971 resultados para Steffen, Mart R. (Martin Robert), 1882-
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Adalimumab is a fully humanized recombinant anti-tumour-necrosis-factor (TNF-alpha) monoclonal antibody which has been approved for rheumatoid arthritis, active ankylosing spondylitis, psoriatic arthritis and Crohn's disease. We report a case of alopecia areata (AA) universalis occurring 6 months after administration of adalimumab monotherapy in a patient with a long-standing history of psoriatic arthritis and psoriasis. The diagnosis was confirmed by a scalp biopsy which showed a peribulbar infiltrate of both CD4+ and CD8+ T cells, CD1a+ dendritic cells as well as CD68+ and CD163+ macrophages. In addition, immunofluorescence staining for TNF-alpha was found in the mononuclear cell infiltrate. This case suggests a complex role of TNF-alpha in the induction of AA.
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With the rapid increase in approaches to pro- or anti-angiogenic therapy, new and effective methodologies for administration of cell-bound growth factors will be required. We sought to develop the natural hydrogel matrix fibrin as platform for extensive interactions and continuous signaling by the vascular morphogen ephrin-B2 that normally resides in the plasma membrane and requires multivalent presentation for ligation and activation of Eph receptors on apposing endothelial cell surfaces. Using fibrin and protein engineering technology to induce multivalent ligand presentation, a recombinant mutant ephrin-B2 receptor binding domain was covalently coupled to fibrin networks at variably high densities. The ability of fibrin-bound ephrin-B2 to act as ligand for endothelial cells was preserved, as demonstrated by a concomitant, dose-dependent increase of endothelial cell binding to engineered ephrin-B2-fibrin substrates in vitro. The therapeutic relevance of ephrin-B2-fibrin implant matrices was demonstrated by a local angiogenic response in the chick embryo chorioallontoic membrane evoked by the local and prolonged presentation of matrix-bound ephrin-B2 to tissue adjacing the implant. This new knowledge on biomimetic fibrin vehicles for precise local delivery of membrane-bound growth factor signals may help to elucidate specific biological growth factor function, and serve as starting point for development of new treatment strategies.
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Sexual selection theory largely rests on the assumption that populations contain individual variation in mating preferences and that individuals are consistent in their preferences. However, there are few empirical studies of within-population variation and even fewer have examined individual male mating preferences. Here, we studied a color polymorphic population of the Lake Victoria cichlid fish Neochromis omnicaeruleus, a species in which color morphs are associated with different sex-determining factors. Wild-caught males were tested in three-way choice trials with multiple combinations of different females belonging to the three color morphs. Compositional log-ratio techniques were applied to analyze individual male mating preferences. Large individual variation in consistency, strength, and direction of male mating preferences for female color morphs was found and hierarchical clustering of the compositional data revealed the presence of four distinct preference groups corresponding to the three color morphs in addition to a no-preference class. Consistency of individual male mating preferences was higher in males with strongest preferences. We discuss the implications of these findings for our understanding of the mechanisms underlying polymorphism in mating preferences.
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OBJECTIVES: To assess feasibility and outcomes of left atrial appendage (LAA) closure when using a patent foramen ovale (PFO) for left atrial access. Background: Because of the fear of entering the left atrium too high, using a PFO for left atrial access during LAA occlusion (LAAO) is generally discouraged. We report our single-center experience using a concomitant PFO for LAAO, thereby avoiding transseptal puncture. METHODS: LAAO was performed with local anesthesia and fluoroscopic guidance only (no echocardiography). The Amplatzer Cardiac Plug (ACP) was used in all patients. After LAAO, the PFO was closed at the same sitting, using an Amplatzer occluder through the ACP delivery sheath. Patients were discharged the same or the following day on dual antiplatelet therapy for 1-6 months, at which time a follow-up transesophageal echocardiogram (TEE) was performed. RESULTS: In 49 (96%) of 51 patients (35 males, age 70.9 ± 11.9 years), LAAO was successful using the PFO for left atrial access. In one patient, a long tunnel PFO precluded LAAO, which was performed via a more caudal transseptal puncture. In a second patient, a previously inserted ASD occluder precluded LAAO, which was abandoned because of pericardial bleeding. PFO closure was successful in all patients. Follow-up TEE was performed in 43 patients 138 ± 34 days after the procedure. It showed proper sitting of both devices in all patients. CONCLUSIONS: Using a PFO for LAAO had a high success rate and could be the default access in all patients with a PFO, potentially reducing procedural complications arising from transseptal puncture.
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Aims: To evaluate the accuracy and reproducibility of aortic annulus sizing using a multislice computed tomography (MSCT) based aortic root reconstruction tool compared with conventional imaging among patients evaluated for transcatheter aortic valve replacement (TAVR). Methods and results: Patients referred for TAVR underwent standard preprocedural assessment of aortic annulus parameters using MSCT, angiography and transoesophageal echocardiography (TEE). Three-dimensional (3-D) reconstruction of MSCT images of the aortic root was performed using 3mensio (3mensio Medical Imaging BV, Bilthoven, The Netherlands), allowing for semi-automated delineation of the annular plane and assessment of annulus perimeter, area, maximum, minimum and virtual diameters derived from area and perimeter (aVD and pVD). A total of 177 patients were enrolled. We observed a good inter-observer variability of 3-D reconstruction assessments with concordance coefficients for agreement of 0.91 (95% CI: 0.87-0.93) and 0.91 (0.88-0.94) for annulus perimeter and area assessments, respectively. 3-D derived pVD and aVD correlated very closely with a concordance coefficient of 0.97 (0.96-0.98) with a mean difference of 0.5±0.3 mm (pVD-aVD). 3-D derived pVD showed the best, but moderate concordance with diameters obtained from coronal MSCT (0.67, 0.56-0.75; 0.3±1.8 mm), and the lowest concordance with diameters obtained from TEE (0.42, 0.31-0.52; 1.9±1.9 mm). Conclusions: MSCT-based 3-D reconstruction of the aortic annulus using the 3mensio software enables accurate and reproducible assessment of aortic annulus dimensions.
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This paper is concerned with the modelling of storage configurations for intermediate products in process industries. Those models form the basis of algorithms for scheduling chemical production plants. Different storage capacity settings (unlimited, finite, and no intermediate storage), storage homogeneity settings (dedicated and shared storage), and storage time settings (unlimited, finite, and no wait) are considered. We discuss a classification of storage constraints in batch scheduling and show how those constraints can be integrated into a general production scheduling model that is based on the concept of cumulative resources.
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The purpose of the internet-based teachware mySCM is that students of economics, informatics and industrial engineering get familiar with quantitative methods for supply chain management. Input-output-relationships of various optimization methods can be detected by sampling input values, parameters, and alternative methods for the same problem. Students can gain extra benefits by passing so-called mini-exams that motivate active learning. mySCM can be used for free, round-the-clock, and any place where access to the Internet is available.
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Stray light contamination reduces considerably the precision of photometric of faint stars for low altitude spaceborne observatories. When measuring faint objects, the necessity of coping with stray light contamination arises in order to avoid systematic impacts on low signal-to-noise images. Stray light contamination can be represented by a flat offset in CCD data. Mitigation techniques begin by a comprehensive study during the design phase, followed by the use of target pointing optimisation and post-processing methods. We present a code that aims at simulating the stray-light contamination in low-Earth orbit coming from reflexion of solar light by the Earth. StrAy Light SimulAtor (SALSA) is a tool intended to be used at an early stage as a tool to evaluate the effective visible region in the sky and, therefore to optimise the observation sequence. SALSA can compute Earth stray light contamination for significant periods of time allowing missionwide parameters to be optimised (e.g. impose constraints on the point source transmission function (PST) and/or on the altitude of the satellite). It can also be used to study the behaviour of the stray light at different seasons or latitudes. Given the position of the satellite with respect to the Earth and the Sun, SALSA computes the stray light at the entrance of the telescope following a geometrical technique. After characterising the illuminated region of the Earth, the portion of illuminated Earth that affects the satellite is calculated. Then, the flux of reflected solar photons is evaluated at the entrance of the telescope. Using the PST of the instrument, the final stray light contamination at the detector is calculated. The analysis tools include time series analysis of the contamination, evaluation of the sky coverage and an objects visibility predictor. Effects of the South Atlantic Anomaly and of any shutdown periods of the instrument can be added. Several designs or mission concepts can be easily tested and compared. The code is not thought as a stand-alone mission designer. Its mandatory inputs are a time series describing the trajectory of the satellite and the characteristics of the instrument. This software suite has been applied to the design and analysis of CHEOPS (CHaracterizing ExOPlanet Satellite). This mission requires very high precision photometry to detect very shallow transits of exoplanets. Different altitudes and characteristics of the detector have been studied in order to find the best parameters, that reduce the effect of contamination. © (2014) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
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BACKGROUND Gametogenesis and fertilization play crucial roles in malaria transmission. While male gametes are thought to be amongst the simplest eukaryotic cells and are proven targets of transmission blocking immunity, little is known about their molecular organization. For example, the pathway of energy metabolism that power motility, a feature that facilitates gamete encounter and fertilization, is unknown. METHODS Plasmodium berghei microgametes were purified and analysed by whole-cell proteomic analysis for the first time. Data are available via ProteomeXchange with identifier PXD001163. RESULTS 615 proteins were recovered, they included all male gamete proteins described thus far. Amongst them were the 11 enzymes of the glycolytic pathway. The hexose transporter was localized to the gamete plasma membrane and it was shown that microgamete motility can be suppressed effectively by inhibitors of this transporter and of the glycolytic pathway. CONCLUSIONS This study describes the first whole-cell proteomic analysis of the malaria male gamete. It identifies glycolysis as the likely exclusive source of energy for flagellar beat, and provides new insights in original features of Plasmodium flagellar organization.