905 resultados para Negative dimensional integration method (NDIM)


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Aus dem tumorreaktiven T-Zellrepertoire der Melanompatientin Ma-Mel-86/INTH, bei der im Verlauf Lymphknotenmetastasen HLA-Klasse I-negativer Tumorzellen auftraten, wurden durch Stimulation mit autologen Tumorzellen CD8+ T-Zellklone isoliert und expandiert, die auf Melanomzellen der Patientin CSF2RA (engl. GM-CSF receptor alpha chain) in HLA-unabhängiger Weise erkannten. Aus einem der T-Zellklone wurde ein CSF2RA-reaktiver α:β-T-Zellrezeptor (TCR, engl. T-cell receptor) kloniert (Bezeichnung: TCR-1A.3/46). Die α-Kette des TCR enthielt die Domänen TRAV14/DV4*01, TRAJ48*01 und TRAC*01, die β-Kette die Domänen TRBV10-3*01, TRBD2*01, TRBJ2-7*01 und TRBC2*01. Durch Austausch der humanen konstanten gegen die homologen murinen Domänen wurde der TCR optimiert (Bezeichnung: cTCR-1A.3/46) und hinsichtlich seiner Expression und Funktionalität nach retroviralem Transfer in humane PBMC (engl. peripheral blood mononuclear cells) im 51Chromfreisetzungstest, im IFN-γ-ELISpot-Assay und in einem Degranulations-Assay validiert. TCR-transgene T-Zellen lysierten nicht nur spezifisch die HLA-defizienten, CSF2RA+ Melanomlinien des Modells Ma-Mel-86, sondern erkannten auch Zelllinien verschiedener Spezies nach Transfektion von CSF2RA sowie Monozyten, Granulozyten, dendritische Zellen und ein breites Spektrum hämatologischer Malignome myeloiden Ursprungs ungeachtet deren HLA-Phänotypen. Lymphatische Zellen sowie CD34+ Blutstammzellen wurden in In vitro-Untersuchungen nicht erkannt. Der Zusatz von GM-CSF zu Zellen, die CSF2RA und CSF2RB exprimierten, inhibierte die Erkennung durch TCR-transgene PBMC, während die Koexpression der α- und der ß-Kette des GM-CSF-Rezeptors alleine keinen negativen Effekt auf die Erkennung hatte. Daraus war zu schließen, dass CSF2RA präferentiell freistehend und weniger nach Integration in den heteromultimerischen GM-CSF-Rezeptor-Komplex erkannt wurde. In der zweidimensionalen Collier-de-Perles-Visualisierung der IMGT-Datenbank (engl. International immunogenetics information system) wies der CSF2RA-reaktive TCR-1A.3/46 im Vergleich zu TCR von konventionellen, HLA-restringierten T-Zellen keine Besonderheiten auf. Darüber hinaus waren auch die von den HLA-unabhängigen T-Zellen exprimierten CD8-Moleküle identisch zu den CD8-Molekülen HLA-abhängiger CTL (engl. cytotoxic T lymphocytes). Die Präsenz von CD8-Molekülen förderte die HLA-unabhängige Erkennung von CSF2RA, schien aber dafür nicht zwingend erforderlich zu sein, da Antikörper gegen CD8 die Erkennung zu ca. 65 % blockierten und TCR-transgene CD4+ T-Zellen im Vergleich zu TCR-transduzierten CD8+ T-Zellen eine deutlich verringerte, aber noch erhaltene Funktionalität aufwiesen. Es ist derzeit nicht klar, ob HLA-unabhängige T-Zellen gegen CSF2RA im peripheren Blut der Patientin vorkamen, weil sie der im Tiermodell postulierten Thymusselektion MHC-unabhängiger TCR (Tikhonova et al., Immunity 36:79, 2012) entkommen waren, oder weil ein ursprünglich gegen einen HLA-Peptid-Komplex gerichteter TCR eine HLA-unabhängige Kreuzreaktivität aufwies. CSF2RA verbessert die Glucoseutilisation in malignen Zellen, und es wurden ihm embryotrophe Eigenschaften zugeschrieben (Spielholz et al., Blood 85:973, 1995; Sjöblom et al., Biol. Reprod. 67:1817, 2002). Damit kann CSF2RA malignes Wachstum fördern und ist somit ein potentielles Zielmolekül für die Immuntherapie. Seine HLA-unabhängige Erkennung würde sowohl die HLA-Vielfalt als auch den HLA-Verlust als typische Limitationen der T-Zellimmuntherapie umgehen. Zur Überprüfung der In vivo-Spezifität des HLA-unabhängigen TCR gegen CSF2RA und damit zum Ausschluss relevanter off-tumor-/on-target- bzw. off-tumor-/off-target-Effekte ist jedoch eine Testung in einem präklinischen Tiermodell erforderlich.

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Osteoarticular allograft is one possible treatment in wide surgical resections with large defects. Performing best osteoarticular allograft selection is of great relevance for optimal exploitation of the bone databank, good surgery outcome and patient’s recovery. Current approaches are, however, very time consuming hindering these points in practice. We present a validation study of a software able to perform automatic bone measurements used to automatically assess the distal femur sizes across a databank. 170 distal femur surfaces were reconstructed from CT data and measured manually using a size measure protocol taking into account the transepicondyler distance (A), anterior-posterior distance in medial condyle (B) and anterior-posterior distance in lateral condyle (C). Intra- and inter-observer studies were conducted and regarded as ground truth measurements. Manual and automatic measures were compared. For the automatic measurements, the correlation coefficients between observer one and automatic method, were of 0.99 for A measure and 0.96 for B and C measures. The average time needed to perform the measurements was of 16 h for both manual measurements, and of 3 min for the automatic method. Results demonstrate the high reliability and, most importantly, high repeatability of the proposed approach, and considerable speed-up on the planning.

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A new simple method for two-dimensional determination of optical density of macular pigment xanthophyll (ODx) in clinical routine is based on a single blue-reflection fundus image. Individual different vignetting is corrected by a shading function. For its construction, nodes are automatically found in structureless image regions. The influence of stray light in elderly crystalline lenses is compensated by a correction function that depends on age. The reproducibility of parameters in a one-wavelength reflection method determined for three subjects (47, 61, and 78 years old) was: maxODx = 6.3%, meanODx = 4.6%, volume = 6%, and area = 6% already before stray-light correction. ODx was comparable in pseudophakic and in an eye with a crystalline lens of the same 11 subjects after stray-light correction. Significant correlation in ODx was found between the one-wavelength reflection method and the two-wavelength autofluorescence method for pseudophakic and cataract eyes of 19 patients suffering from dry age-related macular degeneration (AMD) (R(2) = 0.855). In pseudophakic eyes, maxODx was significantly lower for dry AMD (n = 45) (ODx = 0.491±0.102 ODU) than in eyes with healthy fundus (n = 22) (ODx = 0.615±0.103 ODU) (p = 0.000033). Also in eyes with crystalline lens, maxODx was lower in AMD (n = 125) (ODx = 0.610±0.093 ODU) than in healthy subjects (n = 45) (ODx = 0.674±0.098 ODU) (p = 0.00019). No dependence on age was found in the pseudophakic eyes both of healthy subjects and AMD patients.

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In schizophrenia, nonverbal behavior, including body movement, is of theoretical and clinical importance. Although reduced nonverbal expressiveness is a major component of the negative symptoms encountered in schizophrenia, few studies have objectively assessed body movement during social interaction. In the present study, 378 brief, videotaped role-play scenes involving 27 stabilized outpatients diagnosed with paranoid-type schizophrenia were analyzed using Motion Energy Analysis (MEA). This method enables the objective measuring of body movement in conjunction with ordinary video recordings. Correlations between movement parameters (percentage of time in movement, movement speed) and symptom ratings from independent PANSS interviews were calculated. Movement parameters proved to be highly reliable. In keeping with predictions, reduced movement and movement speed correlated with negative symptoms. Accordingly, in patients who exhibited noticeable movement for less than 20% of the observation time, prominent negative symptoms were highly probable. As a control measure, the percentage of movement exhibited by the patients during role-play scenes was compared to that of their normal interactants. Patients with negative symptoms differed from normal interactants by showing significantly reduced head and body movement. Two specific positive symptoms were possibly related to movement parameters: suspiciousness tended to correlate with reduced head movement, and the expression of unusual thought content tended to relate to increased movement. Overall, a close and theoretically meaningful association between the objective movement parameters and the symptom profiles was found. MEA appears to be an objective, reliable and valid method for quantifying nonverbal behavior, an aspect which may furnish new insights into the processes related to reduced expressiveness in schizophrenia.

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Mechanical ventilation is not only a life saving treatment but can also cause negative side effects. One of the main complications is inflammation caused by overstretching of the alveolar tissue. Previously, studies investigated either global strains or looked into which states lead to inflammatory reactions in cell cultures. However, the connection between the global deformation, of a tissue strip or the whole organ, and the strains reaching the single cells lining the alveolar walls is unknown and respective studies are still missing. The main reason for this is most likely the complex, sponge-like alveolar geometry, whose three-dimensional details have been unknown until recently. Utilizing synchrotron-based X-ray tomographic microscopy, we were able to generate real and detailed three-dimensional alveolar geometries on which we have performed finite-element simulations. This allowed us to determine, for the first time, a three-dimensional strain state within the alveolar wall. Briefly, precision-cut lung slices, prepared from isolated rat lungs, were scanned and segmented to provide a three-dimensional geometry. This was then discretized using newly developed tetrahedral elements. The main conclusions of this study are that the local strain in the alveolar wall can reach a multiple of the value of the global strain, for our simulations up to four times as high and that thin structures obviously cause hotspots that are especially at risk of overstretching.

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A liquid chromatography tandem mass spectrometry (LC-MS/MS) confirmatory method for the simultaneous determination of nine corticosteroids in liver, including the four MRL compounds listed in Council Regulation 37/2010, was developed. After an enzymatic deconjugation and a solvent extraction of the liver tissue, the resulting solution was cleaned up through an SPE Oasis HLB cartridge. The analytes were then detected by liquid chromatography-negative-ion electrospray tandem mass spectrometry, using deuterium-labelled internal standards. The procedure was validated as a quantitative confirmatory method according to the Commission Decision 2002/657/EC criteria. The results showed that the method was suitable for statutory residue testing regarding the following performance characteristics: instrumental linearity, specificity, precision (repeatability and intra-laboratory reproducibility), recovery, decision limit (CCα), detection capability (CCβ) and ruggedness. All the corticosteroids can be detected at a concentration around 1 μg kg(-1); the recoveries were above 62% for all the analytes. Repeatability and reproducibility (within-laboratory reproducibility) for all the analytes were below 7.65% and 15.5%, respectively.

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BACKGROUND: The objective of this study was to link expression patterns of B-cell-specific Moloney murine leukemia virus integration site 1 (Bmi-1) and p16 to patient outcome (recurrence and survival) in a cohort of 252 patients with oral and oropharyngeal squamous cell cancer (OSCC). METHODS: Expression levels of Bmi-1 and p16 in samples from 252 patients with OSCC were evaluated immunohistochemically using the tissue microarray method. Staining intensity was determined by calculating an intensity reactivity score (IRS). Staining intensity and the localization of expression within tumor cells (nuclear or cytoplasmic) were correlated with overall, disease-specific, and recurrence-free survival. RESULTS: The majority of cancers were localized in the oropharynx (61.1%). In univariate analysis, patients who had OSCC and strong Bmi-1 expression (IRS >10) had worse outcomes compared with patients who had low and moderate Bmi-1 expression (P = .008; hazard ratio [HR], 1.82; 95% confidence interval [CI], 1.167-2.838); this correlation was also observed for atypical cytoplasmic Bmi-1 expression (P = .001; HR, 2.164; 95% CI, 1.389-3.371) and for negative p16 expression (P < .001; HR, 0.292; 95% CI, 0.178-0.477). The combination of both markers, as anticipated, had an even stronger correlation with overall survival (P < .001; HR, 8.485; 95% CI, 4.237-16.994). Multivariate analysis demonstrated significant results for patients with oropharyngeal cancers, but not for patients with oral cavity tumors: Tumor classification (P = .011; HR, 1.838; 95%CI, 1.146-2.947) and the combined marker expression patterns (P < .001; HR, 6.254; 95% CI, 2.869-13.635) were correlated with overall survival, disease-specific survival (tumor classification: P = .002; HR, 2.807; 95% CI, 1.477-5.334; combined markers: P = .002; HR, 5.386; 95% CI, 1.850-15.679), and the combined markers also were correlated with recurrence-free survival (P = .001; HR, 8.943; 95% CI, 2.562-31.220). CONCLUSIONS: Cytoplasmic Bmi-1 expression, an absence of p16 expression, and especially the combination of those 2 predictive markers were correlated negatively with disease-specific and recurrence-free survival in patients with oropharyngeal cancer. Therefore, the current results indicate that these may be applicable as predictive markers in combination with other factors to select patients for more aggressive treatment and follow-up. Cancer 2011;. © 2011 American Cancer Society.

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Gamma zero-lag phase synchronization has been measured in the animal brain during visual binding. Human scalp EEG studies used a phase locking factor (trial-to-trial phase-shift consistency) or gamma amplitude to measure binding but did not analyze common-phase signals so far. This study introduces a method to identify networks oscillating with near zero-lag phase synchronization in human subjects.

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Three comprehensive one-dimensional simulators were used on the same PC to simulate the dynamics of different electrophoretic configurations, including two migrating hybrid boundaries, an isotachophoretic boundary and the zone electrophoretic separation of ten monovalent anions. Two simulators, SIMUL5 and GENTRANS, use a uniform grid, while SPRESSO uses a dynamic adaptive grid. The simulators differ in the way components are handled. SIMUL5 and SPRESSO feature one equation for all components, whereas GENTRANS is based on the use of separate modules for the different types of monovalent components, a module for multivalent components and a module for proteins. The code for multivalent components is executed more slowly compared to those for monovalent components. Furthermore, with SIMUL5, the computational time interval becomes smaller when it is operated with a reduced calculation space that features moving borders, whereas GENTRANS offers the possibility of using data smoothing (removal of negative concentrations), which can avoid numerical oscillations and speed up a simulation. SPRESSO with its adaptive grid could be employed to simulate the same configurations with smaller numbers of grid points and thus is faster in certain but not all cases. The data reveal that simulations featuring a large number of monovalent components distributed such that a high mesh is required throughout a large proportion of the column are fastest executed with GENTRANS.

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Cranioplasty is a common neurosurgical procedure. Free-hand molding of polymethyl methacrylate (PMMA) cement into complex three-dimensional shapes is often time-consuming and may result in disappointing cosmetic outcomes. Computer-assisted patient-specific implants address these disadvantages but are associated with long production times and high costs. In this study, we evaluated the clinical, radiological, and cosmetic outcomes of a time-saving and inexpensive intraoperative method to mold custom-made implants for immediate single-stage or delayed cranioplasty. Data were collected from patients in whom cranioplasty became necessary after removal of bone flaps affected by intracranial infection, tumor invasion, or trauma. A PMMA replica was cast between a negative form of the patient's own bone flap and the original bone flap with exactly the same shape, thickness, and dimensions. Clinical and radiological follow-up was performed 2 months post-surgery. Patient satisfaction (Odom criteria) and cosmesis (visual analogue scale for cosmesis) were evaluated 1 to 3 years after cranioplasty. Twenty-seven patients underwent intraoperative template-molded patient-specific cranioplasty with PMMA. The indications for cranioplasty included bone flap infection (56%, n = 15), calvarian tumor resection (37%, n = 10), and defect after trauma (7%, n = 2). The mean duration of the molding procedure was 19 ± 7 min. Excellent radiological implant alignment was achieved in 94% of the cases. All (n = 23) but one patient rated the cosmetic outcome (mean 1.4 years after cranioplasty) as excellent (70%, n = 16) or good (26%, n = 6). Intraoperative cast-molded reconstructive cranioplasty is a feasible, accurate, fast, and cost-efficient technique that results in excellent cosmetic outcomes, even with large and complex skull defects.

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A main field in biomedical optics research is diffuse optical tomography, where intensity variations of the transmitted light traversing through tissue are detected. Mathematical models and reconstruction algorithms based on finite element methods and Monte Carlo simulations describe the light transport inside the tissue and determine differences in absorption and scattering coefficients. Precise knowledge of the sample's surface shape and orientation is required to provide boundary conditions for these techniques. We propose an integrated method based on structured light three-dimensional (3-D) scanning that provides detailed surface information of the object, which is usable for volume mesh creation and allows the normalization of the intensity dispersion between surface and camera. The experimental setup is complemented by polarization difference imaging to avoid overlaying byproducts caused by inter-reflections and multiple scattering in semitransparent tissue.

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Dimensional modeling, GT-Power in particular, has been used for two related purposes-to quantify and understand the inaccuracies of transient engine flow estimates that cause transient smoke spikes and to improve empirical models of opacity or particulate matter used for engine calibration. It has been proposed by dimensional modeling that exhaust gas recirculation flow rate was significantly underestimated and volumetric efficiency was overestimated by the electronic control module during the turbocharger lag period of an electronically controlled heavy duty diesel engine. Factoring in cylinder-to-cylinder variation, it has been shown that the electronic control module estimated fuel-Oxygen ratio was lower than actual by up to 35% during the turbocharger lag period but within 2% of actual elsewhere, thus hindering fuel-Oxygen ratio limit-based smoke control. The dimensional modeling of transient flow was enabled with a new method of simulating transient data in which the manifold pressures and exhaust gas recirculation system flow resistance, characterized as a function of exhaust gas recirculation valve position at each measured transient data point, were replicated by quasi-static or transient simulation to predict engine flows. Dimensional modeling was also used to transform the engine operating parameter model input space to a more fundamental lower dimensional space so that a nearest neighbor approach could be used to predict smoke emissions. This new approach, intended for engine calibration and control modeling, was termed the "nonparametric reduced dimensionality" approach. It was used to predict federal test procedure cumulative particulate matter within 7% of measured value, based solely on steady-state training data. Very little correlation between the model inputs in the transformed space was observed as compared to the engine operating parameter space. This more uniform, smaller, shrunken model input space might explain how the nonparametric reduced dimensionality approach model could successfully predict federal test procedure emissions when roughly 40% of all transient points were classified as outliers as per the steady-state training data.

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Model-based calibration of steady-state engine operation is commonly performed with highly parameterized empirical models that are accurate but not very robust, particularly when predicting highly nonlinear responses such as diesel smoke emissions. To address this problem, and to boost the accuracy of more robust non-parametric methods to the same level, GT-Power was used to transform the empirical model input space into multiple input spaces that simplified the input-output relationship and improved the accuracy and robustness of smoke predictions made by three commonly used empirical modeling methods: Multivariate Regression, Neural Networks and the k-Nearest Neighbor method. The availability of multiple input spaces allowed the development of two committee techniques: a 'Simple Committee' technique that used averaged predictions from a set of 10 pre-selected input spaces chosen by the training data and the "Minimum Variance Committee" technique where the input spaces for each prediction were chosen on the basis of disagreement between the three modeling methods. This latter technique equalized the performance of the three modeling methods. The successively increasing improvements resulting from the use of a single best transformed input space (Best Combination Technique), Simple Committee Technique and Minimum Variance Committee Technique were verified with hypothesis testing. The transformed input spaces were also shown to improve outlier detection and to improve k-Nearest Neighbor performance when predicting dynamic emissions with steady-state training data. An unexpected finding was that the benefits of input space transformation were unaffected by changes in the hardware or the calibration of the underlying GT-Power model.

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Background Although individuals vulnerable to psychosis show brain volumetric abnormalities, structural alterations underlying different probabilities for later transition are unknown. The present study addresses this issue by means of voxel-based morphometry (VBM). Method We investigated grey matter volume (GMV) abnormalities by comparing four neuroleptic-free groups: individuals with first episode of psychosis (FEP) and with at-risk mental state (ARMS), with either long-term (ARMS-LT) or short-term ARMS (ARMS-ST), compared to the healthy control (HC) group. Using three-dimensional (3D) magnetic resonance imaging (MRI), we examined 16 FEP, 31 ARMS, clinically followed up for on average 3 months (ARMS-ST, n=18) and 4.5 years (ARMS-LT, n=13), and 19 HC. Results The ARMS-ST group showed less GMV in the right and left insula compared to the ARMS-LT (Cohen's d 1.67) and FEP groups (Cohen's d 1.81) respectively. These GMV differences were correlated positively with global functioning in the whole ARMS group. Insular alterations were associated with negative symptomatology in the whole ARMS group, and also with hallucinations in the ARMS-ST and ARMS-LT subgroups. We found a significant effect of previous antipsychotic medication use on GMV abnormalities in the FEP group. Conclusions GMV abnormalities in subjects at high clinical risk for psychosis are associated with negative and positive psychotic symptoms, and global functioning. Alterations in the right insula are associated with a higher risk for transition to psychosis, and thus may be related to different transition probabilities.

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The socialisation of mentally handicapped people is a long-term process during which the disabled person learns new habits and abilities step by step through education and training. Anxiety and neuroses due to an inadequate social environment can place obstacles in the path of the disabled person's integration into society. A method of regulating the psycho-physiological condition of mentally handicapped people (MRPC) was developed in order to reduce anxiety and neuropsychological tension and to establish positive social attitudes. Both verbal and non-verbal means of manipulating the psycho-physiological condition were used and experimental and control groups were formed from among the clients of Israelian's institute. The experimental groups applied the new method for six months, leading to a significant shift in the response of the clients involved. Expressed anxiety and defensive responses to mental tasks were transformed into orienting responses after 30 psycho-regulative exercises. Cognitive functions such as attention and memory also improved significantly. EEG examinations of the actual process of psycho-regulation revealed a tendency towards a change of brain activity by increasing the fast pulse frequency values in the alpha zones. Israelian concludes that the application of the MRPC creates better functional conditions for the socialisation of mentally handicapped people.