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In this paper due to the abundant and also different applications of carbon nanotubes doped with boron, molecular vibrations related to boron element were identified and investigated in B-doped carbon nanotubes by experimental, computational and simulation ‎methods. In the experimental approach, Raman spectra of MWCNTs and B- doped MWCNTs were recorded and the Raman active modes assigned to the relevant specific vibrations. In the computational approach, the vibrational frequencies of C-C and C-B (pure carbon chains and doped with boron) oscillators were simulated using simple harmonic oscillator model and shift of vibrational frequencies toward lower wavenumbers was observed. Finally, by software simulation approach, vibrational frequencies of carbon-carbon and carbon-boron were investigated using the Gaussian software. The D- band intensity increased as the boron concentration reached to 3% while the center of the peak downshifted by 8 cm-1 (1336 cm-1 ® 1328 cm-1). Doping of carbon nanotubes with the boron concentration in the range of 4 to 10% upshifted the D- band central position by 18 cm-1 (1328 cm-1® 1346 cm-1). The ID-IG ratio (the intensity of the disorder D mode divided by the intensity of the graphite G mode) was increased by B-doping of carbon nanotubes (0.75®1.5). In conclusion, the results of the present article reveals that the intensity and frequency variations of D and G modes in the pure and the B doped MWCNT structures were approved with acceptable accuracy by the experimental, computational and simulation methods.

Background/aims: Few reports have analyzed short- and long-term outcomes in the subset of patients with hepatocellular carcinoma (HCC) on non-cirrhotic liver., Methodology: From January 1985 to December 2002, 277 patients underwent liver resection for HCC; in only 47 the liver was normal or showed mild chronic hepatitis at histology., Results: A major hepatectomy (MHR) was accomplished in 37 cases (78.7%) including an extended hepatic resection in 18 (38.3%). In-hospital mortality was nil. The rate of complications was 40.4%. Overall and disease-free survival rates at 5 years were 30.9% and 33.9%. Fifteen patients are actually alive with a median survival of 33.3 months. By multivariate analysis, tumor size > 10cm and presence of satellite nodules were independent predictive factors of 5-year survival; median survival of thirteen patients with HCCs < or = 10cm and without daughter nodules was 60 months. Twenty-six patients had a margin less than 1cm and without cancer involvement; overall and recurrence-free survival rates were comparable to those of the patients with a > 1cm margin., Conclusions: In the treatment of HCC without cirrhosis, major hepatic resections are often needed. Tumors less than 10cm in size and without satellite nodes are the best candidates for operation. The width of the resection margin is unimportant provided that there is no microscopic infiltration.

Aims: To evaluate short- and long-term results of liver resections and prognostic factors in cirrhotic patients with hepatocellular carcinoma., Study Design: A single-unit, retrospective study analyzing 216 patients with histologically confirmed cirrhosis who underwent hepatic resection for hepatocellular carcinoma. All clinico-pathologic and follow-up data were collected prospectively., Results: Child A patients had a significantly lower in-hospital mortality rate compared to Child B-C: 4.7 vs 21.3% (p=0.0003). Overall morbidity rate was 38.4%; multiple logistic regression analysis identified liver function, hepatic pedicle clamping time, number of nodes and transfusion rate as independent predictors for post-operative complications. Overall and disease-free 5-year survival rates were 34.1 and 25.2%. Multivariate analysis showed that Child A, radical resection, tumour size < or =5 cm and, absence of vascular invasion were independent prognostic factors for long-term survival. No significant differences in overall and disease-free survival were found according to the type of resection (anatomic vs non-anatomic)., Conclusions: Patients with preserved liver function and small-size, single-node hepatocellular carcinomas are the best candidates for hepatic resection.

Background and Objectives: After curative resection of hepatic colorectal metastases, 10-20% of patients experience a resectable hepatic recurrence. We wanted to assess the expected risk-to-benefit ratio in comparison to first hepatectomy and to determine the prognostic factors associated with survival., Methods: Twenty-nine patients from a group of 152 patients resected for colorectal liver metastases underwent 32 repeat hepatectomies., Results: In-hospital mortality was 3.5% (1/29 patients); the morbidity after repeat hepatectomy was lower than that after first hepatic resection. Combined extrahepatic surgery was performed on 34.5% of repeat hepatectomies vs. 6.9% of first hepatectomies (P = 0.01). Overall actuarial 3-year survival was 35.1%: four patients have survived more than 3 years and one survived for more than 5 years. The number of hepatic metastases and the carcinoembryonic antigen (CEA) serum levels were significant prognostic factors on univariate analysis. The synchronous resection of hepatic and extrahepatic disease was not associated with a lower survival rate when compared with that of patients without extrahepatic localization: three patients of the former group are alive and disease-free at more than 2 years., Conclusions: Repeat hepatic resection can provide long-term survival rates similar to those of first liver resection, with comparable mortality and morbidity. The presence of resectable extrahepatic disease must not be an absolute contraindication to synchronous hepatectomy because long-term survival is possible.

Aims: Spontaneous rupture of hepatocellular carcinoma (HCC) is a life-threatening event, particularly in patients with associated cirrhosis. We present our experience of hepatic resection of ruptured HCC., Methods: We performed 199 resections of hepatocellular carcinoma between January 1984 and December 1999. Six (3%) of these patients were operated on as an emergency because of haemoperitoneum: in five the liver was cirrhotic., Results: The mean duration of the operation was 195+/-101 min; all the patients received blood transfusions. The overall morbidity was 50%, with a mortality rate of 16.5%. Three patients were alive at 50, 80 and 116 months respectively; two had an intrahepatic recurrence treated by chemoembolization., Conclusions: Non-surgical treatment of spontaneously ruptured hepatocarcinoma should be performed only in patients with contraindication to surgery. Hepatic resection should be the treatment of choice since, according to our experience, long-term results are similar to those of elective surgery., (Copyright 2000 Harcourt Publishers Ltd.)

Extended cholecystectomy is the only chance of a cure for patients with locally advanced cancer of the gallbladder. The aim of the study was to evaluate the short- and long-term results of surgical treatment and to define the prognostic factors associated with better survival. We conducted a retrospective study in 81 patients with gallbladder cancer admitted to our surgical department from 1985 to 1999. Radical surgery was performed on 39 patients. The type of surgical treatment was based on the TNM stage of the disease: all but stage I patients underwent extended cholecystectomy (resection of segment IVa-V, N1-2 lymph-node dissection). The mortality and morbidity rates were 5.1% and 28.2%, respectively. In the patients undergoing curative resection, the 5-year survival was 31.5% (75% in T1 patients, 57.1% in T2, 25.9% in T3 and 0% in T4. Long-term survival of patients with T1-2 tumours was significantly better than that of T3 (P = 0.02) or T4 patients (P = 0.0003); 53.6% of N0 patients were still alive at 5 years as against only 14.5% of N+ patients (P = 0.06). Depth of infiltration is an important prognostic factor. The presence of lymph-node metastases should not be a contraindication to surgery since long-term survival is possible.

Background: The aim of this study was to determine, in a prospective randomized clinical trial, whether the partial portacaval shunt offers any advantage in terms of liver function and encephalopathy rate when compared with direct side-to-side direct portacaval shunt., Methods: Forty-six "good risk" patients with cirrhosis and with documented variceal hemorrhage were randomly assigned to either a partial shunt procedure (achieved by 10-mm diameter interposition portacaval H-graft) or direct small-diameter side-to-side portacaval anastomosis., Results: Operative mortality was zero in both groups. During the follow-up period, encephalopathy developed in 3 patients in the partial shunt group and 9 in the direct shunt group (P =.04). Kaplan-Meier analysis demonstrated that encephalopathy-free survival was significantly longer in the partial shunt group (P =.025). Direct shunt patients had significant hepatic functional deterioration postoperatively compared with the partial shunt group., Conclusions: The partial portacaval shunt effectively controls variceal hemorrhage. Compared with direct side-to-side portacaval shunt, partial shunt preserves long-term hepatic function and minimizes postoperative encephalopathy. We conclude that the partial portacaval shunt is the preferred approach over direct shunts for patients with cirrhosis and with variceal bleeding.

Aims: Extended operations are the only chance of a cure for patients with advanced gallbladder carcinoma, but there is no consensus about which subset of patients can benefit. The aim of this retrospective study is to evaluate the results of surgical resection with special reference to the prognostic factors and to long-term survival., Methods: A retrospective review of 70 patients with a diagnosis of gallbladder cancer treated from 1985-1998 was performed: 33 patients had a curative resection and were included in this study. For stage I disease, simple cholecystectomy was considered curative; in most of the other cases, cholecystectomy was associated with lymph node dissection and liver resection., Results: Hospital mortality and morbidity were 6% and 33%, respectively. Curative resection was associated with an actuarial 5-year survival of 27.4%. Survival of pT1-2 patients was significantly better than that of pT3 (P=0.04) or pT4 patients (P=0.002). Patients with lymph node spread had a poorer prognosis (P=0.06) but four were alive and disease-free with a median survival of 22 months., Conclusions: Depth of the tumour and lymph node metastases are important prognostic factors. Patients with pT3-4 tumours or regional lymph node spread should be considered for curative resection because long-term survival is possible., (Copyright 2000 Harcourt Publishers Ltd.)

Background: DNA flow cytometry of hepatocellular carcinoma (HCC) cells has been investigated in many studies, but, to the best of our knowledge, there are no data on DNA analysis of cirrhotic parenchyma around the HCC. In this study, cell kinetics and ploidy of parenchymal cells around HCC were performed to ascertain if this would predict the possibility of recurrence in the cirrhotic areas., Methods: The DNA content of 93 cases of HCC and of cirrhotic liver around the tumor nodules was analyzed by flow cytometry. Ploidy and proliferative index of HCC and cirrhotic liver were compared with macroscopic, histologic, and clinical features of each case and linked with the behavior of these tumors. Survival curves were assessed according to the Kaplan-Meier method. A multivariate analysis based on Cox proportional hazards regression model was performed on cases of diploid cirrhosis cells in which the S-phase fraction was evaluable., Results: The univariate analysis of survival suggested significant roles for age, number of intrahepatic nodules, Edmondson-Steiner's classification, portal invasion, vascular invasion, presence of necrosis, hepatitis B surface antigen, alpha-feto-protein, Child's score, ploidy, and S-phase fraction of HCC cells. The DNA analysis of the cirrhotic cells showed that polyploidy was dramatically reduced in patients with HCC, compared with normal hepatocytes, and aneuploid clones were present among diploid cells. High S-phase fraction of cirrhotic cells and Child-Pugh classification were the strongest independent parameters affecting the tumor behavior in this study., Conclusions: The results of this study suggest that S-phase fraction of cirrhotic liver parenchyma may be employed as a new parameter in the prognostic evaluation of HCC patients.

Background: The ideal portasystemic shunt should prevent variceal hemorrhage and preserve portal flow to reduce hepatic encephalopathy. The partial shunting proposed by Sarfeh effectively controls variceal bleeding while preserving prograde hepatic portal flow., Patients and Methods: We analyzed results of the partial portacaval shunt prospectively in 43 patients undergoing small-diameter (8-mm or 10-mm) portacaval H-graft. Patients entered into the study had Child-Pugh class A and class B cirrhosis, and all had documented previous variceal hemorrhages. We used the Sarfeh technique without performing portal collateral ligation., Results: Operative mortality was 5%. Acute graft thrombosis occurred in 3 patients, 2 of whom were successfully lysed by urokinase infusion angiographically, while later graft occlusion occurred in 1 case. Only 1 patient rebled from varices in our late follow-up (14 to 65 months). Prograde portal flow was maintained in 90% of patients undergoing repeat angiography 27 +/- 13 months postoperatively. The incidence of all encephalopathy episodes was 16%, with only 1 patient having this complication chronically., Conclusions: The small-diameter portacaval H-graft of Sarfeh is an effective operation for controlling variceal hemorrhage. It preserves hepatic portal perfusion over time in the majority of patients, reducing the risk of encephalopathy. The procedure may be particularly suited for alcoholic cirrhotic patients with less advanced liver disease.

Major hepatectomy is associated with a high operative risk in patients with cirrhosis. Between June 1983 and December 1991, 33 cirrhotic patients, 31 with good liver function, underwent major liver resection for a large hepatic primary cancer. The hospital mortality rate was 3 per cent; the only death resulted from liver failure after extended right hepatectomy. None of the patients had variceal bleeding during the postoperative period. Survival rates at 1, 2 and 3 years were 66, 43 and 37 per cent respectively. Recurrence was the most common reason for late death. These results suggest that the operative risk of major hepatectomy in cirrhotic patients with a large tumour and good liver function is comparable to that of minor liver resection. Late survival is also similar to that of patients with a small tumour. Cirrhotic patients with hepatic carcinoma and good liver function are suitable for major hepatectomy.

In this paper we review an Italian series of resected primary malignant tumors of the liver, with special reference to hepatocellular carcinoma, according to the classification criteria proposed by Japanese authors. The study emphasizes the presence of a thick peritumoral capsule as the main pathological feature that would indicate survival rate after surgery.

This study was undertaken to determine the results of resection of hepatocellular carcinoma in cirrhotic patients in Europe, using the same criteria as in the Orient for detection, surgical management, and pathology of the tumors. Seventy-two patients had a liver resection. One- and 3-yr survival rates were 68% and 51%, respectively. Survival rate was significantly higher in Child's/Pugh's class A than in class B-C patients. Patients with a thickly encapsulated tumor lived longer than those with an infiltrating tumor and had in addition a significantly lower incidence of cancer recurrence. Class A patients with a thickly encapsulated hepatocellular carcinoma had a 77% 3-year survival rate. There was no relation between the size of the tumor or the presence of symptoms and survival. These data suggest that good results can be achieved by resection of hepatocellular carcinomas in European cirrhotic patients. A thickly encapsulated tumor and an adequate liver function are the main determinants of low cancer recurrence and high survival. The clinical results in this series are similar to those reported from the Orient.

Encephalopathy is the most common complication after total portal by-pass operation. 5-15% of patients have severe and intractable encephalopathy. Many medical and surgical procedures were proposed to prevent and treat this complication but none of these were effective. Two cases of patients with severe encephalopathy after side to side portal by-pass are presented. They were treated with the procedure proposed by Bismuth; it consists of a gradual suppression of the anastomosis associated with esophagogastric devascularization. In the first case we obtained the regression of encephalopathy while the second patient died portal thrombosis (probably due to this procedure) two months after surgery. Validity and efficacy of this procedure must be evaluated with a higher number of patients. This surgical technique should lead to choose the type of portal by-pass: side to side portal by-pass operation allows according to Bismuth's procedure to reestablish an hepatopetal flow.