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Abstract We compared the outcomes of robotic-assisted partial nephrectomy (RPN) and open partial nephrectomy (OPN) using contemporary data to respond to unmet clinical needs. Data from patients included in the registry who underwent partial nephrectomy between January 01, 2014 and June 30, 2017 within 20 centres of the French Network for Research on Kidney Cancer UroCCR were collected (NCT03293563). Statistical methods included adjusted multivariable analyses. Rates of peri- and post-operative transfusion, and of surgical revision, were lower in the RPN (n = 1434) than the OPN (n = 571) group (2.9% vs. 6.0%, p = 0.0012; 3.8% vs. 11.5%, p

Abstract In this study, thermal energy management systems with the choices of three different thermal insulating materials are experimentally investigated for robotic applications. These insulating materials are stone wool, fiberglass and extruded polyurethane with air cooling and heating system which are evaluated in the low and high temperature environments to really assess the thermal behavior and performance in such extreme ambient conditions. In this regard, thermodynamic and heat transfer modeling studies are undertaken to investigate various performance parameters, including energy and exergy efficiencies. The experimental results showed that energy efficiencies of the thermal management methods are obtained 46.34% for stone wool, 31.15% for fiberglass, and 44.3% for air cooling system at 40°C. Moreover, the exergy efficiencies are 12.6% for stone wool, 15.08% for fiberglass, 18.91% for extruded polyurethane, and 3.86% for air cooling system.

Abstract Background The ideal extent of lymphadenectomy (LAD) in esophageal oncological surgery is debated. There is no evidence for improved survival after standardized paratracheal lymph node resection performing oncological esophagectomy. Lymph nodes from the lower paratracheal station are not standardly resected during 2-field Ivor-Lewis esophagectomy for esophageal cancer. The objective of this study was to evaluate the impact of lower paratracheal lymph node (LPL) resection on perioperative outcome during esophagectomy for cancer and analyze its relevance. Methods Retrospectively, we identified 200 consecutive patients operated in our center for esophageal cancer from January 2017 – December 2019. Patients with and without lower paratracheal LAD were compared regarding demographic data, tumor characteristics, operative details, postoperative complications, tumor recurrence and overall survival. Results 103 out of 200 patients received lower paratracheal lymph node resection. On average, five lymph nodes were resected in the paratracheal region and cancer infiltration was found in two patients. Those two patients suffered from neuroendocrine carcinoma and melanoma respectively. Cases with lower paratracheal lymph node yield had significantly less overall complicated procedures (p = 0.026). Regarding overall survival and recurrence rate no significant difference could be detected between both groups (p = 0.168 and 0.371 respectively). Conclusion The resection of lower paratracheal lymph nodes during esophagectomy remains debatable for distal squamous cell carcinoma or adenocarcinoma of the esophagus. Tumor infiltration was only found in rare cancer entities. Since resection can be performed safely, we recommend LPL resection on demand.

Abstract Background For patients with esophageal adenocarcinoma or cancer of the gastroesophageal junction, radical esophagectomy with 2-field lymphadenectomy is the cornerstone of the multimodality treatment with curative intent. Both conventional minimally invasive esophagectomy (MIE) and robot assisted minimally invasive esophagectomy (RAMIE) were shown to be superior compared to open transthoracic esophagectomy considering postoperative complications. However, no randomized comparison exists between MIE and RAMIE in the Western World for patients with esophageal adenocarcinoma. Methods This is an investigator-initiated and investigator-driven multicenter randomized controlled parallel-group superiority trial. All adult patients (age ≥ 18 and ≤ 90 years) with histologically proven, surgically resectable (cT1-4a, N0–3, M0) esophageal adenocarcinoma of the intrathoracic esophagus or adenocarcinoma of the gastroesophageal junction and with European Clinical Oncology Group performance status 0, 1 or 2 will be assessed for eligibility and included after obtaining informed consent. Patients (n = 218) with resectable esophageal adenocarcinoma of the intrathoracic esophagus or adenocarcinoma of the gastroesophageal junction are randomized to either RAMIE (n = 109) or MIE (n = 109). The primary outcome of this study is the total number of resected abdominal and mediastinal lymph nodes specified per lymph node station. Conclusion This is the first randomized controlled trial designed to compare RAMIE to MIE as surgical treatment for resectable esophageal adenocarcinoma or adenocarcinoma of the gastroesophageal junction in the Western World. The hypothesis of the proposed study is that RAMIE will result in a higher abdominal and mediastinal lymph node yield specified per station compared to conventional MIE. Short-term results and the primary endpoint (total number of resected abdominal and mediastinal lymph nodes per lymph node station) will be analyzed and published after discharge of the last randomized patient within this trial. Trial registration ClinicalTrials.gov Identifier: NCT04306458 . Registered 13th March 2020, https://clinicaltrials.gov/ct2/show/NCT04306458; Date of first enrolment 18.01.2021; Target sample size 218; Recruitment status: Recruiting; Protocol version 2; Issue date 10.03.2020; Rev. 02.02.2021; Authors ET, PCvdS, PPG.

Background: Bipolar sealing devices are routinely used to seal blood vessels. The aim of the study is to evaluate the feasibility and safety of colonic sealing with the use of the bipolar energy devices in rats as model for experimental appendectomy. Methods: Seventy-five male Wistar rats underwent a cecal resection with four different bipolar sealing devices or a linear stapler. The harvesting procedure was performed immediately or at postoperative day (POD) 7. The sealing front bursting pressure (BP) was measured in both groups. At POD7, the resection line was clinically examined and the hydroxyproline (HDP) levels were determined. Hematoxylin and Eosin (H&E) staining was used for histopathological evaluation of the sealing front as well. Results: There was no mortality and no insufficiency. The BPs between the bipolar sealing devices showed no statistical differences. The early phase of the seal (POD 0) provides a low BP with an 30.8% increase until POD 7. The BPs in the stapler group showed significant better values. The hydroxyproline levels did not differ statistically between the groups. Histopathologically, there were more signs of ischemic necrosis in the stapler group than in the sealing devices groups. Conclusion: The resection and sealing of the cecum as an experimental appendectomy model with the use of bipolar energy devices proved feasible and safe in rats. The different energy devices in this study produce comparable results. To justify clinical practice in humans, several studies on the underlying mechanisms of early stage wound healing are needed.

The main objective of the French GETUG/AFU V05 VESPER randomized phase III study was to assess the efficacy of dd-MVAC and GC in term of progression-free survival in patients for whom chemotherapy has been decided, before or after surgery.A total of 500 patients have been randomized in 28 reference centers. Inclusion criteria were urothelial carcinoma without neuro-endocrine variant, disease defined by a T2, T3 or T4a N0 (pelvic lymph node ≤ 10 mm on CT scan) M0 staging for patients receiving neoadjuvant chemotherapy or pT3 or pT4 or pN+ and M0 for patients receiving adjuvant chemotherapy. Secondary endpoints include overall survival, safety, response rate. The peri-operative chemotherapy schedule was experimental arm dd-MVAC for a total of 6 cycles versus standard arm GC 4 cycles. The toxicity was evaluated according to NCI CTCAE (v 4.0). The progression-free survival rate will be estimated at 3 years by the Kaplan-Meier method. All the patients will be followed for 5 years.The last patient was randomized in March 2018 and the primary endpoint results are expected for mid-2021. As the dd-MVAC schedule is associated with higher response rates in metastatic disease, the real question today is to confirm such benefit in the peri-operative setting, taking also in consideration the chemotherapy toxicity. Tomorrow, the challenge may be the best chemotherapy and immunotherapy association, the authors hope that final Vesper Trial results will help to determine the gold standard chemotherapy. Keywords: Bladder cancer, Peri-operative chemotherapy

Abstract The analysis of blood plasma or serum as a non-invasive alternative to tissue biopsies is a much-pursued goal in cancer research. Various methods and approaches have been presented to determine a patient’s tumour status, chances of survival, and response to therapy from serum or plasma samples. We established PNB-qPCR (Pooled, Nested, WT-Blocking qPCR), a highly specific nested qPCR with various modifications to detect and quantify minute amounts of circulating tumour DNA (ctDNA) from very limited blood plasma samples. PNB-qPCR is a nested qPCR technique combining ARMS primers, blocking primers, LNA probes, and pooling of multiple first round products for sensitive quantification of the seven most frequent point mutations in KRAS exon 2. Using this approach, we were able to characterize ctDNA and total cell-free DNA (cfDNA) kinetics by selective amplification of KRAS mutated DNA fragments in the blood plasma over the course of tumour resection and the surrounding days. Whereas total cfDNA concentrations increased over the surgical and regenerative process, ctDNA levels showed a different scheme, rising only directly after tumour resection and about three days after the surgery. For the first time, we present insights into the impact of surgery on the release of ctDNA and total cfDNA.

In this paper we introduce a parameter for the retrieval of the thickness of undeformed first-year sea ice that is specifically adapted to compact polarimetric (CP) synthetic aperture radar (SAR) images. The parameter is denoted as the "CP ratio". In model simulations we investigated the sensitivity of the CP ratio to the dielectric constant, ice thickness, ice surface roughness, and radar incidence angle. From the results of the simulations we deduced optimal sea ice conditions and radar incidence angles for the ice thickness retrieval. C-band SAR data acquired over the Labrador Sea in circular transmit and linear receive (CTLR) mode were generated from RADARSAT-2 quad-polarization images. In comparison with results from helicopter-borne measurements, we tested different empirical equations for the retrieval of ice thickness. An exponential fit between the CP ratio and ice thickness provides the most reliable results. Based on a validation using other compact polarimetric SAR images from the same region, we found a root mean square (rms) error of 8 cm and a maximum correlation coefficient of 0.94 for the retrieval procedure when applying it to level ice between 0.1 and 0.8 m thick.

Objective: The goal of this prospective study was to compare the efficiency of two types of MRU after diuretic administration to identify the non-dilated ureter. Methods: MR pelvic examinations were performed in 126 patients after receiving furosemide. Each patient underwent in addition to their protocol for context, two types of MRU: 2D T2-weighted FSE (T2w-MRU) and 3D Gd T1-weighted GE (CE-MRU). Four segments were checked for each ureter. For the first part of the analysis, readers evaluated the whole image quality using a four points subjective scale and for the second part, they were asked to score separately each ureteral segment as present or absent. Results: 1008 ureteral segments were checked. For the image quality, readers did not find any significant difference (3.8 ± 0.5 vs 3.6 ± 0.7, p value: 0.13) between MRU methods. The interobserver agreement was excellent with a κ correlation coefficient as high as 0.89 for T2w-MRU and 0.92 for CE-MRU, respectively. For the detection of the segments and considering the 9 rotations for the T2W MRU, there were no statistically significant differences between the two groups. Conclusion: T2-weighted MRU with multiple orientations and diuretic is sufficient to identify the non-dilated ureter. It offers information on ureteral peristaltism. It can be suggested that this sequence is able to detect an initial obstruction before hydronephrosis occurs.

We present the derivation of a simple viscous damping model of Kelvin–Voigt type for geometrically exact Cosserat rods from three-dimensional continuum theory. Assuming moderate curvature of the rod in its reference configuration, strains remaining small in its deformed configurations, strain rates that vary slowly compared to internal relaxation processes, and a homogeneous and isotropic material, we obtain explicit formulas for the damping parameters of the model in terms of the well known stiffness parameters of the rod and the retardation time constants defined as the ratios of bulk and shear viscosities to the respective elastic moduli. We briefly discuss the range of validity of the Kelvin–Voigt model and illustrate its behaviour for large bending deformations with a numerical example.

PVC based membranes of disodium salt of porphyrin 3,7,12,17-tetramethyl-8, 13-divinyl 2,18-porphine dipropionic acid (I) as ionophore with sodium tetra phenyl borate (NaTPB) as anion excluder and dibutyl phthalate (DBP), dioctyl phthalate (DOP), dibutyl butyl phosphonate (DBBP), tris(2- ethyl hexyl)phosphate (TEP), tri-n-butylphosphate (TBP) and 1- chloronaphthalene (CN) as plasticizing solvent mediators were prepared and constructed for determination of Zn(II). The PVC based membrane of (I) with DBBP as plasticizer and having anion excluder, NaTPB in the ratio PVC: I: NaTPB: DBBP (150: 10: 2: 200) gave the best results in terms of working concentration range (1.3×10-5-1.0 ×10-1M) with a Nernstian slope (30.0 mV/decade of activity). The useful pH range of the sensor is 3.0 –7.4, beyond which a drift in potential was observed. The response time of the sensor is 10s and the lifetime was about 2 months during which it could be used without any measurable divergence. It had good stability and reproducibility. The membrane worked satisfactorily in non-aqueous medium up to 40% (v/v) non-aqueous content. The selectivity coefficient values indicate that the electrode is highly selective for Zn2+ over a number of other cations except Na+ and Cd2+. Although Na+ and Cd2+ are likely to cause some interference, they would not interfere if present at the concentrations < 1 ×10-5 and < 5 ×10-5 M, respectively. The electrode has been used as an indicator electrode to determine the end point in the potentiometric titration of Zn2+ with EDTA.