significant differences in some of the features exist between the four groups. Stepwise discriminant analysis helped in identifying three parameters that contributed significantly to discriminating 96.30% of the cases: Mucin area/Mucosal area; Number of inflammatory cells in the lower half/Number of inflammatory cells in the upper half of the mucosal thickness; Number of Granulocytes/mm2 of the lamina propria. Of the 27 cases included in the study, only one belonging to the control group was allocated incorrectly by the computer to the Rheumatoid Arthritis category. High correlation coefficients were observed between some of the morphometric, serological and clinical data in the rheumatoid patients. The highest values were between Number of Mononuclear cells/mm2 of lamina propria and C-Reactive Protein (+0.920) as well as between Mucin area/Mucosal area and serum IgM level (-0.950).

Adult↗