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In radiotherapy, X-ray or heavy ion beams target tumors to cause damage to their cell DNA. This damage is mainly induced by secondary low energy electrons. In this paper, we report the DNA molecular breaks at the atomic level as a function of electron energy and types of electron interactions using of Monte Carlo simulation. The number of DNA single and double strand breaks are compared to those from experimental results based on electron energies. In recent years, DNA atomistic models were introduced but still the simulations consider energy deposition in volumes of DNA or water equivalent material. We simulated a model of atomistic B-DNA in vacuum, forming 1122 base pairs of 30 nm in length. Each atom has been represented by a sphere whose radius equals the radius of van der Waals. We repeatedly simulated 10 million electrons for each energy from 4 eV to 500 eV and counted each interaction type with its position x, y, z in the volume of DNA. Based on the number and types of interactions at the atomic level, the number of DNA single and double strand breaks were calculated. We found that the dissociative electron attachment has the dominant effect on DNA strand breaks at energies below 10 eV compared to excitation and ionization. In addition, it is straightforward with our simulation to discriminate the strand and base breaks as a function of radiation interaction type and energy. In conclusion, the knowledge of DNA damage at the atomic level helps design direct internal therapeutic agents of cancer treatment.

We are interested in service contracts for spare parts. We introduce a new performance measure, XLD (extreme long down), that limits the number of deliveries that are later than an agreed threshold during the contract period. We consider a single item, single location stockpoint serving multiple systems where demand is satisfied in an alternative way if the stockpoint is out of stock. Using a finite horizon Markov decision process, we derive the optimal spare parts inventory policy for meeting the contract at minimum costs. We prove that a state-dependent and time-dependent base stock policy is optimal. We also prove that the optimal base stock level is non-increasing in the number of allowed extreme long downs in the remaining contract period and that the optimal base stock level decreases at most by one unit per step. We formulate three heuristics for our finite horizon problem. These heuristics are a translation of heuristics commonly used for other service measures than the XLD measure. We assess their performance in comparison to the optimal policy. The results of our numerical study show that Heuristic 3, a myopic heuristic, is the best performing with an average optimality gap of 4.5 % and an optimality gap lower than 5 % in 81 % of the instances. The maximum optimality gap is very high for all three heuristics, showing that important savings can be made by taking into account the actual contract performance and the remaining contract duration in stocking decisions.

Traffic flow at urban intersections fluctuates randomly throughout the day. It depends on several dynamic factors and requires adequate regulation and adaptable control strategies in particular for traffic signals regulation. This paper deals with this problem, and our proposal focuses on the adaptive management of traffic lights within urban intersections. To do so, Timed Synchronized Petri Nets (TSPNs) models are first developed to model and study the system behaviour. Then a real-time adaptive control strategy is proposed for traffic regulation within urban signalized intersections. The control logic is shared between two communicating components of the system. The slaves (TSPNs sub-models) control the traffic signals displays, phases transitions, and traffic flow fluctuations. The master (controller) decides and selects the next phase that should be serviced and determines its green light duration. Due to the used modularity approach, the developed models decrease the modelling complexity, and more importantly, they can be adapted easily to a cluster of intersections. Furthermore, various traffic signal control strategies could be implemented using these models. Moreover, some simulations are performed, and the obtained results are analysed and discussed. Our control strategy is validated through these simulation results.

Collision induced dissociation of triple quadrupole mass spectrometer (CID-QqQ) and high-energy collision dissociation (HCD) of Orbitrap were compared for four neuropeptides Y Y1 (NPY Y1) receptor antagonists and showed similar qualitative fragmentation and structural information. Orbitrap high resolution and high mass accuracy HCD fragmentation spectra allowed unambiguous identification of product ions in the range 0.04–4.25 ppm. Orbitrap mass spectrometry showed abundant analyte-specific product ions also observed on CID-QqQ. These results show the suitability of these product ions for use in quantitative analysis by MRM mode. In addition, it was found that all compounds could be determined at levels >1 μg L−1 using the QqQ instrument and that the detection limits for this analyzer ranged from 0.02 to 0.6 μg L−1. Overall, the results obtained from experiments acquired in QqQ show a good agreement with those acquired from the Orbitrap instrument allowing the use of this relatively inexpensive technique (QqQ) for accurate quantification of these compounds in clinical and academic applications.

Scheduling production in open-pit mines is characterized by uncertainty about the metal content of the orebody (the reserve) and leads to a complex large-scale mixed-integer stochastic optimization problem. In this paper, a two-phase solution approach based on Rockafellar and Wets’ progressive hedging algorithm (PH) is proposed. PH is used in phase I where the problem is first decomposed by partitioning the set of scenarios modeling metal uncertainty into groups, and then the sub-problems associated with each group are solved iteratively to drive their solutions to a common solution. In phase II, a strategy exploiting information obtained during the PH iterations and the structure of the problem under study is used to reduce the size of the original problem, and the resulting smaller problem is solved using a sliding time window heuristic based on a fix-and-optimize scheme. Numerical results show that this approach is efficient in finding near-optimal solutions and that it outperforms existing heuristics for the problem under study.

Resume La morsure de serpent constitue une forme grave d’envenimations. Au Maghreb, les syndromes viperins sont le fait de la vipere Lebetine ( Vipera lebetina ), la vipere a cornes ou vipere des sables ( Cerastes cerastes ), parfois Bitis ou Echis sp. Le tableau clinique associe des anomalies biologiques de l’hemostase et un œdeme local avec possibilite de syndrome de loge et de necrose. Les protocoles therapeutiques associent une prise en charge medicochirurgicale symptomatique et une immunotherapie specifique.

The open-pit mine production scheduling problem (MPSP) deals with the optimization of the net present value of a mining asset and has received significant attention in recent years. Several solution methods have been proposed for its deterministic version. However, little is reported in the literature about its stochastic version, where metal uncertainty is accounted for. Moreover, most methods focus on the mining sequence and do not consider the flow of the material once mined. In this paper, a new MPSP formulation accounting for metal uncertainty and considering multiple destinations for the mined material, including stockpiles, is introduced. In addition, four different heuristics for the problem are compared; namely, a tabu search heuristic incorporating a diversification strategy (TS), a variable neighborhood descent heuristic (VND), a very large neighborhood search heuristic based on network flow techniques (NF), and a diversified local search (DLS) that combines VND and NF. The first two heuristics are extensions of existing methods recently proposed in the literature, while the last two are novel approaches. Numerical tests indicate that the proposed solution methods are effective, able to solve in a few minutes up to a few hours instances that standard commercial solvers fail to solve. They also indicate that NF and DLS are in general more efficient and more robust than TS and VND.

Urbanism development makes cities more congested and then more polluted. Hence, the primary factor that influences the urban environment directly is traffic flow. Therefore, this complex system requires efficient control methods to reduce its impact at urban zones, in particular for traffic light within intersections. In this paper, a dynamic control strategy of traffic signal at urban intersections is proposed. This strategy is based on Knapsack-problem and enables to manage the green light duration autonomously following the queue length for each road lane. The dynamic behavior of this system is considered as a discrete event system. Consequently, a modular Timed Synchronized Petri Net (TSPN) model is developed. Depending on real-time communication, the TSPN modules represent the ”slaves”, and the responsive controller represents the ”master” that manage optimally the vehicles evacuation at the intersection. Moreover, for the system dependability, some interesting properties of the system are checked through the developed Petri net model. SUMO based simulations are performed and analyzed to validate the proposed approach. Through the performed simulations and the analysis of the proposed dynamic control approach and findings show the efficiency of our control policy about smooth traffic increasing and environmental impact reducing.

A hyper-heuristic refers to a search method or a learning mechanism for selecting or generating heuristics to solve computational search problems. Operating at a level of abstraction above that of a metaheuristic, it can be seen as an algorithm that tries to find an appropriate solution method at a given decision point rather than a solution. This paper introduces a new hyper-heuristic that combines elements from reinforcement learning and tabu search. It is applied to solve two complex stochastic scheduling problems arising in mining, namely the stochastic open-pit mine production scheduling problem with one processing stream (SMPS) and one of its generalizations, SMPS with multiple processing streams and stockpiles (SMPS+). The performance of the new hyper-heuristic is assessed by comparing it to several solution methods from the literature: problem-specific algorithms tailored for the two problems addressed in the paper and general hyper-heuristics, which use only limited problem-specific information. The computational results indicate that not only is the proposed new hyper-heuristic approach superior to the other hyper-heuristics, but it also provides results that are comparable to or improve on the results obtained by the state-of-the-art problem-specific methods.

Objectifs L’antibioprophylaxie est l’une des mesures dont l’impact sur la prevention des Iso (infection du site operatoire) a ete quantifie avec le plus de precision : dans les interventions chirurgicales propres et propres-contaminees, en rappelant que les Iso entrainent une majoration du cout de la prise en charge et une mauvaise perception des soins par l’usager. Evaluer l’observance des recommandations en antibioprophylaxie, en chirurgie urologique. Methodes Cent soixante-huit patients operes en 2018 et relevant d’une antibioprophylaxie ont ete tires au sort et ayant beneficie au bloc operatoire d’une chirurgie scrotale, de varicocele, d’une RTUP, RTUV, de traitement endoscopique ou percutane de lithiase, de cystectomie, de prostatectomie radicale et de nephrectomie, relevant toutes d’une antibioprophylaxie. Sur cette base (168 patients), le respect des recommandations en antibioprophylaxie de notre service et de la Societe francaise d’anesthesie et reanimation (SFAR) a ete recherche (resume sur Tableau 1 ). Nous avons etudie la conformite des indications et de la realisation de l’antibioprophylaxie en ciblant apres concertation avec l’equipe d’anesthesie et les equipes chirurgicales, la nature du produit, le moment de l’administration et la duree du traitement. Resultats La repartition des malade en fonction du type de chirurgie est resumee sur la Fig. 1 . La conformite globale etait de 58,3 % et les autres parametres sur le Tableau 2 . Conclusion Les recommandations en antibioprophylaxie sont imparfaitement appliquees, notamment pour ce qui concerne le moment d’administration. Des efforts doivent etre poursuivis tant en termes d’observance des recommandations que d’enregistrement de l’administration et evalues de facon repetee.

One of the major routes of communication from the peripheral systems to the hypothalamus, the core structure of body homeostasis, is the humoral transmission through the blood-brain barrier (BBB). The BBB cultures are the in vitro model of choice to depict the mechanisms behind blood-brain interplay. Still, this strategy excludes the integration of the brain tissue response and, therefore, the resulting output might be limited. In this study, two in vitro assays were established: BBB coculture model and hypothalamic organotypic cultures. The combination of these two assays was used as a platform to address the two critical steps in the humoral transmission through the BBB to the brain: blood-BBB/BBB-brain. The in vitro model of the BBB was performed according to a coculture system using a brain microvascular endothelial cell line (bEnd.3) and primary astrocytes. The expression of junctional molecules as claudin-5, ZO-1, occludin and VE-cadherin was observed in the bEnd.3 cell-cell contact, confirming the BBB phenotype of these endothelial cells. Moreover, the transendothelial electrical resistance (TEER) values (71.1±9.4Ω× cm(2)) and the permeability coefficients (Pe) obtained in the transendothelial flux test (3.3±0.11×10(-6)cm/sec) support high integrity of the established barrier. The hypothalamic organotypic cultures were prepared from 8-days-old C57Bl/6 mice brains, based on the air-medium interface culture method. High cell viability (82±9.6%) and a dense neuronal network were achieved. The stimulation with dexamethasone resulted in an increased neuropeptide (NPY) expression, confirming the responsiveness of the neuronal system of these organotypic cultures. After optimization and characterization of each assay, the functionality of the platform was validated through the evaluation of the hypothalamic response to deep wound encompassing skin and muscle in mice. Results allowed to identify increased NPY activity in hypothalamic slices in response to peripheral signals within the plasma from wounded animals when compared with non-injured animals after surpassing and/or interacting with the BBB. This differential NPY response between the different animal conditions validated the functionality of the in vitro platform. In conclusion, this approach can be greatly anticipated as a useful tool for studying biologic or pharmacological circulating molecules and their impact on the hypothalamic activity.

Resume Introduction L’association hypertension arterielle (HTA) et diabete de type 2 (DT2) est frequente. Elle potentialise le risque de deces et de complications cardiovasculaires. De ce fait, la prevention passe par un bon equilibre de la pression arterielle (PA) et du diabete. But de l’etude Evaluer la sensibilite de la mesure clinique de la PA dans l’evaluation du controle tensionnel chez l’hypertendu diabetique, l’apport de la mesure ambulatoire de la pression arterielle (MAPA), ainsi que les facteurs associes a un mauvais controle tensionnel chez cette population de malades. Patients et methodes Il s’agit d’une etude prospective sur 4 mois, portant sur des patients hypertendus, DT2 connus et traites, recrutes a partir de la consultation du service de cardiologie du centre hospitalier universitaire de Marrakech (Maroc). Tous les patients ont beneficie d’un examen physique complet avec la mesure de la PA aux deux bras, lors de deux consultations differentes au minimum, et d’une MAPA sur 24 heures. Resultats L’etude a ete menee chez 60 patients (26 hommes et 34 femmes ; sex-ratio : 0,76) d’un âge moyen de 63,0 ± 6,4 ans (48–75 ans). L’HTA etait bien controlee chez 35 (58,3 %) patients seulement. Le taux de concordance entre la mesure clinique de la PA et la MAPA etait de 62 %. Environ 13 % des patients, juges controles lors de la mesure clinique de la PA, ne l’etaient pas a la MAPA. Les sujets ayant une HTA mal controlee etaient significativement plus âges ( p = 0,01) et plus souvent de sexe masculin ( p = 0,002). La dysregulation nocturne de la PA et un pic matinal de PA ont ete notes dans les deux groupes, bien controles et mal controles (34 % et 48 % versus 32 % et 48 %, respectivement ; p = NS). Conclusion L’HTA de nos patients DT2, au Maroc, est le plus souvent mal controlee. Nous soulignons a travers ce travail, l’apport de la MAPA chez tout patient hypertendu diabetique dans l’evaluation du controle tensionnel, et donc pour l’adaptation therapeutique, ainsi que son interet pronostic.

Designing new biomaterials that can modulate the inflammatory response instead of attempting just to reduce it constitutes a paradigm change in regenerative medicine. This work aimed to investigate the capacity of an immunomodulatory biomaterial to enhance bone regeneration. For that purpose we incorporated a molecule with well-established pro-inflammatory and pro-healing roles, fibrinogen, in chitosan scaffolds. Two different incorporation strategies were tested, leading to concentrations of 0.54±0.10mg fibrinogen g(-1) scaffold immediately upon adsorption (Fg-Sol), and 0.34±0.04mg fibrinogen g(-1) scaffold after washing (Fg-Ads). These materials were implanted in a critical size bone defect in rats. At two months post-implantation the extent of bone regeneration was examined by histology and the systemic immune response triggered was evaluated by determining the percentages of myeloid cells, T and B lymphocytes in the draining lymph nodes. The results obtained indicate that the fibrinogen incorporation strategy conditioned the osteogenic capacity of biomaterials. Fg-Ads scaffolds led to more bone formation, and the presence of Fg stimulated angiogenesis. Furthermore, animals implanted with Fg-Ads scaffolds showed significant increases in the percentages of B lymphocytes and myeloid cells in the draining lymph nodes, while levels of T lymphocytes were not significantly different. Finally, a significant increase in TGF-β1 was detected in the plasma of animals implanted with Fg-Ads. Taken together the results presented suggest a potential correlation between the elicited immune response and biomaterial osteogenic performance.

The judge assignment problem consists in finding an assignment satisfying the competition rules (hard constraints) and meeting, as much as possible, the competition organizers objectives (soft constraints). In this paper, various specific real-world constraints found in organizing academic competitions are handled. We tackle the corresponding problem with a metaheuristic approach based on Tabu search. The numerical results indicate that very good solutions can be generated in reasonable computational times.

In the city of El Jadida, disposal of untreated wastewater in the ocean has a negative impact on the environment and the health of the populations who live along the urban effluents. The evaluation of parasites, such as helminths that are carried in the residual water, is a first step in understanding the health risks they engender. This evaluation requires an effective and appropriate methodology of analysis that allows the detection of helminth eggs in different environments. The parasitological makeup of wastewater in the city of El Jadida and the marine environment where it is discharged was examined. A significant level of biological pollution was detected in the main sewer of the city and in the coastal areas near the discharge points. The presence of helminth eggs at the coastal stations located further away from the overflow pipes proves that the parasitic mass can and does move. Qualitatively, Ascaris eggs were omnipresent through out the year in all the monitoring stations along the main sewer and along the coast. Thus a part of this work evaluates the risk of untreated wastewater discharge to spreading of ascariasis along the discharge area of the city. This study is a copro-epidemiological evaluation on a group of children living near the area of wastewater effluents. For a comparative approach, a control group has been selected from a neighbourhood far from the discharge area. The incidence of ascariasis was 18.1% in the study group and 1% in the control group. The risk attributable to wastewater in transmitting ascariasis to exposed children was about 17%. Boys, particularly those between the ages of 7 and 10, appeared to be the most vulnerable to ascariasis exposure. The results we obtained demonstrate that proximity to untreated wastewater poses a real health hazard.

Attention has been focused recently on the use of Moroccan black oil shale as the raw material for production of a new type of adsorbent and its application to U and Th removal from contaminated wastewaters. The purpose of the present work is to provide a better understanding of the composition and structure of this shale and to determine its natural content in uranium and thorium. A black shale collected from Timahdit (Morocco) was analyzed by powder X-ray diffraction and SEM techniques. It was found that calcite, dolomite, quartz and clays constitute the main composition of the inorganic matrix. Pyrite crystals are also present. A selective leaching procedure, followed by radiochemical purification and alpha-counting, was performed to assess the distribution of naturally occurring radionuclides. Leaching results indicate that 238U, 235U, 234U, 232Th, 230Th and 228Th have multiple modes of occurrence in the shale. U is interpreted to have been concentrated under anaerobic conditions. An integrated isotopic approach showed the preferential mobilization of uranium carried by humic acids to carbonate and apatite phases. Th is partitioned between silicate minerals and pyrite.

Bone and nacre feature highly orchestrated biomineralised structures. They are calcified structures that share an intervening organic matrix laid by specialized cells, bone cells in vertebrates and epithelial mantle cells in molluscs. Organic framework provides a scaffold for crystallisation and directs mineralisation. Bone and shell likely undergo self-reparation when damaged, clues to the presence in these mineralised structures of signal molecules, targeting the cells involved in their renewal. In molluscs, calcium carbonate crystallise under two mineral polymorphs, aragonite or calcite. Sudo et al. [22] reported two exclusive proteins in the shell of a bivalvia molluscan, Pinctada fucata, MSI 60 in aragonite and MSI 31 in calcite. We built up specific antibodies and experimented immunohistochemistry in Haliotis. These tools revealed the presence of Pinctada-like proteins within Haliotis mantle cells, in a zonation consistent with shell matrix mineralisation control involvement. Another facet of matrix-mediated biomineralisation control arises from bone and nacre interactivity. In vivo experiments of nacre implantation in sheep and rabbit established the biocompatibilty of nacre and bone. The nacreous part from the shell of Pinctada, a bivalve mollusc, was implanted as bone device in sheep and showed that nacre passes bone acceptance. Nacre implants were not subjected to intolerance reaction and the recipient bone provided with nacre underwent a sequence of bone regeneration within an osteoprogenitor-rich cell layer. The water-soluble organic matrix was extracted from powdered nacre by a gentle non-decalcifiying process. Three mammalian cell types, fibroblasts (human), bone marrow stromal cells (rat) and pre-osteoblasts (mouse) were used to characterize in vitro the effect of nacre water-soluble matrix on mammal bone cell lineage. In vitro studies provided evidence for the presence, in nacre organic matrix, of signal molecules responsible for the recruitment of mammal cells in the osteogenic pathway and bone cell activation undergoing a complete sequence of mineralisation. Retrieving like-proteins in shell matrix of molluscs from distant taxa and bone nacre interactivity provides convergent data supporting the conservation of molecular signals for biomineralisation control within the organic framework of biomineralised structures. To cite this article: C. Milet et al., C. R. Palevol 3 (2004).

We developed a bone-defect model in the vertebrae of sheep. Forty four cavities were prepared in the upper lumbar vertebrae of 11 sheep using a biopsy trocar via a posterior-lateral extracanal percutaneous route and the location was monitored by radiology with a brilliance amplifier. The cavities were 3 mm in diameter. The histological study was performed on 15 cavities which were left empty to give reference data for the model. Histological and histomorphometry results showed that 67% of the surface area of the empty cavities was still empty 3 months after their preparation. Thus, the natural regenerative capacity of vertebral trabecular bone is limited. We performed preliminary percutaneous injections of polymethylmethacrylate (PMMA) and nacre powder to assess whether this bone-defect model would be suitable for further studies on bone repair. Cavities were successfully filled with nacre powder (21 cavities) or PMMA (8 cavities) while monitoring the process by interventional radiology. The experimental sheep vertebrae defect system is reproducible and appears to be a suitable model for testing injectable biomaterials for treating bone loss.

There is frequently a loss of vertebral bone due to disease or aging. Nacre (mother of pearl from the oyster Pinctada maxima) stimulates bone cell differentiation and bone formation in vitro and in vivo. Experimental bone defects were prepared in the vertebrae of sheep and used to test the suitability of nacre as an injectable osteogenic biomaterial for treating vertebral bone loss. Twenty-one cavities were prepared in the first four upper lumbar vertebrae of 11 sheep and filled with nacre powder. The lumbar vertebrae were removed after 1 to 12 weeks, embedded undecalcified in methacrylate, and processed for histological studies. The nacre slowly dissolved and the experimental cavities contained a large active cell population. By 12 weeks, the experimental cavity was occupied by newly matured bone trabeculae in contact with or adjacent to the dissolving nacre. The functional new bone trabeculae were covered with osteoid lined with osteoblasts, indicating continuing bone formation. The in vitro study on rat bone marrow explants cultured with a water-soluble extract of the nacre organic matrix also resulted in the stimulation of osteogenic bone marrow cells with enhanced alkaline phosphatase activity. Thus, both the in vivo and in vitro findings suggest that nacre contains one or more signal molecules capable of activating osteogenic bone marrow cells.

Palmaria palmata (Dulse) is a red seaweed that may be a potential protein source in the human diet. Its protein content, amino acid composition, and protein digestibility were studied with algae collected every month over a 1-year period. Significant variations in protein content were observed according to the season: The highest protein content (21.9 +/- 3.5%) was found in the winter-spring period and the lowest (11.9 +/- 2.0%) in the summer-early autumn period. Most of the essential amino acids were present throughout the year. After 6-hour in vitro digestion in a cell dialysis using porcine pepsin and porcine pancreatin, the digestibility of proteins from Palmaria palmata crude powder, represented by dialyzed nitrogen, was estimated at 29.52 +/- 1.47%. Relative digestibility was 56%, using casein hydrolysis as 100% reference digestibility. In vitro digestibility of proteins extracted in water was analyzed by sodium dodecylsulfate polyacrylamide gel electrophoresis using either bovine trypsin, bovine chymotrypsin, pronase from Streptomyces griseus, or human intestinal juice. Dulse proteins were hydrolyzed to a limited extent, which confirmed a rather low digestibility. Hydrolysis rate was higher with trypsin and lower with chymotrypsin compared with the two other enzymatic systems, pronase and intestinal juice, respectively. The association of algal powder and protein extract to casein and bovine serum albumin, respectively, produced a significant decrease in the hydrolysis rate of the standard proteins. In conclusion, the digestibility of Palmaria palmata proteins seems to be limited by the algae non-proteic fraction.

A 77-year-old man was referred in January 2003 for an intrahepatic biloma, occurring after a left lobectomy and limited resection of segment IV and V because of metastatic colonic adenocarcinoma. Previous attempts at endoscopic and percutaneous transhepatic drainage were unsuccessful due to the inability to pass a guidewire through the biloma. In both procedures, the guidewire wrapped itself within the biloma, which was related to an injury of the right intrahepatic duct near the hepatic hilum (Fig. 1). Therefore, a combined percutaneous approach was used to provide external and internal drainage of the biloma. The procedure was performed under fluoroscopic guidance. The radiologist (D.O.) introduced a guidewire (Angled Radifocus Guide Wire; Terumo Corp, Tokyo, Japan) into the biloma through a guide manipulation catheter (Torcon NB Advantage Kumpe Selective Wire; Cook, Inc, Bjaeverskov, Denmark). The endoscopist (J-F.B.) used a Dormia basket catheter (MTW Endoskopie Inc, Wesel, Germany) inserted over a guidewire introduced via endoscopy into the biloma. While the radiologist attempted successive approaches with the guide manipulation catheter, the endoscopist tried and finally caught hold of the flexible tip of the guidewire (Figs. 2A and B). Once grasped within the basket, the guidewire was easily pulled through the common bile duct and the endoscope (Fig. 2C). Internal/external drainage was performed by percutaneous introduction, over the tightened guidewire, of a 40-cm long, locking pigtail 8F drain (Cook, Inc, Bjaeverskov, Denmark) through the main papilla, into the duodenum (Fig. 2D). Three weeks after the procedure, the drainage catheter was clamped and follow-up CT scan and endoscopic

A 56-year-old woman was referred because of anemia with recurrent melena. The duodenoscopy revealed a voluminous pedunculated submucosal tumor adjacent to the major papilla (A). Standard forceps biopsy specimens were negative for malignancy. Abdominal CTshowed a mass located within the duodenum that appeared solid with central hypodensity (B). There was no evidence of a pancreatic or retroperitoneal mass or lymphadenopathy. Despite the large volume, the tumor was resected endoscopically by electrosurgical snare polypectomy. Arterial bleeding occurred immediately, which was controlled with placement of 3 clips (C). The excised tumor measured 4 2 3 cm (D). The opening of the major papilla was not touched, despite its close location. The outcome