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41.

Background

Bile duct strictures remain a major source of morbidity after orthotopic liver transplantation (OLT). Endoscopic management by the conventional methods of biliary dilatation and/or stent placement has been successful, but sometimes severe complications occur, necessitating prolonged therapy. The aim of this study is to clarify the complications of the endoscopic approach for endoscopic dilatation and/or stent placement.

Method

Of 46 patients who underwent living-donor liver transplantation, 10 were diagnosed as having anatomic biliary strictures by endoscopic retrograde cholangiopancreatography (ERCP). Two patients developing biliary strictures after deceased-donor liver transplantation were also enrolled in the study. For the purpose of comparison, 302 patients with a total of 550 consecutive ERCP cases (including 115 patients with 250 malignant bile duct strictures) were recruited in this study. Success rate, number of endoscopy sessions, the median procedure time for ERCP, and incidence of complications including post-ERCP pancreatitis were compared in the OLT cases and other cases.

Results

The following results were obtained in the OLT cases, malignant stricture cases, and all cases, respectively: mean number of endoscopy sessions was 3.62, 2.17, and 1.94 (P?=?0.0216, P?P?=?0.0327, P?=?0.0093); and severe pancreatitis occurred in 2 cases of OLT. In a univariate analysis for post-ERCP pancreatitis, OLT was extracted as the only significant risk factor.

Conclusions

Endoscopic maneuvering for biliary dilatation and/or stent placement following OLT was associated with a higher risk of post-ERCP pancreatitis than the use of the same technique for the treatment of malignant biliary stricture. Endoscopic treatment after OLT was a significant risk factor for post-ERCP pancreatitis.  相似文献   
42.
Effects of conditioned emotional stimuli (CES), which induce psychological stress, on the expression of cerebral diazepam binding inhibitor (DBI) mRNA in mouse were examined using a communication box. Cerebral DBI mRNA expression significantly increased in a time-dependent manner after the application of CES. The maximal enhancement of DBI mRNA expression was observed 2 days after the application of CES, and this increase faded out over 7 days after the treatment. Flunitrazepam (1 mg/kg), an agonist for central benzodiazepine (BZD) receptors, completely abolished the CES-induced elevation of cerebral DBI contents and its mRNA expressions. These results indicate that cerebral DBI is enhanced by psychological stress, which is regulated by central BZD receptors.  相似文献   
43.
The antithrombotic efficacy of FK419, a novel nonpeptide platelet glycoprotein IIb/IIIa antagonist, was compared with tirofiban in guinea-pigs. FK419 and tirofiban similarly inhibited platelet aggregation in vitro (IC50 values: 0.43+/-0.076 and 0.41+/-0.053 micromol/L) and dispersed aggregated platelets (EC50 values: 2.3+/-0.88 and 2.0+/-0.81 micromol/L). FK419 inhibited retention of platelets and neutrophils in a collagen-coated bead column with greater potency than tirofiban (IC50 values of 0.90+/-0.133 and 2.4+/-0.21 micromol/L for platelet retention and 0.32+/-0.078 and 0.57+/-0.180 micromol/L for neutrophil retention). When FK419 or tirofiban were administered after photochemically induced middle cerebral artery (MCA) occlusion in guinea-pigs, they dose-dependently improved MCA patency. FK419 reduced neurological deficits and ischemic brain damage in a dose-dependent fashion, whereas tirofiban did not. Reduced regional cerebral blood flow in the striatum gradually returned to the preoccluded level with FK419 treatment; however, no restoration was observed with tirofiban even though the MCA was recanalized. These results indicate that FK419 ameliorates ischemic brain damage by not only lysing the obstructive thrombus in MCA but also preventing or restoring microcirculation deficits after occlusion/reperfusion, suggesting that FK419 would be an attractive intervention for the treatment of ischemic stroke patients.  相似文献   
44.
To evaluate how the intraventricular blood flow is affected by the size of a left ventricular aneurysm and ventricular dysfunction, systolic left ventricular blood flow patterns were evaluated using two-dimensional Doppler flow images (real-time 2-D Doppler echo). The subjects consisted of 10 normal controls, 35 patients with anteroseptal infarction, two patients with inferior infarction and five patients with anteroseptal-inferior infarctions. The systolic period was divided into three subsets; early, mid- and end-systole. Forty-two patients with myocardial infarction were classified into three groups according to the left ventricular inflow patterns on real-time 2-D Doppler echo using the apical left ventricular long-axis approach; i.e., inflow signals confined to early systole (Group I), visualized up to mid-systole (Group II) and end-systole (Group III). Left ventricular end-diastolic dimension (LVDd), left ventricular end-systolic dimension (LVDs), and % non-contractile circumference (delta L) were calculated by the same echocardiographic approach. Ejection fraction (EF) was calculated by left ventricular cineangiography using the Simpson's method. The left ventricular inflow Doppler signals in the normal controls and Group I turned in the apex and then directed toward the left ventricular outflow tract during late diastole and early systole. Significant differences in EF were observed among the three groups. EF in Group I, II and III was 53 +/- 9%, 41 +/- 8% and 29 +/- 7%, respectively. However, LVDd, LVDs and delta L had the largest values in Group III and the smallest values in Group I. LVDd, LVDs and delta L were smallest in Group I and largest in Group III. In the normal controls, the left ventricular inflow signals proceeded to the apex and directed toward the left ventricular outflow tract in the early systolic period. Various changes in the inflow pattern were observed in patients with myocardial infarction and severe wall motion abnormalities, including delayed timing in proceeding from the apex to the left ventricular outflow tract, stagnant blood at the apex and further inflow of blood toward the apex even during end-systole. The patients with sustained inflow during late systole had hypofunction of the left ventricle as demonstrated by smaller EF and larger LVDd, LVDs, and delta L. In conclusion, the observation of intracardiac blood flows by real-time 2-D Doppler echo is of help in evaluating the severity of myocardial infarction.  相似文献   
45.
46.
Size-specific dose estimate (SSDE) takes into account the patient size but remains to be fully validated for adult coronary computed tomography angiography (CCTA). We investigated the appropriateness of SSDE for accurate estimation of patient dose by comparing the SSDE and the volume CT dose index (CTDIvol) in adult CCTA. This prospective study received institutional review board approval, and informed consent was obtained from each patient. We enrolled 37 adults who underwent CCTA with a 320-row CT. High-sensitivity metal oxide semiconductor field effect transistor dosimeters were placed on the anterior chest. CTDIvol reported by the scanner based on a 32-cm phantom was recorded. We measured chest diameter to convert CTDIvol to SSDE. Using linear regression, we then correlated SSDE with the mean measured skin dose. We also performed linear regression analyses between the skin dose/CTDIvol and the body mass index (BMI), and the skin dose/SSDE and BMI. There was a strong linear correlation (r = 0.93, P < 0.001) between SSDE (mean 37 ± 22 mGy) and mean skin dose (mean 17.7 ± 10 mGy). There was a moderate negative correlation between the skin dose/CTDIvol and BMI (r = 0.45, P < 0.01). The skin dose/SSDE was not affected by BMI (r = 0.06, P > 0.76). SSDE yields a more accurate estimation of the radiation dose without estimation errors attributable to the body size of adult patients undergoing CCTA.  相似文献   
47.
48.
BACKGROUND/AIMS: The overall outcome of T2 gallbladder carcinoma has not been favorable, although there is a modest hope for long-term survival after radical resection. The aim of this study was to examine factors influencing postoperative disease-free survival of patients with T2 gallbladder carcinoma to clarify optimal treatment. METHODOLOGY: Of 53 patients with gallbladder carcinoma who had undergone surgical resection from 1985 to 2000, 22 had T2 carcinoma histologically proved. The significance of variables for disease-free survival was examined retrospectively by the Kaplan-Meier method and the log-rank test. RESULTS: There were 16 patients with stage II (T2N0M0), 6 with stage III (T2N1M0) disease. Eleven patients were treated by extended cholecystectomy with resection of the extrahepatic bile duct, 10 patients underwent extended cholecystectomy without resection of the extrahepatic bile duct, and 1 patient underwent cholecystectomy. All patients underwent lymph node dissection in the hepatoduodenal ligament, below the pancreatic head, and along the common hepatic artery. Lymph node metastasis was present in 6 patients. Lymphatic, venous, and perineural invasions were found in 9, 4, and 4 patients, respectively. The absence of lymphatic invasion was a significant factor related to good postoperative disease-free survival (5-year disease-free survival rate, 88.9% vs. 31.3% in the presence of lymphatic invasion). Lymph node, venous, or perineural invasion, and surgical procedure were not significant factors to good postoperative disease-free survival. CONCLUSIONS: For patients with T2 gallbladder carcinoma, the presence of lymphatic invasion is an unfavorable prognostic indicator that calls for additional treatment after radical surgery.  相似文献   
49.
50.

Background

Ampullary early stage cancer (early CA) potentially harbors lymphovascular invasion; there are few data on markers that could differentiate adenoma and early CA.

Aim

To investigate those markers, we compared the tumor diameter and Ki-67 expression in endoscopy biopsy specimens of adenoma with those of early CA.

Methods

Patients on whom endoscopic papillectomy (EP) was performed (n = 35) with histopathologically proven adenomas and with low/high grade dysplasia and early CA were studied. We made pre-procedure evaluations of ampullary tumors by using endoscopic ultrasonography (EUS) and transpapillary intraductal ultrasonography. Tumor diameter was measured by EUS. Endoscopic biopsy using immunostaining of Ki-67 labeling index (LI) prior to EP were evaluated.

Results

The areas under the receiver-operating characteristic (AUROC) curves for tumor diameter and Ki-67 expression were 0.824 and 0.873, respectively. Cut-off values calculated based on AUROC data were 15 mm in tumor diameter and 32 cells/high-power field (HPF) in Ki-67. Early CA (n = 11) was diagnosed by using a cut-off value for tumor diameter in 8 out of 11 patients (sensitivity 72.7 %, specificity 66.7 %, accuracy 68.6 %). Significant infiltration of the major duodenal papilla by Ki-67 positive tumor cells (>31/HPF) was recognized in 8 of the 11 patients with early CA (sensitivity 100 %, specificity 54.2 %, accuracy 62.9 %).

Conclusions

Observation of tumor diameter and Ki-67 LI would be helpful for safety EP. EP should not be indicated for ampullary tumors more than 15 mm in diameter and/or Ki-67 LI 31/HPF.  相似文献   
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