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Abstract Open and practical exchange, dissemination, and reuse of specimens and data have become a fundamental requirement for life sciences research. The quality of the data obtained and thus the findings and knowledge derived is thus significantly influenced by the quality of the samples, the experimental methods, and the data analysis. Therefore, a comprehensive and precise documentation of the pre‐analytical conditions, the analytical procedures, and the data processing are essential to be able to assess the validity of the research results. With the increasing importance of the exchange, reuse, and sharing of data and samples, procedures are required that enable cross‐organizational documentation, traceability, and non‐repudiation. At present, this information on the provenance of samples and data is mostly either sparse, incomplete, or incoherent. Since there is no uniform framework, this information is usually only provided within the organization and not interoperably. At the same time, the collection and sharing of biological and environmental specimens increasingly require definition and documentation of benefit sharing and compliance to regulatory requirements rather than consideration of pure scientific needs. In this publication, we present an ongoing standardization effort to provide trustworthy machine‐actionable documentation of the data lineage and specimens. We would like to invite experts from the biotechnology and biomedical fields to further contribute to the standard.

Biliary obstruction and multiple hepatic abscesses occurred in a patient after ligation of a segmental branch of the right hepatic duct. The patient was successfully managed by transhepatic biliary drainage and balloon dilatation of an internal fistula that developed between the ligated duct and a Roux limb of jejunum. Internal biliary fistulas may be dilated using interventional radiologic techniques to permit nonobstructed bile flow. Implications for the nonsurgical treatment of biliary strictures are discussed. [ABSTRACT FROM AUTHOR]

The non-identifiability of relevant parameters is often used as a decisive argument to reject the mathematical model and (or) experimental design. This study shows by means of an example that the argument is not compelling. The experiment to be considered has been designed to determine the first few moments of the distribution of the number of gamma rays, emitted after a nuclear fusion reaction of a particular type. This task of determining moments is so complicated that certain systematic errors cannot be completely avoided. In consequence, the moments are not identifiable with respect to the usual mathematical model and the current experiment (section 2). There is no sense in rejecting the model or the experiment on the basis of this non-identifiability. It is easy to construct a simple estimator for the first moment, with properties that are not too bad (section 2). The current estimation procedures seem to be more accurate. They can even be used to estimate some higher moments. The systematic errors cannot be avoided but are negligible in many reasonable situations (section 3 and 4). The actual analysis of the data is more complicated than suggested in the first four sections. Nevertheless these sections are relevant because the underlying model gives an adequate description of the observations after a preliminary reduction of the data. This fact is intuitively clear but can also be proved (section 5). A test-case suggests that even the standard errors provided by the current technology are reliable (section 6). [ABSTRACT FROM AUTHOR]

Two liver transplant patients with hepatopetal collaterals after portal vein thrombosis are described. Angiographically, the appearance is similar to cavernous transformation of the portal vein. The demonstration of hepatopetal collaterals is diagnostic of portal vein occlusion from whatever cause. After portal vein occlusion, collaterals develop from preexisting periportal vessels which undergo compensatory enlargement and reconstitute the intrahepatic portal vessels. In liver transplant patients, the collateral communications must arise de novo, since all potential collateral pathways are severed at the time of transplantation. [ABSTRACT FROM AUTHOR]

Malignant fibrous histiocytomas are uncommon retroperitoneal soft tissue tumors. We report a case of a malignant fibrous histiocytoma of the retroperitoneum that was anmgiographically hypervascular and indistinguishable from renal cell carcinoma. Computerized tomography of the abdomen demonstrated extensive psoas muscle infiltration by tumor. This feature may be useful in differentiating a renal cell carcinoma from a primary retroperitoneal sarcoma. [ABSTRACT FROM AUTHOR]

Background: Although the presence of a contrast blush (CB) on computed tomographic (CT) scan is associated with an increased failure rate of nonoperative management in adults with blunt splenic injury, little information is available for the pediatric population, where nonoperative management is the standard of care. Our aim was to determine whether the finding of CB on CT scan could predict failure of nonoperative therapy in children with blunt splenic injury., Methods: A retrospective analysis of 343 patients admitted with blunt splenic injury to our Level I pediatric trauma center over a 7-year period was performed. All CT scans were reviewed by a radiologist who was blinded to the patient outcome. We excluded 127 patients who either underwent immediate laparotomy without a CT scan or whose CT scans were unavailable at the time of this review. We divided the patients into two groups on the basis of the presence or absence of CB on the updated reading of the CT scan. Demographic variables analyzed included age, sex, mechanism of injury, Injury Severity Score, Glasgow Coma Scale score, initial hemoglobin and hematocrit, and emergency department pulse rate and systolic blood pressure. Outcome measures compared include length of stay, length of intensive care unit stay, the need for splenic intervention, and mortality. Continuous variables were compared using Student's t test for normally distributed data and the Mann-Whitney test for skewed data. Categorical data were compared using chi2 analysis or Fisher's exact test. Statistical significance was assigned to values of p < 0.05., Results: Among the study population (N = 216), 27 patients (12.5%) had CB on CT scan. Patients with CB had significantly lower hematocrit (p = 0.0004) and required operative intervention more frequently than those without CB (22% vs. 4%;p = 0.0008). Among patients with CB, mean pulse rate at presentation was higher in those that required splenic intervention (SI) (129 +/- 20.1) compared with those who underwent successful nonoperative therapy (100.4 +/- 23.1; p = 0.01). Only grade V injuries correlated with the need for laparotomy., Conclusion: Children with blunt splenic injury who have CB on CT scan are more likely to require SI than those without CB. However, because the majority of patients with CB did not require SI, in the absence of hemodynamic instability, this finding may be insufficient to determine the need for SI. CB is a specific marker of active bleeding that may predict the need for early splenic intervention in a specific subset of patients at presentation.

Patients with advanced-stage unresectable hepatocellular carcinoma (HCC) were treated with intrahepatic arterial doxorubicin 30 mg/m2 plus escalating doses of cisplatin up to 100 mg/m2 in conjunction with rapid bolus injection of Spherex (degradable starch microspheres; Kabi Pharmacia, Lund, Sweden) into the hepatic artery, until slowing or reversal of blood flow. Treatments were repeated every 4 to 6 weeks until progression, or were continued indefinitely if there was disease stability or response. Thirty-five evaluable patients have so far been accrued to the study. Objective tumor responses have occurred in 22 patients (63%), of whom 20 had partial responses and two had complete responses. Four of the patients had reversal of tumor-induced portal vein thrombus. Toxicities included death, one patient (and a death of uncertain cause in an additional patient); hepatitis, two patients; pancreatitis, one patient; dyspnea/hypotension, two patients; and hepatic artery nontransient thrombosis in four patients. Six patients have survived 2 years and an additional 10 patients have survived 1 year. The addition of Spherex to intrahepatic arterial chemotherapy for advanced-stage HCC appears to be relatively safe and is well tolerated even in patients with portal vein thrombosis, which represent the majority of patients with advanced-stage HCC.

Purpose: To assess whether percutaneous transluminal angioplasty (PTA) can help prolong allograft survival and improve allograft function in patients with hepatic artery stenosis after liver transplantation., Patients and Methods: Hepatic artery PTA was attempted in 19 patients with 21 allografts over 12 years. The postangioplasty clinical course was retrospectively analyzed. Liver enzyme levels were measured before and after PTA to determine if changes in liver function occurred after successful PTA., Results: Technical success was achieved in 17 allografts (81%). Retransplantation was required for four of 17 allografts (24%) in which PTA was successful and four of four allografts in which PTA was unsuccessful; this difference was significant (P = .03). Two major procedure-related complications occurred: an arterial leak that required surgical repair and an extensive dissection that necessitated retransplantation 14 months after PTA. Hepatic failure necessitated repeat transplantation in seven cases from 2 weeks to 27 months (mean, 8.4 months) after PTA. Six patients died during follow-up, three of whom had undergone repeat transplantation. Markedly elevated liver enzyme levels at presentation were associated with an increased risk of retransplantation or death regardless of the outcome of PTA., Conclusion: PTA of hepatic artery stenosis after liver transplantation is relatively safe and may help decrease allograft loss due to thrombosis. Marked allograft dysfunction at presentation is a poor prognostic sign; thus, timely intervention is important.

Background: Hepatic arterial infusion of 5-fluoro-2-deoxyuridine (FUdR) is associated with a 60% response rate among previously untreated patients who have hepatic-metastatic colorectal cancer. One obstacle to further dose escalation has been concomitant hepatic toxicity. We are evaluating a FUdR-containing chemotherapeutic emulsion to further dose intensify therapy without associated toxicity., Methods: The in vitro pharmacokinetics of the emulsion were determined using high-pressure liquid chromatography (HPLC). The rate at which FUdR is released from emulsion into an overlying aqueous phase was determined in static and dynamic assays. Fifteen patients with hepatic-metastatic colorectal cancer were treated with intrahepatic arterial infusions of emulsion on a phase I dose-escalating clinical protocol. Serum collection determined systemic drug levels using HPLC., Results: In vitro studies demonstrate that FUdR is slowly released from emulsion into overlying aqueous medium. The emulsion serves as a depot for FUdR. Therapy was well tolerated. Emulsion was sequestered in the liver after infusion in all treated patients., Conclusions: This Ethiodol-based, oil-in-water emulsion serves as a sustained-release preparation of FUdR. An Ethiodol-based oil-in-water emulsion is a clinically effective vehicle for delivering FUdR to hepatic-metastatic colorectal tumors.

Purpose: The authors report their initial and long-term results using transhepatic balloon dilation to treat biliary strictures in liver transplant patients., Patients and Methods: Over a 10-year period, 72 liver transplant patients with biliary strictures underwent 81 balloon dilation treatments. Anastomotic strictures were present in 56 patients; nonanastomotic strictures were present in 16., Results: Initial technical success was achieved in 64 of 72 patients (89%). Balloon dilation failed in eight patients (11%), and they were treated surgically. Complications occurred in nine (12%) patients, and all were successfully treated. Within the first 6 months, five patients (6.9%) required surgical revision. Three patients (4.2%) underwent repeated liver transplantation; and five patients (6.9%) died. Fifty-one patients in whom balloon dilation was initially successful were available for at least a 6-month follow-up. Life-table analysis showed an overall 81% +/- 4.8 success rate at 6 months; it dropped to 70% +/- 6.2 at 6 years. For anastomotic strictures, it was 77% +/- 5.8 at 6 months and 66% +/- 7.3 at 6 years. For nonanastomotic strictures, it was 94% +/- 6.2 at 6 months, which dropped to 84% +/- 10 at 5 years., Conclusion: Transhepatic balloon dilation represents an effective and relatively safe treatment for biliary stricture in liver transplant recipients.

Rationale and Objectives: Nonionic contrast media have been shown to be more effective, better tolerated, and safer than standard high-osmolality contrast media when given intravascularly. The aim of this study was to assess the diagnostic efficacy, tolerance, and safety of a new nonionic contrast agent, iopromide (370 mg I/mL), in comparison with two available similar agents, iopamidol (370 mg I/mL) and iohexol (350 mg I/mL), in two randomized, double-blind clinical studies of patients undergoing abdominal aortography and visceral angiography., Methods: The iopromide group included 80 patients, and the comparator group consisted of 36 iopamidol and 45 iohexol patients. The quality and diagnostic efficacy of all three contrast agents was rated equally as either good or excellent., Results: On a scale of 0 (none) to 3 (severe) for heat and pain, respectively, the mean scores were 1.08 and 0.43 for iopromide in comparison with 1.15 and 0.35 for the comparator media. Minor adverse clinical experiences were noted in 23% of the iopromide group versus 20% of the comparator group. Nausea and vomiting were more common in the comparator group (7% versus 3%), and headache was noted only in the iopromide group (4%). There were no clinically significant changes in laboratory values in any group. Three severe adverse experiences occurred, but all were deemed unrelated to the contrast agents., Conclusion: Based on the results of this study, iopromide appears to be efficacious, safe, well tolerated, and comparable with iohexol and iopamidol for use in abdominal aortography and visceral angiography.

In summary, interventional techniques are well-established and offer safe and effective alternatives for management of patients in the intensive care unit or other setting. It is likely that the radiologist will become more involved in the management of ill children and adults. It is hoped that this will reduce the need for opened surgical procedures, reduce the complexity of surgery, and provide treatment options for complications.

Purpose: The authors evaluated the safety and efficacy of percutaneous transluminal angioplasty (PTA) for the treatment of venous stenoses in liver transplant recipients., Patients and Methods: Over a 5-year period, 15 venous stenoses were treated with PTA in 12 patients with liver transplants (seven children and five adults). PTA was performed for portal vein stenoses in five patients, inferior vena cava (IVC) stenoses (n = 6) in five patients, combined superior mesenteric vein-portal vein graft anastomosis and hepatic vein-IVC anastomosis in one patient, and combined IVC and hepatic vein-IVC anastomosis in one patient. PTA was repeated in three patients (five procedures) for recurrent IVC stenoses., Results: Initial technical and clinical success of PTA was achieved in 11 patients (92%); failure occurred in one patient (8%) with a portal vein anastomotic stenosis. No complications occurred in the immediate post-procedure period (up to 7 days). Nine patients (75%) are clinically well, with follow-up ranging from 7 to 33 months (mean, 18 months). Two of them required one or more repeated PTA procedures to maintain vessel patency. One patient required retransplantation for chronic rejection at 3 months, and another died of gastrointestinal tract bleeding from a gastric ulcer at 2 months after initially successful IVC PTA., Conclusions: PTA is a safe procedure for the treatment of venous anastomotic stenoses in liver transplant recipients. PTA of portal vein anastomotic stenosis has favorable intermediate-term results. Repeat PTA may be necessary in some cases of IVC anastomotic stenoses to maintain vessel patency and avoid surgical revision or retransplantation.

Malignant strictures of the extrahepatic bile ducts are difficult to distinguish from benign strictures, particularly in patients with primary sclerosing cholangitis. Because attempts at diagnosing small cancers with fine-needle aspiration biopsy are not possible in the absence of an associated mass lesion and because the sensitivity of exfoliative biliary cytology is controversial, brush cytology has been used as a potential means of establishing a specific diagnosis of bile duct carcinoma. Herein we report our experience with this technique when performed on 65 patients over a 5-yr period. Each had at least one brushing. Thirty-seven were found to have bile duct carcinoma and 28 were found to have benign strictures. Of these 37, the first brushing was positive for malignancy in 15 (40%), whereas four (11%) had cells suspected but not diagnostic of malignancy. Thirteen patients with bile duct carcinoma whose initial brushings were negative for malignancy had second brushings. Of these, five (38%) had malignant cells, whereas three (24%) yielded suspicious cells. Three of the eight whose first two brushings were negative for malignancy were found to have malignant cells on the third brushing. In contrast, of the 28 patients with benign strictures, malignant cells were never found. However, in two patients, suspicious cells were reported with the first but not the second brushing. A single negative or suspicious cytological finding decreased the probability of bile duct carcinoma to 43%. Two and three sequential negative tests reduced the probability to 32% and 0%, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)