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M De Santis

Publications and source records attributed to M De Santis.

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

[Plasma-cell granuloma of the mediastinum].

Plasma-cell granuloma of the mediastinum is an unusual non-neoplastic lesion; a case of rare mediastinal localization is reported. Only the histopathological examination leads to a correct diagnosis. Since the possibility of local recurrence has been described, total excision is requested. Video-assisted thoracic surgery technique may be difficult to use in the management of these mediastinal tumors due to adhesions between the mass and the surrounding tissues. Complete open resection is the treatment of choice.

Granuloma, Plasma Cell↗
PubMed1997

Cripto enhances the tyrosine phosphorylation of Shc and activates mitogen-activated protein kinase (MAPK) in mammary epithelial cells.

Cripto-1 (CR-1), a recently discovered protein of the epidermal growth factor (EGF) family, was found to interact with a high affinity, saturable binding site(s) on HC-11 mouse mammary epithelial cells and on several different human breast cancer cell lines. This receptor exhibits specificity for CR-1, since other EGF-related peptides including EGF, transforming growth factor alpha, heparin-binding EGF-like growth factor, amphiregulin, epiregulin, betacellulin, or heregulin beta1 that bind to either the EGF receptor or to other type 1 receptor tyrosine kinases such as erb B-3 or erb B-4 fail to compete for binding. Conversely, CR-1 was found not to directly bind to or to activate the tyrosine kinases associated with the EGFR, erb B-2, erb B-3, or erb B-4 either alone or in various pairwise combinations which have been ectopically expressed in Ba/F3 mouse pro-B lymphocyte cells. However, exogenous CR-1 could induce an increase in the tyrosine phosphorylation of 185- and 120-kDa proteins and a rapid (within 3-5 min) increase in the tyrosine phosphorylation of the SH2-containing adaptor proteins p66, p52, and p46 Shc in mouse mammary HC-11 epithelial cells and in human MDA-MB-453 and SKBr-3 breast cancer cells. CR-1 was also found to promote an increase in the association of the adaptor Grb2-guanine nucleotide exchange factor-mouse son of sevenless (mSOS) signaling complex with tyrosine-phosphorylated Shc in HC-11 cells. Finally, CR-1 was able to increase p42(erk-2) mitogen-activated protein kinase (MAPK) activity in HC-11 cells within 5-10 min of treatment. These data demonstrate that CR-1 can function through a receptor which activates intracellular components in the ras/raf/MEK/MAPK pathway.

Animals↗
PubMed1997

Effects of lipiodol retention on MRI signal intensity from hepatocellular carcinoma and surrounding liver treated by chemoembolization.

Opinion is divided regarding the influence of iodized oil on MRI signal intensity of hepatic tumours treated with transcatheter arterial chemoembolization (TACE), in which lipiodol deposits. The aim of our study was to ascertain whether or not lipiodol directly influences the MRI signal intensity of hepatocellular carcinoma (HCC) treated by TACE and that of the surrounding liver. Thirteen patients with HCC were studied retrospectively. CT and MRI scans were performed both before and 3 months after TACE. The CT scan was performed to check whether embolized nodules contained lipiodol and how lipiodol was distributed within them. In addition, eight patients were examined prospectively within 7 days after TACE. In these patients a CT scan was performed to see how lipiodol was distributed in the neoplastic nodules and in normal hepatic parenchyma. In the first group of patients the contrast-to-noise (C/N) ratio on T1-weighted (T1W) images and the T2 relaxation time on T2-weighted (T2W) images were calculated for both neoplasm and surrounding liver. In the second group of patients we also measured the signal intensity of non-neoplastic liver that was either permeated or not permeated by lipiodol. The data were analysed with Wilcoxon's test. On T1W images we observed that the retention of lipiodol increased the C/N ratio in all the tumours studied within 1 week after TACE. In the patients studied 3 months after TACE the C/N ratio was not significantly increased. On T2W images lipiodol retention did not change tumour signal intensity. The iodized oil did not change the signal intensity of the liver surrounding the tumour, in comparison with the liver not permeated by lipiodol, on either T1W or T2W images. The results indicate that lipiodol does not modify the signal intensity in non-neoplastic hepatic parenchyma in which it is deposited; after 3 months it does not significantly affect the signal of the tumours that accumulated it. Lipiodol produces a high signal on T1W images over the first few days following TACE in those tumours in which it is deposited.

Aged↗
PubMed1997

Attenuation characteristics and application of gadolinium-DTPA in fast helical computed tomography.

RATIONALE AND OBJECTIVES: The computed tomography (CT) attenuation characteristics of gadolinium (Gd)-DTPA have been analyzed both in vitro and in vivo to evaluate the possibility of its substitution for iodine in patients with contraindications for iodine utilization. METHODS: In vitro attenuation values of Gd-DTPA were measured relative to those of iodine under variation of concentration, voltage, preattenuation, and beam hardening. In vivo iodine attenuation values were obtained for different injection rates (3.0 mL/second and 4.5 mL/second) to calculate the attenuation values of 0.5 molar Gd-DTPA to be expected in vivo by the help of the previously obtained attenuation-concentration curves. Subsequently, CT enhancement after an injection of 0.3 mmol/kg body weight Gd-DTPA was evaluated in five patients with contraindications for iodine administration. RESULTS: The injection of a 0.7 molar Gd-DTPA solution at a flow rate of 4.5 mL/second was calculated to be equivalent to that of 2.36 molar iodine at a flow rate of 3 mL/ second. Sufficient enhancement for diagnosis of dissections/ aneurysms of arterial vessels could be achieved. Both arterial and venous cervical or thoracic vessels could be enhanced to 100 Hounsfield units with a bolus injection. In contrast to the thyroid gland, the parenchyma of the liver and the kidney was not sufficiently enhanced. CONCLUSIONS: Gadolinium-DTPA is more effective than iodine in x-ray attenuation; however, its present concentration of 0.5 molar and permitted dose of 0.3 mmol/kg body weight are insufficient to provide parenchymal enhancement with CT. The visualization of arterial vessels appears possible with gadolinium enhanced CT but requires optimal timing and fast scanning capabilities.

Aortic Dissection↗
PubMed1997

Mortality of plastic-ware workers exposed to radiofrequencies.

The mortality experience of a cohort of Italian plastic-ware workers exposed to radiofrequency (RF)-electromagnetic fields generated by dielectric heat sealers was investigated. Follow-up extended from 1962 to 1992. The standardised mortality ratio (SMR) analysis was restricted to 481 women workers, representing 78% of the total person-years at risk. Mortality from malignant neoplasms was slightly elevated, and increased risks of leukemia and accidents were detected. The all-cancer SMR was higher among women employed in the sealing department, where exposure to RF occurred, than in the whole cohort. This study raises interest in a possible association between exposure to RF radiation and cancer risk. However, the study power was very small, and the possible confounding effects of exposure to solvents and vinyl chloride monomer (VCM) could not be ruled out. The hypothesis of an increased risk of cancer after radiofrequency exposure should be further explored by means of analytical studies characterised by adequate power and more accurate exposure assessment.

Adolescent↗
PubMed1996

Type of estrogen receptor determines response to antiestrogen therapy.

Failure of tamoxifen treatment for unresectable hepatocellular carcinomas (HCCs) might be caused by variant estrogen receptors (ERs) in some of these tumors. We therefore planned a study in which antihormonal therapy was done with 80 mg/day tamoxifen or 160 mg/day megestrol according to the presence of wild-type or exon 5-deleted variant ER transcripts. Growth rate (evaluated by MRI) of HCCs characterized by variant ER transcripts was 4 times more rapid than that of HCCs with wild-type ERs. Tumor volume in all patients with wild-type ERs was halved after 9 months of tamoxifen treatment, whereas megestrol in patients with variant ERs only slowed down tumor growth. Choosing antihormonal treatment according to the presence of wild-type or variant ERs in the tumor definitely improves the response rate to tamoxifen; in patients with tumors bearing variant ERs, megestrol causes only a temporary inhibition of tumor growth.

Adult↗
PubMed1996

Local excision and external beam radiotherapy in early rectal cancer.

PURPOSE: To assess the local control and survival of local excision and postoperative radiation in patients with early stage rectal cancer. METHODS AND MATERIALS: From 1980 to 1992, 21 patients with clinical stage T1-2NxM0 adenocarcinoma of the middle and lower rectum were treated with transanal excision and postoperative external beam radiotherapy (44.6 Gy). The pathologic T stages were: 9 T1 (43%) and 12 T2 (57%). One patient had unassessable resection margins. The median follow-up was 54 months (range: 18-128 months). RESULTS: The actuarial local recurrence-free survival at 5 years was 85.2%, and the overall survival at 5 years was 80.6%. One patient developed a local recurrence and distant metastases at 22 months, and two patients had local recurrence at 11 and 15 months, respectively; both had abdomino-perineal resection (APR) and one remained free of disease 16 months after APR. The incidence of Grade 3 diarrhea was 5%. Sphincter function was good to excellent in the 18 patients with local control. No patients developed clinical evidence of pelvic lymph node recurrence. CONCLUSION: These results are similar to other published series and suggest that this approach is feasible in selected patients with T1-2NxM0 rectal cancer and results in good long-term control of the disease.

Adenocarcinoma↗
PubMed1996

[Magnetic resonance of the brachial plexus: anatomy and study technique].

Brachial plexopathies are a common diagnostic problem: conventional imaging techniques can be useful in the detection of associated conditions (Pancoast tumors, first rib or clavicle fractures, etc.) but they cannot visualize brachial plexus structures directly. Also Computed Tomography (CT) is limited in the study of the retroclavicular region because of the artifacts due to the presence of the humeral heads in the slice. CT myelography exhibits very high accuracy in posttraumatic brachial plexopathies but fails to reveal the postganglionic plexus. In contrast, Magnetic Resonance Imaging (MRI) allows the direct detection of the brachial plexus, from spine to axilla, thanks to its multiplanarity and high contrast resolution. However, MR images are so rich in anatomical details (particularly on the oblique planes) that sometimes they become very difficult to interpret. To better define the anatomical relationships of the brachial plexus and to assess the best planes to study its different portions, 9 healthy volunteers were examined with MRI and MR images were compared with anatomical drawings and frozen cadaver sections. MRI depicts the brachial plexus from its origin to the axilla, but none of the investigated planes is sufficient, alone, to study the whole plexus adequately. The paraganglionic portion is clearly depicted on oblique sagittal images, while coronal and sagittal images are more useful for primary trunks and spinal nerves; the distal portion is perfectly visualized on sagittal images. Thus, we conclude that different examination protocols are necessary for every specific plexus portion, which means that brachial plexus MRI must be performed to try to solve a specific question by the orthopedic surgeon or the clinician.

Brachial Plexus↗
PubMed1996

[Liver metastasis from carcinoid: diagnostic imaging].

Our study was aimed at describing the diagnostic imaging patterns of carcinoid liver metastases. Six patients with liver metastases secondary to carcinoid tumor were examined. The metastases were histologically proved in each patient. All patients were examined with ultrasonography (US), Computed Tomography (CT), Magnetic Resonance Imaging (MRI) and Digital Subtraction Angiography (DSA). All patients were treated with transcatheter embolization of liver metastases. Diagnostic imaging methods showed ten to many dozen metastases in each patient. Tumor size ranged 0.5 to 14 cm. US showed hypoechoic, hyperechoic and isoechoic carcinoid liver metastases with a hypoechoic halo. Large lesions had anechoic central areas due to colliquative necrosis. Hypoechoic patterns were the most frequent ones. Precontrast CT showed hypodense metastases; very small lesions were isodense relative to surrounding liver. CT during contrast agent injection showed that the metastases were hyperdense in the arterial phase; contrast enhancement was poorer in the portal phase. Large lesions showed a hypodense central area due to necrosis which remained hypodense in the late phase. The metastases were hypointense on T1-weighted and hyperintense on T2-weighted MR images. Gradient echo dynamic imaging with Gd-DTPA showed high-signal metastases in the arterial phase and lower signal intensity in the portal phase. DSA, an essential exam before embolization, showed tortuous and elongated intra- and extrahepatic arteries and tumor neovascularization with no malignant abnormalities. In the capillary phase, tumor uptake and inhomogeneous hypervascular patterns were shown. Portal veins were only displaced and compressed, but never infiltrated by the metastases. All the techniques we used contributed to assess liver involvement by carcinoid metastases. DSA must be used only before treatment; both CT and MRI showed the hypervascular patterns of the metastases, but no technique could predict their nature.

Adult↗
PubMed1995

Guidelines for the use of zidovudine in pregnant women with HIV infection.

Zidovudine therapy seems to be effective for reducing vertical transmission of HIV infection and preventing paediatric AIDS. Besides those cases in which it is indicated, zidovudine plays an important role in safeguarding maternal well-being. Even though no data indicating teratogenic effect of this drug exist, its use during the first trimester should be limited to those cases where it is absolutely indicated. All undergoing this therapy should be informed that no information regarding the long term effects of this drug are available yet. Further controlled studies are necessary if this drug is to be used in those cases where it could actually be of benefit.

Female↗
PubMed1995

[Comparative evaluation of ultrasonography, computerized tomography, angiography and lipiodol CT in defining extent of hepatocarcinoma. A multicenter study].

The authors report the results of a multicentric trial on hepatocellular carcinoma (HCC) patients, whose lesions were confirmed with biopsy or by high (> 400 ng/ml) alpha-fetoprotein levels. The series consisted of 149 patients examined in 8 different centers and submitted to ultrasonography (US), Computed Tomography (CT) before and after contrast agent administration, angiography and Lipiodol CT. According to lesion size and number, the patients were divided with each imaging modality into three groups: a) group 1: unifocal HCC < 5 cm diameter; b) group 2: multifocal HCC with 2-3 nodules and/or tumor mass < 80 ml; c) multifocal HCC with more than 3 nodules (with total tumor mass not exceeding 40% of liver volume) or with total tumor mass > 80 ml. In 77 patients all the examinations were available for comparison. US and CT diagnosed more patients as belonging to group 1 than angiography and Lipiodol CT, while more patients were classified as groups 2 and 3 with angiography and Lipiodol CT, meaning that US and CT may understage some HCC cases (about 15%) because they show a lower number of nodules. This observation was confirmed by the direct comparison between US and Lipiodol CT (in 114 patients), CT and Lipiodol CT (in 103 patients) and angiography and Lipiodol CT (in 116 patients). US and Lipiodol CT were in disagreement in 18 cases, CT and Lipiodol CT in 16 cases and angiography and Lipiodol CT in 13 cases. In most of these cases, Lipiodol CT showed more lesions than the other techniques. The size of the undetected lesions was small, ranging few mm to 2 cm in nearly all cases. To conclude, the results of this multicentric trial show that Lipiodol CT is a fundamental tool to evaluate HCC extent. In contrast, conventional CT appeared not to add any significant piece of information and can therefore be excluded from the diagnostic protocol of HCC.

Angiography↗