909 resultados para FLEXIBLE DOCKING


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Objective: Our study aimed at assessing the role of flexible bronchoscopy (FB) in improving diagnosis and management of children’s respiratory conditions in the pediatric unit of FB, newly created and unique in Tunisia. Methods: Retrospective study including all the FB achieved in our pediatric unit from 2009 to 2014. Results: We performed 365 FB in 333 patients aged 46 months on average (1 month - 15 years), often under conscious anesthesia (81.6%). FB was performed for diagnostic purposes in 341 cases and for therapeutic purposes in 24 cases. Eight anatomical abnormalities were revealed in 22 patients. An intraluminal bronchial obstruction was found in 71 FB, mainly due to a foreign body (n=36). A vascular anomaly was responsible for nine cases out of 17 extraluminal obstructions. Airways malacia was observed in 60 FB. Bronchoalveolar lavage was performed in 196 cases. It was determinant in 43.9% of the cases. FB was of great diagnostic value in 74.8% of the cases. It influenced the management of the patients in 58% of the cases. The FB for therapeutic purposes was beneficial in all cases. Few complications occurred (5.5%). Conclusion: FB is a safe tool providing precious diagnostic and/or therapeutic help for the clinician. Keywords:

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The B cell CLL/lymphoma-2 (Bcl-2) family is functionally classified as either anti-apoptotic or pro-apoptotic, and the regulation of its interactions dictates survival or commitment to apoptosis. Bcl-2 family is also implicated in a wide range of diseases. In some types of cancers, including lymphomas and epithelial cancers, protein overexpression of anti-apoptotic Bcl-2 family, such as the Bcl-2 protein is indicative of cancer in an advanced stage, with a poor prognosis and resistant to chemotherapy [1]. Several reports indicate that mushrooms have the ability to promote apoptosis in tumour cell lines, but the mechanism of action is not fully understood. Inhibition of the interaction between Bcl-2 (anti-apoptotic protein) and proapoptotic proteins could be an important step in the mechanism of mushroom induced apoptosis. Therefore, the discovery of compounds with the capacity to inhibit Bcl-2 is an ongoing research topic on cancer therapy. In this work, docking studies were performed using a dataset of 40 low molecular weight (LMW) compounds present in mushrooms. The docking software AutoDock 4 was used and docking studies were performed using 5 selected Bcl-2 crystal structures as targets. Compounds with the lowest predicted binding energy (predΔG) are expected to be the more potent inhibitors. Among the tested compounds, steroids presented the lowest predΔG with several exhibiting values below -9 kcal/mol. The results are corroborated by several reports that state that steroids induce apoptosis in several tumor cells. It is thus feasible that they might act by preventing Bcl-2 from forming complexes with the respective proapoptotic protein interaction partners, namely Bak, Bax, and Bim. Moreover, previous studies on our research group demonstrated that 48 h treatment of MCF-7 cells (breast carcinoma) with Suillus collinitus methanolic extract caused a decrease in Bcl-2, highlighting the antitumor potential of this mushroom species [2]. In conclusion, the process of apoptosis promoted by mushroom extracts may be related to the inhibition of Bcl-2 by the steroid derivatives herein studied. However, further studies are needed to confirm this hypothesis.

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We present a new radiation scheme for the Oxford Planetary Unified Model System for Venus, suitable for the solar and thermal bands. This new and fast radiative parameterization uses a different approach in the two main radiative wavelength bands: solar radiation (0.1-5.5 mu m) and thermal radiation (1.7-260 mu m). The solar radiation calculation is based on the delta-Eddington approximation (two-stream-type) with an adding layer method. For the thermal radiation case, a code based on an absorptivity/emissivity formulation is used. The new radiative transfer formulation implemented is intended to be computationally light, to allow its incorporation in 3D global circulation models, but still allowing for the calculation of the effect of atmospheric conditions on radiative fluxes. This will allow us to investigate the dynamical-radiative-microphysical feedbacks. The model flexibility can be also used to explore the uncertainties in the Venus atmosphere such as the optical properties in the deep atmosphere or cloud amount. The results of radiative cooling and heating rates and the global-mean radiative-convective equilibrium temperature profiles for different atmospheric conditions are presented and discussed. This new scheme works in an atmospheric column and can be easily implemented in 3D Venus global circulation models. (C) 2014 Elsevier Ltd. All rights reserved.

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Introduction: Flexible endoscopic treatment is one of the alternative approaches for the management of Zenker's diverticum. The present paper shows our short-term and long-term results with flexible endoscopic cricopharyngeal myotomy/septotomy. Patients and methods: A retrospective analysis of our experience in patients with Zenker's diverticulum treated using a flexible endoscope, assisted by a flexible diverticuloscope, between 2002 and 2015. Myotomy/septotomy was performed with a needle-knife papillotome under deep sedation or general anesthesia. Results: Among the 64 patients treated, two died within 10 days of surgery from causes not directly related to the procedure, and one presented with pharyngo-esophageal perforation, which recovered with conservative management at 47 days after admission. Four additional patients were lost to short-term follow-up. Among the 57 remaining patients, 52 had complete relief of dysphagia after 6 weeks. Eleven of these had recurrent symptoms on the mid and the long term. Eight were retreated with the same flexible endoscopic technique, one with a hybrid endoscopic approach, one with classical open surgery and one refused retreatment. After a mean follow-up of 2 years and a half, 33 of 37 patients reported absent or minimal dysphagia, controllable with punctual dietary restrictions. Conclusions: Flexible endoscopic treatment for Zenker's diverticulum is effective and safe. It represents an option on an equal footing to rigid endoscopy and classical open surgery and may also be used when the latter two are technically impracticable or contraindicated.

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Ligand-protein docking is an optimization problem based on predicting the position of a ligand with the lowest binding energy in the active site of the receptor. Molecular docking problems are traditionally tackled with single-objective, as well as with multi-objective approaches, to minimize the binding energy. In this paper, we propose a novel multi-objective formulation that considers: the Root Mean Square Deviation (RMSD) difference in the coordinates of ligands and the binding (intermolecular) energy, as two objectives to evaluate the quality of the ligand-protein interactions. To determine the kind of Pareto front approximations that can be obtained, we have selected a set of representative multi-objective algorithms such as NSGA-II, SMPSO, GDE3, and MOEA/D. Their performances have been assessed by applying two main quality indicators intended to measure convergence and diversity of the fronts. In addition, a comparison with LGA, a reference single-objective evolutionary algorithm for molecular docking (AutoDock) is carried out. In general, SMPSO shows the best overall results in terms of energy and RMSD (value lower than 2A for successful docking results). This new multi-objective approach shows an improvement over the ligand-protein docking predictions that could be promising in in silico docking studies to select new anticancer compounds for therapeutic targets that are multidrug resistant.

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In many major cities, fixed route transit systems such as bus and rail serve millions of trips per day. These systems have people collect at common locations (the station or stop), and board at common times (for example according to a predetermined schedule or headway). By using common service locations and times, these modes can consolidate many trips that have similar origins and destinations or overlapping routes. However, the routes are not sensitive to changing travel patterns, and have no way of identifying which trips are going unserved, or are poorly served, by the existing routes. On the opposite end of the spectrum, personal modes of transportation, such as a private vehicle or taxi, offer service to and from the exact origin and destination of a rider, at close to exactly the time they desire to travel. Despite the apparent increased convenience to users, the presence of a large number of small vehicles results in a disorganized, and potentially congested road network during high demand periods. The focus of the research presented in this paper is to develop a system that possesses both the on-demand nature of a personal mode, with the efficiency of shared modes. In this system, users submit their request for travel, but are asked to make small compromises in their origin and destination location by walking to a nearby meeting point, as well as slightly modifying their time of travel, in order to accommodate other passengers. Because the origin and destination location of the request can be adjusted, this is a more general case of the Dial-a-Ride problem with time windows. The solution methodology uses a graph clustering algorithm coupled with a greedy insertion technique. A case study is presented using actual requests for taxi trips in Washington DC, and shows a significant decrease in the number of vehicles required to serve the demand.

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La presente investigación aborda la producción social del hábitat como una coproducción, inherentemente colectiva, donde todos los agentes sociales intervienen pero de manera desigual. En la actualidad, los países de la región latinoamericana, han sido testigos de una expansión urbana acelerada, cuyas consecuencias son tanto beneficiosas como contraproducentes, beneficiosas porque se han creado nuevas fuentes de trabajo e ingreso para sus pobladores, acceso a la ciencia y la innovación y contraproducentes por la creciente desigualdad social, expresamente espacializada como informalidad urbana. En un mundo globalizado, donde las tecnologías digitales y el libre comercio, parecen haber borrado las fronteras geográficas, la informalidad urbana evidencia las rígidas divisiones sociales que persisten hasta nuestros días y que solo parecen agrandarse. La planeación urbana es rígida ante las necesidades siempre cambiantes y dinámicas de la región, las políticas públicas son creadas a partir de modelos económicos pensados para los países catalogados Primer Mundo mientras los profesionales del espacio (arquitectos y urbanistas) proponen abordajes aculturizados alejados de la escala local. Las intervenciones hasta ahora planteadas responden a una visión binaria (informal vs formal), lo que se traduce en soluciones parciales. Como producto de investigación se propone un análisis de estructuras red para desplegar la coproducción social del hábitat en toda su complejidad, entendiéndola como una serie de nodos co-relacionados, que solo pueden ser comprendidos por sus conexiones; esto con el fin de encaminar el discurso hacía una gestión flexible y democrática. Como caso de estudio se explora el asentamiento llamado Sierra Ventana, ubicado al sur de la ciudad mexicana Monterrey, en el estado de Nuevo León

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Poster presented at the Workshop on Flexible Models for Longitudinal and Survival Data with Applications in Biostatistics. University of Warwick, Coventry, UK, 27-29 July 2015