bluuebunny/crossref_metadata_2025_split huggingface dataset:
Prefrontal cortex white matter tracts in prodromal Huntington disease
Authors: Matsui Joy T. , Vaidya Jatin G. , Wassermann Demian , Kim Regina Eunyoung , Magnotta Vincent A. , Johnson Hans J. , Paulsen Jane S. ,   PREDICT‐HD Investigators and Coordinators of the Huntington Study Group
Published: July 2015

AbstractHuntington disease (HD) is most widely known for its selective degeneration of striatal neurons but there is also growing evidence for white matter (WM) deterioration. The primary objective of this research was to conduct a large‐scale analysis using multisite diffusion‐weighted imaging (DWI) tractography data to quantify diffusivity properties along major prefrontal cortex WM tracts in prodromal HD. Fifteen international sites participating in the PREDICT‐HD study collected imaging and neuropsychological data on gene‐positive HD participants without a clinical diagnosis (i.e., prodromal) and gene‐negative control participants. The anatomical prefrontal WM tracts of the corpus callosum (PFCC), anterior thalamic radiations (ATRs), inferior fronto‐occipital fasciculi (IFO), and uncinate fasciculi (UNC) were identified using streamline tractography of DWI. Within each of these tracts, tensor scalars for fractional anisotropy, mean diffusivity, radial diffusivity, and axial diffusivity coefficients were calculated. We divided prodromal HD subjects into three CAG‐age product (CAP) groups having Low, Medium, or High probabilities of onset indexed by genetic exposure. We observed significant differences in WM properties for each of the four anatomical tracts for the High CAP group in comparison to controls. Additionally, the Medium CAP group presented differences in the ATR and IFO in comparison to controls. Furthermore, WM alterations in the PFCC, ATR, and IFO showed robust associations with neuropsychological measures of executive functioning. These results suggest long‐range tracts essential for cross‐region information transfer show early vulnerability in HD and may explain cognitive problems often present in the prodromal stage. Hum Brain Mapp 36:3717–3732, 2015. © 2015 Wiley Periodicals, Inc.
Age‐related changes in the topological organization of the white matter structural connectome across the human lifespan
Authors: Zhao Tengda , Cao Miao , Niu Haijing , Zuo Xi‐Nian , Evans Alan , He Yong , Dong Qi , Shu Ni 
Published: July 2015

AbstractLifespan is a dynamic process with remarkable changes in brain structure and function. Previous neuroimaging studies have indicated age‐related microstructural changes in specific white matter tracts during development and aging. However, the age‐related alterations in the topological architecture of the white matter structural connectome across the human lifespan remain largely unknown. Here, a cohort of 113 healthy individuals (ages 9–85) with both diffusion and structural MRI acquisitions were examined. For each participant, the high‐resolution white matter structural networks were constructed by deterministic fiber tractography among 1024 parcellation units and were quantified with graph theoretical analyses. The global network properties, including network strength, cost, topological efficiency, and robustness, followed an inverted U‐shaped trajectory with a peak age around the third decade. The brain areas with the most significantly nonlinear changes were located in the prefrontal and temporal cortices. Different brain regions exhibited heterogeneous trajectories: the posterior cingulate and lateral temporal cortices displayed prolonged maturation/degeneration compared with the prefrontal cortices. Rich‐club organization was evident across the lifespan, whereas hub integration decreased linearly with age, especially accompanied by the loss of frontal hubs and their connections. Additionally, age‐related changes in structural connections were predominantly located within and between the prefrontal and temporal modules. Finally, based on the graph metrics of structural connectome, accurate predictions of individual age were obtained (r = 0.77). Together, the data indicated a dynamic topological organization of the brain structural connectome across human lifespan, which may provide possible structural substrates underlying functional and cognitive changes with age. Hum Brain Mapp 36:3777–3792, 2015. © 2015 Wiley Periodicals, Inc.
Intrinsic brain activity as a diagnostic biomarker in children with benign epilepsy with centrotemporal spikes
Authors: Zhu Yihong , Yu Yang , Shinkareva Svetlana V. , Ji Gong‐Jun , Wang Jue , Wang Zhong‐Jin , Zang Yu‐Feng , Liao Wei , Tang Ye‐Lei 
Published: July 2015

AbstractBenign epilepsy with centrotemporal spikes (BECTS) is often associated with neural circuit dysfunction, particularly during the transient active state characterized by interictal epileptiform discharges (IEDs). Little is known, however, about the functional neural circuit abnormalities in BECTS without IEDs, or if such abnormalities could be used to differentiate BECTS patients without IEDs from healthy controls (HCs) for early diagnosis. To this end, we conducted resting‐state functional magnetic resonance imaging (RS‐fMRI) and simultaneous Electroencephalogram (EEG) in children with BECTS (n = 43) and age‐matched HC (n = 28). The simultaneous EEG recordings distinguished BECTS with IEDs (n = 20) from without IEDs (n = 23). Intrinsic brain activity was measured in all three groups using the amplitude of low frequency fluctuation at rest. Compared to HC, BECTS patients with IEDs exhibited an intrinsic activity abnormality in the thalamus, suggesting that thalamic dysfunction could contribute to IED emergence while patients without IEDs exhibited intrinsic activity abnormalities in middle frontal gyrus and superior parietal gyrus. Using multivariate pattern classification analysis, we were able to differentiate BECTS without IEDs from HCs with 88.23% accuracy. BECTS without epileptic transients can be distinguished from HC and BECTS with IEDs by unique regional abnormalities in resting brain activity. Both transient abnormalities as reflected by IEDs and chronic abnormalities as reflected by RS‐fMRI may contribute to BECTS development and expression. Intrinsic brain activity and multivariate pattern classification techniques are promising tools to diagnose and differentiate BECTS syndromes. Hum Brain Mapp 36:3878–3889, 2015. © 2015 Wiley Periodicals, Inc.
Interactions between glutamate, dopamine, and the neuronal signature of response inhibition in the human striatum
Authors: Lorenz Robert C. , Gleich Tobias , Buchert Ralph , Schlagenhauf Florian , Kühn Simone , Gallinat Jürgen 
Published: July 2015

AbstractResponse inhibition is a basic mechanism in cognitive control and dysfunctional in major psychiatric disorders. The neuronal mechanisms are in part driven by dopamine in the striatum. Animal data suggest a regulatory role of glutamate on the level of the striatum. We used a trimodal imaging procedure of the human striatum including F18‐DOPA positron emission tomography, proton magnetic resonance spectroscopy, and functional magnetic resonance imaging of a stop signal task. We investigated dopamine synthesis capacity and glutamate concentration in vivo and their relation to functional properties of response inhibition. A mediation analysis revealed a significant positive association between dopamine synthesis capacity and inhibition‐related neural activity in the caudate nucleus. This relationship was significantly mediated by striatal glutamate concentration. Furthermore, stop signal reaction time was inversely related to striatal activity during inhibition. The data show, for the first time in humans, an interaction between dopamine, glutamate, and the neural signature of response inhibition in the striatum. This finding stresses the importance of the dopamine–glutamate interaction for behavior and may facilitate the understanding of psychiatric disorders characterized by impaired response inhibition. Hum Brain Mapp 36:4031–4040, 2015. © 2015 Wiley Periodicals, Inc.
Segregation of face sensitive areas within the fusiform gyrus using global signal regression? A study on amygdala resting‐state functional connectivity
Authors: Kruschwitz Johann D. , Meyer‐Lindenberg Andreas , Veer Ilya M. , Wackerhagen Carolin , Erk Susanne , Mohnke Sebastian , Pöhland Lydia , Haddad Leila , Grimm Oliver , Tost Heike , Romanczuk‐Seiferth Nina , Heinz Andreas , Walter Martin , Walter Henrik 
Published: July 2015

AbstractThe application of global signal regression (GSR) to resting‐state functional magnetic resonance imaging data and its usefulness is a widely discussed topic. In this article, we report an observation of segregated distribution of amygdala resting‐state functional connectivity (rs‐FC) within the fusiform gyrus (FFG) as an effect of GSR in a multi‐center‐sample of 276 healthy subjects. Specifically, we observed that amygdala rs‐FC was distributed within the FFG as distinct anterior versus posterior clusters delineated by positive versus negative rs‐FC polarity when GSR was performed. To characterize this effect in more detail, post hoc analyses revealed the following: first, direct overlays of task‐functional magnetic resonance imaging derived face sensitive areas and clusters of positive versus negative amygdala rs‐FC showed that the positive amygdala rs‐FC cluster corresponded best with the fusiform face area, whereas the occipital face area corresponded to the negative amygdala rs‐FC cluster. Second, as expected from a hierarchical face perception model, these amygdala rs‐FC defined clusters showed differential rs‐FC with other regions of the visual stream. Third, dynamic connectivity analyses revealed that these amygdala rs‐FC defined clusters also differed in their rs‐FC variance across time to the amygdala. Furthermore, subsample analyses of three independent research sites confirmed reliability of the effect of GSR, as revealed by similar patterns of distinct amygdala rs‐FC polarity within the FFG. In this article, we discuss the potential of GSR to segregate face sensitive areas within the FFG and furthermore discuss how our results may relate to the functional organization of the face‐perception circuit. Hum Brain Mapp 36:4089–4103, 2015. © 2015 Wiley Periodicals, Inc.
Validation of tractography: Comparison with manganese tracing
Authors: Knösche Thomas R. , Anwander Alfred , Liptrot Matthew , Dyrby Tim B. 
Published: July 2015

AbstractIn this study, we used invasive tracing to evaluate white matter tractography methods based on ex vivo diffusion‐weighted magnetic resonance imaging (dwMRI) data. A representative selection of tractography methods were compared to manganese tracing on a voxel‐wise basis, and a more qualitative assessment examined whether, and to what extent, certain fiber tracts and gray matter targets were reached. While the voxel‐wise agreement was very limited, qualitative assessment revealed that tractography is capable of finding the major fiber tracts, although there were some differences between the methods. However, false positive connections were very common and, in particular, we discovered that it is not possible to achieve high sensitivity (i.e., few false negatives) and high specificity (i.e., few false positives) at the same time. Closer inspection of the results led to the conclusion that these problems mainly originate from regions with complex fiber arrangements or high curvature and are not easily resolved by sophisticated local models alone. Instead, the crucial challenge in making tractography a truly useful and reliable tool in brain research and neurology lies in the acquisition of better data. In particular, the increase of spatial resolution, under preservation of the signal‐to‐noise‐ratio, is key. Hum Brain Mapp 36:4116–4134, 2015. © 2015 The Authors Human Brain Mapping Published by Wiley Periodicals, Inc.
Neural correlates of self‐injurious behavior in Prader–Willi syndrome
Authors: Klabunde Megan , Saggar Manish , Hustyi Kristin M. , Hammond Jennifer L. , Reiss Allan L. , Hall Scott S. 
Published: July 2015

AbstractIndividuals with Prader–Willi syndrome (PWS), a genetic disorder caused by mutations to the q11‐13 region on chromosome 15, commonly show severe skin‐picking behaviors that can cause open wounds and sores on the body. To our knowledge, however, no studies have examined the potential neural mechanisms underlying these behaviors. Seventeen individuals with PWS, aged 6–25 years, who showed severe skin‐picking behaviors, were recruited and scanned on a 3T scanner. We used functional magnetic resonance imaging (fMRI) while episodes of skin picking were recorded on an MRI‐safe video camera. Three participants displayed skin picking continuously throughout the scan, three participants did not display skin picking, and the data for one participant evidenced significant B0 inhomogeneity that could not be corrected. The data for the remaining 10 participants (six male, four female) who displayed a sufficient number of picking and nonpicking episodes were subjected to fMRI analysis. Results showed that regions involved in interoceptive, motor, attention, and somatosensory processing were activated during episodes of skin‐picking behavior compared with nonpicking episodes. Scores obtained on the Self‐Injury Trauma scale were significantly negatively correlated with mean activation within the right insula and left precentral gyrus. These data indicate that itch and pain processes appear to underlie skin‐picking behaviors in PWS, suggesting that interoceptive disturbance may contribute to the severity and maintenance of abnormal skin‐picking behaviors in PWS. Implications for treatments are discussed. Hum Brain Mapp 36:4135–4143, 2015. © 2015 Wiley Periodicals, Inc.
Pharmacological inhibition of apical sodium‐dependent bile acid transporter changes bile composition and blocks progression of sclerosing cholangitis in multidrug resistance 2 knockout mice
Authors: Miethke Alexander G. , Zhang Wujuan , Simmons Julia , Taylor Amy E. , Shi Tiffany , Shanmukhappa Shiva Kumar , Karns Rebekah , White Shana , Jegga Anil G. , Lages Celine S. , Nkinin Stephenson , Keller Bradley T. , Setchell Kenneth D.R. 
Published: July 2015

Deficiency of multidrug resistance 2 (mdr2), a canalicular phospholipid floppase, leads to excretion of low‐phospholipid “toxic” bile causing progressive cholestasis. We hypothesize that pharmacological inhibition of the ileal, apical sodium‐dependent bile acid transporter (ASBT), blocks progression of sclerosing cholangitis in mdr2–/– mice. Thirty‐day‐old, female mdr2–/– mice were fed high‐fat chow containing 0.006% SC‐435, a minimally absorbed, potent inhibitor of ASBT, providing, on average, 11 mg/kg/day of compound. Bile acids (BAs) and phospholipids were measured by mass spectrometry.
Compared with untreated mdr2–/– mice, SC‐435 treatment for 14 days increased fecal BA excretion by 8‐fold, lowered total BA concentration in liver by 65%, reduced total BA and individual hydrophobic BA concentrations in serum by >98%, and decreased plasma alanine aminotransferase, total bilirubin, and serum alkaline phosphatase levels by 86%, 93%, and 55%, respectively. Liver histology of sclerosing cholangitis improved, and extent of fibrosis decreased concomitant with reduction of hepatic profibrogenic gene expression. Biliary BA concentrations significantly decreased and phospholipids remained low and unchanged with treatment. The phosphatidylcholine (PC)/BA ratio in treated mice corrected toward a ratio of 0.28 found in wild‐type mice, indicating decreased bile toxicity. Hepatic RNA sequencing studies revealed up‐regulation of putative anti‐inflammatory and antifibrogenic genes, including Ppara and Igf1, and down‐regulation of several proinflammatory genes, including Ccl2 and Lcn2, implicated in leukocyte recruitment. Flow cytometric analysis revealed significant reduction of frequencies of hepatic CD11b+F4/80+ Kupffer cells and CD11b+Gr1+ neutrophils, accompanied by expansion of anti‐inflammatory Ly6C– monocytes in treated mdr2–/– mice. Conclusion: Inhibition of ASBT reduces BA pool size and retention of hydrophobic BA, favorably alters the biliary PC/BA ratio, profoundly changes the hepatic transcriptome, attenuates recruitment of leukocytes, and abrogates progression of murine sclerosing cholangitis. (Hepatology 2016;63:512–523)
Direct Arylation of 5‐Iodouracil and 5‐Iodouridine with Heteroarenes and Benzene via Photochemical Reaction
Authors: Yang Qian , Wei Tao , He Yun , Liang Yong , Zhang Zun‐Ting 
Published: July 2015

AbstractA method for the direct arylation of 5‐iodouracil and 5‐iodouridine was found to proceed in moderate yields. By irradiating mixtures of 5‐iodouracil or 5‐iodouridine and a series of five‐membered heterocycles such as 1H‐pyrrole, furan, 2‐methylfuran, 1‐methyl‐1H‐pyrrole, thiophene, as well as benzene in MeCN/H2O with a Hg lamp, 5‐aryluracils and 5‐aryluridines were synthesized. The reaction proceeded smoothly without the requirement of adding any transition metals or ligands.
An Efficient and Chemoselective Knoevenagel/Hemiketalization Process for the Synthesis of New 2H‐Chromenes in a One‐Pot Three‐Component Reaction
Authors: Rao Lenka Chandrasekhara , Kumar Nandigama Satish , Meshram Harshadas Mitaram 
Published: July 2015

AbstractA novel L‐proline‐catalyzed mild and ecological approach towards the synthesis of 2H‐chromene derivatives was achieved by Knoevenagel reaction followed by an intramolecular hemiketalization process. In the present protocol, chemoselectivity has been successfully achieved by using L‐proline as catalyst. This eco‐friendly and chemoselective reaction provided an alternative synthetic method to prepare previously unknown 2H‐chromene derivatives in a one‐pot reaction.
Computational Studies on Intramolecular Cycloadditions of Azidoenynes and Azidobutenenitriles to Give 6H‐Pyrrolo[1,2‐c][1,2,3]triazoles and 5H‐Pyrrolo[1,2‐d]tetrazoles
Authors: Audran Gérard , Brémond Paul , El Abed Douniazad , Marque Sylvain R. A. , Siri Didier , Santelli Maurice 
Published: July 2015

AbstractEnergetics of intramolecular cycloadditions of azidoenynes and azidobutenenitriles to give 6H‐pyrrolo[1,2‐c][1,2,3]triazoles and 5H‐pyrrolo[1,2‐d]tetrazoles have been calculated at the B3LYP/6.311++G(3df,3pd) level of theory in ideal gas and in H2O as solvent. Stabilities of the corresponding anions, tautomers, and isomers are discussed. Transition states of the cyclization of parent compounds are determined at the same level of theory.
The prognostic significance of EBV DNA load and EBER status in diagnostic specimens from diffuse large B‐cell lymphoma patients
Authors: Okamoto Akinao , Yanada Masamitsu , Inaguma Yoko , Tokuda Masutaka , Morishima Satoko , Kanie Tadaharu , Yamamoto Yukiya , Mizuta Shuichi , Akatsuka Yoshiki , Yoshikawa Tetsushi , Mizoguchi Yoshikazu , Nakamura Shigeo , Okamoto Masataka , Emi Nobuhiko 
Published: July 2015

AbstractEpstein–Barr virus (EBV)‐encoded small RNA in situ hybridization (EBER‐ISH) is a widely accepted method to evaluate EBV involvement in diffuse large B‐cell lymphoma (DLBCL), although little is known regarding associations between EBV DNA load and the EBER status and whether EBV DNA load data provide additional clinical information. In this study, we quantified EBV DNA load in diagnostic specimens from DLBCL patients diagnosed at our hospital to evaluate clinical implications of EBV DNA load in diagnostic specimens as contrasted with EBER‐ISH. Among 140 DLBCL patients without underlying immunodeficiency, 51 were evaluable for both EBER and EBV DNA load, 83 for EBER only and one for EBV DNA load only. The median EBV DNA load was 708 copies/µg. Although EBV DNA load was significantly higher for EBER‐positive patients than for EBER‐negative patients (p < 0.001), EBV DNA was detected in up to 72% of EBER‐negative patients. Progression‐free survival and overall survival were significantly worse for patients with EBV DNA load above 700 copies/µg than for those with EBV DNA load below 700 copies/µg (p = 0.009 and p = 0.003); they were also significantly worse for EBER‐positive patients than for EBER‐negative patients (p < 0.001 and p = 0.001). Even among EBER‐negative patients, higher EBV DNA load conferred worse progression‐free survival and overall survival (p = 0.041 and p = 0.013). These findings indicate that EBV DNA load in diagnostic specimens is not a simple surrogate for the EBER status and may be a potential biomarker associated with EBV involvement and prognosis in DLBCL. Copyright © 2015 John Wiley & Sons, Ltd.
Obstacles to long‐term soil moisture monitoring with heated distributed temperature sensing
Authors: Sourbeer John J. , Loheide Steven P. 
Published: July 2015

AbstractThe field deployment of a heated distributed temperature sensor (DTS) for over three years has revealed two obstacles to estimating soil moisture (θ) that may hamper subsurface DTS applications as well as use of other subsurface thermal probes. The first observed obstacle was a hysteretic response of the DTS sensor. The relationship between θ and the temperature response (∆T) within the cable was not only dependent on θ of the soil, but also on the previous wetting and drying cycles leading to that state. The second observed obstacle was soil structure healing. Soil structure healing causes the relationship between ∆T and θ to evolve through time; this calibration curve becomes flatter, or less sensitive, as the surrounding soil makes better contact with the cable. Effects of the hysteretic response of the instrument and soil structure healing are largely the result of small gaps between the cable and soil. These small gaps can be approximated by a contact resistance between the cable and soil. In this article we characterize the occurrence of hysteretic and soil structure healing effects from field data and parameterize contact resistance by simulating heat transfer using a numerical modelling approach Copyright © 2015 John Wiley & Sons, Ltd.