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https://www.readbyqxmd.com/read/27894742/metabolic-state-defines-the-response-of-rabbit-ovarian-cells-to-leptin
#1
Abdel Halim Harrath, Olga Østrup, Jan Rafay, Iveta Koničková Florkovičová, Jozef Laurincik, Alexander V Sirotkin
Leptin is a hormone that mediates the effect of the metabolic state on several biological functions, including reproduction. Leptin affects reproductive functions via alterations in the release of hormonal regulators. However, the extent to which caloric restriction (CR) can affect the complex processes of reproduction by other mechanisms, such as altering ovarian functions via direct binding/response to leptin, is unknown. Therefore, the aim of the present study was to show basic ovarian cell functions and CR on the response of ovarian cells to leptin...
November 25, 2016: Reproductive Biology
https://www.readbyqxmd.com/read/27825954/ultra-high-resolution-brain-metabolite-mapping-at-7-t-by-short-tr-hadamard-encoded-fid-mrsi
#2
Gilbert Hangel, Bernhard Strasser, Michal Považan, Eva Heckova, Lukas Hingerl, Roland Boubela, Stephan Gruber, Siegfried Trattnig, Wolfgang Bogner
MRSI in the brain at ≥7T is a technique of great promise, but has been limited mainly by low B0/B1(+)-homogeneity, specific absorption rate restrictions, long measurement times, and low spatial resolution. To overcome these limitations, we propose an ultra-high resolution (UHR) MRSI sequence that provides a 128×128 matrix with a nominal voxel volume of 1.7×1.7×8 mm³ in a comparatively short measurement time. A clinically feasible scan time of 10-20min is reached via a short TR of 200 ms due to an optimised free induction decay-based acquisition with shortened water suppression as well as parallel imaging (PI) using Controlled Aliasing In Parallel Imaging Results IN Higher Acceleration (CAIPIRINHA)...
November 4, 2016: NeuroImage
https://www.readbyqxmd.com/read/27809383/ultra-high-field-rf-coil-development-for-evaluating-upper-extremity-imaging-applications
#3
Shailesh B Raval, Tiejun Zhao, Narayanan Krishnamurthy, Tales Santini, Cynthia Britton, Vijay S Gorantla, Tamer S Ibrahim
The purpose of this study is to develop and evaluate a custom-designed 7  T MRI coil and explore its use for upper extremity applications. An RF system composed of a transverse electromagnetic transmit coil and an eight-channel receive-only array was developed for 7  T upper extremity applications. The RF system was characterized and evaluated using scattering parameters and B1(+) mapping. Finite difference time domain simulations were performed to evaluate the B1(+) field distribution and specific absorption rate for the forearm region of the upper extremity...
November 3, 2016: NMR in Biomedicine
https://www.readbyqxmd.com/read/27795672/mapping-of-a-major-qtl-associated-with-protein-content-on-chromosome-2b-in-hard-red-winter-wheat-triticum-aestivum-l
#4
Yohei Terasawa, Miwako Ito, Tadashi Tabiki, Koichi Nagasawa, Koichi Hatta, Zenta Nishio
A quantitative trait locus (QTL) controlling wheat grain protein content (GPC) and flour protein content (FPC) was identified using doubled haploid (DH) lines developed from a cross between the hard red winter wheat variety 'Yumechikara' with a high protein content used for bread making, and the soft red winter wheat 'Kitahonami' with a low protein content used for Japanese white salted noodles. A single major QTL, QGpc.2B-yume, was identified on the short arm of wheat chromosome 2B for both the GPC and FPC over 3 years of testing...
September 2016: Breeding Science
https://www.readbyqxmd.com/read/27782717/quantitative-assessment-of-biliary-stent-artifacts-on-mr-images-potential-implications-for-target-delineation-in-radiotherapy
#5
Oliver J Gurney-Champion, Thijs Bruins Slot, Eelco Lens, Astrid van der Horst, Remy Klaassen, Hanneke W M van Laarhoven, Geertjan van Tienhoven, Jeanin E van Hooft, Aart J Nederveen, Arjan Bel
PURPOSE: Biliary stents may cause susceptibility artifacts, gradient-induced artifacts, and radio frequency (RF) induced artifacts on magnetic resonance images, which can hinder accurate target volume delineation in radiotherapy. In this study, the authors investigated and quantified the magnitude of these artifacts for stents of different materials. METHODS: Eight biliary stents made of nitinol, platinum-cored nitinol, stainless steel, or polyethylene from seven vendors, with different lengths (57-98 mm) and diameters (3...
October 2016: Medical Physics
https://www.readbyqxmd.com/read/27774641/high-resolution-gradient-recalled-echo-imaging-at-9-4t-using-16-channel-parallel-transmit-simultaneous-multislice-spokes-excitations-with-slice-by-slice-flip-angle-homogenization
#6
Desmond H Y Tse, Christopher J Wiggins, Benedikt A Poser
PURPOSE: In order to fully benefit from the improved signal-to-noise and contrast-to-noise ratios at 9.4T, the challenges of B1+ inhomogeneity and the long acquisition time of high-resolution 2D gradient-recalled echo (GRE) imaging were addressed. THEORY AND METHODS: Flip angle homogenized excitations were achieved by parallel transmission (pTx) of 3-spoke pulses, designed by magnitude least-squares optimization in a slice-by-slice fashion; the acquisition time reduction was achieved by simultaneous multislice (SMS) pulses...
October 23, 2016: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
https://www.readbyqxmd.com/read/27759935/pulmonary-relaxometry-with-inversion-recovery-ultra-fast-steady-state-free-precession-at-1-5t
#7
Grzegorz Bauman, Francesco Santini, Orso Pusterla, Oliver Bieri
PURPOSE: To present a technique for simultaneous mapping of T1 , T2 , and relative spin density (M0 ) in human lung using inversion recovery ultra-fast steady-state free precession (IR-ufSSFP) imaging. METHODS: Pulmonary relaxometry with IR-ufSSFP is based on an interleaved time series acquisition of 2D images acquired at 1.5T. The technique was tested in a phantom and in four healthy volunteers using breath-hold and electrocardiogram triggering. Typically, 30 transient state images were acquired in a single breath-hold within < 10 s...
October 19, 2016: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
https://www.readbyqxmd.com/read/27755746/the-effects-of-climate-downscaling-technique-and-observational-data-set-on-modeled-ecological-responses
#8
Afshin Pourmokhtarian, Charles T Driscoll, John L Campbell, Katharine Hayhoe, Anne M K Stoner
Assessments of future climate change impacts on ecosystems typically rely on multiple climate model projections, but often utilize only one downscaling approach trained on one set of observations. Here, we explore the extent to which modeled biogeochemical responses to changing climate are affected by the selection of the climate downscaling method and training observations used at the montane landscape of the Hubbard Brook Experimental Forest, New Hampshire, USA. We evaluated three downscaling methods: the delta method (or the change factor method), monthly quantile mapping (Bias Correction-Spatial Disaggregation, or BCSD), and daily quantile regression (Asynchronous Regional Regression Model, or ARRM)...
July 2016: Ecological Applications: a Publication of the Ecological Society of America
https://www.readbyqxmd.com/read/27716802/transcriptome-analysis-of-gene-expression-during-chinese-water-chestnut-storage-organ-formation
#9
Libao Cheng, Shuyan Li, Sainan Chen, Yan Wang, Meizhen Yu, Xuehao Chen, Liangjun Li, Jingjing Yin
The product organ (storage organ; corm) of the Chinese water chestnut has become a very popular food in Asian countries because of its unique nutritional value. Corm formation is a complex biological process, and extensive whole genome analysis of transcripts during corm development has not been carried out. In this study, four corm libraries at different developmental stages were constructed, and gene expression was identified using a high-throughput tag sequencing technique. Approximately 4.9 million tags were sequenced, and 4,371,386, 4,372,602, 4,782,494, and 5,276,540 clean tags, including 119,676, 110,701, 100,089, and 101,239 distinct tags, respectively, were obtained after removal of low-quality tags from each library...
2016: PloS One
https://www.readbyqxmd.com/read/27716344/comparison-of-different-cardiovascular-magnetic-resonance-sequences-for-native-myocardial-t1-mapping-at-3t
#10
Tiago Teixeira, Tarik Hafyane, Nikola Stikov, Cansu Akdeniz, Andreas Greiser, Matthias G Friedrich
BACKGROUND: T1 mapping based on cardiovascular magnetic resonance (CMR) is a novel approach using the magnetic relaxation T1 time as a quantitative marker for myocardial tissue composition. Various T1 mapping sequences are being used, with different strengths and weaknesses. Data comparing different sequences head to head however are sparse. METHODS: We compared three T1 mapping sequences, ShMOLLI, MOLLI and SASHA in phantoms and in a mid-ventricular slice of 40 healthy individuals (mean age 59 ± 7 years, 45 % male) with low (68 %) or moderate cardiovascular risk...
October 4, 2016: Journal of Cardiovascular Magnetic Resonance
https://www.readbyqxmd.com/read/27711138/a-potential-magnetic-resonance-imaging-technique-based-on-chemical-exchange-saturation-transfer-for-in-vivo-%C3%AE-aminobutyric-acid-imaging
#11
Gen Yan, Tao Zhang, Zhuozhi Dai, Meizhi Yi, Yanlong Jia, Tingting Nie, Handi Zhang, Gang Xiao, Renhua Wu
PURPOSE: We developed a novel magnetic resonance imaging (MRI) technique based on chemical exchange saturation transfer (CEST) for GABA imaging and investigated the concentration-dependent CEST effect ofGABA in a rat model of brain tumor with blood-brain barrier (BBB) disruption. MATERIALS AND METHODS: All MRI studies were performed using a 7.0-T Agilent MRI scanner. Z-spectra for GABA were acquired at 7.0 T, 37°C, and a pH of 7.0 using varying B1 amplitudes. CEST images of phantoms with different concentrations of GABA solutions (pH, 7...
2016: PloS One
https://www.readbyqxmd.com/read/27705848/slow-electron-velocity-map-imaging-study-of-aniline-via-resonance-enhanced-two-photon-ionization-method
#12
Zehua Qu, Zhengbo Qin, Xianfeng Zheng, Hui Wang, Guanxin Yao, Xianyi Zhang, Zhifeng Cui
Slow electron velocity-map imaging (SEVI) of aniline has been investigated via two-color resonant-enhanced two-photo (1+1') ionization (2C-R2PI) method. A number of vibrational frequencies in the first excited state of neutral (S1) and (2)B1 ground electronic state of cation (D0) have been accurately determined. In addition, photoelectron angular distributions (PADs) in the two-step transitions are presented and reveal a near threshold shape resonance in the ionization of aniline. The SEVI spectra taken via various S1 intermediate states provide the detailed vibrational structures of D0 state and directly deduce the accurate adiabatic ionization potential (IP) of 62,271±6cm(-1)...
September 28, 2016: Spectrochimica Acta. Part A, Molecular and Biomolecular Spectroscopy
https://www.readbyqxmd.com/read/27697007/quantitative-liver-function-analysis-volumetric-t1-mapping-with-fast-multisection-b1-inhomogeneity-correction-in-hepatocyte-specific-contrast-enhanced-liver-mr-imaging
#13
Jeong Hee Yoon, Jeong Min Lee, Eunju Kim, Tomoyuki Okuaki, Joon Koo Han
Purpose To determine whether B1 inhomogeneity-corrected volumetric T1 maps of gadoxetic acid-enhanced liver magnetic resonance (MR) imaging are able to demonstrate global liver function and functional heterogeneity in patients with cirrhosis and to investigate their relationship with the development of hepatic insufficiency and decompensation. Materials and Methods This institutional review board-approved retrospective study with waiver of informed consent included 234 consecutive patients who underwent gadoxetic acid-enhanced liver MR imaging, including B1 inhomogeneity-corrected volumetric T1 mapping...
October 3, 2016: Radiology
https://www.readbyqxmd.com/read/27672298/different-pre-s-deletion-patterns-and-their-association-with-hepatitis-b-virus-genotypes
#14
Bing-Fang Chen
AIM: To investigate the associations of different types of pre-S deletions with hepatitis B virus (HBV) genotypes. METHODS: The sequences of the pre-S region, basal core promoter (BCP) mutation, and precore (PC) mutation were examined through direct DNA sequencing or clonal analysis and sequencing in 273 HBV carriers, namely 55 asymptomatic carriers, 55 carriers with chronic hepatitis (CH), 55 with liver cirrhosis (LC), 53 with liver cirrhotic hepatocellular carcinoma (LC-HCC), and 55 with noncirrhotic HCC...
September 21, 2016: World Journal of Gastroenterology: WJG
https://www.readbyqxmd.com/read/27662843/qtl-mapping-of-fusarium-head-blight-resistance-in-three-related-durum-wheat-populations
#15
Noemie Prat, Camille Guilbert, Ursa Prah, Elisabeth Wachter, Barbara Steiner, Thierry Langin, Olivier Robert, Hermann Buerstmayr
The QTL Fhb1 was successfully introgressed and validated in three durum wheat populations. The novel germplasm and the QTL detected will support improvement of Fusarium resistance in durum wheat. Durum wheat (Triticum durum Desf.) is particularly susceptible to Fusarium head blight (FHB) and breeding for resistance is hampered by limited genetic variation within this species. To date, resistant sources are mainly available in a few wild relative tetraploid wheat accessions. In this study, the effect of the well-known hexaploid wheat (Triticum aestivum L...
September 23, 2016: TAG. Theoretical and Applied Genetics. Theoretische und Angewandte Genetik
https://www.readbyqxmd.com/read/27658506/comparison-of-spoiled-gradient-echo-and-steady-state-free-precession-imaging-for-native-myocardial-t1-mapping-using-the-slice-interleaved-t1-mapping-stone-sequence
#16
Jihye Jang, Steven Bellm, Sébastien Roujol, Tamer A Basha, Maryam Nezafat, Shingo Kato, Sebastian Weingärtner, Reza Nezafat
Cardiac T1 mapping allows non-invasive imaging of interstitial diffuse fibrosis. Myocardial T1 is commonly calculated by voxel-wise fitting of the images acquired using balanced steady-state free precession (SSFP) after an inversion pulse. However, SSFP imaging is sensitive to B1 and B0 imperfection, which may result in additional artifacts. A gradient echo (GRE) imaging sequence has been used for myocardial T1 mapping; however, its use has been limited to higher magnetic field to compensate for the lower signal-to-noise ratio (SNR) of GRE versus SSFP imaging...
October 2016: NMR in Biomedicine
https://www.readbyqxmd.com/read/27614105/bradykinin-receptor-blockade-restores-the-baroreflex-control-of-renal-sympathetic-nerve-activity-in-cisplatin-induced-renal-failure-rats
#17
M H Abdulla, M Duff, H Swanton, E J Johns
AIM: This study investigated the effect of renal bradykinin B1 and B2 receptor blockade on the high- and low-pressure baroreceptor reflex regulation of renal sympathetic nerve activity (RSNA) in rats with cisplatin-induced renal failure. METHODS: Cisplatin (5 mg/kg) or saline was given intraperitoneally 4 days prior to study. Following chloralose/urethane anaesthesia, rats were prepared for measurement of mean arterial pressure (MAP), heart rate and RSNA and received intrarenal infusions of either Lys-[des-Arg(9) , Leu(8) ]-bradykinin (LBK), a bradykinin B1 receptor blocker, or bradyzide (BZ), a bradykinin B2 receptor blocker...
November 2016: Acta Physiologica
https://www.readbyqxmd.com/read/27602037/characterizing-two-inter-specific-bin-maps-for-the-exploration-of-the-qtls-genes-that-confer-three-soybean-evolutionary-traits
#18
Wubin Wang, Meifeng Liu, Yufeng Wang, Xuliang Li, Shixuan Cheng, Liping Shu, Zheping Yu, Jiejie Kong, Tuanjie Zhao, Junyi Gai
Annual wild soybean (Glycine soja Sieb. and Zucc.), the wild progenitor of the cultivated soybean [Glycine max (L.) Merr.], is valuable for improving the later. The construction of a linkage map is crucial for studying the genetic differentiation between these species, but marker density is the main factor limiting the accuracy of such a map. Recent advances in next-generation sequencing technologies allow for the generation of high-density linkage maps. Here, two sets of inter-specific recombinant inbred line populations, named NJIRNP and NJIR4P, composed of 284 and 161 lines, respectively, were generated from the same wild male parent, PI 342618B, and genotyped by restriction-site-associated DNA sequencing...
2016: Frontiers in Plant Science
https://www.readbyqxmd.com/read/27599782/motion-robust-cardiac-b1-mapping-at-3t-using-interleaved-bloch-siegert-shifts
#19
Sebastian Weingärtner, Fabian Zimmer, Gregory J Metzger, Kâmil Uğurbil, Pierre-Francois Van de Moortele, Mehmet Akçakaya
PURPOSE: To develop and evaluate a robust motion-insensitive Bloch-Siegert shift based B1+ mapping method in the heart. METHODS: Cardiac Bloch-Siegert B1+ mapping was performed with interleaved positive and negative off-resonance shifts and diastolic spoiled gradient echo imaging in 12 heartbeats. Numerical simulations were performed to study the impact of respiratory motion. The method was compared with three-dimensional (3D) actual flip angle imaging (AFI) and two-dimensional (2D) saturated double angle method (SDAM) in phantom scans...
September 7, 2016: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
https://www.readbyqxmd.com/read/27579566/creatine-kinase-rate-constant-in-the-human-heart-measured-with-3d-localization-at-7-tesla
#20
William T Clarke, Matthew D Robson, Stefan Neubauer, Christopher T Rodgers
PURPOSE: We present a new Bloch-Siegert four Angle Saturation Transfer (BOAST) method for measuring the creatine kinase (CK) first-order effective rate constant kf in human myocardium at 7 tesla (T). BOAST combines a variant of the four-angle saturation transfer (FAST) method using amplitude-modulated radiofrequency pulses, phosphorus Bloch-Siegert B1+-mapping to determine the per-voxel flip angles, and nonlinear fitting to Bloch simulations for postprocessing. METHODS: Optimal flip angles and repetition time parameters were determined from Monte Carlo simulations...
August 31, 2016: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
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