First Magnetic Resonance Imaging-Guided Aortic Stenting and Cava Filter Placement Using a Polyetheretherketone-Based Magnetic Resonance Imaging-Compatible Guidewire in Swine: Proof of Concept

The purpose of this study was to demonstrate feasibility of percutaneous transluminal aortic stenting and cava filter placement under magnetic resonance imaging (MRI) guidance exclusively using a polyetheretherketone (PEEK)-based MRI-compatible guidewire. Percutaneous transluminal aortic stenting and cava filter placement were performed in 3 domestic swine. Procedures were performed under MRI-guidance in an open-bore 1.5-T scanner. The applied 0.035-inch guidewire has a PEEK core reinforced by fibres, floppy tip, hydrophilic coating, and paramagnetic markings for passive visualization. Through an 11F sheath, the guidewire was advanced into the abdominal (swine 1) or thoracic aorta (swine 2), and the stents were deployed. The guidewire was advanced into the inferior vena cava (swine 3), and the cava filter was deployed. Postmortem autopsy was performed. Procedural success, guidewire visibility, pushability, and stent support were qualitatively assessed by consensus. Procedure times were documented. Guidewire guidance into the abdominal and thoracic aortas and the inferior vena cava was successful. Stent deployments were successful in the abdominal (swine 1) and thoracic (swine 2) segments of the descending aorta. Cava filter positioning and deployment was successful. Autopsy documented good stent and filter positioning. Guidewire visibility through applied markers was rated acceptable for aortic stenting and good for venous filter placement. Steerability, pushability, and device support were good. The PEEK-based guidewire allows either percutaneous MRI-guided aortic stenting in the thoracic and abdominal segments of the descending aorta and filter placement in the inferior vena cava with acceptable to good device visibility and offers good steerability, pushability, and device suppor

The impact of data quality and analytical capabilities on planning performance: insights from the automotive industry

Conventional wisdom suggests that data quality plays a central role for compiling valid and reliable plans to make the right decisions. At the same time, it is acknowledged that planning processes are both data and knowledge intensive and characterized by the human-computer interface. However, there are limited academic investigations on how data quality and analytical capabilities simultaneously impact planning performance. Drawing on the conceptual approach of business analytics, we introduce the notion of analytical capabilities, which is operationalized through three distinct resources: IT-usability, user competence, and analytical execution. To assess the impact of data quality and analytical capabilities on planning performance, we develop a structural equation model, which is then tested using data from the automotive industry. Our results suggest that analytical capabilities are a significant mediator for the effect of data quality on planning performance

KTR: An efficient key management scheme for secure data access control in wireless broadcast services recovery

Recent growth in brain-computer interface (BCI) research has increased pressure to report improved performance. However, different research groups report performance in different ways. Hence, it is essential that evaluation procedures are valid and reported in sufficient detail. In this chapter we give an overview of available performance measures such as classification accuracy, cohen’s kappa, information transfer rate (ITR), and written symbol rate. We show how to distinguish results from chance level using confidence intervals for accuracy or kappa. Furthermore, we point out common pitfalls when moving from offline to online analysis and provide a guide on how to conduct statistical tests on (BCI) results

Medical students’ education on organ donation and its evaluation during six consecutive years: results of a voluntary, anonymous educational intervention study

BACKGROUND: One of the main reasons for organ shortage is insufficient education on organ donation. Knowledgeable medical students could share the information with friends and families resulting in a positive attitude to organ donation of the general public. METHODS: During six consecutive years (2009 to 2014), we conducted a voluntary, anonymous educational intervention study on organ donation among fourth year medical students in the course of the main surgery lecture at the University of Essen, Germany. RESULTS: Questionnaires of 383 students were analyzed. Prior to the specific lecture on organ donation, 64% of the students carried a signed organ donor card with the intention to donate. Further information regarding organ donation was required by 37% of the students. The request for further information was statistically significantly higher among students without a donor card compared to organ donor card carriers (P < 0.0001). After the lecture, the number of students requiring further information decreased statistically significantly to 19% (P < 0.0001). CONCLUSIONS: Already a 45-minute lecture for fourth year medical students significantly decreases their request for further information on organ donation and improves their attitude to organ donation. Continued training on organ donation will help medical students to become disseminators for this important topic in our society

All-In-One: Advanced preparation of Human Parenchymal and Non-Parenchymal Liver Cells

BACKGROUND & AIMS: Liver cells are key players in innate immunity. Thus, studying primary isolated liver cells is necessary for determining their role in liver physiology and pathophysiology. In particular, the quantity and quality of isolated cells are crucial to their function. Our aim was to isolate a large quantity of high-quality human parenchymal and non-parenchymal cells from a single liver specimen. METHODS: Hepatocytes, Kupffer cells, liver sinusoidal endothelial cells, and stellate cells were isolated from liver tissues by collagenase perfusion in combination with low-speed centrifugation, density gradient centrifugation, and magnetic-activated cell sorting. The purity and functionality of cultured cell populations were controlled by determining their morphology, discriminative cell marker expression, and functional activity. RESULTS: Cell preparation yielded the following cell counts per gram of liver tissue: 2.0+/-0.4x107 hepatocytes, 1.8+/-0.5x106 Kupffer cells, 4.3+/-1.9x105 liver sinusoidal endothelial cells, and 3.2+/-0.5x105 stellate cells. Hepatocytes were identified by albumin (95.5+/-1.7%) and exhibited time-dependent activity of cytochrome P450 enzymes. Kupffer cells expressed CD68 (94.5+/-1.2%) and exhibited phagocytic activity, as determined with 1mum latex beads. Endothelial cells were CD146+ (97.8+/-1.1%) and exhibited efficient uptake of acetylated low-density lipoprotein. Hepatic stellate cells were identified by the expression of alpha-smooth muscle actin (97.1+/-1.5%). These cells further exhibited retinol (vitamin A)-mediated autofluorescence. CONCLUSIONS: Our isolation procedure for primary parenchymal and non-parenchymal liver cells resulted in cell populations of high purity and quality, with retained physiological functionality in vitro. Thus, this system may provide a valuable tool for determining liver function and disease

Online Intervention Study - Willingness to donate organs among the employees of a German University

BACKGROUND: Organ shortage remains a major challenge in transplantation medicine. The aim of this study was to analyze the public’s willingness to donate organs and to observe whether increased knowledge about organ donation has an effect on the attitude toward organ donation. The study in particular tested the efficacy of using electronic communication as a means to distribute information. METHODS: In 2011, an Email invitation to participate in a survey was sent to the employees of the University Duisburg-Essen. The survey consisted of a two-piece questionnaire with an informational intervention on organ donation between the questionnaires. The technical design ensured that interviewees remained anonymous and could participate only once. RESULTS: In total, 1,818 interviewees completed the questionnaire. Of the respondents, 42% were organ-donor card holders (which was consistent among genders and age groups), whereas 87% of the interviewees would support an organ donation for themselves. Of the interviewees who did not possess an organ-donor card, 67% were positively inclined toward holding one in future after reading the interventional information. CONCLUSIONS: The considerable improvement in attitude toward carrying an organ-donor card after reading the information illustrates the effectiveness of distributing concise information on organ donation. To increase the willingness to donate organs, it is of great importance to inform the public and facilitate the documentation of a decision to donate. The present study has proven the use of Email communication to be an important asset to this process

Neurologic complications in adult living donor liver transplant patients: an underestimated factor?

Liver transplantation is the only curative treatment in patients with end-stage liver disease. Neurological complications (NC) are increasingly reported to occur in patients after cadaveric liver transplantation. This retrospective cohort study aims to evaluate the incidence and causes of NC in living donor liver transplant (LDLT) patients in our transplant center. Between August 1998 and December 2005, 121 adult LDLT patients were recruited into our study. 17% of patients experienced NC, and it occurred significantly more frequently in patients with alcoholic cirrhosis (42%) and autoimmune hepatitis (43%) as compared with patients with hepatitis B or C (9/10%, P = 0.013). The most common NC was encephalopathy (47.6%) followed by seizures (9.5%). The choice of immunosuppression by calcineurin inhibitor (Tacrolimus or Cyclosporin A) showed no significant difference in the incidence of NC (19 vs. 17%). The occurrence of NC did not influence the clinical outcome, since mortality rate, median ICU stay and length of hospital stay were similar between the two groups. Most patients who survived showed a nearly complete recovery of their NC. NCs occur in approximately 1 in 6 patients after LDLT and seem to be predominantly transient in nature, without major impact on clinical outcome

Liver-First Approach for Synchronous Colorectal Metastases : Analysis of 7360 Patients from the LiverMetSurvey Registry

Background The liver-first approach in patients with synchronous colorectal liver metastases (CRLM) has gained wide consensus but its role is still to be clarified. We aimed to elucidate the outcome of the liver-first approach and to identify patients who benefit at most from this approach. Methods Patients with synchronous CRLM included in the LiverMetSurvey registry between 2000 and 2017 were considered. Three strategies were analyzed, i.e. liver-first approach, colorectal resection followed by liver resection (primary-first), and simultaneous resection, and three groups of patients were analyzed, i.e. solitary metastasis, multiple unilobar CRLM, and multiple bilobar CRLM. In each group, patients from the three strategy groups were matched by propensity score analysis. Results Overall, 7360 patients were analyzed: 4415 primary-first, 552 liver-first, and 2393 simultaneous resections. Compared with the other groups, the liver-first group had more rectal tumors (58.0% vs. 31.2%) and higher hepatic tumor burden (more than three CRLMs: 34.8% vs. 24.0%; size > 50 mm: 35.6% vs. 22.8%; p < 0.001). In patients with solitary and multiple unilobar CRLM, survival was similar regardless of treatment strategy, whereas in patients with multiple bilobar metastases, the liver-first approach was an independent positive prognostic factor, both in unmatched patients (3-year survival 65.9% vs. primary-first 60.4%: hazard ratio [HR] 1.321, p = 0.031; vs. simultaneous resections 54.4%: HR 1.624, p < 0.001) and after propensity score matching (vs. primary-first: HR 1.667, p = 0.017; vs. simultaneous resections: HR 2.278, p = 0.003). Conclusion In patients with synchronous CRLM, the surgical strategy should be decided according to the hepatic tumor burden. In the presence of multiple bilobar CRLM, the liver-first approach is associated with longer survival than the alternative approaches and should be evaluated as standard.Peer reviewe