Two-dimensional matrix algorithm using detrended fluctuation analysis to distinguish Burkitt and diffuse large B-cell lymphoma

Copyright © 2012 Rong-Guan Yeh et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.A detrended fluctuation analysis (DFA) method is applied to image analysis. The 2-dimensional (2D) DFA algorithms is proposed for recharacterizing images of lymph sections. Due to Burkitt lymphoma (BL) and diffuse large B-cell lymphoma (DLBCL), there is a significant different 5-year survival rates after multiagent chemotherapy. Therefore, distinguishing the difference between BL and DLBCL is very important. In this study, eighteen BL images were classified as group A, which have one to five cytogenetic changes. Ten BL images were classified as group B, which have more than five cytogenetic changes. Both groups A and B BLs are aggressive lymphomas, which grow very fast and require more intensive chemotherapy. Finally, ten DLBCL images were classified as group C. The short-term correlation exponent α1 values of DFA of groups A, B, and C were 0.370 ± 0.033, 0.382 ± 0.022, and 0.435 ± 0.053, respectively. It was found that α1 value of BL image was significantly lower (P < 0.05) than DLBCL. However, there is no difference between the groups A and B BLs. Hence, it can be concluded that α1 value based on DFA statistics concept can clearly distinguish BL and DLBCL image.National Science Council (NSC) of Taiwan the Center for Dynamical Biomarkers and Translational Medicine, National Central University, Taiwan (also sponsored by National Science Council)

Optimizing 4DCBCT Projection Allocation to Respiratory Bins

Four dimensional cone beam computed tomography (4DCBCT) is an emerging image guidance strategy used in radiotherapy where projections acquired during a scan are sorted into respiratory bins based on the respiratory phase or displacement. 4DCBCT reduces the motion blur caused by respiratory motion but increases streaking artefacts due to projection under-sampling as a result of the irregular nature of patient breathing and the binning algorithms used. For displacement binning the streak artefacts are so severe that displacement binning is rarely used clinically. The purpose of this study is to investigate if sharing projections between respiratory bins and adjusting the location of respiratory bins in an optimal manner can reduce or eliminate streak artefacts in 4DCBCT images. We introduce a mathematical optimization framework and a heuristic solution method, which we will call the optimized projection allocation algorithm, to determine where to position the respiratory bins and which projections to source from neighbouring respiratory bins. Five 4DCBCT datasets from three patients were used to reconstruct 4DCBCT images. Projections were sorted into respiratory bins using equispaced, equal density and optimized projection allocation. The standard deviation of the angular separation between projections was used to assess streaking and the consistency of the segmented volume of a ducial gold marker was used to assess motion blur. The standard deviation of the angular separation between projections using displacement binning and optimized projection allocation was 30%-50% smaller than conventional phase based binning and 59%-76% smaller than conventional displacement binning indicating more uniformly spaced projections and fewer streaking artefacts. The standard deviation in the marker volume was 20%-90% smaller when using optimized projection allocation than using conventional phase based binning suggesting more uniform marker segmentation and less motion blur. Images reconstructed using displacement binning and the optimized projection allocation algorithm were clearer, contained visibly fewer streak artefacts and produced more consistent marker segmentation than those reconstructed with either equispaced or equal-density binning. The optimized projection allocation algorithm signi cantly improves image quality in 4DCBCT images and provides, for the rst time, a method to consistently generate high quality displacement binned 4DCBCT images in clinical applications

Self-Weighing in Weight Management Interventions: A Systematic Review of Literature

Background Self-weighing increases a person's self-awareness of current weight and weight patterns. Increased self-weighing frequency can help an individual prevent weight gain. Literature, however, is limited in describing variability in self-weighing strategies and how the variability is associated with weight management outcomes. Aim This review analyzed self-weighing in weight management interventions and the effects of self-weighing on weight and other outcomes. Methods Twenty-two articles from PubMed, CINAHL, Medline, PsychInfo, and Academic Search Premier were extracted for review. Results These 22 articles reported findings from 19 intervention trials, mostly on weight loss or weight gain prevention. The majority of the reviewed articles reported interventions that combined self-weighing with other self-monitoring strategies (64%), adopted daily self-weighing frequency (84%), and implemented interventions up to six months (59%). One-half of the articles mentioned that technology-enhanced or regular weight scales were given to study participants. Of the articles that provided efficacy data, 75% of self-weighing-only interventions and 67% of combined interventions demonstrated improved weight outcomes. No negative psychological effects were found. Conclusions Self-weighing is likely to improve weight outcomes, particularly when performed daily or weekly, without causing untoward adverse effects. Weight management interventions could consider including this strategy

Thermoelastic Damping in Micro- and Nano-Mechanical Systems

The importance of thermoelastic damping as a fundamental dissipation mechanism for small-scale mechanical resonators is evaluated in light of recent efforts to design high-Q micrometer- and nanometer-scale electro-mechanical systems (MEMS and NEMS). The equations of linear thermoelasticity are used to give a simple derivation for thermoelastic damping of small flexural vibrations in thin beams. It is shown that Zener's well-known approximation by a Lorentzian with a single thermal relaxation time slightly deviates from the exact expression.Comment: 10 pages. Submitted to Phys. Rev.

GBM heterogeneity as a function of variable epidermal growth factor receptor variant III activity.

Abnormal activation of the epidermal growth factor receptor (EGFR) due to a deletion of exons 2-7 of EGFR (EGFRvIII) is a common alteration in glioblastoma (GBM). While this alteration can drive gliomagenesis, tumors harboring EGFRvIII are heterogeneous. To investigate the role for EGFRvIII activation in tumor phenotype we used a neural progenitor cell-based murine model of GBM driven by EGFR signaling and generated tumor progenitor cells with high and low EGFRvIII activation, pEGFRHi and pEGFRLo. In vivo, ex vivo, and in vitro studies suggested a direct association between EGFRvIII activity and increased tumor cell proliferation, decreased tumor cell adhesion to the extracellular matrix, and altered progenitor cell phenotype. Time-lapse confocal imaging of tumor cells in brain slice cultures demonstrated blood vessel co-option by tumor cells and highlighted differences in invasive pattern. Inhibition of EGFR signaling in pEGFRHi promoted cell differentiation and increased cell-matrix adhesion. Conversely, increased EGFRvIII activation in pEGFRLo reduced cell-matrix adhesion. Our study using a murine model for GBM driven by a single genetic driver, suggests differences in EGFR activation contribute to tumor heterogeneity and aggressiveness

Respiratory Motion Guided Four Dimensional Cone Beam Computed Tomography: Encompassing Irregular Breathing

Four dimensional cone beam computed tomography (4DCBCT) images su er from angular under sampling and bunching of projections due to a lack of feedback between the respiratory signal and the acquisition system. To address this problem, Respiratory Motion Guided 4DCBCT (RMG-4DCBCT) regulates the gantry velocity and projection time interval, in response to the patient's respiratory signal, with the aim of acquiring evenly spaced projections in a number of phase or displacement bins during the respiratory cycle. Our previous study of RMG- 4DCBCT was limited to sinusoidal breathing traces. Here we expand on that work to provide a practical algorithm for the case of real patient breathing data. We give a complete description of RMG-4DCBCT including full details on how to implement the algorithms to determine when to move the gantry and when to acquire projections in response to the patient's respiratory signal. We simulate a realistic working RMG-4DCBCT system using 112 breathing traces from 24 lung cancer patients. Acquisition used phase-based binning and parameter settings typically used on commercial 4DCBCT systems (4 minute acquisition time, 1200 projections across 10 respiratory bins), with the acceleration and velocity constraints of current generation linear accelerators. We quanti ed streaking artefacts and image noise for conventional and RMG-4DCBCT methods by reconstructing projection data selected from an oversampled set of Catphan phantom projections. RMG-4DCBCT allows us to optimally trade-o image quality, acquisition time and image dose. For example, for the same image quality and acquisition time as conventional 4DCBCT approximately half the imaging dose is needed. Alternatively, for the same imaging dose, the image quality as measured by the signal to noise ratio, is improved by 63% on average. C- arm CBCT systems, with an acceleration up to 200 degrees=s2, a velocity up to 100 degrees=s and the acquisition of 80 projections per second, allow the image acquisition time to be reduced to below 60 seconds. We have made considerable progress towards realising a system to reduce projection clustering in conventional 4DCBCT imaging and hence reduce the imaging dose to the patient

Fatal encephalitis and myocarditis in young domestic geese (Anser anser domesticus) caused by West Nile virus.

During 1999 and 2000, a disease outbreak of West Nile (WN) virus occurred in humans, horses, and wild and zoological birds in the northeastern USA. In our experiments, WN virus infection of young domestic geese (Anser anser domesticus) caused depression, weight loss, torticollis, opisthotonus, and death with accompanying encephalitis and myocarditis. Based on this experimental study and a field outbreak in Israel, WN virus is a disease threat to young goslings and viremia levels are potentially sufficient to infect mosquitoes and transmit WN virus to other animal species

Measurement of gut permeability using fluorescent tracer agent technology

Abstract The healthy gut restricts macromolecular and bacterial movement across tight junctions, while increased intestinal permeability accompanies many intestinal disorders. Dual sugar absorption tests, which measure intestinal permeability in humans, present challenges. Therefore, we asked if enterally administered fluorescent tracers could ascertain mucosal integrity, because transcutaneous measurement of differentially absorbed molecules could enable specimen-free evaluation of permeability. We induced small bowel injury in rats using high- (15 mg/kg), intermediate- (10 mg/kg), and low- (5 mg/kg) dose indomethacin. Then, we compared urinary ratios of enterally administered fluorescent tracers MB-402 and MB-301 to urinary ratios of sugar tracers lactulose and rhamnose. We also tested the ability of transcutaneous sensors to measure the ratios of absorbed fluorophores. Urinary fluorophore and sugar ratios reflect gut injury in an indomethacin dose dependent manner. The fluorophores generated smooth curvilinear ratio trajectories with wide dynamic ranges. The more chaotic sugar ratios had narrower dynamic ranges. Fluorophore ratios measured through the skin distinguished indomethacin-challenged from same day control rats. Enterally administered fluorophores can identify intestinal injury in a rat model. Fluorophore ratios are measureable through the skin, obviating drawbacks of dual sugar absorption tests. Pending validation, this technology should be considered for human use