bluuebunny/crossref_metadata_2025_split huggingface dataset:
Disease‐associated polymorphisms in 9p21 are not associated with extreme longevity
Authors: Congrains Ada , Kamide Kei , Hirose Nobuyoshi , Arai Yasumichi , Oguro Ryousuke , Nakama Chikako , Imaizumi Yuki , Kawai Tatsuo , Kusunoki Hiroshi , Yamamoto Hiroko , Onishi‐Takeya Miyuki , Takeya Yasushi , Yamamoto Koichi , Sugimoto Ken , Akasaka Hiroshi , Saitoh Shigeyuki , Miura Tetsuji , Awata Nobuhisa , Kato Norihiro , Katsuya Tomohiro , Ikebe Kazunori , Gondo Yasuyuki , Rakugi Hiromi 
Published: September 2014

AimThe 9p21 region has been pointed out by the genome‐wide association studies as a hot spot for disease‐associated variants. Most of the diseases linked with the locus are aging‐related conditions, such us cardiovascular disease, diabetes and cancer. Centenarians are known to present a reduced risk and delayed onset for these conditions. Here, we aimed to assess if the 9p21 variants contribute to this protection by possibly altering basic aging mechanisms.MethodsWe genotyped 15 tag single‐nucleotide polymorphisms (SNP) along the CDKN2A/B/ANRIL locus in 1505 individuals. The participants were divided in three groups: centenarians, septuagenarians and young controls. Centenarians were 593 participants (age range 100–116 years, mean 105.9 years), septuagenarians were 434 volunteers aged between 69 and 71 years (mean 70.1 ± 0.9 years) and the 478 young controls were under the age of 50 years (range 14–50 years, mean 41.8 years). We genotyped the SNP rs1333049 in an additional sample of 231 coronary artery disease patients to confirm the 9p21 association.ResultsThe leading coronary artery disease‐associated SNP rs1333049 was associated with coronary artery disease; however, none of the 9p21 SNP evaluated in the present study were associated with extreme longevity.ConclusionsOur findings suggest that the 9p21 disease‐associated polymorphisms do not contribute to the life‐long protection from cardiovascular and other age‐related diseases observed in centenarians. It is likely that this protection is mediated by mechanisms different from the ones underlying the 9p21 association. Geriatr Gerontol Int 2015; 15: 797–803.
Hospital admissions after transrectal ultrasound‐guided biopsy of the prostate in men diagnosed with prostate cancer: A database analysis in England
Authors: Anastasiadis Eleni , van der Meulen Jan , Emberton Mark 
Published: September 2014

ObjectivesTo investigate the complication rate within 30 days after transrectal ultrasound‐guided biopsy of the prostate in England, and to examine associated risk factors.MethodsA population‐based study was carried out using the English cancer registry linked to administrative hospital data. We included men aged 45 years and older diagnosed with prostate cancer between 2000 and 2008. A complication was considered to have occurred if men had been admitted to hospital as a result of urological causes (urinary tract infection/sepsis, hematuria and urinary retention) within 30 days of the transrectal ultrasound‐guided biopsy of the prostate. Multivariable logistic regression was carried out to estimate odds ratios, reflecting the impact of risk factors on the complication rate.ResultsOf the 198 361 included men, 69% were aged between 65 and 84 years. The 30‐day complication rate was 3.7% (1.1% for urinary tract infection/sepsis, 1.4% for hematuria and 1.3% for urinary retention). The most important risk factors were age above 85 years (odds ratio 3.85, 95% confidence interval 3.18–4.67, compared with age below 55 years) and three or more comorbidities (odds ratio 3.50, 95% confidence interval 3.17–5.87, compared with no comorbidity). The overall complication rate increased over time (odds ratio 1.20, 95% confidence interval 1.08–1.34, 2008 compared with 2000), as did the complication rate as a result of urinary tract infection/sepsis (odds ratio 1.72, 95% confidence interval 1.41–2.10, 2008 compared with 2000).ConclusionsThere has been an increase in the complication rate after transrectal ultrasound‐guided biopsy of the prostate in England between 2000 and 2008, predominantly as a result of infections. Age and comorbid conditions seem to represent the two most important risk factors for occurrence of post‐biopsy complications.
A large candidate‐gene association study suggests genetic variants at IRF5 and PRDM1 to be associated with aggressive periodontitis
Authors: Schaefer Arne S. , Jochens Arne , Dommisch Henrik , Graetz Christian , Jockel‐Schneider Yvonne , Harks Inga , Staufenbiel Ingmar , Meyle Joerg , Eickholz Peter , Folwaczny Mathias , Laine Marja , Noack Barbara , Wijmenga Cisca , Lieb Wolfgang , Bruckmann Corinna , Schreiber Stefan , Jepsen Søren , Loos Bruno G. 
Published: September 2014

AbstractAimEpidemiological and clinical studies indicated a relationship of periodontitis with rheumatoid arthritis (RA). We aimed to identify shared genetic susceptibility loci of RA and periodontitis.Materials and MethodsForty‐seven risk genes of genome‐wide significance of RA and SLE were genotyped in a German case–control sample of aggressive periodontitis (AgP), using Immunochip genotyping arrays (Illumina, 600 cases, 1440 controls) and Affymetrix 500 K Genotyping Arrays (280 cases and 983 controls). Significant associations were replicated in 168 Dutch AgP cases and 679 controls and adjusted for the confounders smoking and sex.ResultsVariants at IRF5 and PRDM1 showed association with AgP. Upon covariate adjustment for smoking and sex, the most strongly associated variant at IRF5 was the rare variant rs62481981 (ppooled = 0.0012, odds ratio [OR] = 3.1, 95% confidence interval [95% CI] = 1.6–6.1; 801 cases, 1476 controls).Within PRDM1 it was rs6923419 (ppooled = 0.004, OR = 0.7, 95% CI = 0.6–0.9; 833 cases, 1440 controls). The associations lost significance after correction for multiple testing in the replication. Both genes are implicated in beta‐interferon signalling and are also genome‐wide associated with SLE and inflammatory bowel disease.ConclusionThe study gives no definite evidence for a pathogenic genetic link of periodontitis and RA but suggests IRF5 and PRDM1 as shared susceptibility factors.
Working memory and cognitive flexibility‐training for children with an autism spectrum disorder: a randomized controlled trial
Authors: de Vries Marieke , Prins Pier J.M. , Schmand Ben A. , Geurts Hilde M. 
Published: September 2014

BackgroundPeople with autism spectrum disorders (ASDs) experience executive function (EF) deficits. There is an urgent need for effective interventions, but in spite of the increasing research focus on computerized cognitive training, this has not been studied in ASD. Hence, we investigated two EF training conditions in children with ASD.MethodsIn a randomized controlled trial, children with ASD (n = 121, 8–12 years, IQ > 80) were randomly assigned to an adaptive working memory (WM) training, an adaptive cognitive flexibility‐training, or a non‐adaptive control training (mock‐training). Braingame Brian, a computerized EF‐training with game‐elements, was used. Outcome measures (pretraining, post‐training, and 6‐week‐follow‐up) were near‐transfer to trained EFs, far‐transfer to other EFs (sustained attention and inhibition), and parent's ratings of daily life EFs, social behavior, attention deficit hyperactivity disorder (ADHD)‐behavior, and quality of life.ResultsAttrition‐rate was 26%. Children in all conditions who completed the training improved in WM, cognitive flexibility, attention, and on parent's ratings, but not in inhibition. There were no significant differential intervention effects, although children in the WM condition showed a trend toward improvement on near‐transfer WM and ADHD‐behavior, and children in the cognitive flexibility condition showed a trend toward improvement on near‐transfer flexibility.ConclusionAlthough children in the WM condition tended to improve more in WM and ADHD‐behavior, the lack of differential improvement on most outcome measures, the absence of a clear effect of the adaptive training compared to the mock‐training, and the high attrition rate suggest that the training in its present form is probably not suitable for children with ASD.
Personality and Behavior in Social Dilemmas: Testing the Situational Strength Hypothesis and the Role of Hypothetical Versus Real Incentives
Authors: Lozano José H. 
Published: September 2014

AbstractPrevious research aimed at testing the situational strength hypothesis suffers from serious limitations regarding the conceptualization of strength. In order to overcome these limitations, the present study attempts to test the situational strength hypothesis based on the operationalization of strength as reinforcement contingencies. One dispositional factor of proven effect on cooperative behavior, social value orientation (SVO), was used as a predictor of behavior in four social dilemmas with varying degree of situational strength. The moderating role of incentive condition (hypothetical vs. real) on the relationship between SVO and behavior was also tested. One hundred undergraduates were presented with the four social dilemmas and the Social Value Orientation Scale. One‐half of the sample played the social dilemmas using real incentives, whereas the other half used hypothetical incentives. Results supported the situational strength hypothesis in that no behavioral variability and no effect of SVO on behavior were found in the strongest situation. However, situational strength did not moderate the effect of SVO on behavior in situations where behavior showed variability. No moderating effect was found for incentive condition either. The implications of these results for personality theory and assessment are discussed.
ADP‐ribosylation factor 6 acts as an allosteric activator for the folded but not disordered cholera toxin A1 polypeptide
Authors: Banerjee Tuhina , Taylor Michael , Jobling Michael G. , Burress Helen , Yang ZhiJie , Serrano Albert , Holmes Randall K. , Tatulian Suren A. , Teter Ken 
Published: September 2014

SummaryThe catalytic A1 subunit of cholera toxin (CTA1) has a disordered structure at 37°C. An interaction with host factors must therefore place CTA1 in a folded conformation for the modification of its Gsα target which resides in a lipid raft environment. Host ADP‐ribosylation factors (ARFs) act as in vitro allosteric activators of CTA1, but the molecular events of this process are not fully characterized. Isotope‐edited Fourier transform infrared spectroscopy monitored ARF6‐induced structural changes to CTA1, which were correlated to changes in CTA1 activity. We found ARF6 prevents the thermal disordering of structured CTA1 and stimulates the activity of stabilized CTA1 over a range of temperatures. Yet ARF6 alone did not promote the refolding of disordered CTA1 to an active state. Instead, lipid rafts shifted disordered CTA1 to a folded conformation with a basal level of activity that could be further stimulated by ARF6. Thus, ARF alone is unable to activate disordered CTA1 at physiological temperature: additional host factors such as lipid rafts place CTA1 in the folded conformation required for its ARF‐mediated activation. Interaction with ARF is required for in vivo toxin activity, as enzymatically active CTA1 mutants that cannot be further stimulated by ARF6 fail to intoxicate cultured cells.
Paper oil and physical oil: has speculative pressure in oil futures increased volatility in spot oil prices?
Authors: Fowowe Babajide 
Published: September 2014

AbstractA number of authors have attributed the high and volatile oil prices experienced since the turn of the 21st century to increased speculative activities arising from a relaxation of regulations in futures markets. This study examined the effects of speculative pressure on the volatility of spot oil prices. I constructed two measures of speculative pressure and modelled the volatility in oil returns by using the GARCH autoregressive conditional jump intensity model of Chan and Maheu, which models the effects of extreme news events in returns. Empirical results showed a significant positive coefficient for speculative pressure, implying that increased speculative pressure has contributed to volatile oil prices. This result is robust to different GARCH estimators and measures of speculative pressure.
Sci—Thur AM: YIS ‐ 03: irtGPUMCD: a new GPU‐calculated dosimetry code for 177Lu‐octreotate radionuclide therapy of neuroendocrine tumors
Authors: Montégiani Jean‐François , Gaudin Émilie , Jackson Price A. , Beauregard Jean‐Mathieu , Després Philippe 
Published: September 2014

In peptide receptor radionuclide therapy (PRRT), huge inter‐patient variability in absorbed radiation doses per administered activity mandates the utilization of individualized dosimetry to evaluate therapeutic efficacy and toxicity. We created a reliable GPU‐calculated dosimetry code (irtGPUMCD) and assessed 177Lu‐octreotate renal dosimetry in eight patients (4 cycles of approximately 7.4 GBq).irtGPUMCD was derived from a brachytherapy dosimetry code (bGPUMCD), which was adapted to 177Lu PRRT dosimetry. Serial quantitative single‐photon emission computed tomography (SPECT) images were obtained from three SPECT/CT acquisitions performed at 4, 24 and 72 hours after 177Lu‐octreotate administration, and registered with non‐rigid deformation of CT volumes, to obtain 177Lu‐octreotate 4D quantitative biodistribution. Local energy deposition from the β disintegrations was assumed. Using Monte Carlo gamma photon transportation, irtGPUMCD computed dose rate at each time point. Average kidney absorbed dose was obtained from 1‐cm3 VOI dose rate samples on each cortex, subjected to a biexponential curve fit. Integration of the latter time‐dose rate curve yielded the renal absorbed dose.The mean renal dose per administered activity was 0.48 ± 0.13 Gy/GBq (range: 0.30–0.71 Gy/GBq). Comparison to another PRRT dosimetry code (VRAK: Voxelized Registration and Kinetics) showed fair accordance with irtGPUMCD (11.4 ± 6.8 %, range: 3.3–26.2%). These results suggest the possibility to use the irtGPUMCD code in order to personalize administered activity in PRRT. This could allow improving clinical outcomes by maximizing per‐cycle tumor doses, without exceeding the tolerable renal dose.
Poster — Thur Eve — 34: Estimation of true cumulative dose to the spinal canal in retreated spine SBRT
Authors: Lee YK , Thibault I , Sahgal A 
Published: September 2014

Decisions on repeat spine SBRT are based on maximum dose constraints to the spinal cord region. The total dose that is assumed to be tolerable is typically the cumulative maximum biological effective dose (BED) calculated irrespective of location of this dose in the two plans. We explore the true spinal cord region BED taking into account BED position in the two plans.Treatment plans of 16 repeat spine SBRT patients were retrospectively evaluated. TBEDmax and TBED0.35cc (sum from two plans) of spinal cord planning organ‐at‐risk volume (SCPRV) and thecal sac (TS) were calculated using α/β of 2Gy. To assess the ‘true’ dose, the first CT was deformably‐ or rigidly‐registered to the second CT. Image registration integrity was visually tested using the modified volumes from the first plan on the recent CT. Using the acquired registration parameters, the voxel‐based BED(VBEDmax, VBED0.35cc) from the two plans were added together and compared to the TBEDmax and TBED0.35cc.The median(range) SCPRV TBEDmax was 98.7(72.5–135.7)Gy and VBEDmax was 76.6(57.3–129.6)Gy (p=0.01). The median(range) TS TBEDmax was 123.2(108.7–261.6)Gy compared to VBEDmax, which was 93.2(59.6–161.2)Gy (p=0.002). The median(range) SCPRV TBED0.35cc was 72.5(53.1–112.1)Gy and VBED0.35cc is 62.2(37.9–93.3)Gy (p=0.01). The median(range) TS TBED0.35cc was 80.3(64.7–120.6)Gy compared to VBED0.35cc was 68.2(45.2–92.1)Gy (p=0.01).When taking location into account, true additive BED to the SCPRV/TS is lower than the current method of estimating BED for repeat spinal SBRT. By incorporating the dose location information, increase in dose to target volume adjacent to SC may be achievable with accurate and precise image registration.
Sci—Thur AM: YIS ‐ 09: Validation of a General Empirically‐Based Beam Model for kV X‐ray Sources
Authors: Poirier Y. , Sommerville M. , Johnstone C.D. , Gräfe J. , Nygren I. , Khan R. , Villareal‐Barajas J.E. , Jacso F. , Tambasco M. 
Published: September 2014

Purpose:To present an empirically‐based beam model for computing dose deposited by kilovoltage (kV) x‐rays and validate it for radiographic, CT, CBCT, superficial, and orthovoltage kV sources.Method and Materials:We modeled a wide variety of imaging (radiographic, CT, CBCT) and therapeutic (superficial, orthovoltage) kV x‐ray sources. The model characterizes spatial variations of the fluence and spectrum independently. The spectrum is derived by matching measured values of the half value layer (HVL) and nominal peak potential (kVp) to computationally‐derived spectra while the fluence is derived from in‐air relative dose measurements. This model relies only on empirical values and requires no knowledge of proprietary source specifications or other theoretical aspects of the kV x‐ray source.To validate the model, we compared measured doses to values computed using our previously validated in‐house kV dose computation software, kVDoseCalc. The dose was measured in homogeneous and anthropomorphic phantoms using ionization chambers and LiF thermoluminescent detectors (TLDs), respectively.Results:The maximum difference between measured and computed dose measurements was within 2.6%, 3.6%, 2.0%, 4.8%, and 4.0% for the modeled radiographic, CT, CBCT, superficial, and the orthovoltage sources, respectively. In the anthropomorphic phantom, the computed CBCT dose generally agreed with TLD measurements, with an average difference and standard deviation ranging from 2.4 ± 6.0% to 5.7 ± 10.3% depending on the imaging technique. Most (42/62) measured TLD doses were within 10% of computed values.Conclusions:The proposed model can be used to accurately characterize a wide variety of kV x‐ray sources using only empirical values.
Poster — Thur Eve — 01: The effect of the number of projections on MTF and CNR in Compton scatter tomography
Authors: Chighvinadze T , Pistorius S 
Published: September 2014

Purpose:To investigate the dependence of the reconstructed image quality on the number of projections in multi‐projection Compton scatter tomography (MPCST). The conventional relationship between the projection number used for reconstruction and reconstructed image quality pertained to CT does not necessarily apply to MPCST, which can produce images from a single projection if the detectors have sufficiently high energy and spatial resolution.Methods:The electron density image was obtained using filtered‐backprojection of the scatter signal over circular arcs formed using Compton equation. The behavior of the reconstructed image quality as a function of the projection number was evaluated through analytical simulations and characterized by CNR and MTF.Results:The increase of the projection number improves the contrast with this dependence being a function of fluence. The number of projections required to approach the asymptotic maximum contrast decreases as the fluence increases. Increasing projection number increases the CNR but not spatial resolution.Conclusions:For MPCST using a 500eV energy resolution and a 2×2mm2 size detector, an adequate image quality can be obtained with a small number of projections provided the incident fluence is high enough. This is conceptually different from conventional CT where a minimum number of projections is required to obtain an adequate image quality. While increasing projection number, even for the lowest dose value, the CNR increases even though the number of photons per projection decreases. The spatial resolution of the image is improved by increasing the sampling within a projection rather than by increasing the number of projections.
Poster — Thur Eve — 11: Validation of the orthopedic metallic artifact reduction tool for CT simulations at the Ottawa Hospital Cancer Centre
Authors: Sutherland J , Foottit C 
Published: September 2014

Metallic implants in patients can produce image artifacts in kilovoltage CT simulation images which can introduce noise and inaccuracies in CT number, affecting anatomical segmentation and dose distributions. The commercial orthopedic metal artifact reduction algorithm (O‐MAR) (Philips Healthcare System) was recently made available on CT simulation scanners at our institution. This study validated the clinical use of O‐MAR by investigating its effects on CT number and dose distributions.O‐MAR corrected and uncorrected images were acquired with a Philips Brilliance Big Bore CT simulator of a cylindrical solid water phantom that contained various plugs (including metal) of known density. CT number accuracy was investigated by determining the mean and standard deviation in regions of interest (ROI) within each plug for uncorrected and O‐MAR corrected images and comparing with no‐metal image values. Dose distributions were calculated using the Monaco treatment planning system. Seven open fields were equally spaced about the phantom around a ROI near the center of the phantom. These were compared to a “correct” dose distribution calculated by overriding electron densities a no‐metal phantom image to produce an image containing metal but no artifacts.An overall improvement in CT number and dose distribution accuracy was achieved by applying the O‐MAR correction. Mean CT numbers and standard deviations were found to be generally improved. Exceptions included lung equivalent media, which is consistent with vendor specified contraindications. Dose profiles were found to vary by ±4% between uncorrected or O‐MAR corrected images with O‐MAR producing doses closer to ground truth.
Poster — Thur Eve — 14: Improving Tissue Segmentation for Monte Carlo Dose Calculation using DECT
Authors: Di Salvio A. , Bedwani S. , Bouchard H. , Carrier J‐F. 
Published: September 2014

Purpose:To improve Monte Carlo dose calculation accuracy through a new tissue segmentation technique with dual energy CT (DECT).Methods:Electron density (ED) and effective atomic number (EAN) can be extracted directly from DECT data with a stoichiometric calibration method. Images are acquired with Monte Carlo CT projections using the user code egs_cbct and reconstructed using an FDK backprojection algorithm. Calibration is performed using projections of a numerical RMI phantom. A weighted parameter algorithm then uses both EAN and ED to assign materials to voxels from DECT simulated images. This new method is compared to a standard tissue characterization from single energy CT (SECT) data using a segmented calibrated Hounsfield unit (HU) to ED curve. Both methods are compared to the reference numerical head phantom. Monte Carlo simulations on uniform phantoms of different tissues using dosxyz_nrc show discrepancies in depth‐dose distributions.Results:Both SECT and DECT segmentation methods show similar performance assigning soft tissues. Performance is however improved with DECT in regions with higher density, such as bones, where it assigns materials correctly 8% more often than segmentation with SECT, considering the same set of tissues and simulated clinical CT images, i.e. including noise and reconstruction artifacts. Furthermore, Monte Carlo results indicate that kV photon beam depth‐dose distributions can double between two tissues of density higher than muscle.Conclusions:A direct acquisition of ED and the added information of EAN with DECT data improves tissue segmentation and increases the accuracy of Monte Carlo dose calculation in kV photon beams.
Genome Sequence of Porphyromonas gingivalis Strain HG66 (DSM 28984)
Authors: Siddiqui Huma , Yoder-Himes Deborah Ruth , Mizgalska Danuta , Nguyen Ky-Anh , Potempa Jan , Olsen Ingar 
Published: September 2014

ABSTRACT

Porphyromonas gingivalis
is considered a major etiologic agent in adult periodontitis. Gingipains are among its most important virulence factors, but their release is unique in strain HG66. We present the genome sequence of HG66 with a single contig of 2,441,680 bp and a G+C content of 48.1%.