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L Balestreri

Publications and source records attributed to L Balestreri.

15 recordsLinked to original sources
PubMed2000

HINT predictive analysis of binding between retinol binding protein and hydrophobic ligands.

The interaction between the retinol binding protein and four ligands was evaluated using HINT, a software based on experimental LogP values of individual atoms. A satisfactory correlation was found between the HINT scores and the experimental dissociation constants of three of the ligands, fenretinide, N-ethylretinamide and all-trans retinol, despite their hydrophobic nature. A prediction is made for the binding affinity of the fourth ligand, axerophtene, not yet determined in solution.

Algorithms↗
PubMed2000

Raysum reconstruction algorithm in MR cholangiopancreatography.

Magnetic resonance cholangiopancreatography (MRCP) is a new, non-invasive imaging technique for the visualization of the biliary ducts. The presence of stones within the choledocus is easily detectable in source images. However, three-dimensional reconstructions using the maximum intensity pixel (or projection) algorithm (MIP) fail to reproduce accurately the eventual presence of filling defects or parietal irregularities due to biliary stones. We used the Raysum algorithm in addition to the MIP in evaluating MRCPs of twelve patients with known choledocolithiasis. A visualization of the stones was obtained in nine (75%) patients by using the Raysum while visualization was obtained in one patient by using MIP. No additional sequences are required, and the post-processing time takes only a few seconds. The Raysum reconstruction can be successfully associated to the MIP in the three-dimensional evaluation of biliary stones in MRCP.

Adult↗
PubMed1997

Central venous thrombosis: an early and frequent complication in cancer patients bearing long-term silastic catheter. A prospective study.

Studies on catheter-related central venous thrombosis (CRCVT) have been focused mainly on clinically evident CRCVT due to occlusive thrombi, underestimating therefore the actual thrombosis prevalence. This prospective study was aimed at evaluating prevalence, timing and evolution of thrombosis, and identifying involved veins and risk factors in cancer patients (pts) undergoing percutaneous subclavian central venous catheterization (CVC) for chemotherapy, parenteral nutrition or both. We enrolled 127 consecutive pts requiring partially or totally implanted central venous silastic catheters. The study protocol included peripheral phlebography (P) at day 8, 30 and every two months following CVC and/or when clinically indicated, along with peripheral and pullout P on catheter withdrawal. A quantitative scale was developed to evaluate thrombus grading in subclavian, innominate and cava veins. Age, sex, coagulation profile tumor histotype, metastases, therapy, catheter type, and catheter insertion side were also investigated. Only pts who underwent at least two P were evaluated, and chi 2 test was adopted for statistical analysis. Altogether, 95 pts were evaluable. CRCVT was observed in 63/95 (66%) pts. At day 8, 30 and 105 (representing the median days in which first, second and last P were performed) CRCVT was evidenced in 64%, 65% and 66% of the pts, respectively. Thrombus grading did not differ among first, second and last P. CRCVT was symptomatic in 4/63 (6%) pts. Thrombosis prevalence was higher in subclavian (97%) with respect to innominate (60%) or cava (13%) veins (p < 0.001). Thrombosis was higher in left subclavian catheters (14/16; 87.5%) than in right ones (49/79; 62%), p < 0.01. No associations were established between CRCVT and other investigated parameters. Our data show a very high actual frequency of CRCVT in cancer pts, and emphasize that first days following CVC are at the highest risk for CRCVT development. Based on our results, a study on short-term antithrombotic prophylaxis in cancer pts requiring CVC is warranted. Finally, our data indicate that left subclavian vein catheterization represents a risk factor for CRCVT.

Adolescent↗
PubMed1997

Solitary meningeal recurrence in a patient with transitional cell carcinoma of the bladder with locally bulky disease at presentation.

Patients with locally advanced transitional cell carcinoma (TCC) of the bladder are at high risk for systemic relapse, with liver, bone and lung being the commonest sites of metastases. We report the case of a 52-year-old woman with a solitary meningeal relapse, a rare site of recurrence, after 8 months of complete remission obtained with M-VEC for locally advanced TCC of the bladder. We speculate on the likely risk factors related to this unusual site of recurrence.

Carcinoma, Transitional Cell↗
PubMed1997

Single-needle celiac plexus block: is needle tip position critical in patients with no regional anatomic distortions?

BACKGROUND: The "single-needle" celiac plexus block is becoming a popular technique. Despite different approaches and methods used to place the needle, the success of the block depends on adequate spread of the injectate in the celiac area. In the present retrospective study, the influence of needle tip position in relation to the celiac artery on injectate spread was evaluated. METHODS: Among 138 cancer patients subjected, via an anterior approach, to computed tomography (CT)-guided single-needle neurolytic celiac plexus block, a radiologist, blinded to the aim of the study, retrospectively selected 53 cases with normal anatomy of the celiac area as judged by CT. The decision was based on images obtained before the block. Patients were then classified into either group A (29 patients), in whom the needle tip was caudad to the celiac artery, and group B (24 patients), in whom it was cephalad. To evaluate CT patterns of neurolytic (mixed with contrast) spread, the celiac area was divided on the frontal plane into four quadrants: upper right and left and lower right and left, as related to the celiac artery. Patient assessments by visual analog scale were reviewed to evaluate the degree of pain relief. Pain relief 30 days after block was judged as long-lasting. The patterns of contrast spread in relation to the needle position and pain relief according to the number of quadrants with contrast were analyzed. RESULTS: The percentage of cases with four quadrants with contrast was higher when the needle tip was cephalad (58%, group B) than when it was caudad (14%, group A) to the celiac artery (P < 0.01). The percentage of patients with four and three quadrants with contrast was also higher in group B at 79% than in group A at 38% (P < 0.01). A significant difference in long-lasting pain relief was observed between patients with four quadrants with contrast (18 of 18, 100%; 95% confidence interval [CI], 81-100%) and patients with three quadrants with contrast (5 of 12, 42%; 95% CI, 15-72%) (P < 0.01). No patients showing two or one quadrant with contrast had long-lasting pain relief. CONCLUSIONS: These findings suggest that, when the celiac area is free from anatomic distortions, and the single-needle neurolytic celiac plexus block technique is used, the needle tip should be positioned cephalad to the celiac artery to achieve a wider neurolytic spread. It also appears that only a complete (four quadrants) neurolytic spread in the celiac area can guarantee long-lasting analgesia.

Adult↗
PubMed1997

HIV-associated human herpesvirus 8-positive primary lymphomatous effusions: radiologic findings in six patients.

PURPOSE: To define the imaging features of body cavity-based lymphoma (BCBL) related to the acquired immunodeficiency syndrome. This is a peculiar type of non-Hodgkin lymphoma harboring infection by human herpesvirus 8 (HHV-8) and displaying a peculiar tropism for the serous body cavities. MATERIALS AND METHODS: At diagnosis of BCBL, six consecutive patients were investigated with radiography of the chest and conventional computed tomography (CT) of the chest and abdomen. For all patients, clinical features and results of biologic characterization of the lymphoma were also available. RESULTS: In all patients, chest radiographs displayed bilateral or unilateral pleural effusion in the absence of parenchymal opacities or mediastinal enlargement. CT scans confirmed chest radiographic findings and revealed a slight thickening of the parietal pleura in all patients and a pericardial thickening in four patients. CT also depicted pericardial and abdominal effusions in five and two patients, respectively, in the absence of solid tumor masses or parenchymal abnormalities. CONCLUSION: BCBL must be included among the differential diagnoses of serous effusions detected radiologically in individuals infected with the human immunodeficiency virus (HIV). Since the combination of serous effusion, slight serosal thickening, and absence of solid masses is compatible with, though not specific for, BCBL in the context of HIV infection, radiologic findings need to be complemented by a detailed biologic and virologic characterization of tumor cells.

Adult↗
PubMed1997

[The presentation of a picture archiving and communication system (PACS) and the initial experiences with its use].

INTRODUCTION: The use of computers has yielded new diagnostic techniques (US, CT, MRI and computed radiography) that can successfully replace conventional film in data acquisition, image display and image interpretation. Thanks to the Picture Archiving and Communication System (PACS), we can now manage the whole of diagnostic data because the images are acquired, coupled to the patient data stored in the Radiology Information System (RIS), sent to display workstations and finally sent to the archives. PURPOSE: To present the configuration and functions of a new PACS used in radiology and nuclear medicine departments and to evaluate its efficacy one year after implementation. Particular attention is paid to the objective difficulties radiologists found in approaching the system. RESULTS: Secretarial work reduction and a more rational archiving organization are two of the advantages of automation. PACS permits rapid image display, retrieval nd archiving for both scientific and statistical purposes; however, its correct use is hindered by a series of problems, namely: a) reluctance to use PACS by many members of the medical staff, due to the complexity of its procedures; b) lack of panoramicity on the display monitor in multi-image examinations and c) underuse of viewing workstations in several wards of our institution due to lack of know-how. CONCLUSIONS: Although the use of PACS has improved the workload management in our departments, the system still needs to be customized to the radiologist to optimize its use. Workstations must be user-friendly, with simultaneous display of more images. On the other hand, radiologists need to expand their knowledge of new techniques, thus modifying obsolete working procedures.

Computer Systems↗
PubMed1995

Antithrombin III deficiency as a risk factor for catheter-related central vein thrombosis in cancer patients.

The fibrin sleeve of venous catheters (VC) and parietal thrombi represent frequent and dangerous side-effects of central venous catheterization (CVC), due to the risk of embolism. Reduced levels of coagulation clotting factors inhibitors (such as Antithrombin III) are known to be associated with increased thrombogenic risk. The aim of this study was to evaluate the role of Antithrombin III (AT III) deficiency as a risk factor for thrombosis in cancer patients undergoing CVC. The study groups included patients with a reduced AT III activity (< 70%, 20 consecutive patients) and with normal AT III values (> 70%, 20 randomly selected patients), requiring a VC for chemotherapy and/or total parenteral nutrition. The study protocol included evaluation of Hb, PLTs, PT (INR), aPTT, Fibrinogen and AT III at days 0, 1, 3 and 8 after CVC and upon VC removal. Peripheral and pullout phlebographies were performed in all patients on catheter withdrawal. A quantitative scale was developed to evaluate both VC and parietal thrombus degree in each catheter-containing venous segment (subclavian, innominate, superior vena cava); the sum of the mean values was defined as overall thrombus. The average VC dwelling time was similar in both groups. There were no significant differences in Hb, PLTs, PT (INR), aPTT, Fibrinogen and in the remaining parameters of the study between the two groups. The group with AT III deficiency presented a higher degree of both parietal (p < 0.05) and overall thrombus (p < 0.02). Data showed a higher severity of CVC-related thrombosis in patients with AT III deficiency than in the control group. Further studies are needed to evaluate whether the therapeutically-induced normalization of AT III levels can reduce the thrombosis degree.

Adult↗
PubMed1995

Central venous catheter-related thrombosis in clinically asymptomatic oncologic patients: a phlebographic study.

Fifty-seven oncologic patients with short- or long-term central venous catheters (CVCs) and without clinical signs of axillary-subclavian thrombosis were evaluated phlebographically. Different degrees of incomplete thrombosis were found in 26 patients (45.5%) and complete thrombosis, clinically silent, was found in six patients (10.5%). A fibrin sleeve around the CVC was radiologically demonstrated in 45 (78%) patients, 21 of them (46%) with negative standard venogram. Only in four patients there was no evidence of fibrin sleeve or parietal thrombosis. There were no significant differences between patients with long-term and short-term CVCs. We conclude that parietal thrombosis of the axillary-subclavian veins is a frequent event, even if there is no clinical evidence of flow obstruction and we confirm in vivo that a fibrin coating of the CVCs is present in the majority of the cases.

Adolescent↗
PubMed1993

[Urinary calculi in an intestinal loop used for ureteral substitution. A case report].

The authors report the case of large urinary calculi formed inside the ileal conduit diversion in a patient who underwent radical surgery for an ovarian carcinoma involving the right ureter. Two ureter stents were left to ensure drainage and were endoscopically removed after six months. Renal function and ureteral canalization were normal. However, because of a knot in the proximal end of stents, a piece 5 cm-long-was left inside the diversion. After six months the patient developed recurrent renal colics: plain abdomen X-ray and urography showed a large urinary stone around the stents fragment and several smaller stones nearby. They all were removed surgically. The pathogenesis of such complications was considered: even though the slow flux of urine in the diversion, the abnormal mucus production from the ileal mucosa and the excessive and chronic bicarbonate loss played an important role in the developing of urinary calculi, the authors believe that in this case the main responsible for the stone formation was the foreign body in the urinary diversion.

Adult↗
PubMed1992

[Radiologic characteristics of the thorax during therapy with interleukin-2].

Interleukin-2 is a glycoprotein physiologically produced by human lymphocytes which is capable of mediating some still unknown immunologic reactions. In vitro, interleukin-2 was seen to induce a lytic reaction against tumor cells through the activation of a cytolytic system of natural killer cells. If administered to man in heavy doses, it causes a clinical response in the treatment of metastases from melanoma and renal cell carcinoma in 20-40% of cases. However, the clinical use of the drug, in therapeutic doses, is prevented by the occurrence of several side-effects, the major one being increased permeability of alveolar vessels with capillary leak and interstitial pulmonary edema (Vascular Leak Syndrome in the English literature). Thus, this work was aimed at evaluating chest radiographs during interleukin-2 treatment to detect, in the pulmonary district, the early stages of the vascular leak syndrome--i.e., pulmonary edema, pleural and pericardial effusions. Forty-three patients had been treated for metastases from renal cell carcinoma and melanoma November 1989 through September 1991: standard chest radiographs demonstrated 26 cases (60%) of pulmonary edema, 14 cases (32%) of bilateral pleural effusions and 12 cases (27%) of pericardial effusions. Daily chest films of the patients undergoing interleukin-2 therapy allowed the early stage of the vascular leak syndrome to be depicted, thus enabling the physician to use the highest tolerated doses and eventually to stop infusion before marked respiratory distress develops.

Humans↗
PubMedDate not supplied

Calcified gastric cancer--CT findings before and after chemotherapy. Case report and discussion of the pathogenesis of this type of calcification.

Diffuse calcifications in primary gastric cancer are very rare, most of them being found in mucinous adenocarcinoma. We present the CT aspects of a locally advanced gastric cancer, which showed partial response to neo-adjuvant chemotherapy. The pathological features of the surgical specimen after total gastrectomy are also reported and the pathogenesis of the calcifications is discussed.

Adenocarcinoma, Mucinous↗