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A Cavallari

Publications and source records attributed to A Cavallari.

At least 55 records · Page 3Linked to original sources
PubMed1999

Ischemia-reperfusion injury in rat fatty liver: role of nutritional status.

Fatty livers are more sensitive to the deleterious effects of ischemia-reperfusion than normal livers. Nutritional status greatly modulates this injury in normal livers, but its role in the specific setting of fatty liver is unknown. This study aimed to determine the effect of nutritional status on warm ischemia-reperfusion injury in rat fatty livers. Fed and fasted rats with normal or fatty liver induced by a choline deficient diet underwent 1 hour of lobar ischemia and reperfusion. Rat survival was determined for 7 days. Serum transaminases, liver histology and cell ultrastructure were assessed before and after ischemia, and at 30 minutes, 2 hours, 8 hours, and 24 hours after reperfusion. Survival was also determined in fatty fasted rats supplemented with glucose before surgery. The preischemic hepatic glycogen was measured in all groups. Whereas survival was similar in fasted and fed rats with normal liver (90% vs. 100%), fasting dramatically reduced survival in rats with fatty liver (14% vs. 64%, P <.01). Accordingly, fasting and fatty degeneration had a synergistic effect in exacerbating liver injury. Mitochondrial damage was a predominant feature of ultrastructural hepatocyte injury in fasted fatty livers. Glucose supplementation partially prevented the fasting-induced depletion of glycogen and improved the 7-day rat survival to 45%. These data indicate that rat fatty livers exposed to normothermic ischemia-reperfusion injury are much more sensitive to fasting than histologically normal livers. Because glucose supplementation improves both the hepatic glycogen stores and the rat survival, a nutritional repletion procedure may be part of a treatment strategy aimed to prevent ischemia-reperfusion injury in fatty livers.

Alanine Transaminase↗
PubMed1999

Systemic and splanchnic hemodynamic changes after liver transplantation for cirrhosis: a long-term prospective study.

The effect of orthotopic liver transplantation (OLT) on the systemic and splanchnic hemodynamic alterations of cirrhosis is still largely unknown. The aim of this study was to prospectively investigate the long-term changes induced by OLT on several hemodynamic parameters. In 28 patients undergoing OLT for cirrhosis, the following parameters were measured before surgery and subsequently at 6-month intervals (mean follow-up period, 17 months): cardiac index, mean arterial pressure (MAP), heart rate, total peripheral resistance (TPR), portal vein flow velocity and flow volume, spleen size, and Doppler ultrasound resistance or pulsatility indexes (RI or PI) in the: 1) interlobular renal, 2) superior mesenteric, 3) splenic, and 4) hepatic arteries. The same parameters were measured in 10 healthy controls. After OLT, cardiac index and heart rate significantly decreased (P <.01), while MAP and TPR increased (P <.001), so that any significant difference from controls disappeared. Renal RI progressively decreased, achieving a significant reduction (P <.05) to normal values at the 12th month of follow-up. Portal flow velocity and hepatic and splenic RI returned to values not significantly different from controls. Portal flow volume increased over normal values after OLT (P <.001), and SMA PI, lower than normal before OLT, did not show any statistically significant increase thereafter. Spleen size decreased significantly, but persisted to be larger than in controls. In conclusion, systemic, renal, and most, but interestingly not all, splanchnic circulatory alterations of cirrhosis are restored to normal after OLT.

Blood Flow Velocity↗
PubMed1999

Autonomic dysfunction and hyperdynamic circulation in cirrhosis with ascites.

Patients with advanced cirrhosis frequently show hemodynamic abnormalities. Autonomic dysfunction (AD) is also common and, owing to the importance of autonomic function in cardiovascular homeostasis, it may be involved in the pathogenesis of the hyperdynamic circulation. We, therefore, evaluated the hemodynamic status and autonomic function in 30 patients with cirrhosis, most of them with an advanced stage of the disease. Autonomic function was assessed with 7 cardiovascular tests exploring the vagal or sympathetic function. Each test was scored from 1 to 3 (normal, borderline, altered). Cardiac index (CI) was measured by an echocardiogram. Twenty-four (80%) patients showed an AD, this being definite in 14 (47%) patients. A vagal dysfunction (VD) was found in 19 patients (63%), this being definite in 11 patients (37%), and a sympathetic dysfunction (SD) in 7 patients (definite in 3 [10%] patients). The patients with AD showed a faster heart rate (P =.021), lower indicized peripheral vascular resistance (P =.013), and increased CI (P =.004) than patients without AD whereas mean arterial pressure did not differ. Similar results were seen by grouping patients according to the VD. AD score was directly correlated with heart rate (r = 0.53; P =.002) and CI (r = 0.45; P =. 016), and inversely correlated with peripheral vascular resistance (r = 0.46; P =.013). Even closer correlations were found with vagal score. AD (mainly VD) may be involved in the pathogenesis of the hyperdynamic circulatory syndrome of patients with advanced cirrhosis.

Adult↗
PubMed1999

Porcine living liver transplantation using a vascular prosthesis to replace the intrahepatic vena cava.

BACKGROUND: This study aimed to determine whether the porcine model could be adapted to accommodate living donor liver transplantation (LLT). Because the pig hepatic anatomy precludes a standard approach, a study was designed to evaluate the results using a segment of vascular prosthesis to replace the intrahepatic portion of the inferior vena cava (IVC) with establishment of hepatic venous drainage into the graft. METHODS: A total of 10 LLT were performed using 20 pigs. After left hepatectomy, the intrahepatic IVC was replaced with a modified aorto-iliac prosthesis, anastomosing the proximal (aortic limb) to the infradiaphragmatic IVC, one distal iliac limb to infrahepatic IVC and the other (after shortening) to establish hepatic venous drainage after transplant. Conventional venous bypass was used, and no immunosuppressives were administered. RESULTS: All donors survived the 10-day posthepatectomy observation period. Eight of the 10 transplanted pigs survived at least 2 days (mean 7.6 days; range 3-13 days). No evidence of caval graft thrombosis was observed. CONCLUSIONS: Replacement of the recipient intrahepatic IVC by a vascular prosthesis allows to overcome the major technical obstacle which has limited the use of pigs in LLT.

Anastomosis, Surgical↗
PubMed1998

Randomized trial of cyclosporine microemulsion (neoral) versus conventional cyclosporine in liver transplantation: MILTON study. Multicentre International Study in Liver Transplantation of Neoral.

BACKGROUND: The new microemulsion formulation of cyclosporine (Neoral) has been developed in an effort to improve the reliability of drug absorption. The objectives of this study were to assess the efficacy, safety, and tolerability of Neoral compared to the original formulation (Sandimmun) in liver transplant recipients. METHODS: In a double-blind, parallel group study conducted in 28 centers across Europe and the United States, patients receiving primary orthotopic liver allografts were randomized within 24 hr of transplantation, 198 to Neoral and 192 to Sandimmun. Patients with and without T-tube biliary drainage were included. Postoperatively, all patients also received intravenous (i.v.) cyclosporine, together with prednisolone and azathioprine. Antibody induction was excluded. Efficacy measures were rejections, graft failure, patient survival, and the efficacy of the study medication in achieving the desired cyclosporine blood levels. Safety was assessed by reported adverse events, blood pressure, serum creatinine, and other routine laboratory measurements. RESULTS: Kaplan-Meier analyses showed that the Neoral group performed better than the Sandimmun group, with the estimates for patients free of treated rejection and histologically confirmed rejection either showing or approaching statistical significance at the 5% level. By 52 weeks, 5.8% (95% confidence limits: -4.4-15.9%) fewer patients required treatment of acute rejection in the Neoral group. The proportion of patients experiencing at least one treated rejection episode by 2 weeks was 29.8% for Neoral and 43.2% for Sandimmun. For histologically confirmed rejection, these proportions were 32.8% and 44.3%, respectively. The proportion of patients experiencing at least one steroid-resistant rejection was 2.0% for Neoral and 6.3% for Sandimmun at week 2, and 3.0% and 9.9%, respectively, at week 3. All these differences were significant at P<0.05. By 52 weeks, graft failure was 6.3% on Neoral and 11.4% on Sandimmun, with respective patient survival figures of 85.4% and 85.8%. The median duration of the initial episode of i.v. cyclosporine was 4.0 days for Neoral, compared to 6.5 days for Sandimmun (P<0.001). Within the first 2 weeks, a larger percentage of patients in the Neoral group reached the lower target level of cyclosporine (P< or =0.01). The weight-adjusted daily doses of study medication were lower in the Neoral group (median dose: 4.86 vs. 5.42 mg/kg/day, P=0.001), but the blood levels of cyclosporine showed no difference. For those with a T-tube, more of the patients on Neoral remained free of treated rejection throughout the study period (P=0.042, Wilcoxon). By week 2, 44.9% of these patients in the Sandimmun group required treatment for rejection compared to 30.2% in the Neoral group (P=0.007). There was no significant difference between the groups for serum creatinine, blood pressure, other biochemical and hematological variables, or reported adverse events. CONCLUSIONS: In liver transplantation in the normal clinical setting, the pharmacokinetic advantages of Neoral translate into clinical superiority over Sandimmun without a negative impact on safety. Recent data indicate that it is not optimal to use i.v. cyclosporine initially in this type of study, but the benefit was seen despite this. In keeping with the previous pharmacokinetic studies, patients managed by T-tube biliary drainage, and hence with no or limited bile available in the gastrointestinal tract, did particularly well with Neoral.

Adult↗
PubMed1998

Prosthesis jump graft: an unusual arterial reconstruction in liver transplantation.

The authors present a case of arterial jump graft using a number 9 Goretex prosthesis (FEP ringed vascular graft; W.I. Gore Associates Inc.-Delaware, Flagstaff, AZ) with an excellent outcome 3 years after the transplant. The prosthesis was necessary because of the impossibility of using the donor iliac arterial grafts due to the presence of widespread atherosclerotic damage.

Adult↗
PubMed1998

Chemiluminescent real time imaging of post-ischemic oxygen free radicals formation in livers isolated from young and old rats.

Oxygen free radicals generation is a major cause of liver injury during reperfusion. Luminescence analysis has been recently proposed to measure free radical generation by isolated cells or organs, but it allows only global tissue luminescence. Using a special Saticon videocamera with image intensifier we aimed to visualize and localize oxygen free radical generation in isolated perfused livers exposed to an oxydative stress. Livers isolated from rats aged 4 and 30 months were exposed to ischemia/reperfusion; photons emission by the organs was continuously recorded. Lucigenin was utilized as a chemiluminigenic probe to assess superoxide anion generation. In both groups, chemiluminescence was not detectable during ischemia, while it was observed after reperfusion. Photons emission started after few minutes of reperfusion, was maximal after 15-20 min and disappeared within 50-60 min. Chemiluminescence emitted by livers from younger rats however, was significantly higher when compared to chemiluminescence emitted by organs isolated from old rats (0.8 +/- 0.1 vs 0.44 +/- 0.08 photons x 10(5)/s, respectively, after 15 min; p < .01). The superimposition of chemiluminescent and live image permitted to determine the regional production rate and distribution of photons. In conclusion, the age of the rats influences significantly the amount of oxyradicals produced in the liver during post-ischemic reperfusion. The method described, allowing the visualization in real time of oxygen free radicals generation on the surface of isolated intact organs, represents a novel and potent tool for the study of oxidative stress.

Acridines↗
PubMed1998

An appraisal of percutaneous treatment of liver metastases.

Percutaneous treatments, such as ethanol injection and radiofrequency, have been recently proposed for the treatment of liver metastases. The aim of this study was to evaluate the effects of these treatments in a series of 8 patients who subsequently underwent liver resection. These patients had been treated with percutaneous methods between December 1995 and May 1997. In 6 patients, the primary tumor was colonic; in 2 patients, carcinoid; and in 1 patient, ileal leiomyosarcoma. The lesions were all initially small in size (1.5 to 3.5 cm), single in 7 patients, and multiple in 1 patient with a carcinoid tumor. The initial decision for percutaneous treatment had been made on subjective grounds by the radiologists who originally saw the patients. The number of percutaneous treatment sessions ranged from 2 to 21. In all patients, a progression of the disease occurred. Four patients underwent a right hepatectomy; 1 patient, a left lobectomy; 2 patients, a segmentectomy; and 1 patient, a wedge resection. There was no operative mortality in any of these 8 patients. Two patients presented with seeding of the neoplasm on the diaphragm, which was resected. Histologic examination of all surgical specimens revealed the presence of vital neoplastic tissue; only two specimens of carcinoid tumors showed more than 50% necrosis of the nodules treated percutaneously. These results led us to express doubts as to the efficacy of percutaneous ablative treatment for liver metastases.

Carcinoid Tumor↗
PubMed1998

Conservative surgical management of perforating Crohn's disease: side-to-side enteroenteric neoileocolic anastomosis: report of two cases.

Conservative surgical management of jejunoileal Crohn's disease is the first-choice treatment in plurioperated patients with high risk of small-bowel syndrome. Treatment is more controversial in patients with a limited disease and no previous surgery, especially in those with terminal ileitis. Even in those cases we advocate conservative surgical management because we have demonstrated regression of both symptoms and morphologic lesions. Contraindications to nonresectional surgery include the presence of abscesses and fistulas. Impending short-bowel syndrome represents a partial exception to this approach. In this article two cases of conservative surgery performed in plurioperated patients with perianastomotic perforating recurrent disease are presented. We have named this procedure "side-to-side enteroenteric neoileocolic anastomosis," which is a combination of small resections and conservative procedure. This operative strategy leads us to believe that nonresectional surgery could be selectively performed even in patients with perforating Crohn's disease.

Adult↗
PubMed1998

Lamivudine treatment for acute hepatitis B after liver transplantation.

BACKGROUND/AIMS: Acute hepatitis caused by recurrent or de novo hepatitis B virus (HBV) infection after liver transplantation frequently induces aggressive disease leading to liver failure. The aim of this study was to determine the efficacy and safety of lamivudine treatment in post-transplant acute hepatitis B. METHOD: Twelve patients with acute hepatitis B were started on lamivudine 100 mg p.o. daily within 8 weeks of the appearance of HBsAg. One patient was excluded after 1 month because of hepatocellular carcinoma recurrence. Patients were followed for an average of 68.6 weeks (range 32-108), and were clinically and biochemically evaluated on a monthly basis. They had a histological assessment at baseline, after at least 6 months, and whenever clinically indicated. RESULTS: Basal HBV-DNA ranged between 13 and 1288 pg/ml and serum alanine aminotransferase between 97 and 1036 U/l. HBV-DNA became undetectable within 8 weeks and transaminases normalized within 24 weeks in all cases. At the last visit, eight patients (73%) remained HBV-DNA negative by liquid hybridization and had normal or close to normal alanine aminotransferase. Five patients (45%) were also HBsAg negative and HBV-DNA negative by polymerase chain reaction. HBV-DNA and transaminase breakthrough occurred in three patients (27%). Histology after 6-9 months showed chronic hepatitis in seven patients. Lamivudine was well tolerated without serious adverse reactions. CONCLUSIONS: These results indicate that lamivudine treatment induces sustained inhibition of viral replication and normalization of transaminases in the majority of post-transplant patients with acute hepatitis B. HBsAg loss may be achieved in a considerable number of cases. Although viral resistance is relatively frequent, early initiation of lamivudine appears to be effective and safe.

Acute Disease↗
PubMed1998

Solitary necrotic nodules of the liver.

An experience is reported with solitary necrotic nodules of the liver, rare benign lesions described for the first time in 1983. Two patients were referred to our department because of the presence of hepatic lesions that radiology showed to be suspected secondary liver tumors. At laparotomy, both patients underwent liver resections because the lesions appeared to be malignant. Subsequent histological examination of the surgical specimens revealed that both were solitary necrotic nodules of the liver. These were the only solitary necrotic nodules found in a total of 840 operations carried out in our department since October 1981. Although they are completely benign, solitary necrotic nodules have a similar ultrasound pattern and radiological features to metastases and have been described in the literature during the follow-up of patients with other tumors. Uncertainty remains as to the etiology of these lesions, which still represent an occasional finding in liver surgery.

Aged↗
PubMed1998

Surgical treatment of hepatocellular carcinoma on cirrhosis: a Western experience.

Recent improvements on the therapeutical management of hepatocellular carcinoma (HCC) on cirrhosis have led to further evaluate the role of surgery for this disease. In a 15-year period we have evaluated 532 cirrhotics with HCC on cirrhosis. Contraindications for surgery were founded in 170 (31.9%); 37 of them received a transarterial chemoembolization and 2 a percutaneous ethanol injection. Laparotomy was performed in 315 (59.2%) cases, but in 77 surgical treatment was contraindicated due to unexpected intraoperative findings. A liver resection was performed in 238 (44.7%) patients, representing the 26.1% of all liver resections performed at our Department. Seventy-eight (32.8%) were subsegmentectomies, 143 (60.1%) segmentectomies (including 1 to 3 anatomical segments) and 17 major hepatectomies. Overall 30-day mortality was 4.6%: 9.3% during years 83-91 and 0.8% during following years (P<0.005). Five-year actuarial survival rate was 41.3%. The remaining 47 (8.8%) patients were placed on the waiting list for orthotopic liver transplantation (OLT) and 41 already operated on. Operative mortality was 6.2% and 5-year actuarial survival rate 58.1%. The persistent shortage of organ donor represents the major factor limiting the application of liver transplantation for a larger number of patients carrying HCC on cirrhosis. Liver resection remains the option to be considered for all the patients with such a disease, even if in a large proportion of cases this procedure offers only a limited survival.

Carcinoma, Hepatocellular↗
PubMed1997

Total vascular exclusion of the liver during hepatic surgery. Selective use, extensive use, or abuse?

OBJECTIVES: To review our experience with total vascular exclusion of the liver and to assess its role in hepatic resections. DESIGN: Retrospective survey. SETTING: University hospital, a tertiary referring center for surgical liver diseases. PATIENTS: A total of 722 patients who underwent liver resections from November 1, 1981, to March 31, 1996, of whom 19 (2.6%) required total vascular exclusion because of hepatic lesions closely adherent to or infiltrating the retrohepatic vena cava or centrally located in the liver, strictly in contact with the hepatic vein convergence. MAIN OUTCOME MEASURE: chi 2 Test for qualitative data and Student t test for categorical data. RESULTS: Of the 19 resections carried out under total vascular exclusion, 6 had tumoral infiltration of the retrohepatic vena cava: in 4 cases the venous wall was partially resected, while in the remaining 2 it was completely removed and replaced with a prosthetic graft. There were no operative deaths. Of the 722 resections, 227 were major hepatectomies: 74 (32.6%) were performed after ligation of the glissonian elements for the hemiliver to be removed, without clamping of the hepatic pedicle, and a further 36 (15.8%) were performed without any preliminary vascular control. A significant reduction in intraoperative blood transfusions was achieved despite the performance of more extended operations, regardless of the technique used. CONCLUSIONS: Total vascular exclusion is a useful tool in controlling blood inflow to the liver, but true need for it during liver resection is limited. Its performance requires a well-trained team familiar with problems regarding surgical access to the inferior vena cava and prolonged occlusion of the hepatic pedicle and the inferior vena cava.

Adolescent↗
PubMed1997

Duodenal involvement of Crohn's disease: three different clinicopathologic patterns.

PURPOSE: This study was designed to assess clinical and pathologic features of duodenal Crohn's disease (CD) and address its management according to different patterns of disease. METHODS: Twelve cases of duodenal involvement in CD are reported out of 336 patients treated between 1978 and 1993. They represent 3.6 percent of all cases. Three patients had a duodenal fistula, and nine had an intrinsic duodenal lesion. The duodenal fistula was in all cases a manifestation of recurrent CD involving an ileocolic anastomosis and the third portion of the duodenum. RESULTS: Treatment consisted of resection of the fistula's source and primary closure of duodenal breach. Of nine patients with intrinsic CD, five had stenosis and the remaining four had peptic ulcer-like lesions. Duodenal stenosis was treated with strictureplasty in three cases and duodenojejunostomy in two. No patient with ulcer-like lesions underwent surgery. CONCLUSIONS: Differences encountered in intrinsic duodenal lesions apparently reflect two different clinical patterns. Stenosis is not usually associated with multifocal disease and is often the first evidence of disease. Ulcer-like lesions are not specific; they do not evolve into stenosis as do ulcers in other sites of the disease, spontaneously disappear and relapse, and do not require surgery, except for complications. They are always associated with other locations of the disease.

Adult↗
PubMed1997

Conservative surgical management of terminal ileitis: side-to-side enterocolic anastomosis.

PURPOSE: Terminal ileitis is the most frequent presentation of Crohn's disease. Resection of the terminal ileum and cecum with ileocolic anastomosis has always been considered the "gold standard" in the surgical treatment of this condition. This study illustrates an alternative technique referred to as "side-to-side enterocolic anastomosis." METHODS: It consists of a longitudinal section of the terminal ileum starting 1 to 2 cm away from the beginning of the stricture and continued for a similar length on the ascending colon. A side-to-side anastomosis is then fashioned, in a kind of Finney-shaped strictureplasty. A series of five patients is reported. RESULTS: Average length of the anastomosis was 18.4 (range, 12-25) cm. Postoperative course was uneventful. Colonoscopy and large-bowel enema performed on some patients six months after surgery revealed a complete morphologic regression of the disease. All patients are presently in good condition, with no evidence of recurrence after an average follow-up of 8.9 (range, 6-15) months. CONCLUSIONS: "Side-to-side enterocolic anastomosis" can be a possible alternative option for the surgical management of Crohn's disease of the terminal ileum, providing at least regression of the morphologic aspects of the disease. Contraindications are presence of abscesses, fistulas, or rigid and fibrotic stricture. This technique can be considered a further example of nonresectional surgery such as strictureplasty. This makes it possible to conceive surgical treatment of Crohn's disease without resection in selected cases for the whole length of the small bowel and suggests the introduction of the new definition of "conservative surgical management of small-bowel Crohn's disease."

Adult↗
PubMed1997

Piggy-back versus conventional technique in liver transplantation: report of a randomized trial.

Liver transplantation with preservation of the recipient vena cava (the "piggy-back" technique) has been proposed as an alternative to the traditional method. We performed a randomized study on 39 cirrhotic patients, 20 who underwent the piggy-back technique (group 1) and 19 the traditional method using venovenous bypass (group 2) to evaluate the feasibility and true advantages of the piggy-back technique compared to the traditional method. Two patients were switched to the conventional technique due to the presence of a caudate lobe embracing the vena cava in one patient and a caval lesion in the other. Statistically significant differences between the two groups were only found for the warm ischemia time (48.5 +/- 13 min for piggy-back vs 60 +/- 12 min for the conventional method) and for renal failure (zero cases in group 1 vs four cases in group 2). We therefore believe that liver transplantation with the piggy-back technique can easily be performed in almost all cases, and that only a few, specific situations, such as a very enlarged caudate lobe, do not justify its routine use.

Adult↗
PubMed1997

De novo hepatitis B and C viral infection after liver transplantation.

Hepatitis B (HBV) and hepatitis C (HCV) viral infections often recur after orthotopic liver transplantation (OLT), but viral infections acquired with OLT have not been widely investigated. The aim of the study was to evaluate the incidence, evolution, and diagnostic problems of de novo HBV and HCV infections in liver transplant recipients with long-term follow-up. Altogether 121 transplant recipients entered the study. HBV, HDV, and HCV infections were diagnosed by means of serology and the polymerase chain reaction (PCR). Three patients became hepatitis B surface antigen (HBsAg)-positive after OLT, all of whom showed signs of persistent viral replication. Twelve patients became anti-HCV-positive after OLT: After clearance of passive antibodies, active anti-HCV seroconversion was usually delayed. The viral genome was detected in 9 of 12 patients, with fluctuations of viremia during their follow-up. The other three patients, who were HBsAg-positive before and after OLT, were repeatedly HCV-RNA-negative despite persistent anti-HCV reactivity. Four pre-OLT HBsAg-positive patients had evidence of HBV-related liver transplant disease. The remaining 8 of 12 patients experienced repeated alanine aminotransferase increases more than two times normal after transplant. De novo infections due to primary hepatotropic viruses were frequent after OLT in our experience. Early diagnosis of infection, especially when the HCV is involved, may be problematic and should be taken into account in patients showing persistent aminotransferase abnormalities. Monitoring viral markers and accurate evaluation of biopsy specimens are mandatory. The interference between HBV and HCV might play a role in the replicative cycle of one or both viruses in co-infected patients.

Antibodies, Viral↗