Voyage en Suisse et en Italie, fait avec l'armée de réserve

Analyse: Description du canton de Valais aux pages p. 91 et suivantes

Therapeutic Anticoagulant Does not Modify Thromboses Rate Vein after Venous Reconstruction Following Pancreaticoduodenectomy

Recommendations for anticoagulation following major venous reconstruction for pancreatic adenocarcinoma (PA) are not clearly established. The aim of our study was to find out the relation between postoperative anticoagulant treatment and thrombosis rate after portal venous resection. Materials and methods. Between 1986 and 2006, twenty seven portal vein resections were performed associated with pancreaticoduodenectomies (n = 27) (PD).We defined four types of venous resection: type I was performed 1 cm above the confluent of the superior mesenteric vein (SMV) (n = 12); type II lateral resection and venorrhaphy at the level of the confluent SMV (n = 12); type III (n = 1) resulted from a primary end-to-end anastomosis above confluent and PTFE graph was used for reconstruction for type IV (n = 2). Curative anticoagulant treatment was always indicated after type IV (n = 2) resection, and after resection of type II when the length of venous resection was longer than ≥2 cm. Results. Venous thrombosis rate reached: 0%, 41%, and 100% for type I, II, IV resections, respectively. Among them four patients received curative anticoagulant treatment. Conclusion. After a portal vein resection was achieved in the course of a PD, curative postoperative anticoagulation does not prevent efficiently the onset of thrombosis

Tests of a 3D Printed BPM with a Stretched Wire and with a Particle Beam

International audienceWe have successfully printed a beam position monitor using 3D printing. After ultra-high vacuum testing and initial measurements with a network analyser we now reports on tests of this BPM using the stretched wire method. The BPM has been installed on a test stand with a wire going through it and electrical pulses have been sent. The signal measured on the pick-ups was compared to that of two conventional BPMs and shows no anomaly specific to the 3D printed BPMs. Following the success of these tests we have also installed this BPM in a beam line at the PhotoInjector at LAL (PHIL). We show that it can give position measurements with an accuracy comparable to that of other BPMs

Lens Calibration for Beam Size Monitors at ThomX

International audienceThomX is a novel compact X-ray light source, utilising a laser and 50 MeV electron storage ring to produce X-ray photons via Compton scattering. Screens, observed by zoom lenses and optical cameras, can be used to monitor the transverse beam profile at various points. An issue with the implementation of this system is that after adjusting the zoom one needs to recalibrate the the optical system, measuring the resolution of the optical system and deducing the transformation from pixel space observed on the camera to geometrical space in the laboratory. To calibrate and measure the resolution limit of the cameras a USAF 1951 resolution chart that can be moved into or out of the screen position is used. We will report on and demonstrate the use of open source computer vision libraries to compute this calibration, and the affine transformation between the camera image plane and the screens can be deduced. We will also comment on how consumer available Canon EF mount lenses may be used as a remote controllable optical system

Surgery of small bowel melanoma metastases in the era of efficient medical therapies

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Characterization of the Electron Beam Visualization Stations of the ThomX Accelerator

International audienceWe present an overview of the diagnostics screens stations - named SSTs - of the ThomX compact Compton source. ThomX is a compact light source based on Compton backscattering. It features a linac and a storage ring in which the electrons have an energy of 50 MeV. Each SST is composed of three screens, a YAG:Ce screen and an Optical Transition Radiation (OTR) screen for transverse measurements and a calibration target for magnification and resolution characterisation. The optical system is based on commercial lenses that have been reverse-engineered. An Arduino is used to control both the aperture and the focus remotely, while the magnification must be modified using an external motor. We report on the overall performance of the station as measured during the first steps of beam commissioning and on the optical system remote operations

HVEM has a broader expression than PD-L1 and constitutes a negative prognostic marker and potential treatment target for melanoma

International audienceHVEM (Herpes Virus Entry Mediator) engagement of BTLA (B and T Lymphocyte Attenuator) triggers inhibitory signals in T cells and could play a role in evading antitumor immunity. Here, HVEM expression levels in melanoma metastases were analyzed by immunohistochemistry, correlated with overall survival (OS) in 116 patients, and validated by TCGA transcriptomic data. Coincident expression of HVEM and its ligand BTLA was studied in tumor cells and tumor-infiltrating lymphocytes (TILs) by flow cytometry (n = 21) and immunofluorescence (n = 5). Candidate genes controlling HVEM expression in melanoma were defined by bioinformatics studies and validated by siRNA gene silencing. We found that in patients with AJCC stage III and IV melanoma, OS was poorer in those with high HVEM expression on melanoma cells, than in those with a low expression, by immunohistochemistry (p = .0160) or TCGA transcriptomics (p = .0282). We showed a coincident expression of HVEM at the surface of melanoma cells and of BTLA on TILs. HVEM was more widely expressed than PD-L1 in melanoma cells. From a mechanistic perspective, in contrast to PDL1, HVEM expression did not correlate with an IFNγ signature but with an aggressive gene signature. Interestingly, this signature contained MITF, a key player in melanoma biology, whose expression correlated strongly with HVEM. Finally, siRNA gene silencing validated MITF control of HVEM expression. In conclusion, HVEM expression seems to be a prognosis marker and targeting this axis by checkpoint-inhibitors may be of interest in metastatic melanoma

First Electron Beam of the ThomX Project

International audienceThe ThomX accelerator beam commissioning phase is now ongoing. The 50 MeV electron accelerator complex consists of a 50 MeV linear accelerator and a pulsed mode ring. It is dedicated to the production of X-rays by Compton backscattering. The performance of the beam at the interaction point is demanding in terms of emittance, charge, energy spread and transverse size. The choice of an undamped ring in pulsed mode also stresses the performance of the beam from the linear accelerator. Thus, commissioning includes a beam based alignment and a simulation/experimental matching procedure to reach the X-ray beam requirements. We will present the first 50 MeV electron beam obtained with ThomX and its characteristics