Endogent: Centre for Anatomy and Invasive Techniques

The invention of new endoscopical techniques for surgery and interventional radiology demand improved training at postgraduate level. The Endogent Centre for Anatomy and Invasive Techniques support these requirements by establishing hands-on practical training courses by using new procedures for cadaver embalming. Cadavers fixed by conventional procedures using formalin for conservation, are of limited use for practical surgical courses due to the profound changes of colour, strength and fragility of organs and tissues. The new Thiel embalming technique is based on the use of 4-chloro-3- methylenphenol, various salts for fixation, boric acid for disinfecting, and ethylene glycol for preservation of tissue plasticity, while the concentration of formalin is kept to the strict minimum (0.8%). This results in well preserved organs and tissues concerning colour, consistency, flexibility and plasticity. The articular joints remain freely movable and the peritoneal cavity can be inflated for laparoscopic procedures. Up to now this cadaver model was used in our institute for laparoscopic bariatric surgery, colon surgery, arthroscopy and thorax surgery. Another feature is that the lungs can be ventilated during surgical procedures. Preliminary findings seem to indicate that the corpses also serve as a suitable phantom for assessing thorax radiological equipment. Expert clinicians work as tutors and give intensive instructions before the participants start with hands-on surgery. We intend to expose also our undergraduate medical students to demonstrations of surgical approaches on Thiel embalmed corpses, in order to reveal the need for detailed anatomical knowledge in the clinic at an early stage in the medical curriculum

Adapting tumor interstitial fluid pressure for intraperitoneal chemotherapy

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Abdominal decompression for abdominal compartment syndrome in critically ill patients: a retrospective study

Background. The abdominal compartment syndrome (ACS) refers to organ dysfunction that may occur as a result of increased intra-abdominal pressure (IAP). Successful management may require abdominal decompression and temporary abdominal closure (TAC). The aim of this study was to analyze the characteristics of patients requiring abdominal decompression, to describe the methods used for TAC, and to study the outcome of these patients. Methods. A series of critically ill patients who required abdominal decompression for ACS between January 2000 and March 2007 were reviewed retrospectively. Age, gender, severity of organ dysfunction before decompression and the cause of ACS as well as the type of abdominal closure system and length of ICU-stay were recorded. Definitive abdominal closure and in-hospital mortality were the main outcome parameters. Results. Eighteen patients with primary ACS and 6 with secondary ACS required decompressive laparotomy. Patients ages ranged from 18 to 89 years (mean 50.7). The median preoperative IAP was 26mmHg, and IAP decreased to 13mmHg after decompressive laparotomy. Organ function, as quantified by the SOFA scoring system, improved significantly after the intervention. Eight patients had immediate primary fascial closure after the decompressive procedure and 16 patients required TAC. The majority of the survivors underwent planned ventral hernia repair at a later stage. The mean length of stay in the ICU was 23 (+/- 16) days. Overall, fifteen patients survived (63%). Conclusions. Decompressive laparotomy was effective in reducing IAP and was associated with an improvement in organ function. In most of the patients, the abdomen could not be closed after decompression, and fascial repair was delayed

RNA-based liquid biopsies for better clinical management of Barrett’s esophagus and esophageal adenocarcinoma

In the past decades the incidence of esophageal adenocarcinoma (EAC) has increased dramatically in most Western populations. Due to the lack of symptoms EAC is often detected in a late stage, contributing to a poor 5-year survival rate. The potential of RNA (coding and miRNA) as circulating biomarker in blood has already been shown for many cancer entities but requires further investigation for EAC. In this study we will explore several RNA types in blood, including microRNA, messenger RNA, long non-coding RNA and circular RNA as a potential liquid biomarker to facilitate early diagnosis, prognosis and monitoring of esophageal adenocarcinoma We have been collecting blood and tissue samples from patients with non-dysplastic Barrett’s esophagus (NDBE), high-grade dysplasia (HGD) and EAC. Currently, our biobank includes >5000 samples from 120 patients. A proof-of-concept study was conducted including 17 patients from three groups (EAC, HGD and NDBE). For each patient, biopsies from diseased tissue and healthy tissue as well as blood were collected and analyzed using small RNA and total RNA sequencing. Gene expression analysis was performed to identify differentially expressed genes across the three groups. The highest number of significantly differentially expressed m(i)RNAs were present in the tissues of EAC versus NDBE patients, while these differences were much lower or even absent in the plasma samples. Moreover, we have identified between 1500 and 7500 unique circular RNAs in individual EAC cancer patients’ plasma, indicating promising opportunities for a blood-based liquid biomarker for BE and EAC. Currently, we are collecting additional samples to significantly increase the power of the differential expression study as well as to verify the results of our proof-of-concept study

Clinical procedure for colon carcinoma tissue sampling directly affects the cancer marker-capacity of VEGF family members

Background: mRNA levels of members of the Vascular Endothelial Growth Factor family (VEGF-A, -B, -C, -D, Placental Growth Factor/PlGF) have been investigated as tissue-based markers of colon cancer. These studies, which used specimens obtained by surgical resection or colonoscopic biopsy, yielded contradictory results. We studied the effect of the sampling method on the marker accuracy of VEGF family members. Methods: Comparative RT-qPCR analysis was performed on healthy colon and colon carcinoma samples obtained by biopsy (n = 38) or resection (n = 39) to measure mRNA expression levels of individual VEGF family members. mRNA levels of genes encoding the eicosanoid enzymes cyclooxygenase 2 (COX2) and 5-lipoxygenase (5-LOX) and of genes encoding the hypoxia markers glucose transporter 1 (GLUT-1) and carbonic anhydrase IX (CAIX) were included as markers for cellular stress and hypoxia. Results: Expression levels of COX2, 5-LOX, GLUT-1 and CAIX revealed the occurrence in healthy colon resection samples of hypoxic cellular stress and a concurrent increment of basal expression levels of VEGF family members. This increment abolished differential expression of VEGF-B and VEGF-C in matched carcinoma resection samples and created a surgery-induced underexpression of VEGF-D. VEGF-A and PlGF showed strong overexpression in carcinoma samples regardless of the sampling method. Conclusions: Sampling-induced hypoxia in resection samples but not in biopsy samples affects the marker-reliability of VEGF family members. Therefore, biopsy samples provide a more accurate report on VEGF family mRNA levels. Furthermore, this limited expression analysis proposes VEGF-A and PlGF as reliable, sampling procedure insensitive mRNA-markers for molecular diagnosis of colon cancer