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Biomedical subjects

P G Betta

Publications and source records attributed to P G Betta.

At least 37 records · Page 2Linked to original sources
PubMed1992

Immunophenotypic characterization of the bladder mucosa infiltrating lymphocytes after intravesical BCG treatment for superficial bladder carcinoma.

The lymphocytes infiltrating the bladder mucosa of 28 patients treated with bacillus Calmette-Guérin (BCG) for superficial bladder carcinoma were characterized using an immunohistochemical technique on frozen sections of biopsy specimens obtained during cystoscopy. The inflammatory response induced by BCG consisted mainly of T lymphocytes (CD3+), most of which had the helper/inducer phenotype (CD4+), with a CD4/CD8 ratio greater than 1. A minor subset of lymphocytes were of B phenotype (CD22+). These findings persisted for the whole follow-up period (6-12 months) in spite of a progressive decrease of the inflammatory infiltrate. No difference in the lymphocyte phenotype was observed between nonresponding patients and those who responded to BCG in the short term. It is concluded that, although intravesical BCG therapy does affect the immunocompetent cells of the bladder wall, the BCG-induced antitumor activity is unlikely to depend exclusively on a local immune mechanism.

Administration, Intravesical↗
PubMed1992

Synovial sarcoma: a new approach to the histological classification and a comparison with malignant mesothelioma. Immunohistochemical study with anti-mesothelial cell serum.

Routine paraffin-embedded sections from synovial sarcomas in 70 patients were stained immunohistochemically with monoclonal anti-cytokeratin antibody and serum against mesothelial cells. Positive reactions occurred in the epithelioid cells of biphasic tumors only. On the ground of the reaction with anti-mesothelial serum a hypothetical scheme of cell differentiation in synovial sarcoma was set up.

Antibodies, Monoclonal↗
PubMed1992

Benign mixed salivary-type tumour of the breast.

A case of benign mixed salivary-type tumour of the breast is described. This is a rare neoplasm, only 20 cases having been reported to date, characterized by a mixture of epithelial and mesenchymal components, as in similar tumours occurring in the salivary glands and skin. Because this tumour frequently simulates carcinoma clinically, mammographically and histologically, familiarity of both the surgeon and pathologist with this lesion is essential, to avoid the overdiagnosis of malignancy, unfortunately initially made in nearly 50% of previously reported cases.

Adenoma, Pleomorphic↗
PubMed1992

Mitogenic effects of a mesothelial cell growth factor: evidence for a potential autocrine regulation of normal and malignant mesothelial cell proliferation.

We have investigated the growth-factor-like activity of a approximately 200-kDa, IP 8.3, cytoplasmic glycoprotein, the expression of which appears to be restricted to normal and malignant human mesothelium. This substance stimulated the growth of human mesothelioma cell cultures at greater rates than did foetal calf serum, but it failed to induce proliferation of lung carcinoma cell cultures. In addition, we have tried to trace the biosynthetic pathway of this mitogenic factor in normal human mesothelial cells by means of immuno-electron microscopy with a polyclonal antibody directed against this molecule. Positive immunogold labelling was found in the lumina of the cisternae of the endoplasmic reticulum, to a lesser extent on the outer surface of the plasma membrane, and also in structures corresponding to the coated pits. These ultrastructural findings are consistent with the hypothesis of the glycosylation of the newly synthesized protein in the endoplasmic reticulum and the subsequent uptake of the secreted molecule, which accumulates in the coated pits before internalization. The results suggest that this mitogenic glycoprotein could play a role in an autocrine growth control mechanism influencing mesothelial cell proliferation.

Coated Pits, Cell-Membrane↗
PubMed1991

A new insight into the histogenesis of 'mesodermomas'--malignant mesotheliomas.

A myogenic phenotype was induced in cultures of human mesothelial cells treated for 72 h with atrazine, a triazine derivative. Immunoreactivity for both myosin and myoglobin was detected in a large number of these cells, irrespective of their polygonal or spindle morphology, whereas no expression of desmin was observed. These findings support the embryological identity of mesothelium and mesoderm, the former being, in the post-embryonic stage, potentially capable of differentiation along the same lineages which the latter normally displays during embryogenesis. In the light of this concept it can be assumed that primary malignancies arising from the mesothelium have the competence to express the pluripotent nature of embryonic mesoderm, and hence the term mesodermoma is appropriate for this group of tumours, including mesotheliomas in a classical sense. A postulated mechanism for the phenotypic change of mesothelial cells is also outlined, involving atrazine conversion to 5-aza-chloro-cytidine, a probable DNA hypomethylating and gene activating agent, like its analogue 5-azacytidine.

Atrazine↗
PubMed1991

A one-year carcinogenicity study with 2,6-dichlorobenzonitrile (Dichlobenil) in male Swiss mice: preliminary note.

2,6-Dichlorobenzonitrile (Dichlobenil) is the active principle of a commercial herbicide that was previously shown to be carcinogenic for animals. Dichlobenil was administered to male Swiss albino mice in order to assess the possible oncogenic properties of the active principle alone. The substance at 2 ppm concentration was injected (0.0005 mg/injection) either by subcutaneous or intraperitoneal route to 2 randomized groups of 30 animals each every third day for 13 times. Dichlobenil induced a significant increase of malignant tumors (lymphoma, mesothelioma, hepatocellular carcinoma, and pulmonary alveologenic carcinoma) with respect to the controls (p less than 0.01 in both treated groups). As for tumor histotypes, only lymphoma incidence was significantly increased in the intraperitoneally treated animals (p less than 0.05). Dichlobenil can be suspected of being a possible carcinogen in Swiss mice but the mechanism of its action is not precisely known.

Animals↗
PubMed1990

A morphometrically-based classification rule for the diagnosis of primary mesothelial lesions.

A computer-aided morphometrical study was performed on histological specimens of reactive hyperplastic (n = 10) and malignant (n = 17) mesothelium. For each cell, seven nuclear features were measured and 13 parameters computed. Using stepwise variable selection, discriminant analysis chose the nuclear contour index, the standard deviation of the nuclear area, and the mean of the nuclear perimeter as discriminating features between hyperplastic and malignant mesothelium. The coefficients of these variables were included in a discriminant function which gave perfect discrimination between the two groups of lesions. When the function was assessed on a test set of hyperplastic (n = 10) and malignant (n = 17) mesothelial lesions treated as 'unknown', complete separation between these two diagnostic categories was achieved. This classification rule may help to increase the level of confidence with which a histological diagnosis of mesothelioma can be established.

Cell Nucleus↗
PubMed1989

Verification of the histologic diagnosis of malignant mesothelioma in relation to the binding of an antimesothelial cell antibody.

The diagnostic value of a recently developed polyclonal antibody to mesothelial cells has been tested by means of an immunoperoxidase technique to differentiate mesothelioma from lung carcinoma. All 16 unequivocal mesotheliomas reacted with the antibody, whereas none of the 31 lung carcinomas did, thus confirming the high specificity and the high sensitivity of the antibody. Furthermore, 20 cases of serous membranes tumor, in which major diagnostic disagreement was present when reviewed by the members of the Commission of the European Communities Mesothelioma Panel, were examined. Sixteen of the 20 cases were immunoreactive to the antimesothelial cell antibody, thus establishing their mesothelial origin. Given conventionally fixed and processed tissues, it appears that this antibody may be used as an appropriate diagnostic adjunct to increase the accuracy of the diagnosis of mesothelioma.

Antibodies, Neoplasm↗
PubMed1989

A new method of grading malignancy of prostate carcinoma using quantitative microscopic nuclear features.

A morphometrical assessment of nuclear features and a DNA study were performed on prostate tissue specimens from 33 patients with prostate carcinoma using an image analysing computer. Six nuclear geometric variables were measured and their mean, standard deviation (SD) and standard error (SE) were calculated for each case. The data on nuclear DNA content obtained by static cytometry were processed using an algorithm which provided a DNA grade of malignancy (DNA MG). Using the stepwise multiple regression, we found a significant correlation (p less than 0.01) between the DNA MG, chosen as the dependent variable in the statistical model, and the following nuclear features in decreasing order of importance: area SD, convex perimeter SE, and the mean of maximum diameter. From the correlation coefficients of the variables an equation was built up which provided a geometric nuclear grade of malignancy (GNMG) on a morphometrical basis more closely related to the clinical stage of the tumour (r = 0.75) than the visually assessed histological grade (r = 0.68) based on the Gleason score. This new method of grading malignancy allows an objective and quantitative evaluation to be made of the biological behaviour of the tumour, as measured by the patient's clinical stage.

Cell Nucleus↗
PubMed1989

Putative mesothelial cell growth-promoting activity of a cytoplasmic protein expressed by the mesothelial cell. A preliminary report.

Mesothelioma cells produce a cytoplasmic protein unique to primary tumours of the mesothelium which induces the in vitro proliferation of human mesothelial cells in a dose-dependent fashion. When a polyclonal antibody to this protein was added to cultures of human mesothelioma cells, inhibition of their growth occurred. These results provide evidence for a growth-factor-like role of this mesothelial protein that may act through an autocrine mechanism.

Cell Division↗
PubMed1989

Triazine herbicides and ovarian epithelial neoplasms.

The possible role of a class of herbicides, triazines, in ovarian carcinogenesis has been evaluated in a population-based case-referent study. The trade names reported by the study subjects, and the type of cultivation in which they worked, were used for the assessment of exposure. Women previously exposed to triazines showed a significant relative risk of 2.7 for ovarian neoplasms. Although none of the doses could be quantified for the study subjects, two risk trends in favor of the plausibility of the association were found: the first by duration and the second by probability of exposure. The population representativity of the study and the comparability of information between the cases and referents suggest the lack of any major bias in the results. Triazine-related risk remained consistent when the analysis was restricted to farmers and when the exposure to other herbicides and to other types of cultivation were considered. Unexposed farmers had the same risk as unexposed nonfarmers.

Adult↗
PubMed1989

Correlation of proliferative activity with pathological features in breast carcinoma.

A presently undefined nuclear antigen recognized by the monoclonal antibody Ki-67, and the transferrin receptor (TR), both expressed by proliferating cells, were visualized in cryostat sections of 40 consecutive cases of primary breast cancer using a three-step immunoperoxidase technique. The percentages of Ki-67 and TR positive cells were determined. A strong positive correlation was observed between these two indices of proliferation (p less than 0.01). Moreover, each of them was positively related to the histological tumour grade (p less than 0.01), although the scatter in the number of proliferating cells within each grade was large. No significant relation (p greater than 0.05) was found between the percentages of Ki-67 and TR positive cells and tumor size and between these values and axillary node status. These correlations are similar to those recently reported in the relevant literature and suggest that immunohistochemical assessment of proliferative activity may prove to be an objective indicator of biological behaviour and therefore be of clinical and therapeutical importance.

Adult↗
PubMed1989

The influence of perimenopausal age on estrogen receptor status and estradiol and DNA content in human breast cancer.

In 25 cases of breast cancer occurring in perimenopausal age, estrogen receptor (ER) content was determined by the dextran-coated charcoal (DCC) assay and both endogenous-bound estradiol and nuclear DNA concentrations were measured by computerized quantitative analysis on formalin-fixed paraffin-embedded tissue samples. No statistically significant relationship (p greater than 0.05) was found within these parameters. The high incidence (64%) of ER-negative cases in this menopausal age was mainly due (62.5%) to interference of high levels of endogenous estradiol occupying the receptor sites in-vivo. The prevalence of hormone-insensitive and aneuploid cell clones accounted for the remaining true ER-negative tumours (37.5%).

Age Factors↗
PubMed1988

Uncommon histological variants of clear cell carcinoma of the ovary. Report of two cases with immunohistochemical and ploidy studies.

Two cases of clear cell carcinoma of the ovary with uncommon histological features are here presented. The former showed considerable formation of giant, hCG-negative tumour cells. In the latter the clear cell pattern was admixed with smaller elements that resembled steroid-hormone secreting cells. However, these cells revealed negative immunostaining for testosterone and a higher degree of DNA content abnormalities than the clear cell component.

Adenocarcinoma↗
PubMed1988

Secretory (juvenile) carcinoma of the breast in an adult woman.

A case of secretory (juvenile) carcinoma of the breast is reported in a 31-year-old woman. Secretory carcinoma in adults is rare, only twenty-seven cases previously reported. It is known to have a more favourable prognosis than the conventional ductal carcinoma. The most adequate treatment appears to be a simple mastectomy with low axillary dissection.

Adult↗
PubMed1988

Hemangioma of the ovary.

A case of ovarian hemangioma is reported and illustrated with the authors' comments. Few similar cases have been found in a literature review of vascular tumors of the female organs.

Female↗
PubMed1987

Reed-Sternberg cells and their cell microenvironment in Hodgkin's disease with reference to macrophage-histiocytes and interdigitating reticulum cells.

Fifty-eight paraffin-embedded lymph node biopsies from patients with Hodgkin's disease (36 nodular sclerosis, 14 mixed cellularity, five lymphocyte depletion, and three lymphocyte predominance) were immunostained with a panel of monoclonal (anti-Leu-M1, antileukocyte common antigen) and polyclonal (to lysozyme, alpha 1-antitrypsin, alpha 1-antichymotrypsin, and S-100 protein) antibodies by using the avidin-biotin immunoperoxidase technique. Both the immunostaining features of the Reed-Sternberg (R-S) cells and their variants, and the numbers of immunostained accompanying cells morphologically corresponding to macrophage-histiocytes (M-H) and to interdigitating reticulum cells (IRC) were analyzed. Variable numbers of R-S cells and their variants were positive for Leu-M1 in 83% of the cases, for alpha 1-antitrypsin in 40%, for alpha 1-antichymotrypsin in 30%, and for leukocyte common antigen in 3.4%; they were constantly negative for lysozyme and S-100 protein. Whereas the average numbers of accompanying cells immunostained for Leu-M1 were very low, the numbers of S-100-positive IRC were relatively high in all the Hodgkin's subtypes. The average numbers of M-H were lower (P less than 0.1 for lysozyme; P less than 0.001 for alpha 1-antichymotrypsin) in the nodular sclerosis than in the other pooled subtypes. In the nodular sclerosis subtype, however, R-S cells and their variants that stained positive for Leu-M1 appeared to express more frequently the lineage markers of M-H (alpha 1-antitrypsin and/or alpha 1-antichymotrypsin). These data appear to suggest that there is not an apparent qualitative correspondence between the immunostaining features of the cellular microenvironment composed of M-H and IRC and the features of the R-S cells.

Antigens, Differentiation, T-Lymphocyte↗