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Biomedical subjects

A Pennella

Publications and source records attributed to A Pennella.

30 records · Page 2Linked to original sources
PubMed1992

p53 protein expression in central nervous system neoplasms.

AIMS: To demonstrate, immunohistochemically, p53 protein expression in a selection of central nervous system tumours; to investigate the relation between p53 expression and that of the proliferation related antigen, PCNA. METHODS: Surgical specimens from 86 central nervous system tumours were routinely fixed, paraffin wax embedded, and immunostained with a monoclonal (PAb 1801) and a policlonal antibody (CM1) p53 protein and a monoclonal antibody against PCNA (PC10). Normal brain samples obtained at necropsy and 10 surgically obtained samples of gliotic brain parenchyma were also immunostained. RESULTS: p53 protein expression was observed in 35 of 86 brain tumours, suggesting frequent p53 gene mutation. p53 protein alterations were associated with all grades of malignancy in tumours displaying solely astrocytic differentiation, with the exception of pilocytic astrocytomas. In those showing oligodendroglial or ependymal differentiation they appeared to be restricted almost to only high grade lesions. No p53 immunoreactivity was observed in normal or gliotic brain tissue; p53 altered expression was not related to the percentage of PCNA labelled cells. CONCLUSIONS: The use of sophisticated gene amplification techniques or highly sensitive immunohistochemical methods might be useful in distinguishing between reactive and neoplastic astrocytic lesions, and in the identification of malignant progression in other non-astrocytic glial tumours. Tumours with very similar histogenetic differentiation features might actually be a genetically heterogeneous group with possible different clinical courses.

Antibodies, Monoclonal↗
PubMed1991

[The structural organization of the human myocardium: the interrelation between myocardial fibers and interstitial connective tissue].

The complex tridimensional structure of the human ventricular myocardium has rarely been studied in the past. In the normal heart, in the lapse of time of few weeks of the embryonic life, a radical transformation from a chaotic plexiform organization to a complex tridimensional structure occurs. From then on, the ulterior growth of the myocardial fibres will only be dimensional and quantitative, because the spatial geometry is to be considered definitive. The role of the interstitial connective tissue in following the development of the myocardium, possibly inducing or influencing it, is still unclear. We have performed an histologic study on serial sections of the ventricular mass of 7 human embryos and fetuses, from 5 to 20 weeks of gestational age. The sections have been evaluated for their morphologic characteristics as evidentiated by histochemical (PAS, trichrome, Gomori silver technique) and immunohistochemical (myosin, actin, desmin, myoglobin, vimentin, fibronectin, smooth muscle cell, endothelial factor VIII) stainings. The results show that myocardial growth is mantellar, proceeding from the epicardium toward the endocardium, with progressive structural organization in strata, variably related one to the other depending upon the considered site of the ventricular mass. The interstitium grows in parallel to the myocardial growth, beginning with a thin network surrounding each fibre that progressively in time is transformed in a complexly arranged and more densely packed structure. The collagen fibres appear initially at epicardial level, particularly around the coronary vessels.(ABSTRACT TRUNCATED AT 250 WORDS)

Connective Tissue↗
PubMed1990

Takayasu's arteritis: a case report and discussion of differences in eastern and western cases.

The possibility of a different clinical expression of Takayasu arteritis (TA) in different geographic areas has been discussed in previous reports. However, many aspects of this problem still remain unclear. A very atypical case of TA concerning the early onset and the unusually slow progress of the disease is reported. Referring to anatomicopathological, clinical, and therapeutic prognostic criteria reported in literature from oriental countries, many discrepancies appear evident. This is consistent with the hypothesis of two different clinical varieties of TA and suggests that, both in its prepulseless stage and after its actual recognition, this disease could show a less malignant progress in western countries.

Arteries↗
PubMed1990

[Nuclear morphometry and estrogen receptors in infiltrating ductal carcinoma of the breast].

In this study ten cases of breast infiltrating ductal carcinoma have been considered. In all of them the content of ER has been evaluated by using monoclonal antibodies. Five of them were ER positive and five were ER negative. For the morphometric study ten nuclei of each case have been considered. By using the S.A.M. (Shape Analytical Morphometry) work-station an analytical study of the nuclear shape was performed. The first step was the extraction of fundamental shape which describes the basic shape of original contour without its irregularities. It was obtained by using two parametric equations. The second step was the evaluation of shape asymmetry by S.A.E. (Shape Asymmetry Evaluator). Finally the contour irregularities were evaluated by Fourier analysis. Along with analytical parameters, dimensions (area, perimeter and maximum diameter) were considered too. All obtained data were submitted to univariate statistical analysis (Student's T test) to compare the two groups (ER positive and ER negative tumors). Area, perimeter and maximum diameter were significatively greater in ER negative cases while analytical parameters were not discriminant between the two groups.

Breast Neoplasms↗
PubMed1989

Hand-mirror (HM) cells in acute lymphoblastic leukaemia (A.L.L.). An attempt at cellular classification by morphometric analytical parameters using the S.A.M. (Shape Analytical Morphometry) system.

A morphometric study of the nuclear and cytoplasmic shape of a blastic population in a case of HM-A.L.L. was performed by comparing the two differently shaped populations with and without HM configuration. The results obtained using analytical size-independent parameters created by the S.A.M. work-station enable us to characterize the shape of both blastic cell populations quantitatively, and strongly suggest the existence of shape modulation from one cellular type toward the other. Thus a possible sequence from blastic cells (having regular, rather round nuclei) to HM cells (characterized by high distortion of both nucleus and cytoplasm) was proposed.

Cell Nucleus↗
PubMed1989

Non-Hodgkin's lymphoma diagnosis aided by the S.A.M. system.

In the attempt to discriminate between centroblasts and immunoblasts, an analytical morphometrical procedure was adopted, considering the nuclei of a randomly selected centroblastic and immunoblastic population from non-Hodgkin's lymphomas and the nucleoli of a more restricted number of the same neoplastic population. All the size-independent shape-descriptor parameters extracted for each step of the mathematical analyses used were submitted to Hotelling's multivariate discriminant analysis that enabled us to achieve a good distinction (3% error) between centroblasts and immunoblasts when nuclear and nucleolar parameters were used together.

Cell Nucleus↗
PubMed1989

Differential diagnosis between thyroid follicular adenoma and carcinoma. Analytic morphometric approach.

In this study some nuclear dimensional and analytical parameters were evaluated in order to distinguish follicular atypical adenoma from follicular carcinoma of the thyroid. Eighty nuclei from carcinomas, 80 from adenomas and 80 from normal thyroid were studied. Analytical parameters obtained by the nuclear shape study (by S.A.M. system) as well as dimensional parameters were submitted to univariate statistical analysis. On the ground of our results atypical adenoma could be considered as an intermediate aspect of a progressive change from benign to malignant even if they are closer to normal thyroid than to carcinoma.

Adenocarcinoma↗
PubMed1989

Is adipose tissue a normal component of the myocardium?

We performed a histological comparative study between endomyocardial biopsies taken from 138 patients with various cardiac pathologies and from 42 autoptic hearts (all negative for right ventricular dysplasia), measuring the amount of adipose tissue in isolation or associated with fibrous tissue. In the clinical cases these features were present in 24 instances on the right and in one on the left side of the ventricular septum, to an extent of more than 20% of the section in six patients, clinically positive for right ventricular dysplasia. On autoptic biopsy, fibro-adipose tissue was found in seven hearts, with different distribution on both ventricles, but to a maximum amount of 20% of the section. The right side of the ventricular septum was affected in five instances. Therefore in our material there is a quantitative difference on right ventricular biopsy with respect to fibro-adipose tissue in normal hearts and in cases with right ventricular dysplasia.

Adipose Tissue↗
PubMedDate not supplied

[Mixed carcinoid-adenocarcinoma tumor of the appendix: a case report and diagnostic and therapeutic considerations].

The layout of the work has stayed motivated from the recent observation of mixed carcinoid, located to the appendix and wide to the peritoneal cable, joint to our observation in an elderly patient with aspecific demonstration clinical-symptomatologic. The study of the endocrine tumors is in continuous evolution also if, to the actual state, there is a better comprehension of this neoplasm, variegated and complex and, under some appearances, still not known well. Jejunoileal carcinoid tumors differ, under many appearances, from those occurring in other sites of the gut. They have relatively high rate of transmural invasion and aggressive clinical behavior, contrasted by a scarce objectivity; the demonstration of symptoms generally implicates the presence of an illness in advanced stage. Also pharmacological therapy made important progress, with the possibility of administer composed able to interfere with the development and the neoplastic growth.

Adenocarcinoma↗
PubMedDate not supplied

Nuclear shape and axillary metastases in breast cancer. Analytic morphometry of aspiration smears.

The aim of this work was to seek quantitative parameters other than dimensions to describe nuclear shape and, by this means, to determine the sum of contour irregularities and large asymmetries and seek a connection with the biologic behavior of the tumor. Nuclei of the cells obtained from 57 aspiration smears of breast cancers were studied. Dimensional parameters (area, perimeter, maximum diameter and roundness factor) and analytic parameters were computed by the Shape Analytical Morphometry software system to evaluate both contour irregularities and asymmetry of nuclear shape. All the tumors were subdivided according to their diameters into two groups: T1 tumors, the maximum diameter of which was < 2 cm (18 cases), and T2 tumors, the maximum diameter of which was > 2 cm and < 5 cm (39 cases). Among T1 tumors, both dimensional and analytic parameters were highly significant (P < .001) in distinguishing tumors with (N+) and tumors without (N-) axillary metastases, while among larger tumors (T2) only the analytic parameters showed degrees of significance, albeit variable. It could be inferred that in smaller tumors, aggressiveness is related to an increase in nuclear dimensions and shape distortions more so than in larger tumors.

Biopsy, Needle↗