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G Gasparini

Publications and source records attributed to G Gasparini.

At least 73 records · Page 4Linked to original sources
PubMed1998

[The importance of the correct restoration of the transverse dimension in midfacial fractures].

The final goal, in reconstructing the facial skeleton of trauma patients, is to obtain good aesthetic and functional outcomes. The surgical technique shown, consists in the reduction and contention of the midfacial fractures. It is based on right placing of the zygomatic arch. In fact, the key to repair midfacial fractures, is the correct placing of the zygomatic arch in relation to the cranial base and the midface. In this way the transversal, vertical and sagittal diameters are regained in their correct space relationships.

Esthetics, Dental↗
PubMed1997

A model for the explanation of the thermally induced increase of the overall fluorescence in tryptophan-X peptides.

In the range of temperature 10-35 degrees C, Trp-X dipeptides show an unusual increase of fluorescence intensity in solution at pH 7. This effect has been recently studied by means of steady-state fluorescence. Although a model involving the deprotonation at the ground state of the zwitterion was proposed, the activation energy for that process could not rule out the involvement of excited state. In order to understand the mechanism of the thermal-induced increase of fluorescence, we present here time-resolved fluorescence experiments on Trp-X and X-Trp dipeptides at different pH and excitation wave-length. The fluorescence lifetimes (tau i) decrease in accord to thermal quenching, with activation energies (Ei) ranging from 4.0 to 6.4 kcal/mol. Under those circumstances where the anomaly was detected the preexponential factors of the longer-lived component increased as well as their fractional fluorescence. This component can be assigned to the anion species. Because of its larger (three- to fourfold) fluorescence quantum yield, compared to that of the corresponding zwitterion, the large increase of the concentration of the anion leads to an increase of the overall emission despite the thermal quenching. Also the decay-associated spectra well account for the red shift of the emission fluorescence spectrum, which accompanies the anomaly. Our model well fits the experimental data using a simple equation which combines Van't Hoff and Arrhenius equations; it also explains the presence of the anomalous thermal quenching exclusively in Trp-X dipeptides excited above 290 nm and at pH around neutrality.

Calorimetry↗
PubMed1997

Prognostic significance of vascular endothelial growth factor protein in node-negative breast carcinoma.

BACKGROUND: The clinical outcome is generally positive for patients with node-negative breast carcinoma (i.e., those who do not have detectable metastases in the lymph nodes) who have been treated with surgery or surgery plus radiation therapy. In about 30% of the patients, however, the disease recurs, and they are at risk of death. Determination of valid new prognostic indicators would improve the ability to identify patients at high risk of recurrence. Breast cancer can entail substantial development of new blood vessels within the tumor tissue, and it is known that the growth and metastasis of solid tumors are dependent on such angiogenesis. The conversion of tumor cells to an angiogenic phenotype may be preceded by a change in the balance of angiogenic growth factors and angiogenesis inhibitors. PURPOSE: This study was conducted to determine if the levels of vascular endothelial growth factor (VEGF) protein, a potent endothelial growth factor and mediator of vascular permeability and angiogenesis, measured in the primary tumors of women with node-negative breast cancer are associated with known prognostic factors and patient survival. METHODS: By use of a selective enzymatic immunoassay, levels of VEGF protein were measured in cytosolic extracts of primary tumor tissue surgically obtained from 260 women with node-negative breast carcinoma who had been treated with surgery with or without radiation therapy but not with adjuvant therapy and who had been followed for a median time of 66 months. The relationships between VEGF concentrations and other prognostic dichotomous variables or clinical outcome were tested by the use of the Kolmogorov-Smirnov test and univariate and multivariate Cox analyses, respectively. The relationship between VEGF and hormone receptors (i.e., those for estrogen and progesterone) was examined by the use of Spearman's correlation analyses. All P values resulted from the use of two-sided statistical tests. RESULTS: Tumors from 247 (95%) of the 260 patients had detectable VEGF, ranging in concentration from 5.0 to 6523 pg/mg protein (median, 126.25 pg/mg protein). No statistically significant associations were found between VEGF and the other prognostic factors (e.g., age, menopausal status, histologic tumor type, tumor size, and hormone receptors) examined. Levels of VEGF were found to be prognostic for both relapse-free and overall survival in univariate and multivariate analyses (likelihood ratio tests; all four P values < .001). In the multivariate analysis, the first-order interaction term of VEGF and estrogen receptor was also prognostic for overall survival (likelihood ratio test; P = .05). CONCLUSIONS: The results show that cytosolic levels of VEGF in tumor tissue samples are indicative of prognosis for patients with node-negative breast carcinoma.

Adult↗
PubMed1997

Massive osteolysis induced by high molecular weight polyethylene wear debris.

We investigated the mechanism by which particulate wear debris of polyethylene may induce bone resorption using an in vivo model. Two uncemented total hip prostheses, in which the socket was directly in contact with acetabular bone, were selected because there was massive bone loss around the implant. A thick synovium-like layer was found at the polyethylene-bone interface during revision operations. Samples were examined by transmitted and polarised light microscopy, and by transmission electron microscopy. This study demonstrates that polyethylene wear products alone can cause massive osteolysis by triggering the formation of foreign body granuloma at the bone-implant interface.

Female↗
PubMed1997

The combined evaluation of p53 accumulation and of Ki-67 (MIB1) labelling index provides independent information on overall survival of ovarian carcinoma patients.

BACKGROUND: The prognostic implications of p53 accumulation, bcl-2 immunoreactivity and tumour proliferative fraction in ovarian carcinomas are still debated. PATIENTS AND METHODS: One hundred twelve ovarian carcinomas were immunostained for p53 protein, for bcl-2 and for the cell cycle-associated Ki-67 antigen. The immunostaining results were correlated with conventional clinico-pathological variables, response to induction chemotherapy, and patient survival. RESULTS: p53 accumulation and bcl-2 immunoreactivity in more than 10% of neoplastic cells were detected in 61 (54.5%) and 42 (37.5%) cases, respectively. A positive correlation between p53 accumulation and high (more than 30% neoplastic cells) MIB1 labelling index (r = 0.235; P = 0.015) was ascertained, whereas no significant association was found between bcl-2 immunoreactivity and p53 accumulation or MIB1 labeling index. Both p53 accumulation and MIB1 immunoreactivity correlated significantly with a reduced overall survival, but the association was lost in multivariate analysis. However, patients with tumours simultaneously showing p53 accumulation and MIB1 labelling index higher than 30% had significantly reduced overall survivals, in both univariate and multivariate analyses. CONCLUSION: The simultaneous evaluation of p53 accumulation and MIB1 labelling index has independent prognostic implications in common epithelial malignancies of the ovary, irrespective of the disease stage.

Cell Division↗
PubMed1997

Co-determination of the angiogenic factors thymidine phosphorylase and vascular endothelial growth factor in node-negative breast cancer: prognostic implications.

Experimental and clinical studies have shown that human breast cancer is an angiogenesis-dependent neoplasm. In fact, several authors have demonstrated that the determination in primary tumors of the degree of vascularization (microvessel counts) as well as of some angiogenic peptides is of prognostic value. However, which are the most important mediators of angiogenesis and their relationship with other relevant biological markers needs further investigation. In the series of 260 women with node-negative breast cancer (NNBC) on which we previously assessed vascular endothelial growth factor (VEGF), we have now also determined thymidine phosphorylase (TP) protein as well as p53 protein and Cathepsin-D cytosolic levels using immunometric methods. The median concentrations of TP, p53 and Cathepsin-D were 105.4U/mg (range 1.2-843.1), 0.22 ng/mg (range 0.0-41.65) and 33.80nmol/mg (range 4.20-216.0), respectively. We found that TP concentrations were associated with Cathepsin-D and p53, but not with VEGF. VEGF (p<0.0001) and p53 (p = 0.03 and p = 0.012, respectively) were found to be statistically significant prognostic variables for both relapse-free survival (RFS) and overall survival in univariate analysis. Conversely, TP and Cathepsin-D levels did not correlate with prognosis. In multivariate analysis for RFS, VEGF levels (p<0.0001), TP levels (p = 0.050) and their first-order interaction terms (p = 0.027) were statistically significant prognostic indicators. Cathepsin-D and p53 protein levels did not retain significance in the model inclusive of all the above variables. The predictive capability of the complete model was satisfactory (Harrell c statistic = 0.72). Moreover, these results suggest a possible potentiation of the capability of predicting the likelihood of recurrence by the co-determination of TP and VEGF. The probability of recurrence was particularly high in the patients with primary tumors characterized by elevated levels of both angiogenic factors. This is the first study showing in vivo that two different angiogenic peptides concur in the progression of human breast cancer. The biology and possible therapeutic implications of this observation are discussed.

Journal Article↗
PubMed1997

In vitro inhibition of endothelial cell growth by the antiangiogenic drug AGM-1470 (TNP-470) and the anti-endoglin antibody TEC-11.

Angiogenesis plays a key role in tumor growth, progression and metastasis. The modulation of angiogenesis represents a potentially useful target for novel forms of anticancer therapy. Two such modulators are AGM-1470 (TNP-470, angioinhibin), which is a synthetic analog of the antibiotic fumagallin, and the monoclonal antibody TEC-11 to endoglin. We investigated the mechanisms of action of these modulators on human microvascular and macrovascular endothelial cells and on the transformed endothelial cell line ECV-304 in vitro. The administration of AGM-1470 or TEC-11 resulted in a significant inhibition of cell proliferation in all cell types used; this effect was reversible upon removal of these compounds from the culture medium. Furthermore, biochemical and morphological analyses showed that neither AGM-1470 or TEC-11 induce apoptosis. Both AGM-1470 and TEC-11 inhibited the production of urokinase-type plasminogen activator (u-PA), an enzyme involved in the early steps of neovascularization. Finally, the incubation of endothelial cells with both AGM-1470 and TEC-11 did not produce an additive effect on growth cell inhibition, apoptosis or u-PA production. Since both AGM 1470 and TEC-11 inhibit crucial events such as endothelial cell growth and protease production, our results provide a basis for their therapeutic use as angiostatic molecules in cancer.

Antibiotics, Antineoplastic↗
PubMed1997

Associated lumbosacral junction injuries (LSJIs) in pelvic fractures.

OBJECTIVE: To study lumbosacral junction injuries (LSJIs) associated with displaced sacral fractures. DESIGN: Prospective. SETTING: University hospital. PATIENTS: Eighty-nine patients with pelvic fractures. INTERVENTIONS: All patients underwent standard x-ray examination consisting of anteroposterior and inlet and outlet views of the injury. In 50 percent of the cases, oblique views were also obtained. Computed tomography (CT) scans were obtained for all vertically unstable lesions and for fifteen of the lateral compression lesions. MAIN OUTCOME MEASURES: Pelvic fractures were classified according to Tile's classification. LSJIs associated with pelvic ring fractures were classified according to Isler. RESULTS: Lumbosacral junction injuries, including one bilateral lesion, were found in thirteen patients. One lesion was associated with a compression fracture, and the other twelve were associated with vertically unstable fractures. In one patient, a facet fracture was associated with a contralateral sacroiliac joint dislocation. A new type of LSJI was identified in three patients: it was characterized by disruption of the annulus fibrosus associated with rising of the hemipelvis and inclination of the L5 body. CONCLUSION: Lumbosacral junction injuries should be suspected in cases of transforaminal sacral fracture, especially when these fractures are displaced. In such cases, we recommend that the lumbosacral junction be evaluated with appropriate CT scans.

Adolescent↗
PubMed1997

Osteoarticular bacterial infections are rare in HIV-infected patients. 14 cases found among 4,023 HIV-infected patients.

Among 4,023 HIV-infected patients admitted to a large Italian university hospital in the period 1985-1996, 14 had concomitant HIV and bacterial osteoarticular infections. Staphylococcus aureus infections were commonest and were diagnosed in 8 patients. Intravenous drug addiction was the only risk factor significantly associated with the development of osteoarticular infection (p = 0.04). In contrast, no statistical correlations were found with age, sex, absolute number of circulating T-CD4+ lymphocytes, neutrophils and stage of HIV infection. In conclusion, osteoarticular infections are uncommon in HIV-infected patients and are more directly related to parenteral drug abuse than to HIV.

Adult↗
PubMed1997

Unique digital skin lesions associated with systemic sclerosis.

A 40-year-old woman with systemic sclerosis presented with multiple, large soft skin lesions with a cystic appearance over the interphalangeal joints of both hands. Aspiration of one of these lesions revealed the presence of a yellowish mucoid material which rapidly reappeared. Surgical dissection and excision of the masses was followed by recurrence a few months later. Pre-operative diagnosis was that of myxoid cysts, but the histological picture was reminiscent of cutaneous focal mucinosis, another form of primary mucinosis. The origin of these unique skin lesions is unclear, but speculation on a possible aetiological relationship between them and systemic sclerosis is presented.

Adult↗
PubMed1997

Non-small-cell lung carcinoma tumor growth without morphological evidence of neo-angiogenesis.

Neoplastic growth is usually dependent on blood supply, and it is commonly accepted that this is provided by the formation of new vessels. However, tumors may be able to grow without neovascularization if they find a suitable vascular bed available. We have investigated the pattern of vascularization in a series of 500 primary stage I non-small-cell lung carcinomas. Immunostaining of endothelial cells has highlighted four distinct patterns of vascularization. Three patterns (which we called basal, papillary, and diffuse) have in common the destruction of normal lung and the production of newly formed vessels and stroma. The fourth pattern, which we called alveolar or putative nonangiogenic, was observed in 16% (80/500) of the cases and is characterized by lack of parenchymal destruction and absence of both tumor associated stroma and new vessels. The only vessels present were the ones in the alveolar septa, and their presence highlighted, through the whole tumor, the lung alveoli filled up by the neoplastic cells. This observation suggests that, if an appropriate vascular bed is available, a tumor can exploit it and grows without inducing neo-angiogenesis. This could have implications for strategies aimed at inhibiting tumor growth by vascular targeting or inhibition of angiogenesis.

Biomarkers, Tumor↗
PubMed1996

Prognostic and predictive value of tumour angiogenesis in ovarian carcinomas.

Experimental studies suggest that angiogenesis plays an important role in the pathogenesis of ascites and progression of ovarian cancer. To evaluate the association of intratumoral microvessel density (IMD) with the conventional clinicopathologic features and to determine the capability of these factors in predicting responsiveness to platinum-based chemotherapy and overall survival (OS) we studied 112 ovarian carcinomas. IMD was determined using the anti-CD31 antibody and immunocytochemistry. In the entire series, we correlated IMD with the other features. In the subgroup of patients with FIGO stage III-IV (60 cases), we correlated the factors studied, determined prior of treatment, with response to therapy and prognosis. The median IMD value, in the "hot spot", in the entire series was of 48 microvessels/field. IMD values were significantly higher in mucinous carcinomas than in the other histologic types. In FIGO stage III-IV patients IMD, age and performance status (PS) were significantly associated with the probability of pathologic response to chemotherapy in univariate analysis. However, only IMD and PS retained significance in multivariate analysis. The overall capability of the 2 variables to predict response was high. In FIGO stage III-IV patients IMD, age, PS, the amount of post-operative residual disease (PORD), histologic type and response to chemotherapy were significant prognostic indicators of OS in univariate analysis. In multivariate analysis only histologic type, PORD and PS retained significance. The overall capability of these 3 variables to predict OS was satisfactory.

Adult↗
PubMed1996

Lack of prognostic significance of the monoclonal antibody Ki-S1, a novel marker of proliferative activity, in node-negative breast carcinoma.

In a series of 205 node-negative breast cancers (NNBC), we determined staining by the novel antibody Ki-S1, a marker of tumor cell proliferation, in order to test its association with other prognostic variables and its prognostic significance. Ki-S1 was determined in routinely formalin-fixed paraffin-embedded tumor samples. Ki-S1 gave a nuclear staining in the majority of the carcinomas (188 of 205), with percentages of reacting nuclei ranging from 2% to 90% (median value of 7%). In 107 tumors frozen sections were available to also assess the Ki-67 antibody. Among these, 94 had a nuclear staining of cancer cells ranging from 5% to 80% (median value of 7%). In 46 tumors we also determined the MIB-1 antibody. The percentage of MIB-1 nuclear staining ranged from 1% to 50% (median value of 20%). There was no significant relationship between Ki-S1 and the other two cell kinetic markers. Ki-S1 labeling was significantly associated only with tumor size (p = 0.03). With a median follow-up of 6 years, Ki-S1 had no significant prognostic value for either relapse-free survival (RFS) or overall survival (OS) (Ki-S1 as continuous logarithmic variable; p = 0.86 and p = 0.23, respectively). For RFS the following variables had a significant prognostic value: Ki-67 (< or = 10% vs > 10%; p = 0.037); progesterone receptor (PgR) expression (- vs+/++; p = 0.041); tumor size (pT1 vs pT2-3; p = 0.042) and grading (GI vs GII-III; p = 0.047). For OS, tumor size (p = 0.0044), age (continuous variable; p = 0.0060), and Ki-67 (p = 0.043) were significantly prognostic. In multivariate analysis (final model), only tumor size retained a significant and independent prognostic value for RFS (p = 0.0042). For OS, both tumor size (p = 0.0029) and age (< or = 55 years vs > 55 years; p = 0.041) retained significance in the multivariate model. In conclusion, Ki-S1 does not seem to have prognostic relevance in this series of NNBC. Possible hypotheses to explain this observation are discussed.

Antibodies, Monoclonal↗