Biomedical subjects

M Rossi

Publications and source records attributed to M Rossi.

At least 739 records · Page 41Linked to original sources

PubMedDate not supplied

Multidetector CT and virtual endoscopy in the evaluation of the esophagus.

In this prospective study, we assessed the diagnostic capabilities of multidetector computed tomography (CT) in various esophageal pathologic conditions. Thirty-three patients underwent a multidetector CT study after esophageal distention by means of effervescent powder administered after induction of pharmacologic esophageal hypotonia. All acquired images were post-processed with two- and three-dimensional software tools. The CT data were compared with the results of conventional radiology (33), endoscopy (28), endoscopy ultrasonography (14), or surgery (14). Follow-up ranged between 4 and 15 months. Esophageal distention in the upper and middle thirds was classified as "good" in 32 of 33 cases (97%); in the lower third, esophageal distention was "good" in 21 of 33 cases (64%). Final diagnoses were leiomyoma (six cases), squamous cell carcinoma (six), adenocarcinoma (four), esophageal infiltration by thyroid cancer (two), benign polyposis (two), chronic esophagitis (five), post-sclerotherapy stenosis (one), no abnormalities (seven). When good distention was achieved, the thickness of unaffected esophageal wall was less than 3 mm (range, 1.5-2.4 mm; mean, 1.9 mm). Pathologic wall thickening was observed in 25 of 33 cases (76%), with values ranging between 3.6 and 36 mm (mean, 9.6 mm). Spiral CT demonstrated 21 true positive cases, and seven true negative cases. There were four false negative cases and one false positive case. Sensitivity was 84%, specificity was 87%, diagnostic accuracy was 85%, positive predictive value was 95%, and negative predictive value was 64%. Evaluation of the esophagus with multidetector CT is a promising technique and easy to use, allowing panoramic exploration, virtual endoluminal visualization, accurate longitudinal and axial evaluations, and simultaneous evaluation of T and N parameters.

Esophageal Diseases↗

PubMedDate not supplied

Clinical experience with covered wallstents for biliary malignancies: 23-month follow-Up.

PURPOSE: To evaluate the effectiveness of partially covered metallic Wallstents to prevent tumoral ingrowth in patients with neoplastic obstruction of the biliary tract. METHODS: Twenty-one patients with malignant obstructive jaundice have been treated with Wallstents partially covered with a polyurethane polymer. In total, 36 covered stents (8 and 10 mm in diameter, 70 and 90 mm long) were deployed. All the stents were free from covering at both ends. RESULTS: Jaundice was successfully treated in 100% of cases. There were no problems related to the releasing system during stent positioning, no major complications, and no incompatibility reactions to the materials composing the endoprostheses. At 23-month follow-up, 6 patients are still alive and 15 are dead; of these 15 patients, 11 died in the first 6 months and the last 4 died between 6 and 23 months. Seven patients had an obstructed stent; in four of these, cholangioscopy showed the presence of tumoral ingrowth and in one it showed necrotic tissue with biliary pigments and inflammatory cells. No biopsy specimen was obtained in the remaining two patients with stent obstruction. The follow-up, ranging from 7 to 23 months, showed a primary patency of 46.8% and 24.6% and an assisted patency of 66.3% and 59% at 6 months and 23 months, respectively. CONCLUSIONS: Covered metallic stents are effective and may produce improved survival in patients with malignant biliary obstruction (27. 8% at 23 months). Stent patency, however, is similar to that of uncovered stents. Modifications in the design of the covering membrane may reduce stent obstruction resulting from disruption of the plastic covering.

Aged↗

PubMedDate not supplied

Characterization of the plasmid pMB1 from Bifidobacterium longum and its use for shuttle vector construction.

The nucleotide sequence of the 1847-bp Bifidobacterium longum B2577 cryptic plasmid pMB1 was determined. The plasmid had a G+C content of 62.0%, and contained two open reading frames, orf1 and orf2, likely arranged in an operon. The proteins encoded by orf1 and orf2 show the highest degree of similarity with similarly arranged peptide sequences translated from Corynebacterium glutamicum pXZ10142 and Mycobacterium fortuitum pAL5000 plasmids. Recombinant plasmids containing the pMB1 replicon were able to replicate in Bifidobacterium animalis MB209. The successful transformation of this strain with pMB1-based plasmids facilitated characterization of this replicon, results of which showed that both orf1 and orf2 are necessary for plasmid replication. A family of new Escherichia coli-B. animalis shuttle plasmids, based on the pMB1 replicon and expressing a cat and an ery gene, was constructed.

Amino Acid Sequence↗

PubMedDate not supplied

Ethical considerations on kidney transplantation from living donors.

Kidney transplantation from living donors is widely performed all over the world. Living nephrectomy for transplantation has no direct advantage for the donor other than increased self-esteem, but at least remains an extremely safe procedure, with a worldwide overall mortality rate of 0.03%. This theoretical risk to the donor seems to be justified by the socioeconomic advantages and increased quality of life of the recipient, especially in selected cases, such as pediatric patients, when living donor kidney transplantation can be performed in a preuremic phase, avoiding the psychological and physical stress of dialysis, which in children is not well tolerated and cannot prevent retarded growth. According to the Ethical Council of the Transplantation Society, commercialism must be prevented, not only for ethical but also medical reasons. The risks are too high not only for the donors, but also for the recipients, as a consequence of poor donor screening and evaluation with consequent transmission of human immunodeficiency virus or other infectious agents, as well as inappropriate medical and surgical management of donors and also of recipients, who are often discharged too early. Most public or private insurance companies are considering kidney donation a safe procedure without long-term impairment and, therefore, do not increase the premium, whereas recipient insurance of course should cover hospital fees for the donors. "Rewarded gifting" or other financial incentives to compensate for the inconvenience and loss of income related to the donation are not advisable, at least in our opinion. Our center does not perform anonymous living organ donation or "cross-over" transplantation.

Family↗

PubMedDate not supplied

Predictive factors of outcome after liver transplantation in patients with cirrhosis and hepatocellular carcinoma.

Studies to define the optimal upper limits of tumor size and number as predictors of outcome after orthotopic liver transplantation (OLT) have yielded conflicting results. We analyzed 72 patients with cirrhosis and hepatocellular carcinoma (HCC) who underwent OLT over a 12-year period in a single center. Predictive factors for survival and tumor recurrence, according to the Milan criteria, were also examined. Our cohort included 60 men and 12 women of mean age 54 +/- 8 years and mean follow-up of 40 +/- 39 months. Origin of cirrhosis was postviral in 70% and Child class B or C in two thirds of patients. HCC was multifocal in 61%; about one fifth of patients had micro- or macrovascular involvement or positive nodes upon histologic examination. The cumulative size of the lesions was <3 cm in 17 patients; >3 to < or =5 cm in 28 patients; >5 to < or =8 cm in 14 patients; and >8 cm in 13 patients. According to the number and size of tumor nodules, 49 patients met the Milan criteria. During follow-up 25 patients died, 13 due to tumor recurrence. The 1- and 2-year survivals were 90% and 85% for patients who met the Milan criteria versus 57% and 51% for patients exceeding those limits (P = .006). A cumulative tumor size >8 cm was predictive of survival and tumor recurrence upon multivariate analysis. The adoption of Milan criteria for selection of cirrhotic patients has improved survival and reduced the rate of tumor recurrence. The evaluation of cumulative tumor size might further improve patient selection.

Carcinoma, Hepatocellular↗

PubMedDate not supplied

Molecular adsorbent recirculating system treatment for acute hepatic failure in patients with hepatitis B undergoing chemotherapy for non-Hodgkin's lymphoma.

Hepatitis B virus (HBV) is a serious cause of morbidity and mortality in hepatitis B surface (HBsAg) antigen-positive patients treated with chemotherapy. Because the hepatitis is related to HBV virological reactivation, application of effective antiviral therapy, such as Lamivudine, has been attempted. Despite the use of these antiviral agents at the time of clinical hepatitis, some HBsAg-positive patients still develop hepatic failure and die. We used the Molecular Adsorbent Recirculating System (MARS) (MARS Monitor; Teraklin AG, Rostock, Germany) to treat 5 HBsAg-positive lymphoma patients with acute hepatic failure due to chemotherapy despite lamivudine treatment. Before and after each treatment we monitored the parameters of neurological status (EEG, cerebral CT and Glasgow coma score), hemodynamic parameters, acid-base equilibrium and blood gases as well as hepatic and renal function. The inclusion criteria were these of the King's College Hospital. Statistical analysis by Student t method showed significant results (P < .01). Three of 5 patients are alive without signs of reactivation of viral or hematological diseases at 1 year follow-up. The 2 patients died because MARS treatment was started too late, with Glascow coma score grade IV, hemodynamic instability, and mechanical ventilator assistance. Despite the limited number of cases, we believe that MARS can be applied to patients with a high tolerance and yield good results, but the treatment has to start at the first signs of hepatic failure.

Adult↗

PubMedDate not supplied

One hundred sixteen cases of acute liver failure treated with MARS.

The various definitions of acute liver failure do not accurately reflect the differences in clinical signs and prognosis. Liver support devices to improve the clinical condition before liver transplantation (LT) were used in 13 patients with primary nonfunction, 24 with fulminant hepatitis, 17 were affected by delayed nonfunction, and 56 of acute on chronic hepatic failure. The average age of these patients was 41.8 years. The average number of applications of molecular absorbing recirculating system (MARS) was about 6 (range: 1-24). The mean length of application was about 9 hours (range: 8-20). MARS treatment was carried out in HLF patients with continuous acute-on-chronic hepatic failure dialisate flow similar to continuous veno venus hemofiltration (CVVH), albumin flow < 20% of hematic flow, heparin 5/10 UI/kg. In acute on chronic hepatic failure (AoCHF) patients, 6- to 11-hour (average 8.5) treatments were performed for a minimum of three treatments. The majority of patients were treated in the intensive care unit (ICU). Laboratory results were also monitored and showed progressive modification: bilirubin (before treatment 22.37 +/- 11.6 mg/dL, after treatment 11.36 +/- 7.5 mg/dL) and ammonium (before treatment 238.2 +/- 19 microg/dL, after treatment 115.4 +/- 12 microg/dL) showed significant change (P < .01). Lactates (before treatment 3.48 +/- 1.3 mmol/L, after treatment 1.76 +/- 1.1 mmol/L) and creatinine (before treatment 2.36 +/- 0.18 mg/dL, after treatment 1.26 +/- 0.67 mg/dL) also showed significant changes (P < .02 and P < .04). Glasgow Coma Score (GCS) went from 8.6 +/- 1.4 to 11.9 +/- 3.9 (P < .05). The mean middle cerebral artery flow (V media) went from 46 cm/s/26-59) to 73 cm/s (52-106) representing decreased cerebral edema, a difference that was not significant. INR scores (before treatment 2.4 after treatment 1.8) also showed no significant change. The MARS can be applied with tolerability for long periods for patients with PDF and FH as a bridge to transplant. In patients with PDF, it is used for a waiting recovery of the transplanted organ. Therefore MARS can also limit the necessity to perform further transplants.

Adult↗

PubMedDate not supplied