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S Petroni

Publications and source records attributed to S Petroni.

At least 19 recordsLinked to original sources

[Expression of steroid receptors and DNA synthesis in male breast cancer].

Using a double-labeling immunocytochemical-autoradiographic assay we studied 18 male breast carcinomas to evaluate the cell kinetic and receptor status in neoplastic cells during S-Phase and to detect possible differences with respect to 21 female breast cancers, from a previously, published study. In male breast cancer, the tumor receptor content and ER/PgR expression in neoplastic cells during S-Phase was higher (p = 0.01) than that in corresponding female tumor while tumoral cell proliferation was lower, but not significantly. In the previous reported study on female breast cancer we demonstrated that proliferative activity was higher in receptor negative cell population both for ER and PgR. Conversely, in male tumor, that difference was only present in relation to the expression of PgR: in fact, the proliferative activity was higher in PgR negative than in PgR positive cells (Anova Test: p = 0.04) while no difference was evidenced between ER negative versus ER positive cells. Moreover, the arrest of DNA synthesis, expressed as percentage of cells without 3H-Tdr labeling, was not related to either the ER or PgR expression, while in female breast cancer it was higher in PgR positive than ER positive cell population. Our data confirmed differences between males and females regarding the receptor status and cell cycle S-Phase in breast cancer. The poorer prognosis of the male breast carcinoma might be related to ineffective therapies which do not consider these differences in the biological profile of the male tumor. The Authors indicate that prognostic and predictive tissutal markers, detected by immunocytochemical methods and useful for therapeutic programming in the female breast cancer have a different significance in the male breast cancer and stress the need for different therapeutic strategies specific for male breast cancer.

Adult↗

nm23 expression in malignant ascitic effusions of serous ovarian adenocarcinoma.

The aim of this study was to evaluate nm23 expression as detected in malignant cells of neoplastic ascites and to verify its relationship with the presence of tissue nm23 and p53 in primitive neoplasia. Using an immunocytochemical assay with a specific anti-nm23 polyclonal antibody, nm23 expression was evaluated in ascitic effusions of 45 patients with ovarian serous adenocarcinoma and ascites in normal and/or hyperplastic mesothelial cells from 37 women with various neoplasms (12 ovarian neoplasms) free of malignant cells as controls. nm23 and p53 tissue expression was also detected in 21 corresponding tumor samples, including 11 bilateral lesions. nm23 was expressed in 57% of malignant effusions compared to 43% in controls: the two groups were not correlated. nm23 in effusions agreed with tissue expression (p=0.02) but a direct correlation was not demonstrated. The incidence of nm23 was more frequent in stage III than in stage IV disease (p=0.08) and was associated with mutated p53 expression (p=0.01). Using the Wilcoxon test for unpaired data, a higher incidence (p=0.05) of p53-positive tumors in bilateral cancers was found while a higher expression of nm23 in effusions of patients with monolateral lesions was observed (p=0.08). The presence of p53 was correlated with that of nm23 in both cytologic (p=0.005) and histological samples (p=0.01). Our findings, together with the diversity in biological behaviour present in various tumors, suggest that nm23 is a family of genes with differing biological functions which act as tumor-specific inhibiting factors within a complex process also involving other genes. Due to the analogies and correlations between nm23 and p53, the role of nm23 as a potential predictive factor of response to chemotherapy and in DNA repair is emphasized.

Aged↗

Thymidilate synthase and p53 primary tumour expression as predictive factors for advanced colorectal cancer patients.

The purpose of this work was to analyse the ability of p53 and thymidilate synthase (TS) primary tumour expression to retrospectively predict clinical response to chemotherapy and long-term prognosis in patients with advanced colorectal cancers homogeneously treated by methotrexate (MTX)-modulated-5-fluorouracil (5-FU-FA). A total of 108 advanced colorectal cancer patients entered the present retrospective study. Immunohistochemical p53 (pAb 1801 mAb) and TS (TS106 mAb) expression on formalin-fixed paraffin-embedded primary tumour specimens was related to probability of clinical response to chemotherapy, time to progression and overall survival. p53 was expressed in 53/108 (49%) tumours, while 54/108 (50%) showed TS immunostaining. No relationship was demonstrated between p53 positivity and clinical response to chemotherapy (objective response (OR): 20% vs 23%, in p53+ and p53- cases respectively) or overall survival. Percent of OR was significantly higher in TS-negative with respect to TS-positive tumours (30% vs 15% respectively; P < 0.04); simultaneous analysis of TS and p53 indicated 7% OR for p53-positive/TS-positive tumours vs 46% for p53-positive/TS-negative tumours (P < 0.03). Logistic regression analysis confirmed a significant association between TS tumour status and clinical response to chemotherapy (hazard ratio (HR): 2.91; 95% confidence interval (CI) 8.34-1.01; two-sided P < 0.05). A multivariate analysis of overall survival showed that only a small number of metastatic sites was statistically relevant (HR 1.89; 95% CI 2.85-1.26; two-sided P < 0.03). Our study suggests that immunohistochemical expression of p53 and TS could assist the clinician in predicting response of colorectal cancer patients to modulated MTX-5-FU therapy.

Adult↗

Ultrastructural alterations of choroid plexuses of lateral ventricles of rats (Rattus norvegicus) submitted to experimental chronic alcoholism.

Adult male rats (Wistar lineage) were alcoholized with sugar cane liquor diluted at 30(0) GL during 300 days and sacrificed every 60 days in 5 stages. Samples of choroid plexuses of lateral ventricles were collected and examined at transmission electronic microscope to detect possible ultrastructural alterations and to raise possible pathological correlations. Gradual changes were observed in these animals during all the experiment: dilatation and enlargement of cisternae of Golgi complex, dilatation of RER, presence of digestive vacuoles and a large amount of pinocytic vesicles as well as vesicles with electronlucent content throughout cytoplasm, as well as an enlargement of intercellular space between basolateral interdigitation of the cells and of the connective tissue. The changes observed in the epithelium and connective tissue of choroid plexuses specially in 240 and 300 days of treatment are presumably due to a disturbance in hydroelectrolitic homeostasis, contributing to several morpho-functional disturbs of central nervous system. No changes were observed in the control group animals.

Alcoholism↗

Scanning electron microscopy study of the choroid plexus in the monkey (Cebus apella apella).

The cells of the choroid plexus of the lateral ventricles of the monkey Cebus apella apella were examined through scanning electron microscopy at contributing to the description of such structures in primates. The animals were anesthetized previously with 3% hypnol intraperitoneally and after perfusion with 2.5% glutaraldehyde, samples of the choroid plexus were collected after exhibition of the central portion and inferior horn of the lateral ventricles. The ventricular surface of those cells presents globose form as well as fine interlaced protrusions named microvilli. Among those, it is observed the presence of some cilia. Resting on the choroid epithelial cells there is a variable number of free cells, with fine prolongations which extend from them. They are probably macrophages and have been compared to Kolmer cells or epiplexus cells, located on choroid epithelium. The choroid plexus of the encephalic lateral ventricles of the monkey Cebus apella apella at scanning electron microscopy is similar to that of other primates, as well as to that of other species of mammals mainly cats and rats, and also humans.

Animals↗

nm23 expression in human breast cancer: correlation with cell proliferation (S-phase) as observed with a double-labeling immunocytochemical-autoradiographic technique.

In 51 unselected breast cancer samples, a double-labeling immunocytochemical technique was utilized to observe the phenotypic expression of the nm23 gene during S-phase. The feasibility of the method was confirmed by comparison with routine evaluations for both thymidine-labeling index and nm23 (p<0.001). No correlation was found between the two parameters in the overall series or when subgroups regarding menopausal status, nodal involvement, tumor size, hormone receptor content were considered. Tumors with a higher nuclear grade showed a significant correlation only with TLI (p=0. 02). A trend for an inverse relationship between the two parameters was noted but was not statistically significant. A significant association between TLI and nm23 expression was found by Chi-square test using median values as cut-off. Our data based on morphological and in situ observations do not confirm a correlation between nm23 and cell proliferation, even if this correlation cannot be completely excluded. Multicentric trials of high power with these same techniques are still necessary to definitely establish the prognostic role of nm23 in breast cancer.

Adult↗

Timing of breast cancer surgery within the menstrual cycle: tumor proliferative activity, receptor status and short-term clinical outcome.

We verified the variations of primary tumour steroid receptor status and proliferative activity at different times and phases (follicular vs luteal) of the menstrual cycle and their relationship with short clinical outcome in a cohort of 248 N- breast cancer patients. Steroid receptor content (ER and PgR) was evaluated by DCC assay and proliferative activity by 3H-Thymidine autoradiographic assay (TLI). Median age was 44 years, 60% of tumors were T1, and cytohistological grade was G1-2 in 54% of cases. At surgery, 57% were in the luteal phase while 43% were in the follicular phase. No significant variations were found in mean TLI or ER and PgR characteristics of the primary tumors surgically treated in different periods of the menstrual cycle; however, the ER level resulted significantly higher in 4th with respect to the 3rd week of menstrual cycle, while PgR level was higher in PgR+ cases treated during the 3rd week. The number of relapses and disease-free survival curves after 36 months median follow-up did not differ significantly for patients treated in different periods of the menstrual cycle (12% and 9% of disease relapses in luteal and follicular phases; p=n.s.). We can conclude, therefore, that TLI, ER and PgR expressions could vary significantly during menstrual cycle only in certain specific tumor subgroups.

Adult↗

[Dna synthesis and expression of steroid receptors in cells of human breast carcinoma].

In order to observe receptor expression (ER and PgR) in human breast cancer cells during the S-phase of the cellular cycle, we evaluated 21 tumoral samples using a double labeling immunocytochemical-autoradiographic assay. In 16 of these we have verified that expression of ER and PgR is not influenced by incubation with 3H-Thymidine for 60 minutes. The results also demonstrated that receptor expression during the S-phase is more common in postmenopausal tumors and is principally dependent on percentages of ER+ (p < 0.01) and PgR+ (p < 0.01) cells; moreover, proliferative activity occurs almost exclusively in ER- (p = 0.003) and Pgr- (p = 0.001) cellular sub populations and the presence of PgR, but not of ER, is related to arrest of DNA synthesis (p = 0.02).

Adult↗

Quantitative molecular monitoring of human immunodeficiency virus type 1 activity during therapy with specific antiretroviral compounds.

Methods for the absolute quantitation of nucleic acids present in small amounts in biological samples (competitive PCR and competitive reverse transcription PCR) were applied to the direct monitoring of specific anti-human immunodeficiency virus type 1 (HIV-1) therapy. With these techniques, different parameters of HIV-1 activity (including genomic RNA copy numbers in plasma, proviral and late transcript copy numbers in peripheral blood lymphocytes, and mean transcriptional activity per each HIV-1 provirus) were monitored during therapy with azidothymidine or ddI. In most of these treated patients, a direct response to the antiretroviral compounds employed was detected during the first few weeks of treatment, as documented by a fast decrease of all molecular indexes of HIV-1 activity. However, residual viral replication (albeit at minimal levels) was documented during therapy in all subjects monitored in this study. In a minority of the patients under study (3 of 12), the drug-dependent viral inhibition was maintained throughout the observation time (213 to 791 days), but in 9 patients a rebound in viremia level was detected during therapy with competitive reverse transcription PCR. Sequencing analysis of a portion of the HIV-1 gene pol from cell-free virions showed that circulating viral variants bearing at least two mutations compatible with azidothymidine or ddI resistance were detectable in the patients who exhibited a rebound in cell-free HIV-1 genomic RNA copy numbers in plasma but not in one patient who maintained (for 455 days) lowered levels of viral load during ddI treatment.

Amino Acid Sequence↗

Imipenem and meropenem induced resistance to beta-lactam antibiotics in Pseudomonas aeruginosa.

The ability of imipenem and meropenem in subinhibitory concentrations to influence the results of disk diffusion susceptibility tests was assessed. Selection of stably derepressed mutants resistant to beta-lactam antibiotics other than carbapenems was also investigated. Beta-lactams were shown to be subject to carbapenem-mediated antagonism in the disk diffusion test. On the other hand in vitro selection of stably derepressed mutants resistant to other beta-lactams could not be demonstrated.

Anti-Bacterial Agents↗

Epidemiological surveillance of staphylococcal resistance.

The aim of our investigation was to characterize better the possible changes in staphylococcal susceptibility to some antimicrobial agents. We considered the staphylococcal strains isolated between June 1986 and June 1989 and held responsible for proved bacterial infections. In this relatively short time we observed a moderate increase in methicillin resistance. Compared with methicillin-sensitive strains, methicillin-resistant isolates showed minor susceptibility to most antimicrobial agents; nevertheless, vancomycin, teicoplanin, cefamandole, imipenem, fluoroquinolones and netilmicin, according to our results, appear at present the most reliable antistaphylococcal antibiotics.

Drug Resistance, Bacterial↗

Correlation between ERICA and DCC assay in hormone receptor assessment of human breast cancer.

To study the basic relationships between estrogen receptor immunocytochemical assay (ERICA) and dextran-coated charcoal (DCC) techniques, 116 women affected by breast cancer were admitted to the study from June 1985. In 56% of cases the tumor sample came from patients with operable disease and in 44% from patients with advanced inoperable disease. We found an overall agreement of 80% between the two methods characterized by a high sensitivity (95%) and a low specificity of ERICA versus DCC. ER/ICA negative results were found in 20 out of 78 ER/DCC positive cases; on the contrary, discordant results were found in only 3 out of 38 cases described by DCC as ER negative. 29 patients with advanced disease and ER/DCC positive tumors were considered for clinical analysis and reliability of each hormone receptor assay. A clinical response was reached in 69% of ER/DCC positive patients and on 64% of ER/ICA positive ones (16/25). However, it must be noted that 4/29 cases described as negative by ERICA were clinically responsive to hormone therapy.

Breast Neoplasms↗

[Receptor status (ER and PgR) determined with histochemical and biochemical methods in breast carcinoma].

Recently, a method similar to ER.ICA has been proposed for the progesterone receptor (PgR) using two monoclonal antibodies, JZB39 and KD68, specific for human PgR and characterized by a molecular weight of 95 and 120 Kd, respectively. A series of 73 breast cancer patients was studied with regards to ER and PgR using both immunocytochemical (ICA) and biochemical (DCC) assays. Results showed no substantial differences between the two methods when considering common clinical-pathological parameters. Overall agreement between ICA and DCC methods was found: 79% for PgR and 78% for ER. A slight quantitative correlation was also observed between the "score values" of the ICA method and the Fmol content of ER and PgR using the Brave-Pearson test (r = 0.49 for PgR; r = 0.43 for ER). Specificity of PgR.ICA method was 77% for PgR and 72% for ER; sensitivity was 82% and 83%, respectively. The ICA method is a reliable technique to assess PgR presence as well as ER. Further studies are necessary to evaluate the prognostic role of nuclear PgR.

Adult↗