bluuebunny/crossref_metadata_2025_split huggingface dataset:
β‐Cryptoxanthin uptake in THP‐1 macrophages upregulates the CYP27A1 signaling pathway
Authors: Fu Hongfei , Wu Canjie , Riaz Hasan , Zhang Hualin , Han Li , Bai Liya , Yang Feifei , Yang Liguo 
Published: October 2013

ScopeMitochondrial sterol 27‐hydroxylase (CYP27A1), a mediator of cholesterol homeostasis, is reported to exhibit antiatherogenic properties. Many studies suggested that all‐trans retinoic acid can be used to treat atherosclerosis through retinoic acid receptor (RAR)‐mediated upregulation of CYP27A1 expression. In this study, we hypothesized that β‐cryptoxanthin (β‐cry), as a natural ligand of RAR, might act as antiatherogenic agent by upregulating CYP27A1.Methods and resultsWe found that β‐cry treatment significantly upregulated genes involved in the uptake, transport, and metabolism of retinoids and the signaling pathway of CYP27A1 expression in THP‐1 macrophages as detected by microarray analysis. Meanwhile, intracellular levels of β‐cry were correlated to the concentration and exposure time of the treatment. The expression of genes, involved in signaling pathway of CYP27A1, was dramatically decreased due to repressed activity of RAR. Higher level of 27‐hydroxycholesterol was detected in β‐cry‐treated macrophages by HPLC. Docking simulation showed that β‐cry could interact with cellular retinoic acid binding protein 2. These findings were further confirmed through microarray results.ConclusionOur results provide strong evidence that β‐cry can be actively taken up by THP‐1 macrophages and exhibits antiatherogenic effect on THP‐1 macrophages by inducing CYP27A1 expression via RAR.
Immunological behavior of in vitro digested egg‐white lysozyme
Authors: Jiménez‐Saiz Rodrigo , Benedé Sara , Miralles Beatriz , López‐Expósito Iván , Molina Elena , López‐Fandiño Rosina 
Published: October 2013

ScopeBesides its antimicrobial properties, lysozyme (LYS) is one of the major allergens from hen egg. This paper addresses the identification of the peptides produced upon in vitro gastrointestinal digestion of LYS, together with their IgE‐binding and biological activity as a contribution to the understanding of what makes it a relevant allergen.Methods and resultsSimulated in vitro gastrointestinal digestion together with IgE binding, basophil degranulation, and peripheral blood mononuclear cells stimulation experiments were carried out. Identification of the fragments released was performed by HPLC‐MS/MS and the immunoreactive products were analyzed by MALDI‐TOF/TOF. Results showed that in vitro gastric and gastroduodenal digests of LYS maintained IgE binding, basophil activation capacity, and preserved T‐cell immunogenicity. These biological activities could be attributed to either the persistence of intact LYS, due to incomplete gastric degradation and subsequent duodenal precipitation, the formation of fragment f(24–129) by chymotrypsin action on the soluble intact protein, or the release, upon combined gastric and pancreatic digestion, of immunoreactive peptides linked by disulphide bonds containing the epitopes f(57–83) and f(108–122).ConclusionThe pH of gastric hydrolysis greatly determined the extent of subsequent duodenal digestion of LYS and the disclosure of relevant epitopes that could increase its allergenic potential.
Induced pluripotent stem cells from goat fibroblasts
Authors: Song Hui , Li Hui , Huang Mingrui , Xu Dan , Gu Chenghao , Wang Ziyu , Dong Fulu , Wang Feng 
Published: October 2013

SUMMARYEmbryonic stem cells (ESCs) are a powerful model for genetic engineering, studying developmental biology, and modeling disease. To date, ESCs have been established from the mouse (Evans and Kaufman, 1981, Nature 292:154–156), non‐human primates (Thomson et al., , Proc Nat Acad Sci USA 92:7844–7848), humans (Thomson et al., 1998, Science 282:1145–1147), and rats (Buehr et al., , Cell 135:1287–1298); however, the derivation of ESCs from domesticated ungulates such as goats, sheep, cattle, and pigs have not been successful. Alternatively, induced pluripotent stem cells (iPSCs) can be generated by reprogramming somatic cells with several combinations of genes encoding transcription factors (OCT3/4, SOX2, KLF4, cMYC, LIN28, and NANOG). To date, iPSCs have been isolated from various species, but only limited information is available regarding goat iPSCs (Ren et al., 2011, Cell Res 21:849–853). The objectives of this study were to generate goat iPSCs from fetal goat primary ear fibroblasts using lentiviral transduction of four human transcription factors: OCT4, SOX2, KLF4, and cMYC. The goat iPSCs were successfully generated by co‐culture with mitomycin C‐treated mouse embryonic fibroblasts using medium supplemented with knockout serum replacement and human basic fibroblast growth factor. The goat iPSCs colonies are flat, compact, and closely resemble human iPSCs. They have a normal karyotype; stain positive for alkaline phosphatase, OCT4, and NANOG; express endogenous pluripotency genes (OCT4, SOX2, cMYC, and NANOG); and can spontaneously differentiate into three germ layers in vitro and in vivo. Mol. Reprod. Dev. 80: 1009–1017, 2013. © 2013 Wiley Periodicals, Inc.
Rapamycin‐sensitive mTORC1 signaling is involved in physiological primordial follicle activation in mouse ovary
Authors: Tong Yuanyuan , Li Fei , Lu Yi , Cao Yanlan , Gao Jimin , Liu Jianghuai 
Published: October 2013

SUMMARYIn mammals, resting female oocytes reside in primordial ovarian follicles. An individual primordial follicle may stay quiescent for a protracted period of time before initiating follicular growth, which is also termed “activation.” Female reproductive capacity is sustained by the gradual, streamlined activation of the entire population of primordial follicles, but this process also results in reproductive senescence in older animals. Based on the recent findings that genetically triggered, excessive mammalian target of rapamycin complex 1 (mTORC1) activation in mouse oocytes leads to accelerated primordial follicle activation, we examined the necessity of mTORC1 signaling in physiological primordial follicle activation. We found that induction of oocyte mTORC1 activity is associated with early follicular growth in neonatal mouse ovaries. Pharmacological inhibition of mTORC1 activity in vivo by rapamycin treatment leads to a marked, but partial, suppression of primordial follicle activation. The suppressive effect of rapamycin on primordial follicle activation was reproduced in cultured ovaries. While rapamycin did not apparently affect several plausible cellular targets in neonatal mouse ovaries, such as mTORC2, AKT, or cyclin‐dependent kinase (CDK) inhibitor p27‐KIP1, its inhibitory effect on Cyclin A2 gene expression implies that mTORC1 signaling in oocytes may engage a Cyclin A/CDK regulatory network that promotes primordial follicle activation. The current work strengthens the concept that mTORC1‐dependent events in the oocytes of primordial follicles may represent potential targets for intervention in humans to slow the depletion of the ovarian reserve. Mol. Reprod. Dev. 80: 1018–1034, 2013. © 2013 Wiley Periodicals, Inc.
Influence of Acrylated Lactide‐Caprolactone Macromonomers on the Performance of High Biomass Content Pressure‐Sensitive Adhesives
Authors: Pu Gang , Hauge Drew A. , Gu Cheng , Zhang Jilin , Severtson Steven J. , Wang Wenjun , Houtman Carl J. 
Published: October 2013

AbstractResults from a study of the influence of macromonomer (MM) composition on the properties of high‐biomass content adhesive polymers are reported. Pressure‐sensitive adhesives (PSAs) are synthesized through miniemulsion polymerization of n‐butyl acrylate, vinyl acetate, and methacrylic acid with lactide‐containing MMs. The MMs are generated from bulk ring‐opening polymerizations of lactide and ϵ‐caprolactone with 2‐hydroxyethyl methacrylate. Both meso‐lactide and L‐lactide were used to produce MMs of various chain lengths and compositions. It was found that properties of generated polymers show a strong dependency both on the content and type of lactide utilized. Standard adhesive tests run on the PSAs demonstrate that MM composition can be used to provide significant control over perfromance properties.
Cardiac R2* values are independent of the image analysis approach employed
Authors: Meloni Antonella , Rienhoff Hugh Young , Jones Amber , Pepe Alessia , Lombardi Massimo , Wood John C. 
Published: October 2013

PurposeTo determine whether systematic differences were present between myocardial R2* values obtained with two different decay models: truncation and exponential + constant (Exp‐C).MethodsSingle‐center cohorts were used to compare black and bright blood sequences separately, and a multicenter cohort of mixed bright and black blood studies was used to assess the generalizability. Truncated exponential estimates were calculated with CMRtools, which uses a single region of interest (ROI) method. Exp‐C estimates were calculated using a pixelwise approach.ResultsNo differences could be distinguished based upon whether a white or black blood sequence was examined. The two fitting algorithms yielded similar R2* values, with R‐squared values exceeding 0.997 and a coefficient of variation of 3% to 4%. Results using the pixelwise method yielded a small systematic bias (∼3%) that became apparent in patients with severe iron deposition. This disparity disappeared when Exp‐C fitting was used on a single ROI, suggesting that the use of pixelwise mapping was responsible for the bias. In the multicenter cohort, the strong agreement between the two fitting approaches was reconfirmed.ConclusionCardiac R2* values are independent of the signal model used for its calculation over clinically relevant ranges. Clinicians can compare results among centers using these disparate approaches with confidence. Magn Reson Med 72:485–491, 2014. © 2013 Wiley Periodicals, Inc.
On the confounding effect of temperature on chemical shift‐encoded fat quantification
Authors: Hernando Diego , Sharma Samir D. , Kramer Harald , Reeder Scott B. 
Published: October 2013

PurposeTo characterize the confounding effect of temperature on chemical shift‐encoded (CSE) fat quantification.MethodsThe proton resonance frequency of water, unlike triglycerides, depends on temperature. This leads to a temperature dependence of the spectral models of fat (relative to water) that are commonly used by CSE‐MRI methods. Simulation analysis was performed for 1.5 Tesla CSE fat–water signals at various temperatures and echo time combinations. Oil–water phantoms were constructed and scanned at temperatures between 0 and 40°C using spectroscopy and CSE imaging at three echo time combinations. An explanted human liver, rejected for transplantation due to steatosis, was scanned using spectroscopy and CSE imaging. Fat–water reconstructions were performed using four different techniques: magnitude and complex fitting, with standard or temperature‐corrected signal modeling.ResultsIn all experiments, magnitude fitting with standard signal modeling resulted in large fat quantification errors. Errors were largest for echo time combinations near TEinit ≈ 1.3 ms, ΔTE ≈ 2.2 ms. Errors in fat quantification caused by temperature‐related frequency shifts were smaller with complex fitting, and were avoided using a temperature‐corrected signal model.ConclusionTemperature is a confounding factor for fat quantification. If not accounted for, it can result in large errors in fat quantifications in phantom and ex vivo acquisitions. Magn Reson Med 72:464–470, 2014. © 2013 Wiley Periodicals, Inc.
Noninvasive imaging of infection after treatment with tumor‐homing bacteria using Chemical Exchange Saturation Transfer (CEST) MRI
Authors: Liu Guanshu , Bettegowda Chetan , Qiao Yuan , Staedtke Verena , Chan Kannie W.Y. , Bai Renyuan , Li Yuguo , Riggins Gregory J. , Kinzler Kenneth W. , Bulte Jeff W.M. , McMahon Michael T. , Gilad Assaf A. , Vogelstein Bert , Zhou Shibin , van Zijl Peter C.M. 
Published: October 2013

PurposeTo develop a noninvasive MRI method for determining the germination and infection of tumor‐homing bacteria in bacteriolytic cancer therapy using endogenous CEST contrast.MethodsThe CEST parameters of the anaerobic gram‐positive bacterium Clostridium novyi‐NT (C. novyi‐NT) were first characterized in vitro, then used to detect C. novyi‐NT germination and infection in subcutaneous CT26 colorectal tumor‐bearing mice (n = 6) after injection of 300 million bacterial spores. Lipopolysacharide (LPS) injected mice were used to exclude that the changes of CEST MRI were due to inflammation.ResultsCEST contrast was observed over a broad frequency range for bacterial suspensions in vitro, with the maximum contrast around 2.6 ppm from the water resonance. No signal could be detected for bacterial spores, demonstrating the specificity for germination. In vivo, a significant elevation of CEST contrast was identified in C. novyi‐NT infected tumors as compared to those before bacterial germination and infection (P < 0.05; n = 6). No significant change was observed in tumors with LPS‐induced sterile inflammation (P > 0.05; n = 4).ConclusionEndogenous bacterial CEST contrast (bacCEST) can be used to monitor the germination and proliferation of the therapeutic bacterium C. novyi‐NT without a need for exogenous cell labeling probes. Magn Reson Med 70:1690–1698, 2013. © 2013 Wiley Periodicals, Inc.
Apparent exchange rate imaging in anisotropic systems
Authors: Sønderby Casper K. , Lundell Henrik M. , Søgaard Lise V. , Dyrby Tim B. 
Published: October 2013

PurposeDouble‐wave diffusion experiments offer the possibility of probing correlation between molecular diffusion at multiple time points. It has recently been shown that this technique is capable of measuring the exchange of water across cellular membranes. The aim of this study was to investigate the effect of macroscopic tissue anisotropy on the measurement of the apparent exchange rate (AXR) in multicompartment systems.MethodsAXR data were collected from yeast and perfusion‐fixated brain tissue at high angular resolution on a preclinical imaging system. The AXR was expanded for anisotropic systems by calculating scalar AXR values along the principal directions of the diffusion tensor.ResultsIn yeast, both the AXR and diffusivity were rotational invariant, whereas in fixated brain tissue, the measured AXR was sensitive to the orientation of anisotropic structures. AXR, especially in white matter, was robustly estimated along the first and second principal directions of the diffusion tensor, but increasing noise was seen in the AXR estimates along the third principal direction of the diffusion tensor.ConclusionOur results indicate that tissue anisotropy must be considered for AXR estimates in complex biological systems. Magn Reson Med 72:756–762, 2014. © 2013 Wiley Periodicals, Inc.
Improved quantification of myocardial blood flow using highly constrained back projection reconstruction
Authors: Chen David , Sharif Behzad , Dharmakumar Rohan , Thomson Louise E.J. , Bairey Merz C. Noel , Berman Daniel S. , Li Debiao 
Published: October 2013

PurposeTo improve quantification of myocardial blood flow using a fast T1 mapping technique using highly constrained back projection reconstruction (HYPR)‐accelerated acquisition.MethodsA major source of error in the measurement of myocardial blood flow (MBF) using MRI is the nonlinear relationship between image signal intensity and contrast agent (CA) concentration. HYPR‐accelerated radial acquisition was used to generate pixel‐wise T1 maps with a temporal resolution of one heartbeat. HYPR produces images with a temporal footprint of 40 ms and four images within 188 ms. T1 values were converted into CA concentrations by the known linear relationship between CA concentration and T1. The T1 mapping technique was used to quantify MBF in 10 healthy subjects and compared with MBF found using image signal intensity as well as MBF reported in the literature.ResultsThe MBF measured using the proposed method was more consistent with that previously reported in the literature and was significantly lower (P = 0.002) than that calculated using image signal intensity (1.11 ± 0.27 mL/min/g versus 1.88 ± 0.45 mL/min/g, respectively).ConclusionWe developed a fast T1 mapping method for MBF quantification using radial sampling and HYPR. Further validation is required to determine its clinical value in assessing myocardial perfusion deficit in coronary artery disease. Magn Reson Med 72:749–755, 2014. © 2013 Wiley Periodicals, Inc.
Viscous energy loss in the presence of abnormal aortic flow
Authors: Barker Alex J. , van Ooij Pim , Bandi Krishna , Garcia Julio , Albaghdadi Mazen , McCarthy Patrick , Bonow Robert O. , Carr James , Collins Jeremy , Malaisrie S. Chris , Markl Michael 
Published: October 2013

PurposeTo present a theoretical basis for noninvasively characterizing in vivo fluid‐mechanical energy losses and to apply it in a pilot study of patients known to express abnormal aortic flow patterns.MethodsFour‐dimensional flow MRI was used to characterize laminar viscous energy losses in the aorta of normal controls (n = 12, age = 37 ± 10 yr), patients with aortic dilation (n = 16, age = 52 ± 8 yr), and patients with aortic valve stenosis matched for age and aortic size (n = 14, age = 46 ± 15 yr), using a relationship between the three‐dimensional velocity field and viscous energy dissipation.ResultsViscous energy loss was elevated significantly in the thoracic aorta in patients with dilated aorta (3.6 ± 1.3 mW, P = 0.024) and patients with aortic stenosis (14.3 ± 8.2 mW, P < 0.001) compared with healthy volunteers (2.3 ± 0.9 mW). The same pattern of significant differences was seen in the ascending aorta, where viscous energy losses in patients with dilated aortas (2.2 ± 1.1 mW, P = 0.021) and patients with aortic stenosis (10.9 ± 6.8 mW, P < 0.001) were elevated compared with healthy volunteers (1.2 ± 0.6 mW).ConclusionThis technique provides a capability to quantify the contribution of abnormal laminar blood flow to increased ventricular afterload. In this pilot study, viscous energy loss in patient cohorts was significantly elevated and indicates that cardiac afterload is increased due to abnormal flow. Magn Reson Med 72:620–628, 2014. © 2013 Wiley Periodicals, Inc.
Localized spatio‐temporal constraints for accelerated CMR perfusion
Authors: Akçakaya Mehmet , Basha Tamer A. , Pflugi Silvio , Foppa Murilo , Kissinger Kraig V. , Hauser Thomas H. , Nezafat Reza 
Published: October 2013

PurposeTo develop and evaluate an image reconstruction technique for cardiac MRI (CMR) perfusion that uses localized spatio‐temporal constraints.MethodsCMR perfusion plays an important role in detecting myocardial ischemia in patients with coronary artery disease. Breath‐hold k‐t–based image acceleration techniques are typically used in CMR perfusion for superior spatial/temporal resolution and improved coverage. In this study, we propose a novel compressed sensing‐based image reconstruction technique for CMR perfusion, with applicability to free‐breathing examinations. This technique uses local spatio‐temporal constraints by regularizing image patches across a small number of dynamics. The technique was compared with conventional dynamic‐by‐dynamic reconstruction, and sparsity regularization using a temporal principal‐component (pc) basis, as well as zero‐filled data in multislice two‐dimensional (2D) and three‐dimensional (3D) CMR perfusion. Qualitative image scores were used (1 = poor, 4 = excellent) to evaluate the technique in 3D perfusion in 10 patients and five healthy subjects. On four healthy subjects, the proposed technique was also compared with a breath‐hold multislice 2D acquisition with parallel imaging in terms of signal intensity curves.ResultsThe proposed technique produced images that were superior in terms of spatial and temporal blurring compared with the other techniques, even in free‐breathing datasets. The image scores indicated a significant improvement compared with other techniques in 3D perfusion (x‐pc regularization, 2.8 ± 0.5 versus 2.3 ± 0.5; dynamic‐by‐dynamic, 1.7 ± 0.5; zero‐filled, 1.1 ± 0.2). Signal intensity curves indicate similar dynamics of uptake between the proposed method with 3D acquisition and the breath‐hold multislice 2D acquisition with parallel imaging.ConclusionThe proposed reconstruction uses sparsity regularization based on localized information in both spatial and temporal domains for highly accelerated CMR perfusion with potential use in free‐breathing 3D acquisitions. Magn Reson Med 72:629–639, 2014. © 2013 Wiley Periodicals, Inc.
Leg muscle function and fatigue during walking in spinal muscular atrophy type 3
Authors: Montes Jacqueline , Dunaway Sally , Garber Carol Ewing , Chiriboga Claudia A. , De Vivo Darryl C. , Rao Ashwini K. 
Published: October 2013

ABSTRACTIntroduction: Spinal muscular atrophy (SMA) causes muscle weakness and fatigue. Better understanding of the relationship between weakness and fatigue may help identify potential targets for rehabilitation. Methods: Gait and surface electromyography (EMG) from 4 muscle groups were measured during the Six‐Minute Walk Test (6MWT) in 10 ambulatory participants, aged 9–49 years. Average root mean square amplitude (RMS) of muscle activity was calculated. Strength was assessed using manual and quantitative methods. Results: RMS, stride length, and velocity decreased during the 6MWT. Knee flexor and hip abductor strength was associated with fatigue‐related changes; overall strength correlated with disease duration; and leg strength was associated with 6MWT distance. Conclusions: Clinical measures are valid in assessing fatigue and function in SMA, and these assessments can be enhanced by use of gait analysis and EMG. Disease duration and strength measures may represent further stratification refinements when enrolling patients in clinical trials. Muscle Nerve 50: 34–39, 2014
Anconeus motor unit number estimates using decomposition‐based quantitative electromyography
Authors: Stevens Daniel E.S. , Harwood Brad , Power Geoffrey A. , Doherty Timothy J. , Rice Charles L. 
Published: October 2013

ABSTRACTIntroduction: Motor unit number estimates (MUNEs) provide important information in health, aging, and disease, and can be determined using decomposition‐enhanced spike‐triggered averaging (DE‐STA). Discrimination of surface‐detected motor unit potentials (S‐MUPs) has been limited to contractile forces of ∽30% maximum voluntary contraction (MVC), which is insufficient to recruit a representative sample of the entire MU pool in most muscles. Unique features of the anconeus may permit MUNEs at high muscle activation levels. Methods: In 10 men (25 ± 3 years), anconeus MUNEs were performed using DE‐STA at 10%, 30%, and 50% root‐mean‐square of MVC (RMSMVC). Results: The mean compound muscle action potential of the anconeus was ∽6 mV, and average S‐MUP amplitudes were ∽100 μV, 145 μV, and 235 μV at 10%, 30%, and 50% RMSMVC, resulting in low average MUNEs of 58, 38, and 25, respectively. Conclusions: Elbow extensor force–EMG relationships suggest full recruitment of the anconeus MU pool at 50% RMSMVC, thus providing a representative sample for MUNE. Muscle Nerve 50: 52–59, 2014