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Biomedical subjects

A Giuliani

Publications and source records attributed to A Giuliani.

At least 181 records · Page 10Linked to original sources
PubMed1988

Statistical exploration of four major genotoxicity data bases: an overview.

This report puts into perspective a series of exploratory statistical analyses carried out on the major genotoxicity data bases. While large compilations of data, even though computerized, suffer from their own size and are quite intractable to scientific reflection and judgement, the multivariate data analysis methods used by us are specifically designed for reorganising the information in a rational way and highlighting the underlying regularities of the data. The analyses reported here refer to the following data bases: the International Program for the Evaluation of Short-Term Tests for Carcinogens, the International Program on Chemical Safety Collaborative Study on In Vitro Assays, the Gene-Tox data base, and a subset of the U.S. National Toxicology Program data. Although the various data bases consisted of different sets of chemicals and had different underlying rationales, a number of invariant associations among short-term test performances were highlighted. The overall evidence indicated that the traditional classification of assays (according to the criteria of genetic end-point and phylogenetic position of the assays) was in contrast with the actual, operational similarities among assay performances, in that the experimental responses of the tests to the large variety of chemicals under consideration pointed to an alternative classification scheme. This consisted of three major classes: 1) a class comprising the in vivo assays; 2) a class grouping together many of the most widely used in vitro assays (Salmonella, chromosomal aberrations, and sister chromatid exchanges in Chinese hamster ovary cells, the various mutation tests in mammalian cell systems, etc.); 3) a second in vitro assay class (with Syrian hamster embryo cell transformation, Saccharomyces cerevisiae XV185-14C, B. subtilis rec-, Escherichia coli pol A). Such classes had clearly differentiated features with respect to carcinogenicity prediction. The implications of these findings for the current debate on mutagenicity testing are discussed.

Carcinogens↗
PubMed1988

Influence of cetylpyridinium chloride on the ultrastructural appearance of sulphated glycosaminoglycans in human colonic mucosa.

The effect of adding cetylpyridinium chloride to the fixative on the preservation of sulphated glycosaminoglycans (SGs) was studied in human normal colonic mucosa. SGs were visualized at the ultrastructural level through the application of Spicer's High Iron Diamine (HID) technique followed by a post-fixation with potassium ferrocyanide-reduced osmium tetroxide. SGs were mainly localized in basement membranes of epithelium and capillary wall and along collagen fibers. The morphology of the reactive sites depended on the presence of cetylpyridinium chloride, SGs being granular in absence of the salt and more or less elongated when cetylpyridinium chloride was added to the fixative. We suggest that the use of cetylpyridinium chloride during fixation may help to preserve SG molecule at the ultrastructural level.

Cetylpyridinium↗
PubMed1988

Computer-assisted analysis of interlaboratory Ames test variability.

The interlaboratory Ames test variability of the Salmonella/microsome assay was studied by comparing 12 sets of results generated in the frame of the International Program for the Evaluation of Short-Term Tests for Carcinogens (IPESTTC). The strategy for the simultaneous analysis of test performance similarities over the whole range of chemicals involved the use of multivariate data analysis methods. The various sets of Ames test data were contrasted both against each other and against a selection of other IPESTTC tests. These tests were chosen as representing a wide range of different patterns of response to the chemicals. This approach allowed us both to estimate the absolute extent of the interlaboratory variability of the Ames test, and to contrast its range of variability with the overall spread of test responses. Ten of the 12 laboratories showed a high degree of experimental reproducibility; two laboratories generated clearly differentiated results, probably related to differences in the protocol of metabolic activation. The analysis also indicated that assays such as Escherichia coli WP2 and chromosomal aberrations in Chinese hamster ovary cells generated sets of results within the variability range of Salmonella; in this sense they were not complementary to Salmonella.

Analysis of Variance↗
PubMed1988

Increase of natural killer activity of mouse lymphocytes following in vitro and in vivo treatment with lithium.

The in vivo and in vitro influence of lithium lactate on mouse natural killer activity was investigated. In vitro exposure of effector-target mixture to graded concentrations of lithium did not substantially modify the natural killer activity of mouse splenocytes, untreated or pretreated with cyclophosphamide. However in vitro treatment of effector splenocytes increased the frequency of NK-percursor cells. The in vivo treatment with lithium lactate greatly increased the natural killer activity in intact mice, whereas it did not improve this cytotoxic function in host immunodepressed by cyclophosphamide. These data suggest that lithium salts produce a modulation of natural killer activity of mouse spleen cells, probably through a mechanism involving the increase of the number of NK-precursors in hosts not subjected to cytotoxic chemotherapy.

Animals↗
PubMed1988

Mediastinal angiofollicular lymph node hyperplasia, hyaline-vascular type with mucocutaneous manifestations.

A never previously reported association between mediastinal angiofollicular lymph node hyperplasia (ALNH) of the hyaline vascular type and mucocutaneous manifestations in a twenty-one-year-old man is described. Mucocutaneous lesions, unresponsive to medical therapy, promptly disappeared after resection of the mediastinal mass, indicating, as suggested for the plasmacell type, a close relationship between the systemic manifestations and ALNH.

Adult↗
PubMed1988

Dehiscence of intestinal anastomoses and anaesthesia.

This study, carried out in 62 patients undergoing surgery under general anaesthesia, has evaluated the nestigmine effects on tone and motility of the muscular rectal wall, by recording compliance and manometric values. An increase of intrarectal pressure values in patients antagonized with neostigmine has been evidenced. This finding is related to contracture and increased motility of muscular rectal wall, induced by anticholinesterase agent. In patients eligible for intestinal anastomoses, rapidly eliminated myoneural blocker such as atracurium besylate or vecuronium, should be preferred. These agents allow a spontaneous reversal of the myoneural block, without pharmacologic antagonism.

Adult↗
PubMed1988

Delayed bilateral ureteral fistula following abdominoperineal resection: a case report.

A case of delayed bilateral ischemic necrosis of the pelvic ureter in a 66-year-old woman submitted to abdominal perineal resection and hysterectomy for advanced rectal cancer, is reported. Five days after the operation urine was observed in the perineal cavity. External urine diversion was carried out by catheterizing the ureteral stumps through the perineal cavity. The reconstructive procedure was performed at a later date by bilateral ureteroileocystoplasty with a defunctionalized loop. The vascular anatomy of the ureter is discussed to highlight the essential technical details useful for prevention of ischemic injury.

Abdomen↗
PubMed1987

Protein kinase C mediates human neutrophil cytotoxicity.

Human neutrophils stimulated with phorbol myristate acetate were able to damage human erythroleukemic K562 cells, in the absence of specific antibody, as assessed by a two hour 51Cr release assay. Neutrophils treated with formyl-peptide fMet-Leu-Phe did not display tumoricidal response, but the addition of diacylglycerol kinase inhibitor R59022 together with formyl-peptide induced the cytotoxic capacity against tumor target cells. Phorbol ester is a potent activator of certain functions of neutrophils because of its ability to directly and irreversibly stimulate protein kinase C; formyl-peptide, on the contrary, activates protein kinase C by inducing a rapid and transient production of diacylglycerol, that is quickly metabolized. The addition of an inhibitor of diacylglycerol kinase, R59022, however potentiated the action of formyl-peptide. These results indicate that protein kinase C is involved in the tumoricidal activity of neutrophils against K562 cells, and that maximal activation of the enzyme is required to achieve the cytotoxic response.

Cytotoxicity, Immunologic↗
PubMed1987

The conceptual framework of monitoring mutagens/carcinogens: a critical appraisal.

The main theme of this paper is an analysis of the present knowledge and conceptual framework in the field of monitoring for carcinogenic and mutagenic agents. The conclusions of the International Symposium on "Monitoring human exposure to carcinogenic and mutagenic agents" (Helsinki, 1983) were taken as a starting point for a series of considerations; methods suitable for the quantitative treatment of the information were applied to evidence the profile of current research in this area. The analysis indicated that the major underlying paradigms were related to technical considerations, such as chemical specificity, precision, reproducibility or ease of execution, as well as to the concept of mechanism of action of genotoxic agents. On the other hand, the lack of reliable information about the operational relevance of the systems for assessing health effects was dramatically evidenced. As a conclusion, the dangers of relying on a scientific background derived only from the basic research, without a critical re-examination in terms of real, operational performances of the systems, are emphasized.

Carcinogens↗
PubMed1987

Isolation and purification of a major allergen from Parietaria officinalis pollen.

A major allergen of Parietaria officinalis, a species responsible for a large number of respiratory allergies in Mediterranean areas, has been identified and characterized. This allergen (Pol) was found in the fraction which precipitates between 70 and 100% ammonium sulphate saturation. Pol showed a molecular weight of 15,000 daltons as determined by SDS-PAGE and HPLC. The pI of Pol was in the pH region 4-6, IEF showing four major bands. Two major bands were shown by CIE, CRIE and immunoblotting; major contaminants or aggregates were also revealed by the latter technique and by HPLC. Pol showed an allergic specific activity 2 times higher than the crude extract; moreover it was shown to be a major allergen since it inhibited 29 out of 30 sera from allergic patients sensitive to P. officinalis.

Allergens↗
PubMed1987

Combined effects of immunity and antitumor drugs against cancer. II. In vitro studies with cis-diamminedichloroplatinum in a human leukemia system.

Human K562 leukemic cells were exposed in vitro to cis-diamminedichloroplatinum (DDP) followed by addition of intact or irradiated mononuclear cells (MNC) obtained from peripheral blood of normal donors. tumor inhibition provoked by DDP was significantly enhanced by normal MNC, but not by irradiated cells at the effector: leukemic cell ratio of 2:1. In contrast MNC alone did not show appreciable effects on K562 cells. The NK activity of MNC was also inhibited by exposure to gamma rays. The combined effects of DDP + MNC do not appear to be due to increased susceptibility of DDP-pretreated K562 cells to NK-mediated cytolysis. Actually leukemic cells treated with 10 micrograms/ml of DDP and cultured for 48 h at 37 degrees C, showed decline of susceptibility to the cytotoxic effects of MNC. These studies suggest that natural immunity could be of potential value in the clinical use of DDP.

Cell Division↗
PubMed1987

Intrarectal ultrasonography in the preoperative staging of rectal cancer.

Intrarectal ultrasonography is a new imaging method used in the preoperative staging of rectal cancer. Twenty five patients with proven rectal cancer were submitted to preoperative intrarectal ultrasonography; 24 were resected. Real time scanner with a linear probe of 5 MHz was employed. Five sonographic structures corresponding to the five histological layers were evidenced. Ultrasound T staging was compared to pathology, using UICC classification. In all but two cases pathology corresponded to ultrasound T staging (accuracy 92%). Perirectal nodal involvement was also investigated. It is concluded that intrarectal ultrasonography will play a definite role in the preoperative staging as well as in programming treatment of rectal carcinoma.

Adult↗
PubMed1987

Combined effects of immunity and antitumor drugs against cancer. I. In vivo studies with cis-diamminedichloroplatinum and cyclophosphamide in mouse models.

Cis-diamminedichloroplatinum (DDP) or cyclophosphamide (Cy) were given to mice bearing L1210 or LSTRA leukemia in H-2 compatible tumor-host combinations. Little anti-tumor activity was afforded by DDP against both leukemias inoculated in entirely histocompatible recipients. However, when the drug was given to mice incompatible for minor histocompatibility loci (MMHL) with the tumor, the efficacy of the treatment was markedly augmented and a substantial number of long-term survivors was found among BALB/c mice inoculated with L1210 cells. On the other hand, no difference in survival times was found between histocompatible or allogeneic mice inoculated with both leukemias, not subjected to chemotherapy. The LSTRA model was much less susceptible to this type of DDP-mediated antineoplastic immuno-chemotherapy synergism. Moreover no synergistic effects with allograft reaction were detected with Cy in both L1210 and LSTRA models, although Cy was markedly more active than DDP against leukemic cells in histocompatible recipients.

Animals↗
PubMed1987

Hydatid hepatothoracic fistulas. A report of 30 cases.

A retrospective study was carried out on 30 patients with hepatothoracic transdiaphragmatic fistulas, classified as hepatopleural (5 cases), hepatopulmonary (11 cases), biliopleural (1 case) and biliobronchial (13 cases). Investigations included chest X-rays, bronchography, plain abdominal films, cholecystocholangiography, liver scanning, ultrasonography and CT scanning. Twenty-nine patients were submitted to 32 operations: two were performed in 1 case and three in another. Thoracotomy was performed in 20 cases, laparotomy in 7 and thoracophrenolaparotomy in 5. Surgical procedures for the treatment of endothoracic lesions included pleurectomy, middle lobectomy, lower lobectomy and wedge resections. Liver cysts were treated by cystectomy and pericystectomy. The postoperative course was uneventful in 21 patients. Complications developed in 3 patients. Operative mortality was 10.3%.

Adolescent↗
PubMed1987

Polyps of the colon in juvenile and young patients: histological type and C.E.A. content in relation to follow-up.

31 colonic polyps in 21 patients between 2 and 30 years of age removed by endoscopy were studied. The site, size, cytohistological characteristic and tissue CEA content of these polyps were evaluated. 58% of the polyps were located in the rectum and sigmoid, the remaining 42% were in the descending colon. At histological examination 13 polyps proved to be neoplastic, 3 of which had severe dysplasia. In 3 cases of juvenile hyperplastic hamartomatous polyps and in 5 cases of inflammatory polyps the tissue C.E.A. was low; in 13 neoplastic polyps it was in direct correlation with the degree of dysplasia. Moreover in 10 patients with neoplastic polyps, 5 presented further adenomas at follow-up, and in 3 of them the C.E.A. tissue content of the first polyps obtained was medium to high. The occurrence in young patients of polyps of the colon with C.E.A. content medium to high must be followed by endoscopic examination at close intervals.

Adolescent↗