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Sample records for model t1 gem-t1

  1. The combination of satellite and topographic/isostatic potential models for mean anomaly determinations

    Science.gov (United States)

    Rapp, Richard H.; Pavlis, Nikolaos

    A method is presented for the estimation of a global gravity anomaly field using the combination of satellite-derived potential coefficient models and the coefficients implied by the Airy-Heiskanen topographic/isostatic potential (Rummel et al., 1988) from topographic models with a 30-km depth of compensation. Gravity anomalies calculated with this method are compared with a terrestrial 1 x 1 degree anomaly file where the anomaly standard deviations were less than 10 mgals. Using the GEM T1 model (Marsh et al., 1988) to degree 36, the rms anomaly discrepency was + or - 19 mgals, while the rms values for the terrestrial anomalies was + or - 28 mgals.

  2. Disappearing "T1 black holes" in an animal model of multiple sclerosis.

    Science.gov (United States)

    Pirko, Istvan; Johnson, Aaron; Gamez, Jeff; Macura, Slobodan I; Rodriguez, Moses

    2004-05-01

    Brain MRI in multiple sclerosis (MS) frequently shows areas of hypointensity in the white matter on T1 weighted sequences ("T1 black holes"). These areas are thought to be consistent with irreversible axonal loss. In this study T1 black holes were characterized in Theiler's Murine Encephalitis Virus infection, an established model of demyelinating diseases in mice. The spectrum of TMEV is broad in different strains. C57BL/6J mice develop a self-limited brain disease, which resolves within 4-6 weeks. We followed six mice with serial MRI and MRS on days 0, 3,7,21 and 45. The studies were performed in a 7 Tesla magnet. Periventricular and parahippocampal T1 black holes seen as early as 3 days, with decreasing NAA/Cre ratio on MRS. The extent of pathology was most severe on days 3 and 7. T1 black holes are thought to be consistent with areas of irreversible axonal loss. This is challenged by our observations of resolution of T1 black holes by day 45. This was concomitant with the normalization of MRS findings in the areas of interest. We conclude that T1 black holes may represent a transient phenomenon in this model of MS. The recovery of these areas studied suggests an active repair mechanism.

  3. Deformations of $T^{1,1}$ as Yang-Baxter sigma models

    CERN Document Server

    Crichigno, P Marcos; Yoshida, Kentaroh

    2014-01-01

    We consider a family of deformations of T^{1,1} in the Yang-Baxter sigma model approach. We first discuss a supercoset description of T^{1,1}, which makes manifest the full symmetry of the space and leads to the standard Sasaki-Einstein metric. Next, we consider three-parameter deformations of T^{1,1} by using classical r-matrices satisfying the classical Yang-Baxter equation (CYBE). The resulting metric and NS-NS two-form agree exactly with the ones obtained via TsT transformations, and contain the Lunin-Maldacena background as a special case. It is worth noting that for AdS_5 x T^{1,1}, classical integrability for the full sector has been argued to be lost. Hence our result indicates that the Yang-Baxter sigma model approach is applicable even for non-integrable cosets. This observation suggests that the gravity/CYBE correspondence can be extended beyond integrable cases.

  4. Deformations of T 1 ,1 as Yang-Baxter sigma models

    Science.gov (United States)

    Crichigno, P. Marcos; Matsumoto, Takuya; Yoshida, Kentaroh

    2014-12-01

    We consider a family of deformations of T 1,1 in the Yang-Baxter sigma model approach. We first discuss a supercoset description of T 1,1, which makes manifest the full symmetry of the space and leads to the standard Sasaki-Einstein metric. Next, we consider three-parameter deformations of T 1,1 by using classical r-matrices satisfying the classical Yang-Baxter equation (CYBE). The resulting metric and NS-NS two-form agree exactly with the ones obtained via TsT transformations, and contain the Lunin-Maldacena background as a special case. It is worth noting that for AdS5 × T 1,1 , classical integrability for the full sector has been argued to be lost. Hence our result indicates that the Yang-Baxter sigma model approach is applicable even for non-integrable cosets. This observation suggests that the gravity/CYBE correspondence can be extended beyond integrable cases.

  5. Prostate cancer detection from model-free T1-weighted time series and diffusion imaging

    Science.gov (United States)

    Haq, Nandinee F.; Kozlowski, Piotr; Jones, Edward C.; Chang, Silvia D.; Goldenberg, S. Larry; Moradi, Mehdi

    2015-03-01

    The combination of Dynamic Contrast Enhanced (DCE) images with diffusion MRI has shown great potential in prostate cancer detection. The parameterization of DCE images to generate cancer markers is traditionally performed based on pharmacokinetic modeling. However, pharmacokinetic models make simplistic assumptions about the tissue perfusion process, require the knowledge of contrast agent concentration in a major artery, and the modeling process is sensitive to noise and fitting instabilities. We address this issue by extracting features directly from the DCE T1-weighted time course without modeling. In this work, we employed a set of data-driven features generated by mapping the DCE T1 time course to its principal component space, along with diffusion MRI features to detect prostate cancer. The optimal set of DCE features is extracted with sparse regularized regression through a Least Absolute Shrinkage and Selection Operator (LASSO) model. We show that when our proposed features are used within the multiparametric MRI protocol to replace the pharmacokinetic parameters, the area under ROC curve is 0.91 for peripheral zone classification and 0.87 for whole gland classification. We were able to correctly classify 32 out of 35 peripheral tumor areas identified in the data when the proposed features were used with support vector machine classification. The proposed feature set was used to generate cancer likelihood maps for the prostate gland.

  6. Myocardial T1 maps reflect histological findings in acute and chronic stages of myocarditis in a rat model

    DEFF Research Database (Denmark)

    Jeuthe, Sarah; Wassilew, Katharina; O H-Ici, Darach;

    2016-01-01

    BACKGROUND: Cardiovascular magnetic resonance offers both diagnostic and prognostic information in myocarditis. Using an established animal model of myocarditis, the aim of this study was to measure myocardial T1 before the onset, in the acute and in the chronic phases of the disease and to compare...... conventional histology (HE and Sirius-Red staining) and immunohistochemistry (CD 68) investigations. RESULTS: All immunized rats developed myocarditis (morbidity 100%). Histologically we observed increased wall thickness with biventricular macrophage-rich mixed inflammatory infiltrates. All rats...... with a histologically severe myocarditis showed increased native T1 and decreased post-contrast T1 of the myocardium. CONCLUSIONS: The assessment of native T1 and post-contrast T1 allows accurate differentiation between healthy myocardium and myocardium with inflammation and also between the acute and chronic phases...

  7. Piperine suppresses tumor growth and metastasis in vitro and in vivo in a 4T1 murine breast cancer model

    Institute of Scientific and Technical Information of China (English)

    Li-hua LAI; Qi-hong FU; Yang LIU; Kai JIANG; Qing-ming GUO; Qing-yun CHEN; Bin YAN; Qing-qing WANG; Jian-gen SHEN

    2012-01-01

    Aim:To investigate the effects of piperine,a major pungent alkaloid present in Piper nigrum and Piper Iongum,on the tumor growth and metastasis of mouse 4T1 mammary carcinoma in vitro and in vivo,and elucidate the underlying mechanisms.Methods:Growth of 4T1 cells was assessed using MTT assay.Apoptosis and cell cycle of 4T1 cells were evaluated with flow cytometry,and the related proteins were examined using Western blotting.Real-time quantitative PCR was applied to detect the expression of matrix metalloproteinases (MMPs).A highly malignant,spontaneously metastasizing 4T1 mouse mammary carcinoma model was used to evaluate the in vivo antitumor activity.Piperine was injected into tumors every 3 d for 3 times.Results:Piperine (35-280 μmol/L)inhibited the growth of 4T1 cells in time-and dose-dependent manners (the IC50 values were 105+1.08 and 78.52+1.06 μmol/L,respectively,at 48 and 72 h).Treatment of 4T1 cells with piperine (70-280 μmol/L)dose-dependently induced apoptosis of 4T1 cells,accompanying activation of caspase 3.The cells treated with piperine (140 and 280μmol/L)significantly increased the percentage of cells in G2/M phase with a reduction in the expression of cyclin B1.Piperine (140and 280 μmol/L)significantly decreased the expression of MMP-9 and MMP-13,and inhibited 4T1 cell migration in vitro.Injection of piperine (2.5 and 5 mg/kg)dose-dependently suppressed the primary 4T1 tumor growth and injection of piperine (5 mg/kg)significantly inhibited the lung metastasis.Conclusion:These results demonstrated that piperine is an effective antitumor compound in vitro and in vivo,and has the potential to be developed as a new anticancer drug.

  8. Regional contrast agent quantification in a mouse model of myocardial infarction using 3D cardiac T1 mapping

    Directory of Open Access Journals (Sweden)

    Nicolay Klaas

    2011-10-01

    Full Text Available Abstract Background Quantitative relaxation time measurements by cardiovascular magnetic resonance (CMR are of paramount importance in contrast-enhanced studies of experimental myocardial infarction. First, compared to qualitative measurements based on signal intensity changes, they are less sensitive to specific parameter choices, thereby allowing for better comparison between different studies or during longitudinal studies. Secondly, T1 measurements may allow for quantification of local contrast agent concentrations. In this study, a recently developed 3D T1 mapping technique was applied in a mouse model of myocardial infarction to measure differences in myocardial T1 before and after injection of a liposomal contrast agent. This was then used to assess the concentration of accumulated contrast agent. Materials and methods Myocardial ischemia/reperfusion injury was induced in 8 mice by transient ligation of the LAD coronary artery. Baseline quantitative T1 maps were made at day 1 after surgery, followed by injection of a Gd-based liposomal contrast agent. Five mice served as control group, which followed the same protocol without initial surgery. Twenty-four hours post-injection, a second T1 measurement was performed. Local ΔR1 values were compared with regional wall thickening determined by functional cine CMR and correlated to ex vivo Gd concentrations determined by ICP-MS. Results Compared to control values, pre-contrast T1 of infarcted myocardium was slightly elevated, whereas T1 of remote myocardium did not significantly differ. Twenty-four hours post-contrast injection, high ΔR1 values were found in regions with low wall thickening values. However, compared to remote tissue (wall thickening > 45%, ΔR1 was only significantly higher in severe infarcted tissue (wall thickening r = 0.81 was found between CMR-based ΔR1 values and Gd concentrations from ex vivo ICP-MS measurements. Furthermore, regression analysis revealed that the

  9. A general model to calculate the spin-lattice (T1) relaxation time of blood, accounting for haematocrit, oxygen saturation and magnetic field strength.

    Science.gov (United States)

    Hales, Patrick W; Kirkham, Fenella J; Clark, Christopher A

    2016-02-01

    Many MRI techniques require prior knowledge of the T1-relaxation time of blood (T1bl). An assumed/fixed value is often used; however, T1bl is sensitive to magnetic field (B0), haematocrit (Hct), and oxygen saturation (Y). We aimed to combine data from previous in vitro measurements into a mathematical model, to estimate T1bl as a function of B0, Hct, and Y. The model was shown to predict T1bl from in vivo studies with a good accuracy (± 87 ms). This model allows for improved estimation of T1bl between 1.5-7.0 T while accounting for variations in Hct and Y, leading to improved accuracy of MRI-derived perfusion measurements.

  10. Final Report - IHLW PCT, Spinel T1%, Electrical Conductivity, and Viscosity Model Development, VSL-07R1240-4

    Energy Technology Data Exchange (ETDEWEB)

    Kruger, Albert A.; Piepel, Gregory F.; Landmesser, S. M.; Pegg, I. L.; Heredia-Langner, Alejandro; Cooley, Scott K.; Gan, H.; Kot, W. K.

    2013-11-13

    This report is the last in a series of currently scheduled reports that presents the results from the High Level Waste (HLW) glass formulation development and testing work performed at the Vitreous State Laboratory (VSL) of the Catholic University of America (CUA) and the development of IHLW property-composition models performed jointly by Pacific Northwest National Laboratory (PNNL) and VSL for the River Protection Project-Waste Treatment and Immobilization Plant (RPP-WTP). Specifically, this report presents results of glass testing at VSL and model development at PNNL for Product Consistency Test (PCT), one-percent crystal fraction temperature (T1%), electrical conductivity (EC), and viscosity of HLW glasses. The models presented in this report may be augmented and additional validation work performed during any future immobilized HLW (IHLW) model development work. Completion of the test objectives is addressed.

  11. Systematized Water content Calculation in Cartilage Using T1-mapping MR Estimations. Design of a Mathematical Model

    DEFF Research Database (Denmark)

    Shiguetomi Medina, Juan Manuel; Ramirez Garcia-Luna, Jose Luis; Rahbek, Ole

    .5 Tesla by calculating absolute T1 values in real maps through inverse angle phase inverse sequence recuperation (11 inversion times, from 200 to 2200 msec) at 37(±0.5) °C. Regions of interest were manually delineated and the mean T1 value was estimated using a T1-map analysis software. The collected data...

  12. Thalamic nuclei segmentation in clinical 3T T1-weighted Images using high-resolution 7T shape models

    Science.gov (United States)

    Liu, Yuan; D'Haese, Pierre-François; Newton, Allen T.; Dawant, Benoit M.

    2015-03-01

    Accurate and reliable identification of thalamic nuclei is important for surgical interventions and neuroanatomical studies. This is a challenging task due to their small sizes and low intra-thalamic contrast in standard T1-weighted or T2- weighted images. Previously proposed techniques rely on diffusion imaging or functional imaging. These require additional scanning and suffer from the low resolution and signal-to-noise ratio in these images. In this paper, we aim to directly segment the thalamic nuclei in standard 3T T1-weighted images using shape models. We manually delineate the structures in high-field MR images and build high resolution shape models from a group of subjects. We then investigate if the nuclei locations can be inferred from the whole thalamus. To do this, we hierarchically fit joint models. We start from the entire thalamus and fit a model that captures the relation between the thalamus and large nuclei groups. This allows us to infer the boundaries of these nuclei groups and we repeat the process until all nuclei are segmented. We validate our method in a leave-one-out fashion with seven subjects by comparing the shape-based segmentations on 3T images to the manual contours. Results we have obtained for major nuclei (dice coefficients ranging from 0.57 to 0.88 and mean surface errors from 0.29mm to 0.72mm) suggest the feasibility of using such joint shape models for localization. This may have a direct impact on surgeries such as Deep Brain Stimulation procedures that require the implantation of stimulating electrodes in specific thalamic nuclei.

  13. Contrasting roles for CD4 vs. CD8 T-cells in a murine model of virally induced "T1 black hole" formation.

    Directory of Open Access Journals (Sweden)

    Istvan Pirko

    Full Text Available MRI is sensitive to tissue pathology in multiple sclerosis (MS; however, most lesional MRI findings have limited correlation with disability. Chronic T1 hypointense lesions or "T1 black holes" (T1BH, observed in a subset of MS patients and thought to represent axonal damage, show moderate to strong correlation with disability. The pathogenesis of T1BH remains unclear. We previously reported the first and as of yet only model of T1BH formation in the Theiler's murine encephalitis virus induced model of acute CNS neuroinflammation induced injury, where CD8 T-cells are critical mediators of axonal damage and related T1BH formation. The purpose of this study was to further analyze the role of CD8 and CD4 T-cells through adoptive transfer experiments and to determine if the relevant CD8 T-cells are classic epitope specific lymphocytes or different subsets. C57BL/6 mice were used as donors and RAG-1 deficient mice as hosts in our adoptive transfer experiments. In vivo 3-dimensional MRI images were acquired using a 7 Tesla small animal MRI system. For image analysis, we used semi-automated methods in Analyze 9.1; transfer efficiency was monitored using FACS of brain infiltrating lymphocytes. Using a peptide depletion method, we demonstrated that the majority of CD8 T-cells are classic epitope specific cytotoxic cells. CD8 T-cell transfer successfully restored the immune system's capability to mediate T1BH formation in animals that lack adaptive immune system, whereas CD4 T-cell transfer results in an attenuated phenotype with significantly less T1BH formation. These findings demonstrate contrasting roles for these cell types, with additional evidence for a direct pathogenic role of CD8 T-cells in our model of T1 black hole formation.

  14. Contrasting roles for CD4 vs. CD8 T-cells in a murine model of virally induced "T1 black hole" formation.

    Science.gov (United States)

    Pirko, Istvan; Chen, Yi; Lohrey, Anne K; McDole, Jeremiah; Gamez, Jeffrey D; Allen, Kathleen S; Pavelko, Kevin D; Lindquist, Diana M; Dunn, R Scott; Macura, Slobodan I; Johnson, Aaron J

    2012-01-01

    MRI is sensitive to tissue pathology in multiple sclerosis (MS); however, most lesional MRI findings have limited correlation with disability. Chronic T1 hypointense lesions or "T1 black holes" (T1BH), observed in a subset of MS patients and thought to represent axonal damage, show moderate to strong correlation with disability. The pathogenesis of T1BH remains unclear. We previously reported the first and as of yet only model of T1BH formation in the Theiler's murine encephalitis virus induced model of acute CNS neuroinflammation induced injury, where CD8 T-cells are critical mediators of axonal damage and related T1BH formation. The purpose of this study was to further analyze the role of CD8 and CD4 T-cells through adoptive transfer experiments and to determine if the relevant CD8 T-cells are classic epitope specific lymphocytes or different subsets. C57BL/6 mice were used as donors and RAG-1 deficient mice as hosts in our adoptive transfer experiments. In vivo 3-dimensional MRI images were acquired using a 7 Tesla small animal MRI system. For image analysis, we used semi-automated methods in Analyze 9.1; transfer efficiency was monitored using FACS of brain infiltrating lymphocytes. Using a peptide depletion method, we demonstrated that the majority of CD8 T-cells are classic epitope specific cytotoxic cells. CD8 T-cell transfer successfully restored the immune system's capability to mediate T1BH formation in animals that lack adaptive immune system, whereas CD4 T-cell transfer results in an attenuated phenotype with significantly less T1BH formation. These findings demonstrate contrasting roles for these cell types, with additional evidence for a direct pathogenic role of CD8 T-cells in our model of T1 black hole formation.

  15. Optimizing non-invasive radiofrequency hyperthermia treatment for improving drug delivery in 4T1 mouse breast cancer model

    Science.gov (United States)

    Ware, Matthew J.; Krzykawska-Serda, Martyna; Chak-Shing Ho, Jason; Newton, Jared; Suki, Sarah; Law, Justin; Nguyen, Lam; Keshishian, Vazrik; Serda, Maciej; Taylor, Kimberly; Curley, Steven A.; Corr, Stuart J.

    2017-03-01

    Interactions of high-frequency radio waves (RF) with biological tissues are currently being investigated as a therapeutic platform for non-invasive cancer hyperthermia therapy. RF delivers thermal energy into tissues, which increases intra-tumoral drug perfusion and blood-flow. Herein, we describe an optical-based method to optimize the short-term treatment schedules of drug and hyperthermia administration in a 4T1 breast cancer model via RF, with the aim of maximizing drug localization and homogenous distribution within the tumor microenvironment. This method, based on the analysis of fluorescent dyes localized into the tumor, is more time, cost and resource efficient, when compared to current analytical methods for tumor-targeting drug analysis such as HPLC and LC-MS. Alexa-Albumin 647 nm fluorphore was chosen as a surrogate for nab-paclitaxel based on its similar molecular weight and albumin driven pharmacokinetics. We found that RF hyperthermia induced a 30–40% increase in Alexa-Albumin into the tumor micro-environment 24 h after treatment when compared to non-heat treated mice. Additionally, we showed that the RF method of delivering hyperthermia to tumors was more localized and uniform across the tumor mass when compared to other methods of heating. Lastly, we provided insight into some of the factors that influence the delivery of RF hyperthermia to tumors.

  16. In vivo relaxation time measurements on a murine tumor model--prolongation of T1 after photodynamic therapy.

    Science.gov (United States)

    Liu, Y H; Hawk, R M; Ramaprasad, S

    1995-01-01

    RIF tumors implanted on mice feet were investigated for changes in relaxation times (T1 and T2) after photodynamic therapy (PDT). Photodynamic therapy was performed using Photofrin II as the photosensitizer and laser light at 630 nm. A home-built proton solenoid coil in the balanced configuration was used to accommodate the tumors, and the relaxation times were measured before, immediately after, and up to several hours after therapy. Several control experiments were performed untreated tumors, tumors treated with Photofrin II alone, or tumors treated with laser light alone. Significant increases in T1s of water protons were observed after PDT treatment. In all experiments, 31P spectra were recorded before and after the therapy to study the tumor status and to confirm the onset of PDT. These studies show significant prolongation of T1s after the PDT treatment. The spin-spin relaxation measurements, on the other hand, did not show such prolongation in T2 values after PDT treatment.

  17. Dipeptide model prodrugs for the intestinal oligopeptide transporter. Affinity for and transport via hPepT1 in the human intestinal Caco-2 cell line

    DEFF Research Database (Denmark)

    Nielsen, C U; Andersen, R; Brodin, Birger

    2001-01-01

    The human intestinal di/tri-peptide carrier, hPepT1, has been suggested as a drug delivery target via increasing the intestinal transport of low permeability compounds by designing peptidomimetic prodrugs. Model ester prodrugs using the stabilized dipeptides D-Glu-Ala and D-Asp-Ala as pro......-moieties for benzyl alcohol have been shown to maintain affinity for hPepT1. The primary aim of the present study was to investigate if modifications of the benzyl alcohol model drug influence the corresponding D-Glu-Ala and D-Asp-Ala model prodrugs' affinity for hPepT1 in Caco-2 cells. A second aim...... was to investigate the transepithelial transport and hydrolysis parameters for D-Asp(BnO)-Ala and D-Glu(BnO)-Ala across Caco-2 cell monolayers. In the present study, all investigated D-Asp-Ala and D-Glu-Ala model prodrugs retained various degrees of affinity for hPepT1 in Caco-2 cells. These affinities are used...

  18. Electrical characterization and modeling of 1T-1R RRAM arrays with amorphous and poly-crystalline HfO2

    Science.gov (United States)

    Grossi, Alessandro; Zambelli, Cristian; Olivo, Piero; Crespo-Yepes, Alberto; Martin-Martinez, Javier; Rodríguez, Rosana; Nafria, Monserrat; Perez, Eduardo; Wenger, Christian

    2017-02-01

    In this work, a comparison between 1T-1R RRAM arrays, manufactured either with amorphous or poly-crystalline Metal-Insulator-Metal cells, is reported in terms of performance, reliability, Set/Reset operations energy requirements, intra-cell and inter-cell variability during 10k endurance cycles and 100k read disturb cycles. The modeling of the 1T-1R RRAM array cells has been performed with two different approaches: (i) a physical model like the Quantum Point Contact (QPC) model was used to find the relationship between the reliability properties observed during the endurance and the read disturb tests with the conductive filament properties; (ii) a compact model to be exploited in circuit simulations tools which models the I-V characteristics of each memory cells technology.

  19. Deletion of the BDNF truncated receptor TrkB.T1 delays disease onset in a mouse model of amyotrophic lateral sclerosis.

    Directory of Open Access Journals (Sweden)

    Sudhirkumar U Yanpallewar

    Full Text Available Brain Derived Neurotrophic Factor (BDNF exerts strong pro-survival effects on developing and injured motoneurons. However, in clinical trials, BDNF has failed to benefit patients with amyotrophic lateral sclerosis (ALS. To date, the cause of this failure remains unclear. Motoneurons express the TrkB kinase receptor but also high levels of the truncated TrkB.T1 receptor isoform. Thus, we investigated whether the presence of this receptor may affect the response of diseased motoneurons to endogenous BDNF. We deleted TrkB.T1 in the hSOD1(G93A ALS mouse model and evaluated the impact of this mutation on motoneuron death, muscle weakness and disease progression. We found that TrkB.T1 deletion significantly slowed the onset of motor neuron degeneration. Moreover, it delayed the development of muscle weakness by 33 days. Although the life span of the animals was not affected we observed an overall improvement in the neurological score at the late stage of the disease. To investigate the effectiveness of strategies aimed at bypassing the TrkB.T1 limit to BDNF signaling we treated SOD1 mutant mice with the adenosine A2A receptor agonist CGS21680, which can activate motoneuron TrkB receptor signaling independent of neurotrophins. We found that CGS21680 treatment slowed the onset of motor neuron degeneration and muscle weakness similarly to TrkB.T1 removal. Together, our data provide evidence that endogenous TrkB.T1 limits motoneuron responsiveness to BDNF in vivo and suggest that new strategies such as Trk receptor transactivation may be used for therapeutic intervention in ALS or other neurodegenerative disorders.

  20. The immunostimulatory effect of biogenic selenium nanoparticles on the 4T1 breast cancer model: an in vivo study.

    Science.gov (United States)

    Yazdi, Mohammad Hossein; Mahdavi, Mehdi; Varastehmoradi, Bardia; Faramarzi, Mohammad Ali; Shahverdi, Ahmad Reza

    2012-10-01

    Selenium salts as well as elemental selenium nanoparticles are attracting the attention of researchers due to their excellent biological properties. The aim of the present work was to study immunomodulation by applying elemental Se NPs to stimulate the immune response of mice bearing 4 T1 breast cancer tumors. Six- to 8-week-old female inbred BALB/c mice were divided into two groups of test and control, each containing 15 mice. Every day, for 2 weeks prior to tumor induction, selenium nanoparticles were orally administered to the mice at a dose of 100 μg/day. Then, 1 × 10(6) cells from a 4 T1 cell line were injected subcutaneously to each mouse. Oral nanoparticle administration was continued daily for 3 weeks after tumor induction. Different immunological parameters were then evaluated including cytokine level, delayed type hypersensitivity (DTH) response as well as tumor growth and the survival rates in all treated or nontreated animals. The production of Th1 cytokines, such as IFN-γ and IL-12, in spleen cell culture was increased in the test mice-administered selenium nanoparticles. The DTH response of test mice also showed a significant increase when compared to the control mice. The survival rate was notably higher for the selenium nanoparticle-treated mice compared to the control mice. Our results suggest that selenium nanoparticle administration can result in considerable induction of the Th1 platform of immune response through the elevation of IFN-γ and IL-12 and may be a cause for better prognosis in mice with tumors.

  1. Yang-Baxter deformations of W2,4 × T1,1 and the associated T-dual models

    Science.gov (United States)

    Sakamoto, Jun-ichi; Yoshida, Kentaroh

    2017-08-01

    Recently, for principal chiral models and symmetric coset sigma models, Hoare and Tseytlin proposed an interesting conjecture that the Yang-Baxter deformations with the homogeneous classical Yang-Baxter equation are equivalent to non-abelian T-dualities with topological terms. It is significant to examine this conjecture for non-symmetric (i.e., non-integrable) cases. Such an example is the W2,4 ×T 1 , 1 background. In this note, we study Yang-Baxter deformations of type IIB string theory defined on W2,4 ×T 1 , 1 and the associated T-dual models, and show that this conjecture is valid even for this case. Our result indicates that the conjecture would be valid beyond integrability.

  2. Comparison and validation of tissue modelization and statistical classification methods in T1-weighted MR brain images.

    Science.gov (United States)

    Cuadra, Meritxell Bach; Cammoun, Leila; Butz, Torsten; Cuisenaire, Olivier; Thiran, Jean-Philippe

    2005-12-01

    This paper presents a validation study on statistical nonsupervised brain tissue classification techniques in magnetic resonance (MR) images. Several image models assuming different hypotheses regarding the intensity distribution model, the spatial model and the number of classes are assessed. The methods are tested on simulated data for which the classification ground truth is known. Different noise and intensity nonuniformities are added to simulate real imaging conditions. No enhancement of the image quality is considered either before or during the classification process. This way, the accuracy of the methods and their robustness against image artifacts are tested. Classification is also performed on real data where a quantitative validation compares the methods' results with an estimated ground truth from manual segmentations by experts. Validity of the various classification methods in the labeling of the image as well as in the tissue volume is estimated with different local and global measures. Results demonstrate that methods relying on both intensity and spatial information are more robust to noise and field inhomogeneities. We also demonstrate that partial volume is not perfectly modeled, even though methods that account for mixture classes outperform methods that only consider pure Gaussian classes. Finally, we show that simulated data results can also be extended to real data.

  3. New limits on Beyond Standard Model physics from a measurement of the half-life of the T=1/2 mirror decay of 19Ne

    CERN Document Server

    Broussard, L; Boswell, M S; Crowell, A S; Dendooven, P; Howell, C R; Kidd, M F; Jungmann, K; Kruithof, W L; Onderwater, C J G; Pattie, R W; Shidling, P D; Sohani, M; van der Hoek, D J; Rogachevskiy, A; Traykov, E; Versolato, O O; Willmann, L; Wilschut, H W; Young, A R

    2013-01-01

    The 1/2+ -> 1/2+ superallowed mixed mirror decay of 19Ne to 19F is excellently suited for high-precision studies of the weak interaction. However, there is some disagreement on the value of the half-life. In a new measurement we have determined this quantity to be T_{1/2} = 17.2832 +/- 0.0051_{(stat)} +/- 0.0066_{(sys)} seconds, which differs from the previous world average by 3 standard deviations. The impact of this measurement on limits for physics beyond the standard model such as the presence of tensor currents is discussed.

  4. GlyT-1 Inhibition Attenuates Attentional But Not Learning or Motivational Deficits of the Sp4 Hypomorphic Mouse Model Relevant to Psychiatric Disorders.

    Science.gov (United States)

    Young, Jared W; Kamenski, Mary E; Higa, Kerin K; Light, Gregory A; Geyer, Mark A; Zhou, Xianjin

    2015-11-01

    Serious mental illness occurs in 25% of the general population, with many disorders being neurodevelopmental, lifelong, and debilitating. The wide variation and overlap in symptoms across disorders increases the difficulty of research and treatment development. The NIMH Research Domain of Criteria initiative aims to improve our understanding of the molecular and behavioral consequences of specific neurodevelopmental mechanisms across disorders, enabling targeted treatment development. The transcription factor Specificity Protein 4 (SP4) is important for neurodevelopment and is genetically associated with both schizophrenia and bipolar disorder. Reduced Sp4 expression in mice (hypomorphic) reproduces several characteristics of psychiatric disorders. We further tested the utility of Sp4 hypomorphic mice as a model organism relevant to psychiatric disorders by assessing cognitive control plus effort and decision-making aspects of approach motivation using cross-species-relevant tests. Sp4 hypomorphic mice exhibited impaired attention as measured by the 5-Choice Continuous Performance Test, an effect that was attenuated by glycine type-1 transporter (GlyT-1) inhibition. Hypomorphic mice also exhibited reduced motivation to work for a reward and impaired probabilistic learning. These deficits may stem from affected anticipatory reward, analogous to anhedonia in patients with schizophrenia and other psychiatric disorders. Neither positive valence deficit was attenuated by GlyT-1 treatment, suggesting that these and the attentional deficits stem from different underlying mechanisms. Given the association of SP4 gene with schizophrenia and bipolar disorder, the present studies provide support that personalized GlyT-1 inhibition may treat attentional deficits in neuropsychiatric patients with low SP4 levels.

  5. Radio-photothermal therapy mediated by a single compartment nanoplatform depletes tumor initiating cells and reduces lung metastasis in the orthotopic 4T1 breast tumor model

    Science.gov (United States)

    Zhou, Min; Zhao, Jun; Tian, Mei; Song, Shaoli; Zhang, Rui; Gupta, Sanjay; Tan, Dongfeng; Shen, Haifa; Ferrari, Mauro; Li, Chun

    2015-11-01

    Tumor Initiating Cells (TICs) are resistant to radiotherapy and chemotherapy, and are believed to be responsible for tumor recurrence and metastasis. Combination therapies can overcome the limitation of conventional cancer treatments, and have demonstrated promising application in the clinic. Here, we show that dual modality radiotherapy (RT) and photothermal therapy (PTT) mediated by a single compartment nanosystem copper-64-labeled copper sulfide nanoparticles ([64Cu]CuS NPs) could suppress breast tumor metastasis through eradication of TICs. Positron electron tomography (PET) imaging and biodistribution studies showed that more than 90% of [64Cu]CuS NPs was retained in subcutaneously grown BT474 breast tumor 24 h after intratumoral (i.t.) injection, indicating the NPs are suitable for the combination therapy. Combined RT/PTT therapy resulted in significant tumor growth delay in the subcutaneous BT474 breast cancer model. Moreover, RT/PTT treatment significantly prolonged the survival of mice bearing orthotopic 4T1 breast tumors compared to no treatment, RT alone, or PTT alone. The RT/PTT combination therapy significantly reduced the number of tumor nodules in the lung and the formation of tumor mammospheres from treated 4T1 tumors. No obvious side effects of the CuS NPs were noted in the treated mice in a pilot toxicity study. Taken together, our data support the feasibility of a therapeutic approach for the suppression of tumor metastasis through localized RT/PTT therapy.Tumor Initiating Cells (TICs) are resistant to radiotherapy and chemotherapy, and are believed to be responsible for tumor recurrence and metastasis. Combination therapies can overcome the limitation of conventional cancer treatments, and have demonstrated promising application in the clinic. Here, we show that dual modality radiotherapy (RT) and photothermal therapy (PTT) mediated by a single compartment nanosystem copper-64-labeled copper sulfide nanoparticles ([64Cu]CuS NPs) could suppress

  6. GlyT1 Inhibitor NFPS Exerts Neuroprotection via GlyR Alpha1 Subunit in the Rat Model of Transient Focal Cerebral Ischaemia and Reperfusion

    Directory of Open Access Journals (Sweden)

    Baosheng Huang

    2016-05-01

    Full Text Available Background/Aims: Glycine is a strychnine-sensitive inhibitory neurotransmitter in the central nervous system (CNS, especially in the spinal cord, brainstem, and retina. The objective of the present study was to investigate the potential neuroprotective effects of GlyT1 inhibitor N [3-(4'-fluorophenyl-3-(4'-phenylphenoxy propyl] sarcosine (NFPS in the rat model of experimental stroke. Methods: In vivo ischaemia was induced by transient middle cerebral artery occlusion (tMCAO. The methods of Western Blotting, Nissl Staining and Morris water maze methods were applied to analyze the anti-ischaemia mechanism. Results: The results showed that high dose of NFPS (H-NFPS significantly reduced infarct volume, neuronal injury and the expression of cleaved caspase-3, enhanced Bcl-2/Bax, and improved spatial learning deficits which were administered three hours after transient middle cerebral artery occlusion (tMCAO induction in rats, while, low dose of NFPS (L-NFPS exacerbated the injury of ischaemia. These findings suggested that low and high dose of NFPS produced opposite effects. Importantly, it was demonstrated that H-NFPS-dependent neuronal protection was inverted by salicylate (Sal, a specific GlyR ɑ1 antagonist. Such effects could probably be attributed to the enhanced glycine level in both synaptic and extrasynaptic clefts and the subsequently altered extrasynaptic GlyRs and their subtypes. Conclusions: These data imply that GlyT1 inhibitor NFPS may be a novel target for clinical treatment of transient focal cerebral ischaemia and reperfusion which are associated with altered GlyR alpha 1 subunits.

  7. Cancer associated fibroblasts promote tumor growth and metastasis by modulating the tumor immune microenvironment in a 4T1 murine breast cancer model.

    Directory of Open Access Journals (Sweden)

    Debbie Liao

    Full Text Available BACKGROUND: Local inflammation associated with solid tumors commonly results from factors released by tumor cells and the tumor stroma, and promotes tumor progression. Cancer associated fibroblasts comprise a majority of the cells found in tumor stroma and are appealing targets for cancer therapy. Here, our aim was to determine the efficacy of targeting cancer associated fibroblasts for the treatment of metastatic breast cancer. METHODOLOGY/PRINCIPAL FINDINGS: We demonstrate that cancer associated fibroblasts are key modulators of immune polarization in the tumor microenvironment of a 4T1 murine model of metastatic breast cancer. Elimination of cancer associated fibroblasts in vivo by a DNA vaccine targeted to fibroblast activation protein results in a shift of the immune microenvironment from a Th2 to Th1 polarization. This shift is characterized by increased protein expression of IL-2 and IL-7, suppressed recruitment of tumor-associated macrophages, myeloid derived suppressor cells, T regulatory cells, and decreased tumor angiogenesis and lymphangiogenesis. Additionally, the vaccine improved anti-metastatic effects of doxorubicin chemotherapy and enhanced suppression of IL-6 and IL-4 protein expression while increasing recruitment of dendritic cells and CD8(+ T cells. Treatment with the combination therapy also reduced tumor-associated Vegf, Pdgfc, and GM-CSF mRNA and protein expression. CONCLUSIONS/SIGNIFICANCE: Our findings demonstrate that cancer associated fibroblasts promote tumor growth and metastasis through their role as key modulators of immune polarization in the tumor microenvironment and are valid targets for therapy of metastatic breast cancer.

  8. Comparison of the Adipose and Luminal Mammary Gland Compartment as Orthotopic Inoculation Sites in a 4T1-Based Immunocompetent Preclinical Model for Triple-Negative Breast Cancer.

    Science.gov (United States)

    Steenbrugge, Jonas; Breyne, Koen; Denies, Sofie; Dekimpe, Melissa; Demeyere, Kristel; De Wever, Olivier; Vermeulen, Peter; Van Laere, Steven; Sanders, Niek N; Meyer, Evelyne

    2016-12-01

    Breast tumorigenesis is classically studied in mice by inoculating tumor cells in the fat pad, the adipose compartment of the mammary gland. Alternatively, the mammary ducts, which constitute the luminal mammary gland compartment, also provide a suitable inoculation site to induce breast cancer in murine models. The microenvironments in these compartments influence tumor cell progression, yet this effect has not been investigated in an immunocompetent context. Here, we compared both mammary gland compartments as distinct inoculation sites, taking into account the immunological aspect by inoculating 4T1 tumor cells in immunocompetent mice. Following tumor cell inoculation in the adipose compartment of non-pretreated/naive, hormonally pretreated/naive and non-pretreated/lactating mice, the primary tumors developed similarly. However, a slower onset of primary tumor growth was found after inoculations in the luminal compartment of non-pretreated/lactating mice. Despite this difference in tumor development rate, metastasis to the liver and lungs was equally observed and was accompanied by lymphatic spreading of tumor cells and progressive splenomegaly with both inoculation types. Chitinase 3-like 1 (CHI3L1) and lipocalin 2 (LCN2) served as innovative biomarkers for disease progression showing increased levels in primary tumors and sera of the non-pretreated/lactating inoculation groups. A slower increase in circulating CHI3L1 but not LCN2 levels, was observed after inoculations in the luminal compartment which corroborated the slower tumor development at this inoculation site. Our results highlight the critical impact of different mammary gland compartments on tumor development in syngeneic murine models and support the use of novel tumor progression biomarkers in an immune-competent environment.

  9. T(1,1,t+1,t,1)和T(1,1,t+2,t,1)的色唯一性%Chromatic Uniqueness of T(1,1,t+1,t,1)and T(1,1,t+2,t,1)

    Institute of Scientific and Technical Information of China (English)

    毛建树; 刘儒英

    2009-01-01

    In this paper,let h(G,x)denote adjoining polynomial of graph G,and β(G)denote the minimum negative real roots of h(G,,x),we prove that T(1,1,t+1,t,1)andT(1,1,t+2,t,1)with t≥3 are chromatically unique.%h(G,x)表示图G的伴随多项式,β(G)表示h(G,x)的最小负实根.证明了当t≥3时,T(1,1,t+1,t,1)和T(1,1,t+2,t,1)的补图的色唯一性.

  10. Differential Proteome Analysis Identifies TGF-β-Related Pro-Metastatic Proteins in a 4T1 Murine Breast Cancer Model.

    Directory of Open Access Journals (Sweden)

    Misako Sato

    Full Text Available Transforming growth factor-β (TGF-β has a dual role in tumorigenesis, acting as either a tumor suppressor or as a pro-oncogenic factor in a context-dependent manner. Although TGF-β antagonists have been proposed as anti-metastatic therapies for patients with advanced stage cancer, how TGF-β mediates metastasis-promoting effects is poorly understood. Establishment of TGF-β-related protein expression signatures at the metastatic site could provide new mechanistic information and potentially allow identification of novel biomarkers for clinical intervention to discriminate TGF-β oncogenic effects from tumor suppressive effects. In the present study, we found that systemic administration of the TGF-β receptor kinase inhibitor, SB-431542, significantly inhibited lung metastasis from transplanted 4T1 mammary tumors in Balb/c mice. The differentially expressed proteins in the comparison of lung metastases from SB-431542 treated and control vehicle-treated groups were analyzed by a quantitative LTQ Orbitrap Velos system coupled with stable isotope dimethyl labeling. A total of 36,239 peptides from 6,694 proteins were identified, out of which 4,531 proteins were characterized as differentially expressed. A subset of upregulated proteins in the control group was validated by western blotting and immunohistochemistry. The eukaryotic initiation factor (eIF family members constituted the most enriched protein pathway in vehicle-treated compared with SB-43512-treated lung metastases, suggesting that increased protein expression of specific eIF family members, especially eIF4A1 and eEF2, is related to the metastatic phenotype of advanced breast cancer and can be down-regulated by TGF-β pathway inhibitors. Thus our proteomic approach identified eIF pathway proteins as novel potential mediators of TGF-β tumor-promoting activity.

  11. New T=1 effective interactions for the f5/2 p3/2 p1/2 g9/2 model space; Implications for valence-mirror symmetry and seniority isomers

    CERN Document Server

    Lisetskiy, A F; Horoi, M; Grawe, H

    2004-01-01

    New shell model Hamiltonians are derived for the T=1 part of the residual interaction in the f5/2 p3/2 p1/2 g9/2 model space based on the analysis and fit of the available experimental data for 57Ni-78Ni isotopes and 77Cu-100Sn isotones. The fit procedure, properties of the determined effective interaction as well as new results for valence-mirror symmetry and seniority isomers for nuclei near 78Ni and 100Sn are discussed.

  12. Curcumin improves the therapeutic efficacy of Listeria(at)-Mage-b vaccine in correlation with improved T-cell responses in blood of a triple-negative breast cancer model 4T1.

    Science.gov (United States)

    Singh, Manisha; Ramos, Ilyssa; Asafu-Adjei, Denise; Quispe-Tintaya, Wilber; Chandra, Dinesh; Jahangir, Arthee; Zang, Xingxing; Aggarwal, Bharat B; Gravekamp, Claudia

    2013-08-01

    Success of cancer vaccination is strongly hampered by immune suppression in the tumor microenvironment (TME). Interleukin (IL)-6 is particularly and highly produced by triple-negative breast cancer (TNBC) cells, and has been considered as an important contributor to immune suppression in the TME. Therefore, we hypothesized that IL-6 reduction may improve efficacy of vaccination against TNBC cancer through improved T-cell responses. To prove this hypothesis, we investigated the effect of curcumin, an inhibitor of IL-6 production, on vaccination of a highly attenuated Listeria monocytogenes (Listeria(at)), encoding tumor-associated antigens (TAA) Mage-b in a TNBC model 4T1. Two therapeutic vaccination strategies with Listeria(at)-Mage-b and curcumin were tested. The first immunization strategy involved all Listeria(at)-Mage-b vaccinations and curcumin after tumor development. As curcumin has been consumed all over the world, the second immunization strategy involved curcumin before and all therapeutic vaccinations with Listeria(at)-Mage-b after tumor development. Here, we demonstrate that curcumin significantly improves therapeutic efficacy of Listeria(at)-Mage-b with both immunization strategies particularly against metastases in a TNBC model (4T1). The combination therapy was slightly but significantly more effective against the metastases when curcumin was administered before compared to after tumor development. With curcumin before tumor development in the combination therapy, the production of IL-6 was significantly decreased and IL-12 increased by myeloid-derived suppressor cells (MDSC), in correlation with improved CD4 and CD8 T-cell responses in blood. Our study suggests that curcumin improves the efficacy of Listeria(at)-Mage-b vaccine against metastases in TNBC model 4T1 through reversal of tumor-induced immune suppression.

  13. T1 difficulty modulates the attentional blink only when T1 is unmasked

    DEFF Research Database (Denmark)

    Nielsen, Simon; Andersen, Tobias S

    processing resources being occupied by T1 when T2 is presented. If so, it is expected that varying T1 difficulty should modulate the AB magnitude. Previous findings however are inconsistent: Christmann & Leuthold (2004) manipulated T1 difficulty by contrast and found that an easy T1 (high contrast) decreased...... with contrast and exposure. We suggested that the use of pattern masks might have compromised ours, and similar studies. In a new set of experiments we test this hypothesis and vary T1 difficulty with contrast, only this time we omit T1's mask. We find significant AB interference from manipulating T1....... We hypothesize that the rapid onset of T1 induces an attentional capture effect, which increases with contrast. This challenges the use of contrast to manipulate T1 in studies examining how an easy T1 affects the AB – any positive effects may be compromised by the increased capture effect....

  14. Evaluation of PepT1 transport of food-derived antihypertensive peptides, Ile-Pro-Pro and Leu-Lys-Pro using in vitro, ex vivo and in vivo transport models.

    Science.gov (United States)

    Gleeson, John P; Brayden, David J; Ryan, Sinéad M

    2017-06-01

    Ile-Pro-Pro (IPP) and Leu-Lys-Pro (LKP) are food-derived antihypertensive peptides which inhibit angiotensin-converting enzyme (ACE) and may have potential to attenuate hypertension. There is debate over their mechanism of uptake across small intestinal epithelia, but paracellular and PepT1 carrier-mediated uptake are thought to be important routes. The aim of this study was to determine their routes of intestinal permeability using in vitro, ex vivo and in vivo intestinal models. The presence of an apical side pH of 6.5 (mimicking the intestinal acidic microclimate) and of Gly-Sar (a high affinity competitive inhibitor and substrate for PepT1) were tested on the transepithelial apical to basolateral (A to B) transport of [(3)H]-IPP and [(3)H]-LKP across filter-grown Caco-2 monolayers in vitro and rat jejunal mucosae ex vivo. A buffer pH of 6.5 on the apical side enabled Gly-Sar to reduce the apparent permeability (Papp) of [(3)H]-IPP and [(3)H]-LKP, but this inhibition was not evident at an apical buffer pH of 7.4. Gly-Sar reduced the Papp across isolated jejunal mucosae and the area under the curve (AUC) in intra-jejunal instillations when the apical/luminal buffer pH was either 7.4 or 6.5. However, the jejunal surface acidic pH was maintained in rat jejunal tissue even when the apical side buffer pH was 7.4 due to the presence of the microclimate which is not present in monolayers. PepT1 expression was confirmed by immunofluorescence on monolayers and brush border of rat jejunal tissue. This data suggest that IPP and LKP are highly permeable and cross small intestinal epithelia in part by the PepT1 transporter, with an additional contribution from the paracellular route. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. 具有脉冲的时滞方程x′(t)=r(t)(1-ex(t-τ))/(1+λex(t-τ))的解的渐近分析%ASYMPTOTIC ANALYSIS OF SOLUTIONS OF DELAY POPULATION MODEL WITH x′(t)=r(t)(1-ex(t-τ))/(1+λex(t-τ)) IMPULSIVES

    Institute of Scientific and Technical Information of China (English)

    张志红

    2002-01-01

    考虑具有脉冲的时滞方程x′(t)=r(t)(1-ex(t-τ))/(1+λex(t-τ)), t≥t\\-0, t≠t\\-k, k=1,2,…,x(t\\++\\-k)-x(t\\-k)=b\\-kx(t\\-k), k=1,2,…,(*) 其中τ>0, λ>0, r(t)∈C([t0,+∞), R\\++),b\\-k>-1且{t\\-k}满足t\\-0<t\\-1

  16. The Earth's oscillating electric field (T = 1 day) in relation to the occurrence time of large EQs (Ms \\geq 5.0R). A postulated theoretical physical working model and its statistical validation

    CERN Document Server

    Thanassoulas, C; Verveniotis, G; Zymaris, N

    2011-01-01

    The mechanically oscillating, due to tidal forces, lithosperic plate activates, because of its high content in quartzite, the generation of a piezoelectric field. Due to the same mechanical oscillation the lithosphere is generally at a state of an oscillating stress load. Therefore, large EQs which occur at the peaks of the stress load must coincide with the peaks of the generated piezoelectric potential. In this work a physical mechanism is postulated that accounts for the latter hypothesis. The postulated model is statistically tested by comparing the time of occurrence of 280 large EQs (Ms \\geq 5.0R) which occurred during the period from 2003 to 2011, to the same period of time Earth's electric field registered at ATH (Athens) and PYR (Pyrgos) monitoring sites located in Greece. The comparison has been made for the oscillating component of T = 1 day and for both the E - W and N - S directions. The statistical results indicate that the postulated model does not behave randomly. Instead, it represents a smoo...

  17. Empirical Model for Predicting Contents of Monoglyceride and Diglyceride during the Synthesis of Acyglycerols by T1 Lipase-Catalyzed Esterification%T1脂肪酶催化合成甘油酯过程中MAG与DAG最大含量预测模型研究

    Institute of Scientific and Technical Information of China (English)

    覃小丽; 钟金锋; 王永华

    2014-01-01

    单甘酯(MAG)和甘油二酯(DAG)作为一类多功能添加剂,广泛应用于食品和化妆品等行业.本文利用T1脂肪酶催化甘油和油酸酯化反应合成甘油酯,探讨了底物摩尔比、水添加量、反应时间和温度对产物MAG和DAG含量的影响.结果表明,MAG含量随着反应时间的进行呈现先增大后缓慢减少的趋势,DAG含量则随着时间的进行先快速增大后趋于平衡的趋势,甘油三酯呈现不断增加的趋势.在给定温度范围内(40~60℃),温度对DAG和MAG含量影响可忽略不计.基于该过程摩尔比和水添加量的影响,建立了MAG和DAG含量变化规律的预测模型,ErDAG%=0.5967×r0.271 ×(-1.01Dw+40.2),ErMAG%=0.7422×r0.366×(-0.745 Dw+23.7),实验实测值与模型预测值之间相近程度的曲线拟合相关系数(R2)均达到0.99以上.可见,在本实验范围下,该模型可有效预测反应过程DAG和MAG最大含量的变化规律.本模型将为T1脂肪酶催化合成甘油酯过程中MAG和DAG最大含量变化的生产实践提供很好的指导.

  18. Advanced Colloids Experiment (ACE-T1)

    Science.gov (United States)

    Meyer, William V.; Sicker, Ron; Brown, Dan; Eustace, John

    2015-01-01

    Increment 45 - 46 Science Symposium presentation of Advanced Colloids Experiment (ACE-T1) to RPO. The purpose of this event is for Principal Investigators to present their science objectives, testing approach, and measurement methods to agency scientists, managers, and other investigators.

  19. Magnetic Resonance Water Proton Relaxation in Protein Solutions and Tissue: T1ρ Dispersion Characterization

    Science.gov (United States)

    Chen, Enn-Ling; Kim, Raymond J.

    2010-01-01

    Background Image contrast in clinical MRI is often determined by differences in tissue water proton relaxation behavior. However, many aspects of water proton relaxation in complex biological media, such as protein solutions and tissue are not well understood, perhaps due to the limited empirical data. Principal Findings Water proton T1, T2, and T1ρ of protein solutions and tissue were measured systematically under multiple conditions. Crosslinking or aggregation of protein decreased T2 and T1ρ, but did not change high-field T1. T1ρ dispersion profiles were similar for crosslinked protein solutions, myocardial tissue, and cartilage, and exhibited power law behavior with T1ρ(0) values that closely approximated T2. The T1ρ dispersion of mobile protein solutions was flat above 5 kHz, but showed a steep curve below 5 kHz that was sensitive to changes in pH. The T1ρ dispersion of crosslinked BSA and cartilage in DMSO solvent closely resembled that of water solvent above 5 kHz but showed decreased dispersion below 5 kHz. Conclusions Proton exchange is a minor pathway for tissue T1 and T1ρ relaxation above 5 kHz. Potential models for relaxation are discussed, however the same molecular mechanism appears to be responsible across 5 decades of frequencies from T1ρ to T1. PMID:20052404

  20. Distinct human and mouse membrane trafficking systems for sweet taste receptors T1r2 and T1r3.

    Science.gov (United States)

    Shimizu, Madoka; Goto, Masao; Kawai, Takayuki; Yamashita, Atsuko; Kusakabe, Yuko

    2014-01-01

    The sweet taste receptors T1r2 and T1r3 are included in the T1r taste receptor family that belongs to class C of the G protein-coupled receptors. Heterodimerization of T1r2 and T1r3 is required for the perception of sweet substances, but little is known about the mechanisms underlying this heterodimerization, including membrane trafficking. We developed tagged mouse T1r2 and T1r3, and human T1R2 and T1R3 and evaluated membrane trafficking in human embryonic kidney 293 (HEK293) cells. We found that human T1R3 surface expression was only observed when human T1R3 was coexpressed with human T1R2, whereas mouse T1r3 was expressed without mouse T1r2 expression. A domain-swapped chimera and truncated human T1R3 mutant showed that the Venus flytrap module and cysteine-rich domain (CRD) of human T1R3 contain a region related to the inhibition of human T1R3 membrane trafficking and coordinated regulation of human T1R3 membrane trafficking. We also found that the Venus flytrap module of both human T1R2 and T1R3 are needed for membrane trafficking, suggesting that the coexpression of human T1R2 and T1R3 is required for this event. These results suggest that the Venus flytrap module and CRD receive taste substances and play roles in membrane trafficking of human T1R2 and T1R3. These features are different from those of mouse receptors, indicating that human T1R2 and T1R3 are likely to have a novel membrane trafficking system.

  1. B超弹性成像监测下应用吉西他滨耐药乳腺癌细胞4T1构建裸鼠乳腺癌肝转移模型%Application of a gemcitabine-resistant variant of breast cancer cell line (4T1/Gem) to construct nude mouse models of breast cancer with hepatic metastasis under ultrasonic elastography

    Institute of Scientific and Technical Information of China (English)

    叶志东; 黄迪; 黄宇; 张强; 麦振豪; 赵俐; 古维立

    2016-01-01

    目的 构建吉西他滨耐药乳腺癌细胞4T1耐药株并建立裸鼠乳腺癌肝转移模型.方法 采用低浓度加量持续诱导法,诱导吉西他滨耐药乳腺癌细胞4T1耐药株,命名为4T1/Gem;CCK-8法测定4T1与4T1/Gem细胞的增殖抑制率,计算耐药指数;Western blot法检测细胞P-gp蛋白表达;B超引导下注射4T1/Gem细胞悬液诱导裸鼠肝脏成瘤;HE染色观察肿瘤组织病理情况,免疫组化法检测瘤组织ER、PR、HER2、Ki-67和P-gp蛋白的表达.结果 经过14个月的诱导成功建立4T1/Gem细胞株,可在含40μg/mL的Gem培养液中稳定生长.4T1/Gem细胞耐药指数为4T1细胞的788.547倍.与亲代相比,4T1/Gem处于G1期和G2期的细胞增加,S期细胞减少;上调P-gp蛋白的表达.4T1/Gem细胞成功建立裸鼠乳腺癌肝转移模型,瘤组织中ER、PR、HER2蛋白阴性表达,Ki-67阳性10%和P-gp蛋白阳性表达.结论 成功构建吉西他滨耐药乳腺癌细胞4T1耐药株并建立裸鼠乳腺癌肝转移模型,为开发治疗乳腺癌肝转移化疗耐药的药物提供实验基础.

  2. T1/ST2 promotes T helper 2 cell activation and polyfunctionality in bronchopulmonary mycosis.

    Science.gov (United States)

    Piehler, D; Grahnert, A; Eschke, M; Richter, T; Köhler, G; Stenzel, W; Alber, G

    2013-03-01

    Interleukin (IL)-33 enhances T helper (Th)2 immunity via its receptor T1/ST2. Infection with the yeast-like pathogen Cryptococcus neoformans is usually controlled by a Th1-mediated immune response. The mechanisms responsible for nonprotective Th2 immunity leading to allergic inflammation in pulmonary cryptococcosis are still not fully understood. Using a murine pulmonary model of C. neoformans infection, we report that T1/ST2 expression correlates with the intensity of Th2 activation, as demonstrated by the expression of CD25 and CD44 and downregulation of CD62L. Antigen-specific T1/ST2(+) Th cells are the primary source of the Th2 cytokines IL-5 and IL-13 as compared with wild-type T1/ST2(-) Th cells or Th cells from T1/ST2(-/-) mice. In addition, T1/ST2(+) Th cells almost exclusively contain bi- and trifunctional Th2 cytokine-producing Th cells compared with T1/ST2(-) Th cells or Th cells from T1/ST2(-/-) mice. Finally, T1/ST2-driven Th2 development resulted in defective pulmonary fungal control. These data demonstrate that T1/ST2 directs Th2 cell activation and polyfunctionality in allergic bronchopulmonary mycosis.

  3. Comparison of Trifecta and Pentafecta Outcomes between T1a and T1b Renal Masses following Robot-Assisted Partial Nephrectomy (RAPN with Minimum One Year Follow Up: Can RAPN for T1b Renal Masses Be Feasible?

    Directory of Open Access Journals (Sweden)

    Dae Keun Kim

    Full Text Available To investigate the feasibility of RAPN on T1b renal mass by assessment of Trifecta and Pentafecta rate between T1a and T1b renal mass.We retrospectively reviewed the medical records of 277 cases of RPN performed from 2006 to 2015. Sixty patients with clinically T1b renal masses (> 4 cm and ≤ 7 cm were identified, and from 180 patients with clinically T1a renal mass, 60 patients were matched with T1b renal mass by propensity score. Tumor complexity was investigated according to R.E.N.A.L nephrometry score. "Pentafecta" was defined as achievement of Trifecta (negative surgical margin, no postoperative complications and warm ischemia time of ≤ 25 minutes with addition of over 90% estimated GFR preservation and no chronic kidney disease stage upgrading at 1 year postoperative period. Propensity score matching was performed by OneToManyMTCH. Logistic regression models were used to identify the variables which predict the Trifecta, and Pentafecta ac.Preoperative variables (age, sex, body mass index, ASA score were similar between T1a and T1b after propensity score matching. The median R.E.N.A.L. nephrometry score was 8 vs 9 for T1a and T1b respectively (p<0.001. The median warm ischemia time was 20.1 min vs 26.2 min (p<0.001. Positive surgical margin rate was 5% vs 6.6% (p = 0.729 and overall complication rate of 13.3%. vs 15% (p = 0.793. The rate of achievement of Trifecta rate were 65.3% vs 43.3% (p = 0.017 and Pentafecta rate were 38.3% vs 26.7% (p = 0.172. For achievement of Pentafecta, R.E.N.A.L nephrometry score (HR 0.80; 95% CI (0.67-0.97; p = 0.031 was significant predictor of achieving Pentafecta. Subanalyis to assess the component of R.E.N.A.L nephrometry score, L component (location relative to the polar lines, HR 0.63; 95% CI (0.38-1.03; P = 0.064 was relatively important component for Pentafecta achievement.The rate of Pentafecta after RAPN was comparable between T1a and T1b renal masses. RAPN is a feasible modality with excellent

  4. Modelling of the transfer of Cs-137 from air to crops, milk, beef and human body following the Chernobyl accident in a location in Central Bohemia. Test of the model PRYMA T1

    Energy Technology Data Exchange (ETDEWEB)

    Carrasco, E.; Garcia-Olivares, A.; Suanez, A.; Robles, B.; Simon, I.; Cancio, D.

    1994-07-01

    This work was made in the frame of the research programme on validation od models for the transfer of radionuclides in the terrestrial, urban and aquatic environments. the acronym of this programme is VAMP (Validation of Model Predictions) and is co-ordinated by the International Atomic energy Agency (IAEA) and the Commission of the european Communities (CEC). The scenario was named CB and Was presented by the Multiple Pathway Working group. the scenario description was at the beginning a blind test, that is without knowing the location or the measured concentrations and doses. the input information included data of contamination in Cs-137 from the Chernobyl accident in Central Europe, in air and soils and ore, description of the scenario (data about crops, cattle, demography, human diet, etc.). the aim of the exercise was the contrast between model results and between observed data and model predictions. In this work the results obtained by the CIEMAT-IMA group of modelers are shown and discussed. (Author) 24 refs.

  5. An analytical model which determines the apparent T1 for Modified Look-Locker Inversion Recovery - Analysis of the longitudinal relaxation under the influence of discontinuous balanced (classical MOLLI) and spoiled gradient echo readouts.

    Science.gov (United States)

    Kampf, Thomas; Reiter, Theresa; Bauer, Wolfgang Rudolf

    2017-08-09

    Quantitative nuclear magnetic resonance imaging (MRI) shifts more and more into the focus of clinical research. Especially determination of relaxation times without/and with contrast agents becomes the foundation of tissue characterization, e.g. in cardiac MRI for myocardial fibrosis. Techniques which assess longitudinal relaxation times rely on repetitive application of readout modules, which are interrupted by free relaxation periods, e.g. the Modified Look-Locker Inversion Recovery = MOLLI sequence. These discontinuous sequences reveal an apparent relaxation time, and, by techniques extrapolated from continuous readout sequences, a putative real T1 is determined. What is missing is a rigorous analysis of the dependence of the apparent relaxation time on its real partner, readout sequence parameters and biological parameters as heart rate. This is provided in this paper for the discontinuous balanced steady state free precession (bSSFP) and spoiled gradient echo readouts. It turns out that the apparent longitudinal relaxation rate is the time average of the relaxation rates during the readout module, and free relaxation period. Knowing the heart rate our results vice versa allow to determine the real T1 from its measured apparent partner. Copyright © 2017. Published by Elsevier GmbH.

  6. A simple method for NMR t1 noise suppression

    Science.gov (United States)

    Mo, Huaping; Harwood, John S.; Yang, Danzhou; Post, Carol Beth

    2017-03-01

    t1 noise appears as random or semi-random spurious streaks along the indirect t1 (F1) dimension of a 2D or nD NMR spectrum. It can significantly downgrade spectral quality, especially for spectra with strong diagonal signals such as NOESY, because useful and weak cross-peaks can be easily buried under t1 noise. One of the significant contributing factors to t1 noise is unwanted and semi-random F2 signal modulation during t1 acquisition. As such, t1 noise from different acquisitions is unlikely to correlate with each other strongly. In the case of NOESY, co-addition of multiple spectra significantly reduces t1 noise compared with conventional acquisition with the same amount of total acquisition time and resolution.

  7. Direct reconstruction of T1 from k-space using a radial saturation-recovery sequence

    Science.gov (United States)

    Chen, Liyong; DiBella, Edward V. R.

    2011-03-01

    Contrast agent concentration ([CA]) must be known accurately to quantify dynamic contrast-enhanced (DCE) MR imaging. Accurate concentrations can be obtained if the longitudinal relaxation rate constant T1 is known both pre- and post-contrast injection. Post-contrast signal intensity in the images is often saturated and an approximation to T1 can be difficult to obtain. One method that has been proposed for accurate T1 estimation effectively acquires multiple images with different effective saturation recovery times (eSRTs) and fits the images to the equation for T1 recovery to obtain T1 values. This was done with a radial saturation-recovery sequence for 2D imaging of myocardial perfusion with DCE MRI. This multi-SRT method assumes that the signal intensity is constant for different readouts in each image. Here this assumption is not necessary as a model-based reconstruction method is proposed that directly reconstructs an image of T1 values from k-space. The magnetization for each ray at each readout pulse is modeled in the reconstruction with Bloch equations. Computer simulations based on a 72 ray cardiac DCE MRI acquisition were used to test the method. The direct model-based reconstruction gave accurate T1 values and was slightly more accurate than the multi-SRT method that used three sub-images.

  8. Sodium and T1rho MRI for molecular and diagnostic imaging of articular cartilage.

    Science.gov (United States)

    Borthakur, Arijitt; Mellon, Eric; Niyogi, Sampreet; Witschey, Walter; Kneeland, J Bruce; Reddy, Ravinder

    2006-11-01

    In this article, both sodium magnetic resonance (MR) and T1rho relaxation mapping aimed at measuring molecular changes in cartilage for the diagnostic imaging of osteoarthritis are reviewed. First, an introduction to structure of cartilage, its degeneration in osteoarthritis (OA) and an outline of diagnostic imaging methods in quantifying molecular changes and early diagnostic aspects of cartilage degeneration are described. The sodium MRI section begins with a brief overview of the theory of sodium NMR of biological tissues and is followed by a section on multiple quantum filters that can be used to quantify both bi-exponential relaxation and residual quadrupolar interaction. Specifically, (i) the rationale behind the use of sodium MRI in quantifying proteoglycan (PG) changes, (ii) validation studies using biochemical assays, (iii) studies on human OA specimens, (iv) results on animal models and (v) clinical imaging protocols are reviewed. Results demonstrating the feasibility of quantifying PG in OA patients and comparison with that in healthy subjects are also presented. The section concludes with the discussion of advantages and potential issues with sodium MRI and the impact of new technological advancements (e.g. ultra-high field scanners and parallel imaging methods). In the theory section on T1rho, a brief description of (i) principles of measuring T1rho relaxation, (ii) pulse sequences for computing T1rho relaxation maps, (iii) issues regarding radio frequency power deposition, (iv) mechanisms that contribute to T1rho in biological tissues and (v) effects of exchange and dipolar interaction on T1rho dispersion are discussed. Correlation of T1rho relaxation rate with macromolecular content and biomechanical properties in cartilage specimens subjected to trypsin and cytokine-induced glycosaminoglycan depletion and validation against biochemical assay and histopathology are presented. Experimental T1rho data from osteoarthritic specimens, animal models

  9. The Kinetics of Joined Action of Triplet-Triplet Annihilation and First-Order Decay of Molecules in T1 State in the Case of Nondominant First-Order Process: The Kinetic Model in the Case of Spatially Periodic Excitation

    Directory of Open Access Journals (Sweden)

    Paweł Borowicz

    2013-01-01

    Full Text Available In this paper the model developed for estimation of the diffusion coefficient of the molecules in the triplet state is presented. The model is based on the intuitive modification of the Smoluchowski equation for the time-dependent rate parameter. Since the sample is irradiated with the spatially periodic pattern nonexponential effects can be expected in the areas of the constructive interference of the exciting laser beams. This nonexponential effects introduce changes in the observed kinetics of the diffusion-controlled triplet-triplet annihilation. Due to irradiation with so-called long excitation pulse these non-exponential effects are very weak, so they can be described with introducing very simple correction to the kinetic model described in the first paper of this series. The values of diffusion coefficient of anthracene are used to calculate the annihilation radius from the data for spatially homogeneous excitation.

  10. Modelling of the transfer of CS-137 from air to crops, milk, beef and human body following the Chernobyl accident, in a location in Central Bohemia. Test of the model PRYMA T1; Modelizacion de la transferencia de CS-137 desde el aire a las cosechas, la leche, la carne de vacuno y el cuerpo humano producido por el accidente de Chernobyl, en una localizacion en la Bohemia Central. Test del modelo PRYMA T1

    Energy Technology Data Exchange (ETDEWEB)

    Carrasco, E.; Garcia-Olivares, A.; Suaez, A.; Robles, B. Simon, I.; Cancio, D.

    1994-07-01

    This work was made in the frame of the research programme on validation of models for the transfer of radionuclides in the terrestrial, urban and aquatic environments. The acronym of this programme is VAMP (Validation of Model Predictions) and is coordinated by the International Atomic Energy Agency (IAEA) and the Commission of the European Communities (CEC). The scenario was named CB and was presented by the Multiple Pathway Working group. The scenario description was at the beginning a blind test, that is without knowing the location or the measured concentrations and doses. The input information included data of contamination in Cs-137 from the Chernobyl accident in Central Europe, in air and soils and more description of the scenario (data about crops, cattele, demography, human diet, etc.). The aim of the exercise was the contrast between model results and between observed data and model predictions. In this work the results obtained by the CIEMAT-IMA group of modelers are shown and discussed.

  11. A medical device-grade T1 and ECV phantom for global T1 mapping quality assurance—the T1 Mapping and ECV Standardization in cardiovascular magnetic resonance (T1MES) program

    NARCIS (Netherlands)

    Captur, Gabriella; Gatehouse, Peter; Keenan, Kathryn; Heslinga, Friso Gerben; Bruehl, Ruediger; Prothmann, Marcel; Graves, Martin J.; Eames, Richard J.; Torlasco, Camilla; Benedetti, Giulia; Donovan, Jacqueline; Itterman, Bernd; Boubertakh, Redha; Bathgate, Andrew; Royet, Celine; Pang, Wenjie; Nezafat, Reza; Salerno, Michael; Kellman, Peter; Moon, James C.

    2016-01-01

    Background T1 mapping and extracellular volume (ECV) have the potential to guide patient care and serve as surrogate end-points in clinical trials, but measurements differ between cardiovascular magnetic resonance (CMR) scanners and pulse sequences. To help deliver T1 mapping to global clinical

  12. A medical device-grade T1 and ECV phantom for global T1 mapping quality assurance—the T1 Mapping and ECV Standardization in cardiovascular magnetic resonance (T1MES) program

    NARCIS (Netherlands)

    Captur, Gabriella; Gatehouse, Peter; Keenan, Kathryn; Heslinga, Friso Gerben; Bruehl, Ruediger; Prothmann, Marcel; Graves, Martin J.; Eames, Richard J.; Torlasco, Camilla; Benedetti, Giulia; Donovan, Jacqueline; Itterman, Bernd; Boubertakh, Redha; Bathgate, Andrew; Royet, Celine; Pang, Wenjie; Nezafat, Reza; Salerno, Michael; Kellman, Peter; Moon, James C.

    2016-01-01

    Background T1 mapping and extracellular volume (ECV) have the potential to guide patient care and serve as surrogate end-points in clinical trials, but measurements differ between cardiovascular magnetic resonance (CMR) scanners and pulse sequences. To help deliver T1 mapping to global clinical care

  13. Three-dimensional ultrashort echo time cones T1ρ (3D UTE-cones-T1ρ ) imaging.

    Science.gov (United States)

    Ma, Ya-Jun; Carl, Michael; Shao, Hongda; Tadros, Anthony S; Chang, Eric Y; Du, Jiang

    2017-03-20

    We report a novel three-dimensional (3D) ultrashort echo time (UTE) sequence employing Cones trajectory and T1ρ preparation (UTE-Cones-T1ρ ) for quantitative T1ρ assessment of short T2 tissues in the musculoskeletal system. A basic 3D UTE-Cones sequence was combined with a spin-locking preparation pulse for T1ρ contrast. A relatively short TR was used to decrease the scan time, which required T1 measurement and compensation using 3D UTE-Cones data acquisitions with variable TRs. Another strategy to reduce the total scan time was to acquire multiple Cones spokes (Nsp ) after each T1ρ preparation and fat saturation. Four spin-locking times (TSL = 0-20 ms) were acquired over 12 min, plus another 7 min for T1 measurement. The 3D UTE-Cones-T1ρ sequence was compared with a two-dimensional (2D) spiral-T1ρ sequence for the imaging of a spherical CuSO4 phantom and ex vivo meniscus and tendon specimens, as well as the knee and ankle joints of healthy volunteers, using a clinical 3-T scanner. The CuSO4 phantom showed a T1ρ value of 76.5 ± 1.6 ms with the 2D spiral-T1ρ sequence, as well as 85.7 ± 3.6 and 89.2 ± 1.4 ms for the 3D UTE-Cones-T1ρ sequences with Nsp of 1 and 5, respectively. The 3D UTE-Cones-T1ρ sequence provided shorter T1ρ values for the bovine meniscus sample relative to the 2D spiral-T1ρ sequence (10-12 ms versus 16 ms, respectively). The cadaveric human Achilles tendon sample could only be imaged with the 3D UTE-Cones-T1ρ sequence (T1ρ  = 4.0 ± 0.9 ms), with the 2D spiral-T1ρ sequence demonstrating near-zero signal intensity. Human studies yielded T1ρ values of 36.1 ± 2.9, 18.3 ± 3.9 and 3.1 ± 0.4 ms for articular cartilage, meniscus and the Achilles tendon, respectively. The 3D UTE-Cones-T1ρ sequence allows volumetric T1ρ measurement of short T2 tissues in vivo.

  14. Dynamic Quantitative T1 Mapping in Orthotopic Brain Tumor Xenografts

    Directory of Open Access Journals (Sweden)

    Kelsey Herrmann

    2016-04-01

    Full Text Available Human brain tumors such as glioblastomas are typically detected using conventional, nonquantitative magnetic resonance imaging (MRI techniques, such as T2-weighted and contrast enhanced T1-weighted MRI. In this manuscript, we tested whether dynamic quantitative T1 mapping by MRI can localize orthotopic glioma tumors in an objective manner. Quantitative T1 mapping was performed by MRI over multiple time points using the conventional contrast agent Optimark. We compared signal differences to determine the gadolinium concentration in tissues over time. The T1 parametric maps made it easy to identify the regions of contrast enhancement and thus tumor location. Doubling the typical human dose of contrast agent resulted in a clearer demarcation of these tumors. Therefore, T1 mapping of brain tumors is gadolinium dose dependent and improves detection of tumors by MRI. The use of T1 maps provides a quantitative means to evaluate tumor detection by gadolinium-based contrast agents over time. This dynamic quantitative T1 mapping technique will also enable future quantitative evaluation of various targeted MRI contrast agents.

  15. QIN: Practical Considerations in T1 Mapping of Prostate for Dynamic Contrast Enhancement Pharmacokinetic Analyses

    Science.gov (United States)

    Fennessy, Fiona M; Fedorov, Andriy; Gupta, Sandeep N; Schmidt, Ehud J; Tempany, Clare M; Mulkern, Robert V

    2012-01-01

    There are many challenges in developing robust imaging biomarkers that can be reliably applied in a clinical trial setting. In the case of Dynamic Contrast Enhanced (DCE) MRI, one such challenge is to obtain accurate pre-contrast T1 maps for subsequent use in two-compartment pharmacokinetic models commonly used to fit the MR enhancement time courses. In the prostate, a convenient and common approach for this task has been to use the same 3D SPGR sequence used to collect the DCE data, but with variable flip angles (VFA’s) to collect data suitable for T1 mapping prior to contrast injection. However, inhomogeneous radiofrequency conditions within the prostate have been found to adversely affect the accuracy of this technique. Herein we demonstrate the sensitivity of DCE pharmacokinetic parameters to pre-contrast T1 values and examine methods to improve the accuracy of T1 mapping with flip angle corrected VFA SPGR methods, comparing T1 maps from such methods with reference T1 maps generated with saturation recovery experiments performed with fast spin echo (FSE) sequences. PMID:22898681

  16. T1 theorem for Besov and Triebel-Lizorkin spaces

    Institute of Scientific and Technical Information of China (English)

    DENG Donggao; HAN Yongsheng

    2005-01-01

    Using the discrete Calderon type reproducing formula and the PlancherelPolya characterization for the Besov and Triebel-Lizorkin spaces, the T1 theorem for the Besov and Triebel-Lizorkin spaces was proved.

  17. Relationship Between T1 Slope and Cervical Alignment Following Multilevel Posterior Cervical Fusion Surgery: Impact of T1 Slope Minus Cervical Lordosis.

    Science.gov (United States)

    Hyun, Seung-Jae; Kim, Ki-Jeong; Jahng, Tae-Ahn; Kim, Hyun-Jib

    2016-04-01

    Retrospective study. To assess the relationship between sagittal alignment of the cervical spine and patient-reported health-related quality-of-life scores following multilevel posterior cervical fusion, and to explore whether an analogous relationship exists in the cervical spine using T1 slope minus C2-C7 lordosis (T1S-CL). A recent study demonstrated that, similar to the thoracolumbar spine, the severity of disability increases with sagittal malalignment following cervical reconstruction surgery. From 2007 to 2013, 38 consecutive patients underwent multilevel posterior cervical fusion for cervical stenosis, myelopathy, and deformities. Radiographic measurements included C0-C2 lordosis, C2-C7 lordosis, C2-C7 sagittal vertical axis (SVA), T1 slope, and T1S-CL. Pearson correlation coefficients were calculated between pairs of radiographic measures and health-related quality-of-life. C2-C7 SVA positively correlated with neck disability index (NDI) scores (r = 0.495). C2-C7 lordosis (P = 0.001) and T1S-CL (P = 0.002) changes correlated with NDI score changes after surgery. For significant correlations between C2-C7 SVA and NDI scores, regression models predicted a threshold C2-C7 SVA value of 50 mm, beyond which correlations were most significant. The T1S-CL also correlated positively with C2-C7 SVA and NDI scores (r = 0.871 and r = 0.470, respectively). Results of the regression analysis indicated that a C2-C7 SVA value of 50 mm corresponded to a T1S-CL value of 26.1°. This study showed that disability of the neck increased with cervical sagittal malalignment following surgical reconstruction and a greater T1S-CL mismatch was associated with a greater degree of cervical malalignment. Specifically, a mismatch greater than 26.1° corresponded to positive cervical sagittal malalignment, defined as C2-C7 SVA greater than 50 mm. 3.

  18. Flowing Foam: T1 events and solid-liquid transitions.

    Science.gov (United States)

    Dennin, Michael

    2005-11-01

    Flowing aqueous foam is found in many applications ranging from oil recovery, to fire fighting, to spreading shaving cream. Aqueous foam consists of gas bubbles with liquid walls. One of the striking features of foam is that despite being composed entirely of fluids, its mechanical properties are either those of a solid (elastic response) or fluid (viscous flow), depending on the nature of the applied stress and strains. We study the transition between these two regimes using a model foam system: bubble rafts. Bubble rafts are a single layer of bubbles floating on the air-water surface. This allows us to track the motion of all the bubbles during flow. In this talk, we will present two main results. First, we will discuss the observation of the coexistence between a solid-like and fluid-like state during flow. Second, we will discuss the role played by nonlinear, topological rearrangements, known as T1 events, in determining the mechanical response of the system.

  19. Hyperpolarized (129)Xe T (1) in oxygenated and deoxygenated blood

    Science.gov (United States)

    Albert, M. S.; Balamore, D.; Kacher, D. F.; Venkatesh, A. K.; Jolesz, F. A.

    2000-01-01

    The viability of the new technique of hyperpolarized (129)Xe MRI (HypX-MRI) for imaging organs other than the lungs depends on whether the spin-lattice relaxation time, T(1), of (129)Xe is sufficiently long in the blood. In previous experiments by the authors, the T(1) was found to be strongly dependent upon the oxygenation of the blood, with T(1) increasing from about 3 s in deoxygenated samples to about 10 s in oxygenated samples. Contrarily, Tseng et al. (J. Magn. Reson. 1997; 126: 79-86) reported extremely long T(1) values deduced from an indirect experiment in which hyperpolarized (129)Xe was used to create a 'blood-foam'. They found that oxygenation decreased T(1). Pivotal to their experiment is the continual and rapid exchange of hyperpolarized (129)Xe between the gas phase (within blood-foam bubbles) and the dissolved phase (in the skin of the bubbles); this necessitated a complicated analysis to extract the T(1) of (129)Xe in blood. In the present study, the experimental design minimizes gas exchange after the initial bolus of hyperpolarized (129)Xe has been bubbled through the sample. This study confirms that oxygenation increases the T(1) of (129)Xe in blood, from about 4 s in freshly drawn venous blood, to about 13 s in blood oxygenated to arterial levels, and also shifts the red blood cell resonance to higher frequency. Copyright 2000 John Wiley & Sons, Ltd. Abbreviations used BOLD blood oxygen level dependent NOE nuclear overhouses effect PO(2) oxygen partial pressure RBC red blood cells RF radio frequency SNR signal-to-noise ratio.

  20. Systematic T1 improvement for hyperpolarized 129xenon.

    Science.gov (United States)

    Repetto, Maricel; Babcock, Earl; Blümler, Peter; Heil, Werner; Karpuk, Sergei; Tullney, Kathlynne

    2015-03-01

    The spin-lattice relaxation time T1 of hyperpolarized (HP)-(129)Xe was improved at typical storage conditions (i.e. low and homogeneous magnetic fields). Very long wall relaxation times T(1)(wall) of about 18 h were observed in uncoated, spherical GE180 glass cells of ∅=10 cm which were free of rubidium and not permanently sealed but attached to a standard glass stopcock. An "aging" process of the wall relaxation was identified by repeating measurements on the same cell. This effect could be easily removed by repeating the initial cleaning procedure. In this way, a constant wall relaxation was ensured. The Xe nuclear spin-relaxation rate 1/T1(Xe-Xe) due to van der Waals molecules was investigated too, by admixing three different buffer gases (N(2), SF(6) and CO(2)). Especially CO(2) exhibited an unexpected high efficiency (r) in shortening the lifetime of the Xe-Xe dimers and hence prolonging the total T1 relaxation even further. These measurements also yielded an improved accuracy for the van der Waals relaxation for pure Xe (with 85% (129)Xe) of T(1)(Xe-Xe)=(4.6±0.1)h. Repeating the measurements with HP (129)Xe in natural abundance in mixtures with SF6, a strong dependence of T(1)(Xe-Xe) and r on the isotopic enrichment was observed, uncovering a shorter T(1)(Xe-Xe) relaxation for the (129)Xe in natural composition as compared to the 85% isotopically enriched gas.

  1. Molecular Imaging of Tumors Using a Quantitative T1 Mapping Technique via Magnetic Resonance Imaging

    Directory of Open Access Journals (Sweden)

    Kelsey Herrmann

    2015-07-01

    Full Text Available Magnetic resonance imaging (MRI of glioblastoma multiforme (GBM with molecular imaging agents would allow for the specific localization of brain tumors. Prior studies using T1-weighted MR imaging demonstrated that the SBK2-Tris-(Gd-DOTA3 molecular imaging agent labeled heterotopic xenograft models of brain tumors more intensely than non-specific contrast agents using conventional T1-weighted imaging techniques. In this study, we used a dynamic quantitative T1 mapping strategy to more objectively compare intra-tumoral retention of the SBK2-Tris-(Gd-DOTA3 agent over time in comparison to non-targeted control agents. Our results demonstrate that the targeted SBK2-Tris-(Gd-DOTA3 agent, a scrambled-Tris-(Gd-DOTA3 control agent, and the non-specific clinical contrast agent Optimark™ all enhanced flank tumors of human glioma cells with similar maximal changes on T1 mapping. However, the retention of the agents differs. The non-specific agents show significant recovery within 20 min by an increase in T1 while the specific agent SBK2-Tris-(Gd-DOTA3 is retained in the tumors and shows little recovery over 60 min. The retention effect is demonstrated by percent change in T1 values and slope calculations as well as by calculations of gadolinium concentration in tumor compared to muscle. Quantitative T1 mapping demonstrates the superior binding and retention in tumors of the SBK2-Tris-(Gd-DOTA3 agent over time compared to the non-specific contrast agent currently in clinical use.

  2. A novel enterocin T1 with anti-Pseudomonas activity produced by Enterococcus faecium T1 from Chinese Tibet cheese.

    Science.gov (United States)

    Liu, Hui; Zhang, Lanwei; Yi, Huaxi; Han, Xue; Gao, Wei; Chi, Chunliang; Song, Wei; Li, Haiying; Liu, Chunguang

    2016-02-01

    An enterocin-producing Enterococcus faecium T1 was isolated from Chinese Tibet cheese. The enterocin was purified by SP-Sepharose and reversed phase HPLC. It was identified as unique from other reported bacteriocins based on molecular weight (4629 Da) and amino acid compositions; therefore it was subsequently named enterocin T1. Enterocin T1 was stable at 80-100 °C and over a wide pH range, pH 3.0-10.0. Protease sensitivity was observed to trypsin, pepsin, papain, proteinase K, and pronase E. Importantly, enterocin T1 was observed to inhibit the growth of numerous Gram-negative and Gram-positive bacteria including Pseudomonas putida, Pseudomonas aeruginosa, Pseudomonas fluorescens, Escherichia coli, Salmonella typhimurium, Shigella flexneri, Shigella sonnei, Staphylococcus aureus, Listeria monocytogenes. Take together, these results suggest that enterocin T1 is a novel bacteriocin with the potential to be used as a bio-preservative to control Pseudomonas spp. in food.

  3. Free-breathing MOLLI: application to myocardial T(1) mapping.

    Science.gov (United States)

    Tsai, Jyun-Ming; Huang, Teng-Yi; Tseng, Yu-Shen; Lin, Yi-Ru

    2012-12-01

    Of the myocardial T(1) mapping techniques, the modified Look-Locker inversion recovery (MOLLI) sequence is accurate and highly reproducible. The MOLLI sequence requires patients to hold their breath for 17 heartbeats during the scanning process to minimize respiratory motion-related artifacts. However, some patients are unable to hold their breath because of illness or limited breath-hold capacity. This study, therefore, aimed to develop a robust myocardial T(1) mapping method based on the MOLLI sequence for patients unable to perform voluntary breath-holds. This study presents a free-breathing MOLLI (FB-MOLLI) sequence and an optimized reconstruction method to allow myocardial T(1) mapping in vivo without breath-hold. Nine healthy volunteers participated in this study after providing institutionally approved consent. The FB-MOLLI sequence acquires 20 images within 29 heartbeats. The reconstruction program employs a two-step automatic image registration technique and an image selection method inspired by the self-gating cardiac imaging method. Results indicate that the proposed reconstruction method increases the accuracy and reproducibility of free-breathing T(1) measurements significantly (p mapping, and could greatly facilitate acquisition procedures during routine examinations.

  4. Effects of effective fraction of Epimedium,Astragalus,Radix Puerariae on the expression of DMT1 in the cerebral cortex of transgenic mice model of Alzheimer′s disease%淫羊藿、黄芪、葛根有效组分复方对阿尔茨海默病转基因模型小鼠大脑皮质DM T1表达的影响

    Institute of Scientific and Technical Information of China (English)

    董贤慧; 高维娟; 贺小平; 崔志超; 柴锡庆; 赵家晴

    2016-01-01

    目的:探讨淫羊藿、黄芪、葛根有效组分复方对阿尔茨海默症(AD)APPswe/PS1ΔE9双转基因小鼠模型大脑皮质二价金属离子转运蛋白1(DM T1)表达的影响。方法将APPswe/PS1ΔE9双转基因小鼠60只,分为模型组、淫羊藿组、黄芪组、葛根组、复方组、去铁胺(DFO )组,C57BL/6J小鼠作为健康对照组。用药结束后,取各组小鼠脑组织,分别采用免疫组织化学、实时荧光定量PCR(RT‐PCR)和蛋白免疫印迹法(Western blot)检测各组小鼠大脑皮质DMT1的表达情况。结果免疫组织化学结果显示:阴性对照未见DM T1阳性细胞。与健康对照组相比,模型组DM T1的表达增高;与模型组相比,复方组和DFO组DM T1的表达降低(P<0.05);DFO组与复方组DM T1的表达无明显差异。RT‐PCR结果、Western blot结果与免疫组织化学结果相一致。结论淫羊藿、黄芪、葛根有效组分复方可以下调AD模型小鼠大脑皮质DM T1的表达,从而抑制小鼠脑铁超载,缓解铁超载带来的中枢神经系统功能衰退。%Objective To investigate the effects of Epimedium ,Astragalus ,Radix Puerariae on DMT1 expression in the cere‐bral cortex of APPswe/PS1ΔE9 double transgenic mice model of AD .Methods A total of 60 specific‐pathogen‐free male APPswe/PS1ΔE9 double transgenic mice aged 6 months were equally and randomly assigned to model ,Epimedium ,Astragalus ,Radix puerari‐ae ,compound and DFO groups .An additional 10 6‐month‐old C57BL/6J mice served as negative control group .Using immunohisto‐chemistry and molecular biology methods to investigate the effects of a compound combining the effective components of Epimedi‐um ,Astragalus ,Radix puerariae on DMT1 expression in the cerebral cortex of APPswe/PS1ΔE9 double transgenic mice model of AD . Results Immunohistochemical staining results revealed that DM T 1 positive cell did not show in negative control

  5. [Management of T1a vocal fold carcinoma].

    Science.gov (United States)

    Reiter, R; Brosch, S; Smith, E; Pickhard, A

    2013-12-01

    About 2/3 of the larynx carcinomas affect the vocal chords. The main risk factor is smoking. Carcinomas in this localisation often arise from leukoplakias with dysplasia. A typical symptom is dysphonia. Arrest of vibration in microlaryngostroboscopy is a hint that a carcinoma could be present. Transoral laser cordectomy or radiotherapy show equivalent oncological results and results in quality of voice in the treatment of vocal fold carcinoma (T1a). As lymph node and distant metastasis are very rare, follow-up can concentrate on microlaryngoscopy. In case of a suspicious area on the vocal fold, biopsy of the affected tissue is needed to plan correct treatment. The prognosis of the T1 vocal chord carcinoma is quite good with a 5-year survival rate of almost 100%.

  6. Towards T1-limited magnetic resonance imaging using Rabi beats

    CERN Document Server

    Fedder, H; Rempp, F; Wolf, T; Hemmer, P; Jelezko, F; Wrachtrup, J

    2010-01-01

    Two proof-of-principle experiments towards T1-limited magnetic resonance imaging with NV centers in diamond are demonstrated. First, a large number of Rabi oscillations is measured and it is demonstrated that the hyperfine interaction due to the NV's 14N can be extracted from the beating oscillations. Second, the Rabi beats under V-type microwave excitation of the three hyperfine manifolds is studied experimentally and described theoretically.

  7. Towards T 1-limited magnetic resonance imaging using Rabi beats

    Science.gov (United States)

    Fedder, H.; Dolde, F.; Rempp, F.; Wolf, T.; Hemmer, P.; Jelezko, F.; Wrachtrup, J.

    2011-03-01

    Two proof-of-principle experiments toward T 1-limited magnetic resonance imaging with NV centers in diamond are demonstrated. First, a large number of Rabi oscillations is measured and it is demonstrated that the hyperfine interaction due to the NV's 14N can be extracted from the beating oscillations. Second, the Rabi beats under V-type microwave excitation of the three hyperfine manifolds is studied experimentally and described theoretically.

  8. 电动T1 大众Bulli

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    新Bulli由电动机提供动力,可容纳六名乘员,并配有iPad控制的多媒体信息娱乐系统。新车比T1车身更长、更高,但宽度比较窄,以2.62m的轴距充分利用了车身整体长度。

  9. Is mortalin a candidate gene for T1DM ?

    Science.gov (United States)

    Johannesen, Jesper; Pie, Angeles; Karlsen, Allan Ertmann; Larsen, Zenia Marian; Jensen, Allan; Vissing, Henrik; Kristiansen, Ole Peter; Pociot, Flemming; Nerup, Jørn

    2004-01-01

    Mortalin has been found to be up-regulated by 2D-protein gel analysis in isolated rodent islets exposed to cytokines. In islets from two rat strains with different sensitivity to the toxic effects of cytokines we observed a significant difference in IL-1beta mediated mortalin expression. Constitutive over-expression of rat mortalin in NIH3T3 cells reduced cellular survival in accordance with mortalin being associated to cellular senescence. Hence we consider the gene encoding for mortalin at chromosome 5q31.1 a putative candidate gene in cytokine induced beta-cell destruction. We scanned the human mortalin gene for polymorphisms and identified three novel polymorphisms. Neither the SNPs individually nor as constructed haplotypes showed disease association tested by (E)TDT in a Danish type 1 diabetes (T1DM) population. Furthermore, we tested the D5S500 microsatelite located close to 5q31.1 without finding linkage to (T1DM). In conclusion, the functional data identifying a difference in mortalin expression in IL-1beta stimulated islets between two rat strains and over-expression of mortalin in NIH3T3 cells associated with decreased viability suggests a functional role for mortalin in cytokine mediated beta cell destruction; however, the identified polymorphisms did not reveal any association in the presence of linkage disequilibrium of mortalin to T1DM in the Danish population.

  10. T1 and susceptibility contrast at high fields

    Science.gov (United States)

    Neelavalli, Jaladhar

    Clinical imaging at high magnetic field strengths (≥ 3Tesla) is sought after primarily due to the increased signal strength available at these fields. This increased SNR can be used to perform: (a) high resolution imaging in the same time as at lower field strengths; (b) the same resolution imaging with much faster acquisition; and (c) functional MR imaging (fMRI), dynamic perfusion and diffusion imaging with increased sensitivity. However they are also associated with increased power deposition (SAR) due to increase in imaging frequency and longer T1 relaxation times. Longer T1s mean longer imaging times for generating good T1 contrast images. On the other hand for faster imaging, at high fields fast spin echo or magnetization prepared sequences are conventionally proposed which are, however, associated with high SAR values. Imaging with low SAR is more and more important as we move towards high fields and particularly for patients with metallic implants like pacemakers or deep brain stimulator. The SAR limit acceptable for these patients is much less than the limit acceptable for normal subjects. A new method is proposed for imaging at high fields with good contrast with simultaneous reduction in power deposition. Further, T1 based contrast optimization problem in FLASH imaging is considered for tissues with different T1s but same spin densities. The solution providing optimal imaging parameters is simplified for quick and easy computation in a clinical setting. The efficacy of the simplification is evaluated and practical limits under which the simplification can be applied are worked out. The phase difference due to variation in magnetic susceptibility property among biological tissues is another unique source of contrast which is different from the conventional T1, T2 and T2* contrast. This susceptibility based phase contrast has become more and more important at high fields, partly due to contrast generation issues due to longer T 1s and shorter T2s and

  11. Rapid Biodegradation of the Herbicide 2,4-Dichlorophenoxyacetic Acid by Cupriavidus gilardii T-1.

    Science.gov (United States)

    Wu, Xiangwei; Wang, Wenbo; Liu, Junwei; Pan, Dandan; Tu, Xiaohui; Lv, Pei; Wang, Yi; Cao, Haiqun; Wang, Yawen; Hua, Rimao

    2017-05-10

    Phytotoxicity and environmental pollution of residual herbicides have caused much public concern during the past several decades. An indigenous bacterial strain capable of degrading 2,4-dichlorophenoxyacetic acid (2,4-D), designated T-1, was isolated from soybean field soil and identified as Cupriavidus gilardii. Strain T-1 degraded 2,4-D 3.39 times more rapidly than the model strain Cupriavidus necator JMP134. T-1 could also efficiently degrade 2-methyl-4-chlorophenoxyacetic acid (MCPA), MCPA isooctyl ester, and 2-(2,4-dichlorophenoxy)propionic acid (2,4-DP). Suitable conditions for 2,4-D degradation were pH 7.0-9.0, 37-42 °C, and 4.0 mL of inoculums. Degradation of 2,4-D was concentration-dependent. 2,4-D was degraded to 2,4-dichlorophenol (2,4-DCP) by cleavage of the ether bond and then to 3,5-dichlorocatechol (3,5-DCC) via hydroxylation, followed by ortho-cleavage to cis-2-dichlorodiene lactone (CDL). The metabolites 2,4-DCP or 3,5-DCC at 10 mg L(-1) were completely degraded within 16 h. Fast degradation of 2,4-D and its analogues highlights the potential for use of C. gilardii T-1 in bioremediation of phenoxyalkanoic acid herbicides.

  12. Difference between Extra- and IntracellularT1Values of Carboxylic Acids Affects the Quantitative Analysis of Cellular Kinetics by Hyperpolarized NMR

    DEFF Research Database (Denmark)

    Karlsson, Magnus; Jensen, Pernille Rose; Ardenkjær-Larsen, Jan Henrik;

    2016-01-01

    Incomplete knowledge of the longitudinal relaxationtime constant (T1) leads to incorrect assumptions in quantita-tive kinetic models of cellular systems, studied by hyper-polarized real-time NMR. Using an assay that measures theintracellular signal of small carboxylic acids in living cells......, theintracellular T1of the carboxylic acid moiety of acetate, keto-isocaproate, pyruvate, and butyrate was determined. Theintracellular T1is shown to be up to four-fold shorter thanthe extracellular T1. Such a large difference in T1valuesbetween the inside and the outside of the cell has significantinfluence...... on the quantification of intracellular metabolicactivity. It is expected that the significantly shorter T1valueof the carboxylic moieties inside cells is a result of macro-molecular crowding. An artificial cytosol has been preparedand applied to predict the T1of other carboxylic acids. Wedemonstrate the value...

  13. Difference between Extra- and Intracellular T1 Values of Carboxylic Acids Affects the Quantitative Analysis of Cellular Kinetics by Hyperpolarized NMR

    DEFF Research Database (Denmark)

    Karlsson, Magnus; Jensen, Pernille Rose; Ardenkjær-Larsen, Jan Henrik;

    2016-01-01

    Incomplete knowledge of the longitudinal relaxation time constant (T1) leads to incorrect assumptions in quantitative kinetic models of cellular systems, studied by hyperpolarized real-time NMR. Using an assay that measures the intracellular signal of small carboxylic acids in living cells......, the intracellular T1 of the carboxylic acid moiety of acetate, ketoisocaproate, pyruvate, and butyrate was determined. The intracellular T1 is shown to be up to four-fold shorter than the extracellular T1. Such a large difference in T1 values between the inside and the outside of the cell has significant influence...... on the quantification of intracellular metabolic activity. It is expected that the significantly shorter T1 value of the carboxylic moieties inside cells is a result of macromolecular crowding. An artificial cytosol has been prepared and applied to predict the T1 of other carboxylic acids. We demonstrate the value...

  14. Difference between Extra- and Intracellular T1 Values of Carboxylic Acids Affects the Quantitative Analysis of Cellular Kinetics by Hyperpolarized NMR.

    Science.gov (United States)

    Karlsson, Magnus; Jensen, Pernille Rose; Ardenkjaer-Larsen, Jan Henrik; Lerche, Mathilde H

    2016-10-17

    Incomplete knowledge of the longitudinal relaxation time constant (T1 ) leads to incorrect assumptions in quantitative kinetic models of cellular systems, studied by hyperpolarized real-time NMR. Using an assay that measures the intracellular signal of small carboxylic acids in living cells, the intracellular T1 of the carboxylic acid moiety of acetate, keto-isocaproate, pyruvate, and butyrate was determined. The intracellular T1 is shown to be up to four-fold shorter than the extracellular T1 . Such a large difference in T1 values between the inside and the outside of the cell has significant influence on the quantification of intracellular metabolic activity. It is expected that the significantly shorter T1 value of the carboxylic moieties inside cells is a result of macromolecular crowding. An artificial cytosol has been prepared and applied to predict the T1 of other carboxylic acids. We demonstrate the value of this prediction tool.

  15. T1w dark blood imaging improves detection of contrast enhancing lesions in multiple sclerosis.

    Science.gov (United States)

    Thaler, Christian; Schneider, Tanja; Sedlacik, Jan; Kutzner, Daniel; Stellmann, Jan-Patrick; Heesen, Christoph; Fiehler, Jens; Siemonsen, Susanne

    2017-01-01

    In multiple sclerosis (MS) the sensitivity for detection of contrast enhancing lesions (CEL) in T1-weighted scans is essential for diagnostics and therapy decisions. The purpose of our study was to evaluate the sensitivity of T1w MPRAGE scans in comparison to T1w dark blood technique (T1-DB) for CEL in MS. 3T MR imaging was performed in 37 MS patients, including T2-weighted imaging, T1w MPRAGE before and after gadolinium injection (unenhanced-T1 and T1-CE) and T1-DB imaging. After gadolinium application, the T1-DB scan was performed prior to T1-CE. From unenhanced-T1 and T1-CE scans, subtraction images (T1-SUB) were calculated. The number of CEL was determined separately on T1-CE and T1-DB by two raters independently. Lesions only detected on T1-DB scans then were verified on T1-SUB. Only lesions detected by both raters were included in further analysis. In 16 patients, at least one CEL was detected by both rater, either on T1-CE or T1-DB. All lesions that were detected on T1-CE were also detected on T1-DB images. The total number of contrast enhancing lesions detected on T1-DB images (n = 54) by both raters was significantly higher than the corresponding number of lesions identified on T1-CE (n = 27) (p = 0.01); all of these lesions could be verified on SUB images. In 21 patients, no CEL was detected in any of the sequences. The application of T1-DB technique increases the sensitivity for CEL in MS, especially for those lesions that show only subtle increase in intensity after Gadolinium application but remain hypo- or iso-intense to surrounding tissue.

  16. The electronics system of the TOTEM T1 telescope

    Energy Technology Data Exchange (ETDEWEB)

    Minutoli, S., E-mail: minutoli@ge.infn.it [Istituto Nazionale di Fisica Nucleare, Genova (Italy); Bozzo, M. [Istituto Nazionale di Fisica Nucleare, Genova (Italy); Dipartimento di Fisica, Genova (Italy); Ferro, F. [Istituto Nazionale di Fisica Nucleare, Genova (Italy); Lo Vetere, M. [Istituto Nazionale di Fisica Nucleare, Genova (Italy); Dipartimento di Fisica, Genova (Italy); Robutti, E. [Istituto Nazionale di Fisica Nucleare, Genova (Italy)

    2013-08-01

    The T1 detector of the TOTEM experiment is devoted to the measurement of the inelastic rate of proton–proton interactions at the LHC. It is made of Cathode Strip Chambers. The complete electronic chains of front-end, readout and trigger are presented here. The electronics system has been developed keeping into account the hostile environment from the point of view of both radiation and magnetic field. Dedicated VLSI circuits have been extensively used in order to optimize space and power consumption.

  17. The TOTEM T1 read out card motherboard

    CERN Document Server

    Minutoli, S; Robutti, E

    2010-01-01

    This article describes the Read Out Card (ROC) motherboard, which is the main component of the T1 forward telescope front-end electronic system. The ROC main objectives are to acquire tracking data and trigger information from the detector. It performs data conversion from electrical to optical format and transfers the data streams to the next level of the system and it implements Slow Control modules which are able to receive, decode and distribute the LHC machine low jitter clock and fast command. The ROC also provides a spy mezzanine connection based on programmable FPGA and USB2.0 for laboratory and portable DAQ debugging system

  18. The TOTEM T1 read out card motherboard

    Science.gov (United States)

    Minutoli, S.; Lo Vetere, M.; Robutti, E.

    2010-12-01

    This article describes the Read Out Card (ROC) motherboard, which is the main component of the T1 forward telescope front-end electronic system. The ROC main objectives are to acquire tracking data and trigger information from the detector. It performs data conversion from electrical to optical format and transfers the data streams to the next level of the system and it implements Slow Control modules which are able to receive, decode and distribute the LHC machine low jitter clock and fast command. The ROC also provides a spy mezzanine connection based on programmable FPGA and USB2.0 for laboratory and portable DAQ debugging system.

  19. The use of the T1 sagittal angle in predicting overall sagittal balance of the spine.

    Science.gov (United States)

    Knott, Patrick T; Mardjetko, Steven M; Techy, Fernando

    2010-11-01

    have on SVA(dens). SPSS (SPSS, Inc., Chicago, IL, USA) was used to create a regression equation using the independent variables of T1 sagittal angle, cervical lordosis, thoracic kyphosis, lumbar lordosis, sacral slope, pelvic incidence, and femoral-sacral angle and the dependent variable of SVA(dens). The model had a strong correlation (r=0.80, r(2)=0.64) and was statistically significant (pbalance had mostly low T1 tilt values, usually lower than 13°. The other variables were not shown to have a statically significant influence on SVA. This analysis shows that many factors influence the overall sagittal balance of the patient, but it may be the position of the pelvis and lower spine that have a stronger influence than the position of the upper back and neck. Unfortunately, to our knowledge, there are no studies to date that have established a normal sagittal T1 tilt angle. However, our analysis has shown that when the T1 tilt was higher than 25°, all patients had at least 10 cm of positive sagittal imbalance. It also showed that patients with negative sagittal balance had mostly low T1 tilt values, usually below 13° of angulation. The T1 sagittal angle is a measurement that may be very useful in evaluating sagittal balance, as it was the measure that most strongly correlated with SVA(dens). It has its great utility where long films cannot be obtained. Patients whose T1 tilt falls outside the range 13° to 25° should be sent for full-column radiographs for a complete evaluation of their sagittal balance. On the other hand, a T1 tilt within the above range does not guarantee a normal sagittal balance, and further investigation should be performed at the surgeon's discretion. Copyright © 2010 Elsevier Inc. All rights reserved.

  20. New T1-based superconductor T1PbSrRCuO without Ca with Tc above 100 K

    Science.gov (United States)

    Sheng, Z. Z.; Xin, Y.; Meason, J. M.

    1991-04-01

    Ca-free T1PbSrRCuO samples (R=rare earths) with Tc up to above 100 K were prepared, and studied by resistance and ac susceptibility measurements and by powder x-ray diffraction analyses. A 1212-type phase (Tl1-xPbx)Sr2(Sr1-yRy)Cu2Oz is responsible for the observed supercondcutivity. A rare-earth is required for the formation of the 1212 phase. Pb-dopping is necessary to increase the Tc of the 1212 phase from 90 K to above 100 K.

  1. The impact of reliable pre-bolus T1 measurements or a fixed T1 value in the assessment of glioma patients with Dynamic Contrast Enhancing MRI

    DEFF Research Database (Denmark)

    Tietze, Anna; Mouridsen, Kim; Mikkelsen, Irene Klærke

    2015-01-01

    Purpose: Accurate quantification of hemodynamic parameters using Dynamic Contrast Enhanced MRI (DCE) requires a measurement of tissue T1 prior to contrast injection (T1). We evaluate (i) T1 estimation using the variable flip angle (VFA) and the saturation recovery (SR) techniques and (ii) investi...

  2. Contrast-enhanced 3T MR Perfusion of Musculoskeletal Tumours: T1 Value Heterogeneity Assessment and Evaluation of the Influence of T1 Estimation Methods on Quantitative Parameters.

    Science.gov (United States)

    Gondim Teixeira, Pedro Augusto; Leplat, Christophe; Chen, Bailiang; De Verbizier, Jacques; Beaumont, Marine; Badr, Sammy; Cotten, Anne; Blum, Alain

    2017-06-14

    To evaluate intra-tumour and striated muscle T1 value heterogeneity and the influence of different methods of T1 estimation on the variability of quantitative perfusion parameters. Eighty-two patients with a histologically confirmed musculoskeletal tumour were prospectively included in this study and, with ethics committee approval, underwent contrast-enhanced MR perfusion and T1 mapping. T1 value variations in viable tumour areas and in normal-appearing striated muscle were assessed. In 20 cases, normal muscle perfusion parameters were calculated using three different methods: signal based and gadolinium concentration based on fixed and variable T1 values. Tumour and normal muscle T1 values were significantly different (p = 0.0008). T1 value heterogeneity was higher in tumours than in normal muscle (variation of 19.8% versus 13%). The T1 estimation method had a considerable influence on the variability of perfusion parameters. Fixed T1 values yielded higher coefficients of variation than variable T1 values (mean 109.6 ± 41.8% and 58.3 ± 14.1% respectively). Area under the curve was the least variable parameter (36%). T1 values in musculoskeletal tumours are significantly different and more heterogeneous than normal muscle. Patient-specific T1 estimation is needed for direct inter-patient comparison of perfusion parameters. • T1 value variation in musculoskeletal tumours is considerable. • T1 values in muscle and tumours are significantly different. • Patient-specific T1 estimation is needed for comparison of inter-patient perfusion parameters. • Technical variation is higher in permeability than semiquantitative perfusion parameters.

  3. Identification of a T1D Susceptibility Gene

    Directory of Open Access Journals (Sweden)

    Grant Morahan

    2001-01-01

    Full Text Available It is not known what causes type 1 diabetes (T1D, which affects over 1 million people in the U.S. alone. Each year, 30,000 young people in the U.S. develop this disease and depend on insulin injections thereafter. Because of the huge cost to the individual, the family, and to society in increased health care costs, it is important to find what makes these people susceptible. The disease process itself is clear: the individual’s immune system — T lymphocytes in particular — attack and destroy the body’s insulin-producing cells. But how and why this autoimmune process starts or proceeds unregulated is still not known.

  4. History of Cesarean Section Associated with Childhood Onset of T1DM in Newfoundland and Labrador, Canada

    Directory of Open Access Journals (Sweden)

    J. Phillips

    2012-01-01

    Full Text Available Objectives. Newfoundland and Labrador (NL has one of the highest incidences of Type 1 diabetes mellitus (T1DM worldwide. Rates of T1DM are increasing and the search for environmental factors that may be contributing to this increase is continuing. Methods. This was a population-based case control design involving the linkage of data from a diabetes database with live birth registration data. 266 children aged 0–15 years with T1DM were compared to age- and gender-matched controls. Chi-square analysis and multivariate conditional logistic regression were carried out to assess maternal and infant factors (including maternal age, marital status, education, T1DM, hypertension, birth order, delivery method, gestational age, size-for-gestational-age, and birth weight. Results. Cases of T1DM were more likely to be large-for-gestational-age (P=0.024 and delivered by C-section (P=0.009 as compared to controls. C-section delivery was associated with increased risk of T1DM (HR 1.41, P=0.015 when birth weight and gestational age were included in the model, but not when size-for-gestational-age was included (HR 1.3, P=0.076. Conclusions. Birth by C-section was found to be a risk factor for the development of T1DM in a region with high rates of T1DM and birth by C-section. These findings may have an impact on health practice, health care planning, and future research.

  5. Response of sensitive human ataxia and resistant T-1 cell lines to accelerated heavy ions

    Energy Technology Data Exchange (ETDEWEB)

    Tobias, C.A.; Blakely, E.A.; Chang, P.Y.; Lommel, L.; Roots, R.

    1983-07-01

    The radiation dose responses of fibroblast from a patient with Ataxia telangiectasis (AT-2SF) and an established line of human T-1 cells were studied. Nearly monoenergetic accelerated neon and argon ions were used at the Berkeley Bevalac with various residual range values. The LET of the particles varied from 30 keV/..mu..m to over 1000 keV/..mu..m. All Ataxia survival curves were exponential functions of the dose. Their radiosensitivity reached peak values at 100 to 200 keV/..mu..m. Human T-1 cells have effective sublethal damage repair as has been evidenced by split dose experiments, and they are much more resistant to low LET than to high LET radiation. The repair-misrepair model has been used to interpret these results. We have obtained mathematical expressions that describe the cross sections and inactivation coefficients for both human cell lines as a function of the LET and the type of particle used. The results suggest either that high-LET particles induce a greater number of radiolesions per track or that heavy-ions at high LET induce lesions that kill cells more effectively and that are different from those produced at low LET. We assume that the lesions induced in T-1 and Ataxia cells are qualitatively similar and that each cell line attempts to repair these lesions. The result in most irradiated Ataxia cells, however, is either lethal misrepair or incomplete repair leading to cell death. 63 references, 10 figures, 1 table.

  6. Transport Mechanism of Oligopeptide Transporter PepT1 and Drug Absorption Mediated by PepT1%寡肽转运载体PepT1的转运机制及其介导的药物吸收

    Institute of Scientific and Technical Information of China (English)

    刘畅; 魏刚; 陆伟跃

    2013-01-01

    寡肽转运载体PepT1广泛分布于人和动物体内的多种器官和组织,其底物主要为蛋白水解后的二肽和三肽.本文综合文献,阐述PepT1的体内分布及其质子依赖型的转运机制,从空间结构的角度分析其对底物分子的选择性,介绍评价底物与PepT1二者间亲和活性的体内外模型及PepT1底物修饰策略在促进药物吸收方面的应用.%Oligopeptide transporter PepT1 is widely distributed in various organs and tissues of human and animals,which substrates are mainly proteolytic dipeptides and tripeptides.Based on a literature review,the in vivo distribution of PepT1 and its proton-dependent transport mechanism are introduced and the structure of the transporter and its selectivity on the substrate molecules are elucidated in this paper.In addition,several in vitro and in vivo models for evaluation of PepTl-mediated transportation as well as the applications of suvstrate modification strategies to drug absorption are also described.

  7. T1 Colorectal Cancer with Synchronous Liver Metastasis

    Directory of Open Access Journals (Sweden)

    Kiichi Sugimoto

    2013-06-01

    Full Text Available The patient was a 68-year-old man who was admitted to our hospital with a liver tumor. Abdominal ultrasonography and computed tomography revealed a liver tumor 30 mm in diameter. On colonoscopy, a pedunculated tumor with a central depression (20 mm in diameter was observed in the ascending colon, and this tumor was considered to be invading deeply into the submucosal layer. Right hemicolectomy with D3 lymphadenectomy and partial hepatectomy were performed simultaneously. On histopathological examination of the resected specimen, the tumor was a well-differentiated tubular adenocarcinoma with 3,000 μm invasion of the submucosal layer. The liver tumor showed histological findings similar to those of the primary colorectal carcinoma. The pathological stage according to the 7th edition of the TNM classification was stage IV (T1N0M1. Nine months after the operation, computed tomography revealed hepatic hilar lymph node metastases and a great deal of ascites. The patient ultimately died 14 months after the operation.

  8. Transit timing analysis of CoRoT-1b

    CERN Document Server

    Csizmadia, Sz; Barge, P; Agol, E; Aigrain, S; Alonso, R; Almenara, J M; Bonomo, A S; Borde, P; Bouchy, F; Cabrera, J; Deeg, H J; De la Reza, R; Deleuil, M; Dvorak, R; Erikson, A; Guenther, E W; Fridlund, M; Gondoin, P; Guillot, T; Hatzes, A; Jorda, L; Lammer, H; Lázaro, C; Leger, A; Llebaria, A; Magain, P; Moutou, C; Ollivier, M; Paetzold, M; Queloz, D; Rauer, H; Rouan, D; Schneider, J; Wuchterl, G; Gandolfi, D

    2009-01-01

    CoRoT, the pioneer space-based transit search, steadily provides thousands of high-precision light curves with continuous time sampling over periods of up to 5 months. The transits of a planet perturbed by an additional object are not strictly periodic. By studying the transit timing variations (TTVs), additional objects can be detected in the system. A transit timing analysis of CoRoT-1b is carried out to constrain the existence of additional planets in the system. We used data obtained by an improved version of the CoRoT data pipeline (version 2.0). Individual transits were fitted to determine the mid-transit times, and we analyzed the derived $O-C$ diagram. N-body integrations were used to place limits on secondary planets. No periodic timing variations with a period shorter than the observational window (55 days) are found. The presence of an Earth-mass Trojan is not likely. A planet of mass greater than $\\sim 1$ Earth mass can be ruled out by the present data if the object is in a 2:1 (exterior) mean mot...

  9. Main-Belt Comet P/2012 T1 (PANSTARRS)

    CERN Document Server

    Hsieh, Henry H; Novakovic, Bojan; Yang, Bin; Haghighipour, Nader; Micheli, Marco; Denneau, Larry; Fitzsimmons, Alan; Jedicke, Robert; Kleyna, Jan; Veres, Peter; Wainscoat, Richard J; Ansdell, Megan; Elliott, Garrett T; Keane, Jacqueline V; Meech, Karen J; Moskovitz, Nicholas A; Riesen, Timm E; Sheppard, Scott S; Sonnett, Sarah; Tholen, David J; Urban, Laurie; Kaiser, Nick; Chambers, K C; Burgett, William S; Magnier, Eugene A; Morgan, Jeffrey S; Price, Paul A

    2013-01-01

    We present initial results from observations and numerical analyses aimed at characterizing main-belt comet P/2012 T1 (PANSTARRS). Optical monitoring observations were made between October 2012 and February 2013 using the University of Hawaii 2.2 m telescope, the Keck I telescope, the Baade and Clay Magellan telescopes, Faulkes Telescope South, the Perkins Telescope at Lowell Observatory, and the Southern Astrophysical Research (SOAR) telescope. The object's intrinsic brightness approximately doubles from the time of its discovery in early October until mid-November and then decreases by ~60% between late December and early February, similar to photometric behavior exhibited by several other main-belt comets and unlike that exhibited by disrupted asteroid (596) Scheila. We also used Keck to conduct spectroscopic searches for CN emission as well as absorption at 0.7 microns that could indicate the presence of hydrated minerals, finding an upper limit CN production rate of QCN100 Myr and is unlikely to be a rec...

  10. The secondary eclipse of CoRoT-1b

    CERN Document Server

    Alonso, R; Aigrain, S; Auvergne, M; Baglin, A; Barbieri, M; Barge, P; Bonomo, A S; Borde, P; Bouchy, F; Chaintreuil, S; De la Reza, R; Deeg, H J; Deleuil, M; Dvorak, R; Erikson, A; Fridlund, M; Fialho, F; Gondoin, P; Guillot, T; Hatzes, A; Jorda, L; Lammer, H; Léger, A; Llebaria, A; Magain, P; Mazeh, T; Moutou, C; Ollivier, M; Patzold, M; Pont, F; Queloz, D; Rauer, H; Rouan, D; Schneider, J; Wuchterl, G

    2009-01-01

    The transiting planet CoRoT-1b is thought to belong to the pM-class of planets, in which the thermal emission dominates in the optical wavelengths. We present a detection of its secondary eclipse in the CoRoT white channel data, whose response function goes from ~400 to ~1000 nm. We used two different filtering approaches, and several methods to evaluate the significance of a detection of the secondary eclipse. We detect a secondary eclipse centered within 20 min at the expected times for a circular orbit, with a depth of 0.016+/-0.006%. The center of the eclipse is translated in a 1-sigma upper limit to the planet's eccentricity of ecosomega<0.014. Under the assumption of a zero Bond Albedo and blackbody emission from the planet, it corresponds to a T_{CoRoT}=2330 +120-140 K. We provide the equilibrium temperatures of the planet as a function of the amount of reflected light. If the planet is in thermal equilibrium with the incident flux from the star, our results imply an inefficient transport mechanism ...

  11. Comparison of T1-weighted fast spin-echo and T1-weighted fluid-attenuated inversion recovery images of the lumbar spine at 3.0 Tesla

    Energy Technology Data Exchange (ETDEWEB)

    Lavdas, Eleftherios; Vlychou, Marianna; Arikidis, Nikos; Kapsalaki, Eftychia; Roka, Violetta; Fezoulidis, Ioannis V. (Dept. of Radiology, Univ. Hospital of Larissa, Medical School of Thessaly, Mezourlo (Greece)), e-mail: mvlychou@med.uth.gr

    2010-04-15

    Background: T1-weighted fluid-attenuated inversion recovery (FLAIR) sequence has been reported to provide improved contrast between lesions and normal anatomical structures compared to T1-weighted fast spin-echo (FSE) imaging at 1.5T regarding imaging of the lumbar spine. Purpose: To compare T1-weighted FSE and fast T1-weighted FLAIR imaging in normal anatomic structures and degenerative and metastatic lesions of the lumbar spine at 3.0T. Material and Methods: Thirty-two consecutive patients (19 females, 13 males; mean age 44 years, range 30-67 years) with lesions of the lumbar spine were prospectively evaluated. Sagittal images of the lumbar spine were obtained using T1-weighted FSE and fast T1-weighted FLAIR sequences. Both qualitative and quantitative analyses measuring the signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), and relative contrast (ReCon) between degenerative and metastatic lesions and normal anatomic structures were conducted, comparing these sequences. Results: On quantitative evaluation, SNRs of cerebrospinal fluid (CSF), nerve root, and fat around the root of fast T1-weighted FLAIR imaging were significantly lower than those of T1-weighted FSE images (P<0.001). CNRs of normal spinal cord/CSF and disc herniation/ CSF for fast T1-weighted FLAIR images were significantly higher than those for T1-weighted FSE images (P<0.001). ReCon of normal spinal cord/CSF, disc herniation/CSF, and vertebral lesions/CSF for fast T1-weighted FLAIR images were significantly higher than those for T1-weighted FSE images (P<0.001). On qualitative evaluation, it was found that CSF nulling and contrast at the spinal cord (cauda equina)/CSF interface for T1-weighted FLAIR images were significantly superior compared to those for T1-weighted FSE images (P<0.001), and the disc/spinal cord (cauda equina) interface was better for T1-weighted FLAIR images (P<0.05). Conclusion: The T1-weighted FLAIR sequence may be considered as the preferred lumbar spine imaging

  12. Functional lung MRI in chronic obstructive pulmonary disease: comparison of T1 mapping, oxygen-enhanced T1 mapping and dynamic contrast enhanced perfusion.

    Directory of Open Access Journals (Sweden)

    Bertram J Jobst

    Full Text Available Monitoring of regional lung function in interventional COPD trials requires alternative endpoints beyond global parameters such as FEV1. T1 relaxation times of the lung might allow to draw conclusions on tissue composition, blood volume and oxygen fraction. The aim of this study was to evaluate the potential value of lung Magnetic resonance imaging (MRI with native and oxygen-enhanced T1 mapping for the assessment of COPD patients in comparison with contrast enhanced perfusion MRI.20 COPD patients (GOLD I-IV underwent a coronal 2-dimensional inversion recovery snapshot flash sequence (8 slices/lung at room air and during inhalation of pure oxygen, as well as dynamic contrast-enhanced first-pass perfusion imaging. Regional distribution of T1 at room air (T1, oxygen-induced T1 shortening (ΔT1 and peak enhancement were rated by 2 chest radiologists in consensus using a semi-quantitative 3-point scale in a zone-based approach.Abnormal T1 and ΔT1 were highly prevalent in the patient cohort. T1 and ΔT1 correlated positively with perfusion abnormalities (r = 0.81 and r = 0.80; p&0.001, and with each other (r = 0.80; p<0.001. In GOLD stages I and II ΔT1 was normal in 16/29 lung zones with mildly abnormal perfusion (15/16 with abnormal T1. The extent of T1 (r = 0.45; p<0.05, ΔT1 (r = 0.52; p<0.05 and perfusion abnormalities (r = 0.52; p<0.05 showed a moderate correlation with GOLD stage.Native and oxygen-enhanced T1 mapping correlated with lung perfusion deficits and severity of COPD. Under the assumption that T1 at room air correlates with the regional pulmonary blood pool and that oxygen-enhanced T1 reflects lung ventilation, both techniques in combination are principally suitable to characterize ventilation-perfusion imbalance. This appears valuable for the assessment of regional lung characteristics in COPD trials without administration of i.v. contrast.

  13. Effect of ionizing radiation on the human brain: white matter and gray matter T1 in pediatric brain tumor patients treated with conformal radiation therapy.

    Science.gov (United States)

    Steen, R G; Koury B S, M; Granja, C I; Xiong, X; Wu, S; Glass, J O; Mulhern, R K; Kun, L E; Merchant, T E

    2001-01-01

    To test a hypothesis that fractionated radiation therapy (RT) to less than 60 Gy is associated with a dose-related change in the spin-lattice relaxation time (T1) of normal brain tissue, and that such changes are detectable by quantitative MRI (qMRI). Each of 21 patients received a qMRI examination before treatment, and at several time points during and after RT. A map of brain T1 was calculated and segmented into white matter and gray matter at each time point. The RT isodose contours were then superimposed upon the T1 map, and changes in brain tissue T1 were analyzed as a function of radiation dose and time following treatment. We used a mixed-model analysis to analyze the longitudinal trend in brain T1 from the start of RT to 1 year later. Predictive factors evaluated included patient age and clinical variables, such as RT dose, time since treatment, and the use of an imaging contrast agent. In white matter (WM), a dose level of greater than 20 Gy was associated with a dose-dependent decrease in T1 over time, which became significant about 3 months following treatment. In gray matter (GM), there was no significant change in T1 over time, as a function of RT doses effect on brain T1. Results suggest that T1 mapping may be sensitive to radiation-related changes in human brain tissue T1. WM T1 appears to be unaffected by RT at doses less than approximately 20 Gy; GM T1 does not change at doses less than 60 Gy. However, tumor appears to have an effect upon adjacent GM, even before treatment. Conformal RT may offer a substantial benefit to the patient, by minimizing the volume of normal brain exposed to greater than 20 Gy.

  14. VLT transit and occultation photometry for the bloated planet CoRoT-1b

    OpenAIRE

    Gillon, Michaël; Demory, B. -O.; Triaud, A. H. M. J.; Barman, T; Hebb, L.; Montalban Iglesias, Josefa; Maxted, P.; Queloz, D; Deleuil, M.; Magain, Pierre

    2009-01-01

    We present VLT eclipse photometry for the giant planet CoRoT-1b. We observed a transit in the R-band filter and an occultation in a narrow filter centered on 2.09 microns. Our analysis of this new photometry and published radial velocities, in combination with stellar-evolutionary modeling, leads to a planetary mass and radius of 1.07 (+0.13,-0.18) M_Jup and 1.45 (+0.07,-0.13) R_Jup, confirming the very low density previously deduced from CoRoT photometry. The large occultation depth that we ...

  15. Physical Activity and Spatial Differences in Medial Knee T1rho and T2 Relaxation Times in Knee Osteoarthritis

    Science.gov (United States)

    KUMAR, DEEPAK; SOUZA, RICHARD B.; SINGH, JUSTIN; CALIXTO, NATHANIEL E.; NARDO, LORENZO; LINK, THOMAS M.; LI, XIAOJUAN; MAJUMDAR, SHARMILA

    2015-01-01

    STUDY DESIGN Cross-sectional. OBJECTIVES To investigate the association between knee loading–related osteoarthritis (OA) risk factors (obesity, malalignment, and physical activity) and medial knee laminar (superficial and deep) T1rho and T2 relaxation times. BACKGROUND The interaction of various modifiable loading-related knee risk factors and cartilage health in knee OA is currently not well known. METHODS Participants with and without knee OA (n = 151) underwent magnetic resonance imaging at 3 T for superficial and deep cartilage T1rho and T2 magnetic resonance relaxation times in the medial femur (MF) and medial tibia (MT). Other variables included radiographic Kellgren-Lawrence (KL) grade, alignment, pain and symptoms using the Knee injury and Osteoarthritis Outcome Score, and physical activity using the International Physical Activity Questionnaire (IPAQ). Individuals with a KL grade of 4 were excluded. Group differences were calculated using 1-way analysis of variance, adjusting for age and body mass index. Linear regression models were created with age, sex, body mass index, alignment, KL grade, and the IPAQ scores to predict the laminar T1rho and T2 times. RESULTS Total IPAQ scores were the only significant predictors among the loading-related variables for superficial MF T1rho (P = .005), deep MT T1rho (P = .026), and superficial MF T2 (P = .049). Additionally, the KL grade predicted the superficial MF T1rho (P = .023) and deep MT T1rho (P = .022). CONCLUSION Higher physical activity levels and worse radiographic severity of knee OA, but not obesity or alignment, were associated with worse cartilage composition. PMID:25353261

  16. Evaluation of bone marrow by opposed phase T1-weighted images and enhanced MR imaging

    Energy Technology Data Exchange (ETDEWEB)

    Amano, Yasuo; Tanabe, Yoshihiro; Miyashita, Tsuguhiro; Hayashi, Hiromitsu; Horiuchi, Junichi; Nomura, Takeo; Kumazaki, Tatsuo (Nippon Medical School, Tokyo (Japan))

    1994-09-01

    We investigated bone marrow in a control group, cases of aplastic anemia and post-irradiation patients by examining T1-weighted (T1W1), short T1 inversion recovery (STIR), opposed phase T1W1 (op-T1W1) and Gd-DTPA enhanced op-T1W1 images obtained by 0.5 T MRI. Bone marrow was classified into four types based on MR findings. Normal marrow showed low intensity on op-T1W1 and STIR images without enhancement (I). Fatty marrow, which showed high intensity on T1W1 and op-T1W1 images was observed in aplastic anemia and post-irradiation patients (II). Hematopoietic marrow (III) showed low intensity on op-T1W1 and enhanced, while active hematopoietic marrow (IV) revealed high intensity on both STIR and op-T1W1 images and was enhanced following Gd-DTPA infusion. Aplastic anemia of moderate grade included types II, III and IV. Enhanced MR was needed to differentiate between types I and III since both types showed low intensity on op-T1W1 images. Furthermore, type IV was considered as hyperplastic compared with type III. Enhanced MR and op-T1W1 images were useful in evaluating hematopoiesis of bone marrow. (author).

  17. Review. The mammalian proton-coupled peptide cotransporter PepT1: sitting on the transporter-channel fence?

    Science.gov (United States)

    Meredith, David

    2009-01-27

    The proton-coupled di- and tripeptide transporter PepT1 (SLC15a1) is the major route by which dietary nitrogen is taken up from the small intestine, as well as being the route of entry for important therapeutic (pro)drugs such as the beta-lactam antibiotics, angiotensin-converting enzyme inhibitors and antiviral and anti-cancer agents. PepT1 is a member of the major facilitator superfamily of 12 transmembrane domain transporter proteins. Expression studies in Xenopus laevis on rabbit PepT1 that had undergone site-directed mutagenesis of a conserved arginine residue (arginine282 in transmembrane domain 7) to a glutamate revealed that this residue played a role in the coupling of proton and peptide transport and prevented the movement of non-coupled ions during the transporter cycle. Mutations of arginine282 to other non-positive residues did not uncouple proton-peptide cotransport, but did allow additional ion movements when substrate was added. By contrast, mutations to positive residues appeared to function the same as wild-type. These findings are discussed in relation to the functional role that arginine282 may play in the way PepT1 operates, together with structural information from the homology model of PepT1 based on the Escherichia coli lactose permease crystal structure.

  18. Systematic review on the surgical treatment for T1 gallbladder cancer

    Institute of Scientific and Technical Information of China (English)

    Seung Eun Lee; Jin-Young Jang; Chang-Sup Lim; Mee Joo Kang; Sun-Whe Kim

    2011-01-01

    AIM: To evaluate the efficacy of simple and extended cholecystectomy for mucosa (T1a) or muscularis (T1b)gallbladder (GB) cancer.METHODS: Original studies on simple and extended cholecystectomy for T1a or T1b GB cancer were searched from MEDLINE (PubMed), Cochrane Library, EMBase,and CancerLit using the search terms of GB, cancer/carcinoma/tumor/neoplasm.RESULTS: Twenty-nine out of the 2312 potentially relevant publications met the eligibility criteria. Of the 1266patients with GB cancer included in the publications,706 (55.8%) and 560 (44.2%) had T1a and T1b GB cancer, respectively. Simple cholecystectomy for T1a and T1b GB cancer was performed in 590 (83.6%) and 375 (67.0%) patients, respectively (P < 0.01). In most series, the treatment of choice was simple cholecystectomy for T1a GB cancer patients with a 5-year survival rate of 100%. Lymph node metastasis was detected in 10.9% of the T1b GB cancer patients and in 1.8% of the T1a GB cancer patients, respectively (P < 0.01).Eight patients (1.1%) with T1a GB cancer and 52 patients (9.3%) with T1b GB cancer died of recurrent GB cancer (P < 0.01).CONCLUSION: Simple cholecystectomy represents the adequate treatment of T1a GB cancer. There is no definite evidence that extended cholecystectomy is advantageous over simple cholecystectomy for T1b GB cancer.

  19. Decoding of exon splicing patterns in the human RUNX1-RUNX1T1 fusion gene.

    Science.gov (United States)

    Grinev, Vasily V; Migas, Alexandr A; Kirsanava, Aksana D; Mishkova, Olga A; Siomava, Natalia; Ramanouskaya, Tatiana V; Vaitsiankova, Alina V; Ilyushonak, Ilia M; Nazarov, Petr V; Vallar, Laurent; Aleinikova, Olga V

    2015-11-01

    The t(8;21) translocation is the most widespread genetic defect found in human acute myeloid leukemia. This translocation results in the RUNX1-RUNX1T1 fusion gene that produces a wide variety of alternative transcripts and influences the course of the disease. The rules of combinatorics and splicing of exons in the RUNX1-RUNX1T1 transcripts are not known. To address this issue, we developed an exon graph model of the fusion gene organization and evaluated its local exon combinatorics by the exon combinatorial index (ECI). Here we show that the local exon combinatorics of the RUNX1-RUNX1T1 gene follows a power-law behavior and (i) the vast majority of exons has a low ECI, (ii) only a small part is represented by "exons-hubs" of splicing with very high ECI values, and (iii) it is scale-free and very sensitive to targeted skipping of "exons-hubs". Stochasticity of the splicing machinery and preferred usage of exons in alternative splicing can explain such behavior of the system. Stochasticity may explain up to 12% of the ECI variance and results in a number of non-coding and unproductive transcripts that can be considered as a noise. Half-life of these transcripts is increased due to the deregulation of some key genes of the nonsense-mediated decay system in leukemia cells. On the other hand, preferred usage of exons may explain up to 75% of the ECI variability. Our analysis revealed a set of splicing-related cis-regulatory motifs that can explain "attractiveness" of exons in alternative splicing but only when they are considered together. Cis-regulatory motifs are guides for splicing trans-factors and we observed a leukemia-specific profile of expression of the splicing genes in t(8;21)-positive blasts. Altogether, our results show that alternative splicing of the RUNX1-RUNX1T1 transcripts follows strict rules and that the power-law component of the fusion gene organization confers a high flexibility to this process.

  20. Ultra-low field T1 vs. T1rho at 3T and 7T: study of rotationally immobilized protein gels and animal brain tissues

    Science.gov (United States)

    Dong, Hui; Inglis, Ben; Barr, Ian; Clarke, John

    2015-03-01

    Clinical magnetic resonance imaging (MRI) machines operating in static fields of typically 1.5 T or 3 T can capture information on slow molecular dynamics utilizing the so-called T1rho technique. This technique, in which a radiofrequency (RF) spin-lock field is applied with microtesla amplitude, has been used, for example, to determine the onset time of stroke in studies on rats. The long RF pulse, however, may exceed the specific absorption rate (SAR) limit, putting subjects at risk. Ultra-low-field (ULF) MRI, based on Superconducting Quantum Interference Devices (SQUIDs), directly detects proton signals at a static magnetic field of typically 50-250 μT. Using our ULF MRI system with adjustable static field of typically 55 to 240 μT, we systematically measured the T1 and T2 dispersion profiles of rotationally immobilized protein gels (bovine serum albumin), ex vivo pig brains, and ex vivo rat brains with induced stroke. Comparing the ULF results with T1rho dispersion obtained at 3 T and 7 T, we find that the degree of protein immobilization determines the frequency-dependence of both T1 and T1rho. Furthermore, T1rho and ULF T1 show similar results for stroke, suggesting that ULF MRI may be used to image traumatic brain injury with negligible SAR. This research was supported by the Henry H. Wheeler, Jr. Brain Imaging Center and the Donaldson Trust.

  1. T1rho mapping of entire femoral cartilage using depth- and angle-dependent analysis

    Energy Technology Data Exchange (ETDEWEB)

    Nozaki, Taiki; Kaneko, Yasuhito; Yu, Hon J.; Yoshioka, Hiroshi [University of California Irvine, Department of Radiological Sciences, Orange, CA (United States); Kaneshiro, Kayleigh [University of California Irvine, School of Medicine, Irvine, CA (United States); Schwarzkopf, Ran [University of California Irvine, Department of Orthopedic Surgery, Irvine, CA (United States); Hara, Takeshi [Gifu University Graduate School of Medicine, Department of Intelligent Image Information, Division of Regeneration and Advanced Medical Sciences, Gifu (Japan)

    2016-06-15

    To create and evaluate normalized T1rho profiles of the entire femoral cartilage in healthy subjects with three-dimensional (3D) angle- and depth-dependent analysis. T1rho images of the knee from 20 healthy volunteers were acquired on a 3.0-T unit. Cartilage segmentation of the entire femur was performed slice-by-slice by a board-certified radiologist. The T1rho depth/angle-dependent profile was investigated by partitioning cartilage into superficial and deep layers, and angular segmentation in increments of 4 over the length of segmented cartilage. Average T1rho values were calculated with normalized T1rho profiles. Surface maps and 3D graphs were created. T1rho profiles have regional and depth variations, with no significant magic angle effect. Average T1rho values in the superficial layer of the femoral cartilage were higher than those in the deep layer in most locations (p < 0.05). T1rho values in the deep layer of the weight-bearing portions of the medial and lateral condyles were lower than those of the corresponding non-weight-bearing portions (p < 0.05). Surface maps and 3D graphs demonstrated that cartilage T1rho values were not homogeneous over the entire femur. Normalized T1rho profiles from the entire femoral cartilage will be useful for diagnosing local or early T1rho abnormalities and osteoarthritis in clinical applications. (orig.)

  2. Silibinin and Paclitaxel Cotreatment Significantly Suppress the Activity and Lung Metastasis of Triple Negative 4T1 Mammary Tumor Cell in Mice

    Directory of Open Access Journals (Sweden)

    Bing-Ying Ho

    2012-10-01

    Full Text Available The in vitro and in vivo bioactivities of silibinin (SB, paclitaxel (PTX and SB and PTX in combination (SB+PTX against murine metastatic mammary 4T1 cancer cell line were investigated. Isobologram and combination index (CI analyses showed that SB and PTX can function synergistically in the inhibition of 4T1 cell proliferation with a CI value<1. Both SB and PTX alone or SB+PTX treatment inhibited 4T1 cell migration and motility possibly through downregulation of the serpin protease nexin-1 (PN-1 and N-cadherin expression, inhibition of matrix metalloprotease (MMP-9 activity, and upregulation of E-cadherin. Flow cytometry and Western blot analyses demonstrated that both drugs deregulated cell-cycle mediators and induced apoptosis in 4T1 cells. A real-time in vivo bioluminescence imaging system to monitor the breast cancer cell metastasis in syngeneic BALB/c mice was established using a stable 4T1pGL−COX−2/Luc cell clone carrying a COX-2 promoter driven-luciferase reporter gene. In vivo study using the allograft 4T1pGL−COX−2/Luc metastatic mouse model indicated that SB co-treated with PTX can significantly suppress lung metastasis of 4T1 cells likely through inhibiting cell proliferation and angiogenesis. Together, this study demonstrates that SB could act synergistically with PTX in 4T1 cells, providing a therapeutic option for highly metastatic triple negative breast cancer.

  3. Application of Schrödinger equation to study the tunnelling dynamics of proton transfer in the hydrogen bond of 2,5-dinitrobenzoic acid: proton T1 T1rho, and deuteron T1 relaxation methods.

    Science.gov (United States)

    Latanowicz, L; Medycki, W

    2007-02-22

    Temperature measurements of proton T1 (24.7 MHz), deuteron (deuterated hydroxyl group) T1 (55.2 MHz), and proton T1(rho) (B1 = 9 G) spin-lattice relaxation times of 2,5-dinitrobenzoic acid have been performed. An analysis of present experimental data together with previously published proton T1 (55.2 MHz) data has revealed the following molecular motions: proton/deuteron transfer in the hydrogen bond and two-site hopping of the whole dimer. It is shown that the proton-transfer dynamics are characterized by two correlation times tau(ov) and tau(tu), describing two fundamentally different motional processes, namely, thermally activated jumps over the barrier and tunneling through the barrier. The temperature dependence of 1/tau(tu) is the solution of Schrödinger's equation, which also yields the temperature T(tun), where begins the tunnel pathway for proton transfer. A new equation for the spectral density function of complex motion consisting of the three motions is derived. The third motion (two-site hopping of the whole dimer characterized by tau(lib) correlation time) is responsible for a proton T1(rho) minimum in high temperatures, just below the melting point. Such a minimum is not reached by T1 temperature dependencies. The minimum of T1(rho) assigned to the classical hopping of a hydrogen-bonded proton occurs in the same low-temperature regime in which the flattening of the temperature dependencies of T1 points to the dominance of incoherent tunneling. This experimental fact denies the known theories predicting the intermediate temperature regime where a smooth transition between classical and quantum tunneling dynamics is expected. The fit of the derived theoretical equations to the experimental data T1(rho) and T1 is satisfactory. The correlation times obtained for deuterons indicate deuteron-transfer dynamics much slower than proton-transfer dynamics. It is concluded that the classical proton transfer takes place over the whole temperature regime, while

  4. Knee Cartilage Thickness, T1ρ and T2 Relaxation Time Are Related to Articular Cartilage Loading in Healthy Adults

    Science.gov (United States)

    Van Rossom, Sam; Smith, Colin Robert; Zevenbergen, Lianne; Thelen, Darryl Gerard; Vanwanseele, Benedicte; Van Assche, Dieter; Jonkers, Ilse

    2017-01-01

    Cartilage is responsive to the loading imposed during cyclic routine activities. However, the local relation between cartilage in terms of thickness distribution and biochemical composition and the local contact pressure during walking has not been established. The objective of this study was to evaluate the relation between cartilage thickness, proteoglycan and collagen concentration in the knee joint and knee loading in terms of contact forces and pressure during walking. 3D gait analysis and MRI (3D-FSE, T1ρ relaxation time and T2 relaxation time sequence) of fifteen healthy subjects were acquired. Experimental gait data was processed using musculoskeletal modeling to calculate the contact forces, impulses and pressure distribution in the tibiofemoral joint. Correlates to local cartilage thickness and mean T1ρ and T2 relaxation times of the weight-bearing area of the femoral condyles were examined. Local thickness was significantly correlated with local pressure: medial thickness was correlated with medial condyle contact pressure and contact force, and lateral condyle thickness was correlated with lateral condyle contact pressure and contact force during stance. Furthermore, average T1ρ and T2 relaxation time correlated significantly with the peak contact forces and impulses. Increased T1ρ relaxation time correlated with increased shear loading, decreased T1ρ and T2 relaxation time correlated with increased compressive forces and pressures. Thicker cartilage was correlated with higher condylar loading during walking, suggesting that cartilage thickness is increased in those areas experiencing higher loading during a cyclic activity such as gait. Furthermore, the proteoglycan and collagen concentration and orientation derived from T1ρ and T2 relaxation measures were related to loading. PMID:28076431

  5. VLT transit and occultation photometry for the bloated planet CoRoT-1b

    CERN Document Server

    Gillon, M; Triaud, A H M J; Barman, T; Hebb, L; Montalban, J; Maxted, P F L; Queloz, D; Deleuil, M; Magain, P

    2009-01-01

    We present VLT eclipse photometry for the giant planet CoRoT-1b. We observed a transit in the R-band filter and an occultation in a narrow filter centered on 2.09 microns. Our analysis of this new photometry and published radial velocities, in combination with stellar-evolutionary modeling, leads to a planetary mass and radius of 1.07 (+0.13,-0.18) M_Jup and 1.45 (+0.07,-0.13) R_Jup, confirming the very low density previously deduced from CoRoT photometry. The large occultation depth that we measure at 2.09 microns (0.278 (+0.043,-0.066) %) is consistent with thermal emission and is better reproduced by an atmospheric model with no redistribution of the absorbed stellar flux to the night side of the planet.

  6. Artifacts correction for T1rho imaging with constant amplitude spin-lock

    Science.gov (United States)

    Chen, Weitian

    2017-01-01

    T1rho imaging with constant amplitude spin-lock is prone to artifacts in the presence of B1 RF and B0 field inhomogeneity. Despite significant technological progress, improvements on the robustness of constant amplitude spin-lock are necessary in order to use it for routine clinical practice. This work proposes methods to simultaneously correct for B1 RF and B0 field inhomogeneity in constant amplitude spin-lock. By setting the maximum B1 amplitude of the excitation adiabatic pulses equal to the expected constant amplitude spin-lock frequency, the spins become aligned along the effective field throughout the spin-lock process. This results in T1rho-weighted images free of artifacts, despite the spatial variation of the effective field caused by B1 RF and B0 field inhomogeneity. When the pulse is long, the relaxation effect during the adiabatic half passage may result in a non-negligible error in the mono-exponential relaxation model. A two-acquisition approach is presented to solve this issue. Simulation, phantom, and in-vivo scans demonstrate the proposed methods achieve superior image quality compared to existing methods, and that the two-acquisition method is effective in resolving the relaxation effect during the adiabatic half passage.

  7. Soft Dynamics simulation. 2. Elastic spheres undergoing a T(1) process in a viscous fluid.

    Science.gov (United States)

    Rognon, P; Gay, C

    2009-11-01

    Robust empirical constitutive laws for granular materials in air or in a viscous fluid have been expressed in terms of timescales based on the dynamics of a single particle. However, some behaviours such as viscosity bifurcation or shear localization, observed also in foams, emulsions, and block copolymer cubic phases, seem to involve other micro-timescales which may be related to the dynamics of local particle reorganizations. In the present work, we consider a T(1) process as an example of a rearrangement. Using the Soft Dynamics simulation method introduced in the first paper of this series, we describe theoretically and numerically the motion of four elastic spheres in a viscous fluid. Hydrodynamic interactions are described at the level of lubrication (Poiseuille squeezing and Couette shear flow) and the elastic deflection of the particle surface is modeled as Hertzian. The duration of the simulated T(1) process can vary substantially as a consequence of minute changes in the initial separations, consistently with predictions. For the first time, a collective behaviour is thus found to depend on a parameter other than the typical volume fraction of particles.

  8. Tetrandrine Suppresses Cancer Angiogenesis and Metastasis in 4T1 Tumor Bearing Mice

    Directory of Open Access Journals (Sweden)

    Jian-Li Gao

    2013-01-01

    Full Text Available Metastasis remains the most deadly aspect of cancer and still evades direct treatment. Thus, there is a great need to develop new treatment regimens to suppress tumor cells that have escaped surgical removal or that may have already disseminated. We have found that tetrandrine (TET exhibits anticolon cancer activity. Here, we investigate the inhibition effect of TET to breast cancer metastasis, angiogenesis and its molecular basis underlying TET’s anticancer activity. We compare TET with chemotherapy drug doxorubicin in 4T1 tumor bearing BALB/c mice model and find that TET exhibits an anticancer metastatic and antiangiogenic activities better than those of doxorubicin. The lung metastatic sites were decreased by TET, which is confirmed by bioluminescence imaging in vivo. On the other hand, laser doppler perfusion imaging (LDI was used for measuring the blood flow of tumor in 4T1-tumor bearing mice. As a result, the local blood perfusion of tumor was markedly decreased by TET after 3 weeks. Mechanistically, TET treatment leads to a decrease in p-ERK level and an increase in NF-κB levels in HUVECs. TET also regulated metastatic and angiogenic related proteins, including vascular endothelial growth factor, hypoxia-inducible factor-1α, integrin β5, endothelial cell specific molecule-1, and intercellular adhesion molecule-1 in vivo.

  9. Self-attraction effect and correction on the T-1 absolute gravimeter

    Science.gov (United States)

    Li, Z.; Hu, H.; Wu, K.; Li, G.; Wang, G.; Wang, L. J.

    2015-12-01

    The self-attraction effect (SAE) in an absolute gravimeter is a kind of systematic error due to the gravitation of the instrument to the falling object. This effect depends on the mass distribution of the gravimeter, and is estimated to be a few microgals (1 μGal  =  10-8 m s-2) for the FG5 gravimeter. In this paper, the SAE of a home-made T-1 absolute gravimeter is analyzed and calculated. Most of the stationary components, including the dropping chamber, the laser interferometer, the vibration isolation device and two tripods, are finely modelled, and the related SAEs are computed. In addition, the SAE of the co-falling carriage inside the dropping chamber is carefully calculated because the distance between the falling object and the co-falling carriage varies during the measurement. In order to get the correction of the SAE, two different methods are compared. One is to linearize the SAE curve, the other one is to calculate the perturbed trajectory. The results from these two methods agree with each other within 0.01 μGal. With an uncertainty analysis, the correction of the SAE of the T-1 gravimeter is estimated to be (-1.9  ±  0.1) μGal.

  10. Fully automatic detection of deep white matter T1 hypointense lesions in multiple sclerosis

    Science.gov (United States)

    Spies, Lothar; Tewes, Anja; Suppa, Per; Opfer, Roland; Buchert, Ralph; Winkler, Gerhard; Raji, Alaleh

    2013-12-01

    A novel method is presented for fully automatic detection of candidate white matter (WM) T1 hypointense lesions in three-dimensional high-resolution T1-weighted magnetic resonance (MR) images. By definition, T1 hypointense lesions have similar intensity as gray matter (GM) and thus appear darker than surrounding normal WM in T1-weighted images. The novel method uses a standard classification algorithm to partition T1-weighted images into GM, WM and cerebrospinal fluid (CSF). As a consequence, T1 hypointense lesions are assigned an increased GM probability by the standard classification algorithm. The GM component image of a patient is then tested voxel-by-voxel against GM component images of a normative database of healthy individuals. Clusters (≥0.1 ml) of significantly increased GM density within a predefined mask of deep WM are defined as lesions. The performance of the algorithm was assessed on voxel level by a simulation study. A maximum dice similarity coefficient of 60% was found for a typical T1 lesion pattern with contrasts ranging from WM to cortical GM, indicating substantial agreement between ground truth and automatic detection. Retrospective application to 10 patients with multiple sclerosis demonstrated that 93 out of 96 T1 hypointense lesions were detected. On average 3.6 false positive T1 hypointense lesions per patient were found. The novel method is promising to support the detection of hypointense lesions in T1-weighted images which warrants further evaluation in larger patient samples.

  11. ANALISIS PERBEDAAN CITRA MRI BRAIN PADA SEKUENT1SE DAN T1FLAIR

    Directory of Open Access Journals (Sweden)

    Nursama Heru Apriantoro

    2015-10-01

    Full Text Available MRI adalah bagian dari ilmu kedokteran untuk mediagnosa kelainan organ dengan memanfaatkan medan magnet dan pergerakan proton atom hidrogen. Salah satu pemeriksaan MRI adalah pemeriksaan brain. Pemeriksaan MRI brain dapat dilakukan T1 weighted image Spin Echo (T1 SE atau T1 Fluid Attenuated Inversion Recovery (T1 FLAIR. Kajian dilakukan untuk menentukan perbedaan T1 SE dan T1 FLAIR dari segi citra berdasarkan nilai Rasio Signal terhadap Noise (SNR dengan MRI GE Type Signa HD xt 1.5 Tesla. Penelitian menggunakan pendekatan kuantitatif.  20 pasien  telah diambil pada pemeriksaan MRI brain pada potongan axial, dengan parameter T1 SE potongan axial dengan parameter Time Repetition (TR 700 ms, Time Echo (TE 20 ms, Field of View (FOV 240 mm, Slice Thickness 5,0 mm, Spacing 1,0 mm, Number of Excitations (NEX 1, Phase 224, dan total slice 20. T1 FLAIR  parameter TR 3000 ms, TE 13,9 ms, TI 920 ms, FOV 240 mm, slice thickness 5,0 mm, spacing 1,0 mm,   NEX 1, phase 224, dan total slice 20. SNR dihitung pada anatomi brain meliputi CSF (Cerebro Spinal Fluid, White Matter dan Gray Matter. Hasil penelitian kedua sequence tersebut menunjukkan bahwa sequence T1 SE lebih baik daripada sequence T1 FLAIR.

  12. Structural basis for perception of diverse chemical substances by T1r taste receptors.

    Science.gov (United States)

    Nuemket, Nipawan; Yasui, Norihisa; Kusakabe, Yuko; Nomura, Yukiyo; Atsumi, Nanako; Akiyama, Shuji; Nango, Eriko; Kato, Yukinari; Kaneko, Mika K; Takagi, Junichi; Hosotani, Maiko; Yamashita, Atsuko

    2017-05-23

    The taste receptor type 1 (T1r) family perceives 'palatable' tastes. These receptors function as T1r2-T1r3 and T1r1-T1r3 heterodimers to recognize a wide array of sweet and umami (savory) tastes in sugars and amino acids. Nonetheless, it is unclear how diverse tastes are recognized by so few receptors. Here we present crystal structures of the extracellular ligand-binding domains (LBDs), the taste recognition regions of the fish T1r2-T1r3 heterodimer, bound to different amino acids. The ligand-binding pocket in T1r2LBD is rich in aromatic residues, spacious and accommodates hydrated percepts. Biophysical studies show that this binding site is characterized by a broad yet discriminating chemical recognition, contributing for the particular trait of taste perception. In contrast, the analogous pocket in T1r3LBD is occupied by a rather loosely bound amino acid, suggesting that the T1r3 has an auxiliary role. Overall, we provide a structural basis for understanding the chemical perception of taste receptors.

  13. Sugar-induced cephalic-phase insulin release is mediated by a T1r2+T1r3-independent taste transduction pathway in mice.

    Science.gov (United States)

    Glendinning, John I; Stano, Sarah; Holter, Marlena; Azenkot, Tali; Goldman, Olivia; Margolskee, Robert F; Vasselli, Joseph R; Sclafani, Anthony

    2015-09-01

    Sensory stimulation from foods elicits cephalic phase responses, which facilitate digestion and nutrient assimilation. One such response, cephalic-phase insulin release (CPIR), enhances glucose tolerance. Little is known about the chemosensory mechanisms that activate CPIR. We studied the contribution of the sweet taste receptor (T1r2+T1r3) to sugar-induced CPIR in C57BL/6 (B6) and T1r3 knockout (KO) mice. First, we measured insulin release and glucose tolerance following oral (i.e., normal ingestion) or intragastric (IG) administration of 2.8 M glucose. Both groups of mice exhibited a CPIR following oral but not IG administration, and this CPIR improved glucose tolerance. Second, we examined the specificity of CPIR. Both mouse groups exhibited a CPIR following oral administration of 1 M glucose and 1 M sucrose but not 1 M fructose or water alone. Third, we studied behavioral attraction to the same three sugar solutions in short-term acceptability tests. B6 mice licked more avidly for the sugar solutions than for water, whereas T1r3 KO mice licked no more for the sugar solutions than for water. Finally, we examined chorda tympani (CT) nerve responses to each of the sugars. Both mouse groups exhibited CT nerve responses to the sugars, although those of B6 mice were stronger. We propose that mice possess two taste transduction pathways for sugars. One mediates behavioral attraction to sugars and requires an intact T1r2+T1r3. The other mediates CPIR but does not require an intact T1r2+T1r3. If the latter taste transduction pathway exists in humans, it should provide opportunities for the development of new treatments for controlling blood sugar. Copyright © 2015 the American Physiological Society.

  14. Identification of myocardial diffuse fibrosis by 11 heartbeat MOLLI T 1 mapping: averaging to improve precision and correlation with collagen volume fraction.

    Science.gov (United States)

    Vassiliou, Vassilios S; Wassilew, Katharina; Cameron, Donnie; Heng, Ee Ling; Nyktari, Evangelia; Asimakopoulos, George; de Souza, Anthony; Giri, Shivraman; Pierce, Iain; Jabbour, Andrew; Firmin, David; Frenneaux, Michael; Gatehouse, Peter; Pennell, Dudley J; Prasad, Sanjay K

    2017-06-12

    Our objectives involved identifying whether repeated averaging in basal and mid left ventricular myocardial levels improves precision and correlation with collagen volume fraction for 11 heartbeat MOLLI T 1 mapping versus assessment at a single ventricular level. For assessment of T 1 mapping precision, a cohort of 15 healthy volunteers underwent two CMR scans on separate days using an 11 heartbeat MOLLI with a 5(3)3 beat scheme to measure native T 1 and a 4(1)3(1)2 beat post-contrast scheme to measure post-contrast T 1, allowing calculation of partition coefficient and ECV. To assess correlation of T 1 mapping with collagen volume fraction, a separate cohort of ten aortic stenosis patients scheduled to undergo surgery underwent one CMR scan with this 11 heartbeat MOLLI scheme, followed by intraoperative tru-cut myocardial biopsy. Six models of myocardial diffuse fibrosis assessment were established with incremental inclusion of imaging by averaging of the basal and mid-myocardial left ventricular levels, and each model was assessed for precision and correlation with collagen volume fraction. A model using 11 heart beat MOLLI imaging of two basal and two mid ventricular level averaged T 1 maps provided improved precision (Intraclass correlation 0.93 vs 0.84) and correlation with histology (R (2) = 0.83 vs 0.36) for diffuse fibrosis compared to a single mid-ventricular level alone. ECV was more precise and correlated better than native T 1 mapping. T 1 mapping sequences with repeated averaging could be considered for applications of 11 heartbeat MOLLI, especially when small changes in native T 1/ECV might affect clinical management.

  15. Wettability of Chalk and Argillaceous Sandstones Assessed from T1/T2 Ratio

    DEFF Research Database (Denmark)

    Katika, Konstantina; Saidian, M.; Fabricius, Ida Lykke

    to mineral properties. Thus, longitudinal, T1, and transverse, T2, relaxation times should in principle be similar. However, microscopic magnetic gradients related to minerals can shorten T2 as compared to T1 provided the saturating fluid has high affinity to the solid. We consequently find that the T1/T2...... with water, oil or oil/water at irreducible water saturation. The T1/T2 ratio obtained from T1-T2 maps reflects the T2-shortening. We compare the T1/T2 ratio for the same type of rock, saturated with different fluids. The chalk shows high affinity for water, Berea sandstone has no clear preference for oil...

  16. Difference between Extra- and Intracellular T1 Values of Carboxylic Acids Affects the Quantitative Analysis of Cellular Kinetics by Hyperpolarized NMR

    DEFF Research Database (Denmark)

    Karlsson, Magnus; Jensen, Pernille Rose; Ardenkjær-Larsen, Jan Henrik

    2016-01-01

    Incomplete knowledge of the longitudinal relaxation time constant (T1) leads to incorrect assumptions in quantitative kinetic models of cellular systems, studied by hyperpolarized real-time NMR. Using an assay that measures the intracellular signal of small carboxylic acids in living cells...... on the quantification of intracellular metabolic activity. It is expected that the significantly shorter T1 value of the carboxylic moieties inside cells is a result of macromolecular crowding. An artificial cytosol has been prepared and applied to predict the T1 of other carboxylic acids. We demonstrate the value...

  17. MR T1{rho} as an imaging biomarker for monitoring liver injury progression and regression: an experimental study in rats with carbon tetrachloride intoxication

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Feng; Wang, Yi-Xiang J.; Yuan, Jing; Deng, Min; Ahuja, Anil T. [Chinese University of Hong Kong, Department of Imaging and Interventional Radiology, Prince of Wales Hospital, Hong Kong SAR (China); Wong, Hing Lok [School of Public Health and Primary Care, Prince of Wales Hospital, The Chinese University of Hong Kong, Jockey Club Centre for Osteoporosis Care and Control, Hong Kong SAR (China); Chu, Eagle S.H.; Go, Minnie Y.Y.; Yu, Jun [Chinese University of Hong Kong, Institute of Digestive Disease and Department of Medicine and Therapeutics, Li Ka Shing Institute of Health Sciences, Hong Kong SAR (China); Teng, Gao-Jun [Southeast University, Department of Radiology, Zhongda Hospital, Nanjing (China)

    2012-08-15

    Recently it was shown that the magnetic resonance imaging (MRI) T1{rho} value increased with the severity of liver fibrosis in rats with bile duct ligation. Using a rat carbon tetrachloride (CCl{sub 4}) liver injury model, this study further investigated the merit of T1{rho} relaxation for liver fibrosis evaluation. Male Sprague-Dawley rats received intraperitoneal injection of 2 ml/kg CCl{sub 4} twice weekly for up to 6 weeks. Then CCl{sub 4} was withdrawn and the animals were allowed to recover. Liver T1{rho} MRI and conventional T2-weighted images were acquired. Animals underwent MRI at baseline and at 2 days, 2 weeks, 4 weeks and 6 weeks post CCl{sub 4} injection, and they were also examined at 1 week and 4 weeks post CCl{sub 4} withdrawal. Liver histology was also sampled at these time points. Liver T1{rho} values increased slightly, though significantly, on day 2, and then increased further and were highest at week 6 post CCl{sub 4} insults. The relative liver signal intensity change on T2-weighted images followed a different time course compared with that of T1{rho}. Liver T1{rho} values decreased upon the withdrawal of the CCl{sub 4} insult. Histology confirmed the animals had typical CCl{sub 4} liver injury and fibrosis progression and regression processes. MR T1{rho} imaging can monitor CCl{sub 4}-induced liver injury and fibrosis. (orig.)

  18. Towards the gravity/CYBE correspondence beyond integrability -- Yang-Baxter deformations of $T^{1,1}$

    CERN Document Server

    Crichigno, P Marcos; Yoshida, Kentaroh

    2015-01-01

    Yang-Baxter sigma models, proposed by Klimcik and Delduc-Magro-Vicedo, have been recognized as a powerful framework for studying integrable deformations of two-dimensional non-linear sigma models. In this short article, as an important generalization, we review a non-integrable sigma model in the Yang-Baxter sigma model approach based on [arXiv:1406.2249]. In particular, we discuss a family of deformations of the 5D Sasaki-Einstein manifold $T^{1,1}$, instead of the standard deformations of the $5$-sphere S$^5$. For this purpose, we first describe a novel construction of $T^{1,1}$ as a supercoset, and provide a physical interpretation of this construction from viewpoint of the dual Klebanov-Witten field theory. Secondly, we consider a $3$-parameter deformation of $T^{1,1}$ by using classical $r$-matrices satisfying the classical Yang--Baxter equation (CYBE). The resulting metric and NS-NS two-form completely agree with the ones previously obtained via TsT (T-dual -- shift -- T-dual) transformations, and conta...

  19. Towards the gravity/CYBE correspondence beyond integrability — Yang-Baxter deformations of T1,1 —

    Science.gov (United States)

    Marcos Crichigno, P.; Matsumoto, Takuya; Yoshida, Kentaroh

    2016-01-01

    Yang-Baxter sigma models, proposed by Klimcik and Delduc-Magro-Vicedo, have been recognized as a powerful framework for studying integrable deformations of two dimensional non-linear sigma models. In this short article, as an important generalization, we review a non-integrable sigma model in the Yang-Baxter sigma model approach based on [arXiv:1406.2249]. In particular, we discuss a family of deformations of the 5D Sasaki-Einstein manifold T1,1, instead of the standard deformations of the 5-sphere S5. For this purpose, we first describe a novel construction of T1,1 as a supercoset, and provide a physical interpretation of this construction from viewpoint of the dual Klebanov-Witten field theory. Secondly, we consider a 3-parameter deformation of T1,1 by using classical r-matrices satisfying the classical Yang-Baxter equation (CYBE). The resulting metric and NS-NS two-form completely agree with the ones previously obtained via TsT (T-dual - shift - T-dual) transformations, and contain the Lunin-Maldacena background as a special case. Our result indicates that what we refer to as the gravity/CYBE(Classical Yang-Baxter Equation) correspondence can be extended beyond integrable cosets.

  20. Impact of T1 slope on surgical and adjacent segment degeneration after Bryan cervical disc arthroplasty.

    Science.gov (United States)

    Yang, Peng; Li, Yongqian; Li, Jia; Shen, Yong

    2017-01-01

    This retrospective study investigated an association between preoperative T1 slope and surgical and adjacent segment degeneration (SASD) after Bryan cervical disc arthroplasty (BCDA) in patients with cervical degenerative disc disease. Based on preoperative standing lateral radiographs, 90 patients were classified according to T1 slope that was higher or lower than the 50th percentile (high T1 or low T1, 28 and 62 patients, respectively). Patients were also classified as SASD or non-SASD (38 and 52 patients, respectively) determined by radiographs at final follow-up. Visual analog scale (VAS) and Neck Disability Index (NDI) scores for neck and arm pain were noted, and changes in the sagittal alignment of the cervical spine (SACS), functional spinal unit (FSU) angle, and FSU range of motion (ROM) were also noted. Univariate and multivariate logistic regression analyses were performed to determine the risk factors for SASD. The overall rate of SASD was 42.2% (38/90). The SACS, FSU angle, FSU ROM, and SASD rates of the high T1 and low T1 slope groups were significantly different at the last follow-up. The NDI and VAS scores of the high T1 slope group were significantly greater than those of the low T1 slope. The multivariate logistic regression analysis showed that high T1 slope and endplate coverage discrepancy (ie, residual space behind the prosthesis) were significant risk factors for SASD after BCDA. High T1 slope and endplate coverage discrepancy were associated with SASD after BCDA. Patients with a high preoperative T1 slope have a smaller FSU angle and more neck pain after BCDA.

  1. T(1) measurement of (31)P metabolites at rest and during steady-state dynamic exercise using a clinical nuclear magnetic resonance scanner.

    Science.gov (United States)

    Cettolo, V; Piorico, C; Francescato, M P

    2006-03-01

    This article illustrates some problems and possible solutions to determine the apparent spin-lattice relaxation time (T(1)) of the muscular (31)P metabolites at rest and during dynamic steady-state exercise using a clinical 1.5 T NMR scanner and a surface coil. T(1) was first estimated on a phosphates solution (phantom) using four different acquisition protocols, all based on the multiple-point "progressive saturation" method, and by fitting each data set with two different mathematical models. Subsequently, two of the four protocols and both models were used to estimate T(1) both at rest and during exercise on the calf muscles of 10 healthy volunteers. Experimental results obtained on the phantom showed that T(1) is greatly affected by the longest nominal explored repetition time (P<0.001) and by the mathematical model (P<0.001), ranging from 0.65+/-0.10 to 8.4+/-0.8 s. The two acquisition protocols applied on volunteers yielded significantly different T(1) (P<0.001), which were also rather different from the literature values for the same metabolites. Nevertheless, independently of the acquisition protocol and/or the fitting procedure, T(1) of all muscular phosphagens did not change statistically from rest to steady-state aerobic exercise.

  2. Geometry on the unit tangent bundle T1S2n+1%单位切丛T1S2n+1上的几何

    Institute of Scientific and Technical Information of China (English)

    杨小娟; 赵秋

    2007-01-01

    本文给出一般矢丛上Sasaki度量的局部表示,特别得到单位切丛T1S2n+1上Sasaki度量的表达式.利用Grassmann流形上的示性类定义了T1S2n+1上的calibration,证明了L2n+1是T1S2n+1上体积极小的子流形.采用切丛TS2n+1上的不同联络,证明了Hopf向量场是S2n+1上体积最小的单位向量场.

  3. PeaT1-induced systemic acquired resistance in tobacco follows salicylic acid-dependent pathway.

    Science.gov (United States)

    Zhang, Wei; Yang, Xiufen; Qiu, Dewen; Guo, Lihua; Zeng, Hongmei; Mao, Jianjun; Gao, Qiufeng

    2011-04-01

    Systemic acquired resistance (SAR) is an inducible defense mechanism which plays a central role in protecting plants from pathogen attack. A new elicitor, PeaT1 from Alternaria tenuissima, was expressed in Escherichia coil and characterized with systemic acquired resistance to tobacco mosaic virus (TMV). PeaT1-treated plants exhibited enhanced systemic resistance with a significant reduction in number and size of TMV lesions on wild tobacco leaves as compared with control. The quantitative analysis of TMV CP gene expression with real-time quantitative PCR showed there was reduction in TMV virus concentration after PeaT1 treatment. Similarly, peroxidase (POD) activity and lignin increased significantly after PeaT1 treatment. The real-time quantitative PCR revealed that PeaT1 also induced the systemic accumulation of pathogenesis-related gene, PR-1a and PR-1b which are the markers of systemic acquired resistance (SAR), NPR1 gene for salicylic acid (SA) signal transduction pathway and PAL gene for SA synthesis. The accumulation of SA and the failure in development of similar level of resistance as in wild type tobacco plants in PeaT1 treated nahG transgenic tobacco plants indicated that PeaT1-induced resistance depended on SA accumulation. The present work suggested that the molecular mechanism of PeaT1 inducing disease resistance in tobacco was likely through the systemic acquired resistance pathway mediated by salicylic acid and the NPR1 gene.

  4. T1 mapping in differentiation of diffuse myocardial disease in hypertrophic and dilative cardiomyopathy

    NARCIS (Netherlands)

    Puntmann, V.O.; Pastor, A.; Chen, Z.; Voigt, T.; Karim, R.; Rhode, K.; Razavi, R. S.; Schaeffter, T.; Nagel, E.

    2013-01-01

    T1 mapping was proposed as potentially valuable in quantitative assessment of diffuse myocardial fibrosis. We aimed to determine its role in differentiation of healthy myocardium from diffuse fibrosis in clinical setting. Conclusions: We demonstrate that nativeand post-contrast T1 values and their r

  5. Liver, meconium, haemorrhage: the value of T1-weighted images in fetal MRI

    Energy Technology Data Exchange (ETDEWEB)

    Zizka, Jan; Elias, Pavel; Belobradek, Zdenek; Klzo, Ludovit [Charles University Hospital, Department of Radiology, Hradec Kralove (Czech Republic); Hodik, Karel [Charles University Hospital, Department of Obstetrics and Gynaecology, Hradec Kralove (Czech Republic); Tintera, Jaroslav [Institute of Clinical and Experimental Medicine, MRI Unit, Prague (Czech Republic); Juttnerova, Vera [Charles University Hospital, Department of Medical Genetics, Hradec Kralove (Czech Republic)

    2006-08-15

    Ultrafast T2-weighted (T2-W) MRI sequences are currently considered a routine technique for fetal MR imaging. Limited experience exists with fetal T1-weighted (T1-W) imaging techniques. To determine MRI patterns of some fetal abdominal or haemorrhagic disorders with particular respect to the diagnostic value of T1-W images. In addition to standard T2-W single-shot sequences, T1-W single-shot and/or multislice sequences were employed in 25 MR examinations performed in 23 fetuses between 20 and 36 weeks of gestation for more detailed assessment of liver, meconium-filled digestive tract, haemorrhage, or further characterization of a fetal abdominal mass. Diagnostic value and presence of motion artefacts on T1-W images was recorded in each case. T1-W images enabled superior delineation of fetal liver and large intestine. They provided additional diagnostic information in 9 (39%) of 23 fetuses. One false-positive and one false-negative MRI diagnosis of malrotation anomaly were encountered. Use of single-shot T1-W sequences reduced the occurrence of motion artefacts in 64%. Our results suggest that the specific signal properties of methaemoglobin, meconium and liver are sufficiently important for T1-W sequences to become a routine part of fetal MRI protocols when dealing with digestive tract anomalies, diaphragmatic and abdominal wall defects, intraabdominal masses, and fetal haemorrhage. (orig.)

  6. Under which conditions does T1 difficulty affect T2 performance in the attentional blink?

    DEFF Research Database (Denmark)

    Nielsen, Simon; Petersen, Anders; Andersen, Tobias Søren

    When two visual targets (T1 & T2) are presented in rapid succession, performance of T2 suffers up to 900 ms. One theory of this attentional blink (Raymond, Shapiro, & Arnell, 1992) propose that T1 and T2 compete for limited processing resources (Chun & Potter, 1995), and predict that prolonging...

  7. Under which conditions does T1 difficulty affect T2 performance in the attentional blink?

    DEFF Research Database (Denmark)

    Nielsen, Simon; Petersen, Anders; Andersen, Tobias Søren

    ) found that increasing the contrast of T1 decreased the attentional blink but Chua (2005) found the opposite effect. In the current study, we varied the perceptual difficulty of T1 in the two-target paradigm (Duncan, Ward, & Shapiro, 1994) both by changing the contrast and by changing the exposure...

  8. Outcome of radiotherapy in T1 glottic carcinoma: A population-based study

    NARCIS (Netherlands)

    E.V. Sjögren (Elisabeth); R.G.J. Wiggenraad (Ruud); S. le Cessie (Saskia); S. Snijder (Simone); J. Pomp (Jaqueline); R.J.B. de Jong

    2009-01-01

    textabstractWe evaluated the radiation outcome and prognostic factors in a population-based study of early (T1N0M0) glottic carcinoma. Survival parameters and prognostic factors were evaluated by uni- and multivariate analysis in 316 consecutive irradiated patients with T1 glottic carcinoma in the C

  9. DCE-PWI 3D T1-measurement as function of time or flip angle

    DEFF Research Database (Denmark)

    Mikkelsen, Irene Klærke; Peters, David Alberg; Tietze, Anna

    Dynamic Contrast Enhanced Perfusion Weighted Imaging (DCE-PWI) and the preceding T1 measurement is usually performed with a FLASH sequence. For the sake of speed, the 3D T1 measurement is often performed by measuring the signal for a range of flip angles instead of as a function the inversion (or...

  10. Lunasin Attenuates Obesity-Associated Metastasis of 4T1 Breast Cancer Cell through Anti-Inflammatory Property.

    Science.gov (United States)

    Hsieh, Chia-Chien; Wang, Chih-Hsuan; Huang, Yu-Shan

    2016-12-15

    Obesity prevalence is increasing worldwide and is accompanied by low-grade inflammation with macrophage infiltration, which is linked with a poorer breast cancer prognosis. Lunasin is a natural seed peptide with chemopreventive properties and multiple bioactivities. This is the first study to explore the chemopreventive effects of lunasin in the obesity-related breast cancer condition using 4T1 breast cancer cells, 3T3-L1 adipocytes, and conditioned media. An obesity-related environment, such as leptin-treatment or adipocyte-conditioned medium (Ad-CM), promoted 4T1 cell proliferation and metastasis. Lunasin treatment inhibited metastasis of breast cancer cells, partially through modestly inhibiting production of the angiogenesis-mediator vascular endothelial growth factor (VEGF) and significantly by inhibiting secretion in the Ad-CM condition. Subsequently, two adipocytes inflammation models, 3T3-L1 adipocytes were stimulated by tumor necrosis factor (TNF)-α, and RAW 264.7 cell-conditioned medium (RAW-CM) was used to mimic the obese microenvironment. Lunasin significantly inhibited interleukin (IL)-6 and macrophage chemoattractant protein (MCP)-1 secretion by TNF-α stimulation, and MCP-1 secretion in the RAW-CM model. This study highlights that lunasin suppressed 3T3-L1 adipocyte inflammation and inhibited 4T1 breast cancer cell migration. Interestingly, lunasin exerted more effective anti-metastasis activity in the obesity-related condition models, indicating that it possesses anti-inflammatory properties and blocks adipocyte-cancer cell cross-talk.

  11. Loss of PiT-1 results in abnormal endocytosis in the yolk sac visceral endoderm.

    Science.gov (United States)

    Wallingford, Mary C; Giachelli, Cecilia M

    2014-08-01

    PiT-1 protein is a transmembrane sodium-dependent phosphate (Pi) transporter. PiT-1 knock out (KO) embryos die from largely unknown causes by embryonic day (E) 12.5. We tested the hypothesis that PiT-1 is required for endocytosis in the embryonic yolk sac (YS) visceral endoderm (VE). Here we present data supporting that PiT-1 KO results in a YS remodeling defect and decreased endocytosis in the YS VE. The remodeling defect is not due to an upstream cardiomyocyte requirement for PiT-1, as SM22αCre-specific KO of PiT-1 in the developing heart and the YS mesodermal layer (ME) does not recapitulate the PiT-1 global KO phenotype. Furthermore, we find that high levels of PiT-1 protein localize to the YS VE apical membrane. Together these data support that PiT-1 is likely required in YS VE. During normal development maternal immunoglobulin (IgG) is endocytosed into YS VE and accumulates in the apical side of the VE in a specialized lysosome termed the apical vacuole (AV). We have identified a reduction in PiT-1 KO VE cell height and a striking loss of IgG accumulation in the PiT-1 KO VE. The endocytosis genes Tfeb, Lamtor2 and Snx2 are increased at the RNA level. Lysotracker Red staining reveals a loss of distinct AVs, and yolk sacs incubated ex vivo with phRODO Green Dextran for Endocytosis demonstrate a functional loss of endocytosis. As yolk sac endocytosis is controlled in part by microautophagy, but expression of LC3 had not been examined, we investigated LC3 expression during yolk sac development and found stage-specific LC3 RNA expression that is predominantly from the YS VE layer at E9.5. Normalized LC3-II protein levels are decreased in the PiT-1 KO YS, supporting a requirement for PiT-1 in autophagy in the YS. Therefore, we propose the novel idea that PiT-1 is central to the regulation of endocytosis and autophagy in the YS VE.

  12. Differential Regulation of ERK1/2 and mTORC1 Through T1R1/T1R3 in MIN6 Cells

    OpenAIRE

    Wauson, Eric M.; Guerra, Marcy L.; Dyachok, Julia; McGlynn, Kathleen; Giles, Jennifer; Ross, Elliott M.; Cobb, Melanie H.

    2015-01-01

    The MAPKs ERK1/2 respond to nutrients and other insulin secretagogues in pancreatic β-cells and mediate nutrient-dependent insulin gene transcription. Nutrients also stimulate the mechanistic target of rapamycin complex 1 (mTORC1) to regulate protein synthesis. We showed previously that activation of both ERK1/2 and mTORC1 in the MIN6 pancreatic β-cell-derived line by extracellular amino acids (AAs) is at least in part mediated by the heterodimeric T1R1/T1R3, a G protein-coupled receptor. We ...

  13. Minireview: 3-Iodothyronamine (T1AM): a new player on the thyroid endocrine team?

    Science.gov (United States)

    Scanlan, Thomas S

    2009-03-01

    3-Iodothyronamine (T(1)AM) is an endogenous compound with chemical features that are similar to thyroid hormone. T(1)AM has a carbon skeleton identical to that of T(4) and contains a single carbon-iodine bond. Theoretically, T(1)AM could be produced from T(4) by enzymatic decarboxylation and deiodination. Recent studies show that T(1)AM and higher iodinated thyronamines are subject to similar metabolic processing as iodothyronines such as T(4), suggesting a biological linkage between iodothyronines and iodothyronamines. In addition, single doses of T(1)AM administered to rodents induce a hypometabolic state that in certain ways resembles hibernation and is opposite to the effects of excess T(4). This review will discuss the latest developments on this recently discovered thyroid hormone derivative.

  14. Robust T1-weighted structural brain imaging and morphometry at 7T using MP2RAGE.

    Directory of Open Access Journals (Sweden)

    Kieran R O'Brien

    Full Text Available PURPOSE: To suppress the noise, by sacrificing some of the signal homogeneity for numerical stability, in uniform T1 weighted (T1w images obtained with the magnetization prepared 2 rapid gradient echoes sequence (MP2RAGE and to compare the clinical utility of these robust T1w images against the uniform T1w images. MATERIALS AND METHODS: 8 healthy subjects (29.0 ± 4.1 years; 6 Male, who provided written consent, underwent two scan sessions within a 24 hour period on a 7T head-only scanner. The uniform and robust T1w image volumes were calculated inline on the scanner. Two experienced radiologists qualitatively rated the images for: general image quality; 7T specific artefacts; and, local structure definition. Voxel-based and volume-based morphometry packages were used to compare the segmentation quality between the uniform and robust images. Statistical differences were evaluated by using a positive sided Wilcoxon rank test. RESULTS: The robust image suppresses background noise inside and outside the skull. The inhomogeneity introduced was ranked as mild. The robust image was significantly ranked higher than the uniform image for both observers (observer 1/2, p-value = 0.0006/0.0004. In particular, an improved delineation of the pituitary gland, cerebellar lobes was observed in the robust versus uniform T1w image. The reproducibility of the segmentation results between repeat scans improved (p-value = 0.0004 from an average volumetric difference across structures of ≈ 6.6% to ≈ 2.4% for the uniform image and robust T1w image respectively. CONCLUSIONS: The robust T1w image enables MP2RAGE to produce, clinically familiar T1w images, in addition to T1 maps, which can be readily used in uniform morphometry packages.

  15. COMPUTED TOMOGRAPHY MORPHOMETRIC ANALYSIS OF THE VERTEBRAE C7 AND T1

    Directory of Open Access Journals (Sweden)

    FLÁVIO GERARDO BENITES ZELADA

    Full Text Available ABSTRACT Objective: The anatomical study of the vertebrae C7 and T1 of the cervicothoracic junction aimed to evaluate quantitatively, by axial computerized tomography (CT, the linear and angular dimensions of the anatomical laminae of the vertebrae of the cervicothoracic junction C7 and T1 in adults over 18 years. Methods: We retrospectively analyzed 49 CT of the cervical and thoracic spine (C7 and T1 of individuals over 18 years, of both sexes. We also evaluated the length and thickness of the laminae, as well as spinolaminar angle in axial sections of C7 and T1 at the point of least thickness between the inner cortical layers. The variables were correlated with age groups and sex of the individuals. Statistical analysis was performed using the t test and the results were considered significant when p<0.05. Results: After analyzing tomographic measurements of 49 patients, it was found that men had greater laminae thickness than women, both in C7 and T1, with 71% of C7 laminae and 92% of T1 laminae thicker than 5mm, and 97% of C7 laminae and 100% of T1 thicker than 4mm. The mean spinolaminar angle was 56.40 degrees in C7 and 57.31 degrees in T1. Conclusion: This study brings important anatomical information about the cervicothoracic junction C7 and T1 in the Brazilian population, showing that fixation of C7 and T1 with intralaminar screws is anatomically possible.

  16. In vivo measurement of a new source of contrast, the dipolar relaxation time, T1D , using a modified inhomogeneous magnetization transfer (ihMT) sequence.

    Science.gov (United States)

    Varma, Gopal; Girard, Olivier M; Prevost, Valentin H; Grant, Aaron K; Duhamel, Guillaume; Alsop, David C

    2017-10-01

    This paper describes a technique that can be used in vivo to measure the dipolar relaxation time, T1D , of macromolecular protons contributing to magnetization transfer (MT) in tissues and to produce quantitative T1D maps. The technique builds upon the inhomogeneous MT (ihMT) technique that is particularly sensitive to tissue components with long T1D . A standard ihMT experiment was altered to introduce a variable time for switching between positive and negative offset frequencies for RF saturation. A model for the dependence of ihMT was developed and used to fit data acquired in vivo. Application of the method to images from brains of healthy volunteers produced values of T1D  = (5.9 ± 1.2) ms in gray matter and T1D  = (6.2 ± 0.4) ms in white matter regions and provided maps of the T1D parameter. The model and experiments described provide access to a new relaxation characteristic of tissue with potentially unique diagnostic information. Magn Reson Med 78:1362-1372, 2017. © 2016 International Society for Magnetic Resonance in Medicine. © 2016 International Society for Magnetic Resonance in Medicine.

  17. T1- Thresholds in Black Holes Increase Clinical-Radiological Correlation in Multiple Sclerosis Patients.

    Directory of Open Access Journals (Sweden)

    Christian Thaler

    Full Text Available Magnetic Resonance Imaging (MRI is an established tool in diagnosing and evaluating disease activity in Multiple Sclerosis (MS. While clinical-radiological correlations are limited in general, hypointense T1 lesions (also known as Black Holes (BH have shown some promising results. The definition of BHs is very heterogeneous and depends on subjective visual evaluation.We aimed to improve clinical-radiological correlations by defining BHs using T1 relaxation time (T1-RT thresholds to achieve best possible correlation between BH lesion volume and clinical disability.40 patients with mainly relapsing-remitting MS underwent MRI including 3-dimensional fluid attenuated inversion recovery (FLAIR, magnetization-prepared rapid gradient echo (MPRAGE before and after Gadolinium (GD injection and double inversion-contrast magnetization-prepared rapid gradient echo (MP2RAGE sequences. BHs (BHvis were marked by two raters on native T1-weighted (T1w-MPRAGE, contrast-enhancing lesions (CE lesions on T1w-MPRAGE after GD and FLAIR lesions (total-FLAIR lesions were detected separately. BHvis and total-FLAIR lesion maps were registered to MP2RAGE images, and the mean T1-RT were calculated for all lesion ROIs. Mean T1 values of the cortex (CTX were calculated for each patient. Subsequently, Spearman rank correlations between clinical scores (Expanded Disability Status Scale and Multiple Sclerosis Functional Composite and lesion volume were determined for different T1-RT thresholds.Significant differences in T1-RT were obtained between all different lesion types with highest T1 values in visually marked BHs (BHvis: 1453.3±213.4 ms, total-FLAIR lesions: 1394.33±187.38 ms, CTX: 1305.6±35.8 ms; p1500 ms (Expanded Disability Status Scale vs. lesion volume: rBHvis = 0.442 and rtotal-FLAIR = 0.497, p<0.05; Multiple Sclerosis Functional Composite vs. lesion volume: rBHvis = -0.53 and rtotal-FLAIR = -0.627, p<0.05.Clinical-radiological correlations in MS patients are

  18. T1- Thresholds in Black Holes Increase Clinical-Radiological Correlation in Multiple Sclerosis Patients.

    Science.gov (United States)

    Thaler, Christian; Faizy, Tobias; Sedlacik, Jan; Holst, Brigitte; Stellmann, Jan-Patrick; Young, Kim Lea; Heesen, Christoph; Fiehler, Jens; Siemonsen, Susanne

    2015-01-01

    Magnetic Resonance Imaging (MRI) is an established tool in diagnosing and evaluating disease activity in Multiple Sclerosis (MS). While clinical-radiological correlations are limited in general, hypointense T1 lesions (also known as Black Holes (BH)) have shown some promising results. The definition of BHs is very heterogeneous and depends on subjective visual evaluation. We aimed to improve clinical-radiological correlations by defining BHs using T1 relaxation time (T1-RT) thresholds to achieve best possible correlation between BH lesion volume and clinical disability. 40 patients with mainly relapsing-remitting MS underwent MRI including 3-dimensional fluid attenuated inversion recovery (FLAIR), magnetization-prepared rapid gradient echo (MPRAGE) before and after Gadolinium (GD) injection and double inversion-contrast magnetization-prepared rapid gradient echo (MP2RAGE) sequences. BHs (BHvis) were marked by two raters on native T1-weighted (T1w)-MPRAGE, contrast-enhancing lesions (CE lesions) on T1w-MPRAGE after GD and FLAIR lesions (total-FLAIR lesions) were detected separately. BHvis and total-FLAIR lesion maps were registered to MP2RAGE images, and the mean T1-RT were calculated for all lesion ROIs. Mean T1 values of the cortex (CTX) were calculated for each patient. Subsequently, Spearman rank correlations between clinical scores (Expanded Disability Status Scale and Multiple Sclerosis Functional Composite) and lesion volume were determined for different T1-RT thresholds. Significant differences in T1-RT were obtained between all different lesion types with highest T1 values in visually marked BHs (BHvis: 1453.3±213.4 ms, total-FLAIR lesions: 1394.33±187.38 ms, CTX: 1305.6±35.8 ms; p1500 ms (Expanded Disability Status Scale vs. lesion volume: rBHvis = 0.442 and rtotal-FLAIR = 0.497, p<0.05; Multiple Sclerosis Functional Composite vs. lesion volume: rBHvis = -0.53 and rtotal-FLAIR = -0.627, p<0.05). Clinical-radiological correlations in MS patients are

  19. 稳定表达甜味受体蛋白T1R2/T1R3的HEK293细胞系的建立%Establishment of HEK293 Cell Line Stably Expressing Sweet Preceptor Protein T1R2/T1R3

    Institute of Scientific and Technical Information of China (English)

    钱玲玲; 秦玉梅; 邓少平

    2013-01-01

    以小鼠舌组织为对象,提取总mRNA,并以此为模板,使用自行设计的引物通过RT-PCR扩增Gα15、T1R2和T1R3目的片段.构建重组质粒pEGFP-C1-Gα 15、pDsRed1-N1-T1R2、pcDNATM6.2/N-YFP-DEST-T1R3.以脂质体介导的方法转染HEK293细胞,经抗性筛选后,通过极限稀释法获得稳定表达T1R2/T1R3的HEK293细胞系,最后通过RT-PCR,荧光显微镜及Western blot方法在基因及蛋白质水平上对建立的稳定表达细胞系进行鉴定.基因及蛋白质水平上的结果均表明,目的基因Gα15、T1R2/T1R3成功导入HEK293细胞中,并且稳定表达.该细胞系的建立为细胞水平上甜味机理的体外研究(如甜味识别热动力学等)提供了稳定的细胞来源.%It is to establish HEK293 cell line which could stably express sweet taste receptor protein T1R2/T1R3. Firstly,extract total mRNA from mouse tongue tissue,then amplify Gal5,TlR2 and T1R3 target gene fragment by RT-PCR with self-designed primers and above total mRNA template. Then,establish the recombinant plasmid pEGFP -C1 -Gα15,pDsRedl -N1 -T1R2, pcDNA TM6.2/N-YFP-DEST-TlR3 and introduce them into the HEK293 cells by liposome. After resistance screening,the HEK293 cell line with the ability of stable expressing T1R2/T1R3 was obtained in a limit dilution method. Finally,the stable cell line with sweet receptor protein T1R2/ T1R3 was identified by RT-PCR,fluorescence microscopy and Western blot. The results in gene and protein level show that Gαl5、T1R2/T1R3 are successfully introduced into HEK293 cell line and are stably expressed. The establishment of HEK293 cell line provides a stable cell source for the study of sweetness mechanism in vitro (such as sweet recognition thermodynamics,etc.) at cell level.

  20. Brain abnormalities in bipolar disorder detected by quantitative T1ρ mapping.

    Science.gov (United States)

    Johnson, C P; Follmer, R L; Oguz, I; Warren, L A; Christensen, G E; Fiedorowicz, J G; Magnotta, V A; Wemmie, J A

    2015-02-01

    Abnormal metabolism has been reported in bipolar disorder, however, these studies have been limited to specific regions of the brain. To investigate whole-brain changes potentially associated with these processes, we applied a magnetic resonance imaging technique novel to psychiatric research, quantitative mapping of T1 relaxation in the rotating frame (T1ρ). This method is sensitive to proton chemical exchange, which is affected by pH, metabolite concentrations and cellular density with high spatial resolution relative to alternative techniques such as magnetic resonance spectroscopy and positron emission tomography. Study participants included 15 patients with bipolar I disorder in the euthymic state and 25 normal controls balanced for age and gender. T1ρ maps were generated and compared between the bipolar and control groups using voxel-wise and regional analyses. T1ρ values were found to be elevated in the cerebral white matter and cerebellum in the bipolar group. However, volumes of these areas were normal as measured by high-resolution T1- and T2-weighted magnetic resonance imaging. Interestingly, the cerebellar T1ρ abnormalities were normalized in participants receiving lithium treatment. These findings are consistent with metabolic or microstructural abnormalities in bipolar disorder and draw attention to roles of the cerebral white matter and cerebellum. This study highlights the potential utility of high-resolution T1ρ mapping in psychiatric research.

  1. T-1, a mitotic arrester, alters centrosome configurations in fertilized sea urchin eggs.

    Science.gov (United States)

    Itoh, T J; Schatten, H; Schatten, G; Mazia, D; Kobayashi, A; Sato, H

    1990-01-01

    T-1 induces modifications in the shape of the centrosome at division in fertilized eggs of the North American sea urchin, Lytechinus pictus. Phase contrast microscopy observations of mitotic apparatus isolated from T-1-treated (1.7-8.5 microM) eggs at first division shows that the centrosomes already begin to spread or to separate by prophase and that the mitotic spindle is barrel-shaped. When eggs are fertilized with sperm that have been preteated with T-1, the centrosomes become flattened; the spindles are of normal length. Immunofluorescence microscopy using an anti-centrosomal monoclonal antibody reveals that T-1 modifies the structure of the centrosome so that barrel-shaped spindles with broad centrosomes are observed at metaphase, rather than the expected focused poles and fusiform spindle. Higher concentrations of T-1 induce fragmentation of centrosomes, causing abnormal accumulation of microtubules in polar regions. These results indicate that T-1 directly alters centrosomal configuration from a compact structure to a flattened or a spread structure. T-1 can be classified as a new category of mitotic drugs that may prove valuable in dissecting the molecular nature of centrosomes.

  2. Lumbosacral lipoma : gadolinium-enhanced fat saturation T1 weighted MR image is necessary?

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Man Won; Kim, Hyun Chul; Chung, Tae Woong; Seo, Jeong Jin; Chung, Gwang Woo; Kim, Yun Hyeon; Kim, Jae Kyu; Park, Jin Gyoon; Kang, Heoung Keun [Chonnam Univ. Medical School and Chonnam Univ. Institute of Medical Science, Kwangju (Korea, Republic of)

    1999-04-01

    To evaluate the usefulness of contrast-enhanced fat saturation T1-weighted imaging for the evaluation of spinal lipoma, compared with clinical symptoms and surgical findings. Ten patients with lipomyelomeningocele, confirmed by surgery, were included in this study. In all cases, conventional spin echo T1-and T2-weighted MR imaging, and contrast-enhanced fat saturation T1-weighted imaging was performed to evaluate clinical symptoms, the position of the conus medullaris, the presence of cord tethering, and associated anomalies, and to compare the relative usefulness of the techniques. All ten patients were suffering from lipomyelomeningocele without filum terminale fibrolipoma or intradural lipoma. All cases were associated with cord tethering. As associated anomalies, there were seven cases of syringomyelia without hydrocephalus or anorectal anomaly. To evaluate the position of the spinal conus and the presence of cord tethering, conventional T1-weighted imaging was more useful than the contrast-enhanced fat saturation equivalent. In patients with early-stage spinal lipoma, MRI is useful for evaluation of the causes and position of cord tethering and associated anomalies Our results suggest that contrast-enhanced fat saturation T1-weighted images do not provide additional information concerning spinal lipoma, and that for the diagnosis of this condition, conventional T1 and T2-weighted images are more useful than those obtained by contrast-enhanced fat saturation T1-weighted imaging.

  3. Native Myocardial T1 as a Biomarker of Cardiac Structure in Non-Ischemic Cardiomyopathy.

    Science.gov (United States)

    Shah, Ravi V; Kato, Shingo; Roujol, Sebastien; Murthy, Venkatesh; Bellm, Steven; Kashem, Abyaad; Basha, Tamer; Jang, Jihye; Eisman, Aaron S; Manning, Warren J; Nezafat, Reza

    2016-01-15

    Diffuse myocardial fibrosis is involved in the pathology of nonischemic cardiomyopathy (NIC). Recently, the application of native (noncontrast) myocardial T1 measurement has been proposed as a method for characterizing diffuse interstitial fibrosis. To determine the association of native T1 with myocardial structure and function, we prospectively studied 39 patients with NIC (defined as left ventricular ejection fraction (LVEF) ≤ 50% without cardiac magnetic resonance (CMR) evidence of previous infarction) and 27 subjects with normal LVEF without known overt cardiovascular disease. T1, T2, and extracellular volume fraction (ECV) were determined over 16 segments across the base, mid, and apical left ventricular (LV). NIC participants (57 ± 15 years) were predominantly men (74%), with a mean LVEF 34 ± 10%. Subjects with NIC had a greater native T1 (1,131 ± 51 vs 1,069 ± 29 ms; p NIC was associated with a greater LVEF (β = -0.59, p = 0.0003), greater right ventricular ejection fraction (β = -0.47, p = 0.006), and smaller left atrial volume index (β = 0.51, p = 0.001). The regional distribution of native myocardial T1 was similar in patients with and without NIC. In NIC, native myocardial T1 is elevated in all myocardial segments, suggesting a global (not regional) abnormality of myocardial tissue composition. In conclusion, native T1 may represent a rapid, noncontrast alternative to ECV for delineating myocardial tissue remodeling in NIC.

  4. Limited redundancy in genes regulated by Cyclin T2 and Cyclin T1

    Directory of Open Access Journals (Sweden)

    Yu Wendong

    2011-07-01

    Full Text Available Abstract Background The elongation phase, like other steps of transcription by RNA Polymerase II, is subject to regulation. The positive transcription elongation factor b (P-TEFb complex allows for the transition of mRNA synthesis to the productive elongation phase. P-TEFb contains Cdk9 (Cyclin-dependent kinase 9 as its catalytic subunit and is regulated by its Cyclin partners, Cyclin T1 and Cyclin T2. The HIV-1 Tat transactivator protein enhances viral gene expression by exclusively recruiting the Cdk9-Cyclin T1 P-TEFb complex to a RNA element in nascent viral transcripts called TAR. The expression patterns of Cyclin T1 and Cyclin T2 in primary monocytes and CD4+ T cells suggests that Cyclin T2 may be generally involved in expression of constitutively expressed genes in quiescent cells, while Cyclin T1 may be involved in expression of genes up-regulated during macrophage differentiation, T cell activation, and conditions of increased metabolic activity To investigate this issue, we wished to identify the sets of genes whose levels are regulated by either Cyclin T2 or Cyclin T1. Findings We used shRNA lentiviral vectors to stably deplete either Cyclin T2 or Cyclin T1 in HeLa cells. Total RNA extracted from these cells was subjected to cDNA microarray analysis. We found that 292 genes were down- regulated by depletion of Cyclin T2 and 631 genes were down-regulated by depletion of Cyclin T1 compared to cells transduced with a control lentivirus. Expression of 100 genes was commonly reduced in either knockdown. Additionally, 111 and 287 genes were up-regulated when either Cyclin T2 or Cyclin T1 was depleted, respectively, with 45 genes in common. Conclusions These results suggest that there is limited redundancy in genes regulated by Cyclin T1 or Cyclin T2.

  5. Native Magnetic Resonance T1-Mapping Identifies Diffuse Myocardial Injury in Hypothyroidism.

    Directory of Open Access Journals (Sweden)

    Xia Gao

    Full Text Available Hypothyroidism (HT is characterized by thyroid hormone deficiencies, which can lead to diffuse myocardial interstitium lesions in patients with HT. Myocardial longitudinal relaxation time (T1 mapping is a potential diagnostic tool for quantifying diffuse myocardial injury. This study aimed to assess the usefulness of T1 mapping in identifying myocardial involvement in HT, and determine the relationship between T1 values and myocardial function.A cross-sectional study was conducted with 30 untreated HT patients alongside 23 age- and sex-matched healthy controls. All subjects underwent cardiac magnetic resonance (CMR with non-contrast (native T1 mapping using a modified Look-Locker inversion-recovery (MOLLI sequence to assess the native T1 values of myocardium and cardiac function.Native myocardial T1 values were significantly increased in HT patients, especially those with pericardial effusion (p < 0.05, compared with healthy controls. In addition, significantly reduced peak filling rate (PFR and prolonged peak filling time (PFT were obtained (p < 0.05 in HT patients compared with controls. Furthermore, stroke volume (SV and cardiac index (CI were significantly lower in HT patients than controls (all p < 0.05. Interestingly, native T1 values were negatively correlated with free triiodothyronine (FT3, PFR, SV and CI (all p < 0.05.Diffuse myocardial injuries are common in HT patients, and increased T1 values are correlated with FT3 and cardiac function impairment. These findings indicate that T1 mapping might be useful in evaluating myocardial injuries in HT patients.

  6. Excellent waste biomass-degrading performance of Trichoderma asperellum T-1 during submerged fermentation.

    Science.gov (United States)

    Wang, Qun; Chen, Liang; Yu, Daobing; Lin, Hui; Shen, Qi; Zhao, Yuhua

    2017-12-31

    The random disposal and incineration of agricultural residues cause resources waste and environmental pollution. The potential of waste biomass for the production of alternative liquid fuels is increasing and the bioconversion of lignocellulose to fermentable monomeric sugars is essential for second-generation biofuel production. Here, natural and pretreated switch grass or rice straw were fermented by both Trichoderma asperellum T-1 and Trichoderma reesei QM6a, with the fermentation results highlighted the potential of T. asperellum T-1 in the degradation of natural waste lignocellulosic materials. In fermenting different substrates, the filter paper activity, β-glucosidase activity, xylanase activity and carboxymethyl cellulase activity of T-1 can respectively reach 1.88, 8.00, 7.15 and 20.52 times that of QM6a. Although acid pretreatment could improve the enzyme activities of both T-1 and QM6a, its effect on T-1 was much smaller than that on QM6a. Moreover, strain T-1 fermented the natural rice straw better than the pretreated rice straw. Therefore, T-1 is considered to be more suitable for the degradation of natural biomass, especially for the degradation of rice straw. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and scanning electron microscopy (SEM) showed that the cellulase series secreted by T. asperellum T-1 was more abundant, and its substrate deconstruction ability was stronger than T. reesei QM6a. All these results suggest the potential of T. asperellum T-1 in the degradation of natural waste lignocellulosic material, with practical benefits in terms of cost and pollution reduction. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Modulation of Sweet Taste by Umami Compounds via Sweet Taste Receptor Subunit hT1R2: e0124030

    National Research Council Canada - National Science Library

    Jaewon Shim; Hee Jin Son; Yiseul Kim; Ki Hwa Kim; Jung Tae Kim; Hana Moon; Min Jung Kim; Takumi Misaka; Mee-Ra Rhyu

    2015-01-01

    ...), in human sweet taste receptor hT1R2/hT1R3-expressing cells. The sensitivity of sucrose to hT1R2/hT1R3 was significantly attenuated by MSG and umami active peptides but not by umami active nucleotides...

  8. Toric data and Killing forms on homogeneous Sasaki-Einstein manifold $T^{1,1}$

    CERN Document Server

    Slesar, Vladimir; Vilcu, Gabriel Eduard

    2015-01-01

    Throughout this paper we investigate the complex structure of the conifold $C(T^{1,1})$ basically making use of the interplay between symplectic and complex approaches of the K\\"{a}hler toric manifolds. The description of the Calabi-Yau manifold $C(T^{1,1})$ using toric data allows us to write explicitly the complex coordinates and apply standard methods for extracting special Killing forms on the base manifold. As an outcome, we obtain the complete set of special Killing forms on the five-dimensional Sasaki-Einstein space $T^{1,1}$.

  9. Thalidomide promotes leukocytosis in mice inoculated with 4T1 mammary carcinoma

    Directory of Open Access Journals (Sweden)

    Diego Carlos dos Reis

    2014-02-01

    Full Text Available The aim of this study was to evaluate the therapy effect of thalidomide in the 4T1 murine mammary carcinoma. 4T1 cell suspension was injected into the posterior left flank of all animals to obtain solid tumors. Five days after inoculation, the treatment group was orally administered 150 mg/kg of thalidomide for seven days. Tumors were measured every 48 hours until the end of treatment. Whole blood was collected for hematology analysis. Our results suggest that thalidomide therapy increase the number of circulating leukocytes in the 4T1 murine mammary carcinoma, and this response is accompanied by a decrease in tumor growth.

  10. The Study of Fast T1 Mapping of Human Brain%大脑快速T1图谱成像研究

    Institute of Scientific and Technical Information of China (English)

    江克; 钟耀祖; 吴垠; 朱燕杰

    2016-01-01

    大脑快速 T1图谱成像是一种量化磁共振成像技术,可以为帕金森、癫痫、肝脑病等脑部疾病的诊断提供重要参考依据。现有的大脑快速 T1图谱成像技术可以将成像速度提高到几秒/层,然而主磁场、发射场的不均性(尤其在高场下)以及大脑内部结构的磁化率差异,降低了成像精确性,限制了其在临床上的推广应用。针对上述缺点,文章提出一种基于 TurboFLASH技术的大脑快速 T1图谱成像方法,并先后在计算机仿真实验、仿体以及人体试验中进行验证。实验结果表明,文章提出的方法测得的大脑组织 T1值与金标准及文献中报导的值非常接近(误差<3%),同时扫描速度提高到3秒/层,空间分辨率为1.1 mm×1.1 mm×4 mm,2分钟内即可完成全脑采集。%Fast brain T1 mapping is a quantitative technique of magnetic resonance imaging, and can provide important reference for the diagnosis of several brain diseases, such as Parkinson, epilepsy and hepatic encephalopathy. Fast T1 mapping techniques proposed previously had sped up acquisition to several seconds per slice. However, most of these techniques suffered seriously from the ifeld inhomogeneity of main ifeld, transmit ifeld and susceptibility artifacts, which decreased the imaging accuracy and limited the clinic applications. To overcome the above mentioned shortcomings, we proposed a fast brain T1 mapping technique based on TurboFLASH and evaluated it on computer simulation, phantom experiment, and human brain T1 mapping. Results showed that T1 values from the proposed method were very close to the gold standard and literature (differences being less than 3%). Besides, the proposed technique can increase the acquisition speed to 3s per slice (with a slice resolution of 1.1 mm×1.1 mm) and 2 min for the whole brain (with a 4 mm slice distance).

  11. Hormonal regulation of dipeptide transporter (PepT1) in Caco-2 cells with normal and anoxia/reoxygenation management

    Institute of Scientific and Technical Information of China (English)

    Bing-Wei Sun; Xiao-Chen Zhao; Guang-Ji Wang; Ning Li; Jie-Shou Li

    2003-01-01

    AIM: To determine the regulation effects of recombinant human growth hormone (rhGH) on dipeptide transporter (PepT1) in Caco-2 cells with normal culture and anoxia/reoxygenation injury.METHODS: A human intestinal cell monolayer (Caco-2) was used as the in vitro model of human small intestine and cephalexin as the model substrate for dipeptide transporter (PepT1). Caco-2 cells grown on Transwell membrane filters were preincubated in the presence of rhGH in the culture medium for 4 d, serum was withdrawn from monolayers for 24 h before each experiment. The transport experiments of cephalexin across apical membromes were then conducted;Caco-2 cells grown on multiple well dishes (24 pore) with normal culture or anoxia/reoxygenation injury were preincubated with rhGH as above and uptake of cephalexin was then measured.RESULTS: The transport and uptake of cephelaxin across apical membranes of Caco-2 cells after preincubation with rhGH were significantly increased compared with controls (P=0.045, 0.0223). Also, addition of rhGH at physiological concentration (34 nM) to incubation medium greatly stimulates cephalexin uptake by anoxia/reoxygenation injuried Caco-2 cells (P=0.0116), while the biological functions of PepT1 in injured Caco-2 cells without rhGH were markedly downregulated. Northem blot analysis showed that the level of PepT1 mRNA of rhGH-treated injured Caco-2cells was greatly increased compared to controls.CONCLUSION: The present results of rhGH stimulating the uptake and transport of cephalexin indicated that rhGH greatly upregulates the physiological effects of dipeptide transporters of Caco-2 cells. The alteration in the gene expression may be a mechanism of regulation of PepT1. In addition, Caco-2 cells take up cephalexin by the Proton-dependent dipeptide transporters that closely resembles the transporters present in the intestine. Caco-2 cells represent an ideal cellular model for future studies of the dipeptide transporter.

  12. A Genetic Switch to Hypervirulence Reduces Colonization Phenotypes of the Globally Disseminated Group A Streptococcus M1T1 Clone

    Science.gov (United States)

    Hollands, Andrew; Pence, Morgan A.; Timmer, Anjuli M.; Osvath, Sarah R.; Turnbull, Lynne; Whitchurch, Cynthia B.; Walker, Mark J.; Nizet, Victor

    2010-01-01

    Background The recent resurgence of invasive group A streptococcal disease has been paralleled by the emergence of the M1T1 clone. Recently, invasive disease initiation to has been linked to mutations in the covR/S two-compnent regulator. Here we investigate if a fitness cost is associated with covS mutation that counterbalances hypervirulence. Methods Wild-type M1T1 GAS and an isogenic covS mutant derived from animal passage were compared for adherence to human laryngeal epithelial cells, keratinocytes or fibronectin, biofilm formation, and binding to intact mouse skin. Targeted mutagenesis of capsule expression from both strains was performed for analysis of its unique contribution to the observed phenotypes. Results The covS mutant bacteria showed reduced capacity to bind to epithelial cell layers as a consequence of increased capsule expression. The covS mutant strain also had reduced capacity to bind fibronectin and to form biofilms on plastic and epithelial cell layers. A defect in skin adherence of the covS mutant strain was demonstrated in a murine model. Conclusions Reduced colonization capacity provides a potential explanation as to why the covS mutation conferring hypervirulence has not become fixed in the globally-disseminated M1T1 GAS clone, but rather may arise anew under innate immune selection in individual patients. PMID:20507231

  13. Genetic switch to hypervirulence reduces colonization phenotypes of the globally disseminated group A streptococcus M1T1 clone.

    Science.gov (United States)

    Hollands, Andrew; Pence, Morgan A; Timmer, Anjuli M; Osvath, Sarah R; Turnbull, Lynne; Whitchurch, Cynthia B; Walker, Mark J; Nizet, Victor

    2010-07-01

    The recent resurgence of invasive group A streptococcal disease has been paralleled by the emergence of the M1T1 clone. Recently, invasive disease initiation has been linked to mutations in the covR/S 2-component regulator. We investigated whether a fitness cost is associated with the covS mutation that counterbalances hypervirulence. Wild-type M1T1 group A Streptococcus and an isogenic covS-mutant strain derived from animal passage were compared for adherence to human laryngeal epithelial cells, human keratinocytes, or fibronectin; biofilm formation; and binding to intact mouse skin. Targeted mutagenesis of capsule expression of both strains was performed for analysis of its unique contribution to the observed phenotypes. The covS-mutant bacteria showed reduced capacity to bind to epithelial cell layers as a consequence of increased capsule expression. The covS-mutant strain also had reduced capacity to bind fibronectin and to form biofilms on plastic and epithelial cell layers. A defect in skin adherence of the covS-mutant strain was demonstrated in a murine model. Reduced colonization capacity provides a potential explanation for why the covS mutation, which confers hypervirulence, has not become fixed in the globally disseminated M1T1 group A Streptococcus clone, but rather may arise anew under innate immune selection in individual patients.

  14. A novel protein with anti-metastasis activity on 4T1 carcinoma from medicinal fungus Cordyceps militaris.

    Science.gov (United States)

    Yang, Qing; Yin, Yalin; Yu, Guojun; Jin, Yanxia; Ye, Xiangdong; Shrestha, Alok; Liu, Wei; Yu, Wenhui; Sun, Hui

    2015-09-01

    Cordyceps militaris is a famous fungus used in traditional Chinese medicine for nearly one thousand years. And its fruiting body is known to possess anticancer and immunomodulatory activities. This study describes the isolation, characterization, and test of antitumor activity of a C. militaris protein, called here as "C. militaris immunoregulatory protein" (CMIP). CMIP was purified through a three-step chromatographic procedure. The MS analyses showed that CMIP corresponded to an uncharacterized protein (CCM_01955) in the C. militaris transcriptional database. Circular dichroism of CMIP revealed the composition of 35.5% β-sheet, 18.5% α-helix, 17.0% turn and 29.0% random coil. No significant cytotoxicity of CMIP was observed on HeLa, HepG2 and 4T1 tumor cells. However, CMIP demonstrated anti-metastasis activity on a mouse model of 4T1 breast cancer lung metastasis. It reduced the number of tumor nodules in the lung of tumor-bearing mice and prolonged their survival time. Furthermore, proliferation of the 4T1 cells was inhibited by macrophage-CMIP conditioned media. And the mRNA levels of cytokines TNF-α, IL-1β and IL-6 were increased significantly in peritoneal macrophages treated by CMIP. These results reveal the antitumor potential of CMIP, thus reinforcing the importance of biochemical prospecting of C. militaris.

  15. Regulation of cell proliferation and cell density by the inorganic phosphate transporter PiT1

    Directory of Open Access Journals (Sweden)

    Byskov Kristina

    2012-03-01

    Full Text Available Abstact Background The inorganic phosphate (Pi transporter, PiT1 (SLC20A1, is ubiquitously expressed in mammalian cells. It has previously been shown that down-regulation of PiT1 severely impaired the proliferation of two transformed human cells lines, HepG2 and HeLa, and the tumorigenicity of HeLa cells in nude mice. Moreover, PiT1 knock-out mice do not survive past E12.5 and from E10.5, the embryos were found to be growth-retarded and showed reduced proliferation of liver cells. Isolated mouse embryonic fibroblasts with knocked out as well as reduced PiT1 expression levels also exhibited impaired proliferation. Together these results suggest that a certain level of PiT1 is important for proliferation. We have here investigated the role of PiT1 in regulation of cell proliferation using two strictly density-inhibited cells lines, the murine MC3T3-E1 and NIH3T3 cells. Results We found that knock-down of PiT1 in MC3T3-E1 cells led to impaired proliferation supporting that at least a certain level of PiT1 is important for wildtype level of proliferation. We, however, also observed that MC3T3-E1 and NIH3T3 cells themselves regulate their endogenous PiT1 mRNA levels with lower levels in general correlating with decreased proliferation/increased cell density. Moreover, over-expression of human PiT1 led to increased proliferation of both MC3T3-E1 and NIH3T3 cultures and resulted in higher cell densities in cultures of these two strictly density-inhibited cell lines. In addition, when we transformed NIH3T3 cells by cultivation in fetal bovine serum, cells over-expressing human PiT1 formed more colonies in soft agar than control cells. Conclusions We conclude that not only is a certain level of PiT1 necessary for normal cell division as suggested by previously published studies, rather the cellular PiT1 level is involved in regulating cell proliferation and cell density and an increased PiT1 expression can indeed make NIH3T3 cells more sensitive to

  16. Myocardial T1 and T2 mapping: Techniques and clinical applications

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Pan Ki; Hong, Yoo Jin; Im, Dong Jin [Dept. of Radiology and Research Institute of Radiological Science, Severance Hospital, Yonsei University College of Medicine, Seoul (Korea, Republic of); and others

    2017-01-15

    Cardiac magnetic resonance (CMR) imaging is widely used in various medical fields related to cardiovascular diseases. Rapid technological innovations in magnetic resonance imaging in recent times have resulted in the development of new techniques for CMR imaging. T1 and T2 image mapping sequences enable the direct quantification of T1, T2, and extracellular volume fraction (ECV) values of the myocardium, leading to the progressive integration of these sequences into routine CMR settings. Currently, T1, T2, and ECV values are being recognized as not only robust biomarkers for diagnosis of cardiomyopathies, but also predictive factors for treatment monitoring and prognosis. In this study, we have reviewed various T1 and T2 mapping sequence techniques and their clinical applications.

  17. Cardiac amyloidosis: MR imaging findings and T1 quantification, comparison with control subjects.

    Science.gov (United States)

    Krombach, Gabriele A; Hahn, Christa; Tomars, Maren; Buecker, Arno; Grawe, Armin; Günther, Rolf W; Kühl, Harald P

    2007-06-01

    In cardiac amyloidosis an interstitial deposition of amyloid fibrils causes concentric thickening of the atrial and ventricular walls. We describe the results of tissue characterization of the myocardium by T1 quantification and MRI findings in a patient with cardiac amyloidosis. The T1 time of the myocardium was elevated compared to that in individuals without amyloidosis. The T1 time of the myocardium was 1387 +/- 63 msec (mean value obtained from four measurements +/- standard deviation [SD]) in the patient with cardiac amyloidosis, while the reference value obtained from the myocardium of 10 individuals without known myocardial disease was 1083 +/- 33 msec (mean value +/- SD). In combination with other MR findings suggestive of amyloidosis, such as homogeneous thickening of the ventricular and atrial walls, thickening of the valve leaflets, restrictive filling pattern, and reduction of systolic function, T1 quantification may increase diagnostic confidence.

  18. T1 pseudohyperintensity on fat-suppressed MRI: A potential diagnostic pitfall

    Science.gov (United States)

    Huynh, Tuan N.; Johnson, D. Thor; Poder, Liina; Joe, Bonnie N.; Webb, Emily M.; Coakley, Fergus V.

    2011-01-01

    MRI findings in two patients with misleading T1 hyperintensity seen only on fat-suppressed images are presented, one with a renal cell carcinoma that was misinterpreted as a hemorrhagic cyst and the other with an ovarian serous cystadenocarcinoma that was misinterpreted as a complicated endometrioma. The apparent T1 hyperintensity on fat suppressed images in these cases was likely due to varying perception of image signal dependent on local contrast, an optical effect known as the checker-shadow illusion. T1 pseudohyperintensity should be considered when apparently high T1 signal intensity is seen only on fat-suppressed images; review of non fat-suppressed images may help prevent an erroneous diagnoses of blood-containing lesions. PMID:21765301

  19. Genetic Polymorphism in Glutathione Transferases (GST): Population distribution of GSTM1, T1, and P1 conjugating activity.

    Science.gov (United States)

    Ginsberg, Gary; Smolenski, Susan; Hattis, Dale; Guyton, Kathryn Z; Johns, Douglas O; Sonawane, Babasaheb

    2009-01-01

    Glutathione transferases (GST) catalyze the conjugation of glutathione (GSH) with electrophiles, many of which may otherwise interact with protein or DNA. In select cases such as halogenated solvents, GST-mediated conjugation may lead to a more toxic or mutagenic metabolite. Polymorphisms that exert substantial effects on GST function were noted in human populations for several isozymes. This analysis focuses on three well-characterized isozymes, GSTM1, T1, and P1, in which polymorphisms were extensively studied with respect to DNA adducts and cancer in molecular epidemiologic studies. The current review and analysis focused upon how polymorphisms in these GST contributed to population variability in GST function. The first step in developing this review was to characterize the influence of genotype on phenotype (enzyme function) and the frequency of the polymorphisms across major population groups for all three GST. This information was then incorporated into Monte Carlo simulations to develop population distributions of enzyme function. These simulations were run separately for GSTM1, T1, and P1, and also for the combination of these isozymes, to assess the possibility of overlapping substrate specificity. Monte Carlo simulations indicated large interindividual variability for GSTM1 and T1 due to the presence of the null (zero activity) genotype, which is common in all populations studied. Even for GSTM1 or T1 non-null individuals, there was considerable interindividual variability with a bimodal distribution of enzyme activity evident. GSTP1 polymorphisms are associated with somewhat less variability due to the absence of null genotypes. However, in all cases simulated, the estimated variability is sufficiently large to warrant consideration of GST function distributions in assessments involving GST-mediated activation or detoxification of xenobiotics. Ideally, such assessments would involve physiologically based toxicokinetic (PBTK) modeling to assess

  20. TU-EF-BRA-02: Longitudinal Proton Spin Relaxation and T1-Imaging

    Energy Technology Data Exchange (ETDEWEB)

    Lemen, L. [Univ Cincinnati (United States)

    2015-06-15

    can be introduced with either of two approaches. In the first, one thinks (loosely) of the nuclei of hydrogen atoms as (rotating and charged and therefore) magnetic objects, whose spin-axes tend to align in a strong external magnetic field, much like a compass needle. As with the Bohr atom, this spin-up/spin-down picture is a highly abridged version of the full quantum mechanical treatment, but still it leads to some useful, legitimate pictures of the NMR process occurring within a voxel: When RF photons of the correct (Larmor) frequency elevate protons in a fixed magnetic field out of their lower-energy spin state into the upper, the NMR phenomenon is indicated by the detectable absorption of RF power. With the addition of a linear gradient field along a multi-voxel, one-dimensional patient/phantom, as well, we can determine the water content of each compartment – an example of a real MRI study, albeit in 1D. Part I concludes with a discussion of the net magnetization at position x, m0(x), under conditions of dynamic thermal equilibrium, which leads into: Part II. Net Voxel Magnetization, m(x,t); T1-MRI; The MRI Device (Lemen), investigates the biophysics of the form of proton spin relaxation process characterized by the time T1. It then moves on to the creation of an MR image that displays the spatial variation in the values of this clinically relevant parameter, again in 1D. Finally, the design and workings of a clinical MRI machine are sketched, in preparation for: Part III. ‘Classical’ NMR; FID Imaging in 1D via k-Space (Yanasak) presents the second standard approach to NMR and MRI, the classical model. It focuses on the time dependence of the net nuclear magnetization, m(x,t), the overall magnetic field generated by the cohort of protons in the voxel at position x. Quite remarkably, this nuclear net magnetization itself acts in a strong magnetic field like a gyroscope in a gravitational field. This tack is better for explaining Free Induction Decay (FID

  1. Determination of T1- and T2-relaxation times in the spleen of patients with splenomegaly

    DEFF Research Database (Denmark)

    Thomsen, C; Josephsen, P; Karle, H

    1990-01-01

    Twenty-nine patients with known splenomegaly and seven healthy volunteers were examined. The T1 and T2 relaxation times were read out from a region of interest centrally in the spleen. Even though different mean T1 and T2 relaxation times were found between the groups, the great scatter and the c...... and the considerable overlap between the groups makes the contribution of relaxation time measurements to the differential diagnosis of splenomegaly of limited value....

  2. Entwicklung klinischer Methoden zur Quantifizierung der longitudinalen Relaxationszeit T1 in der MRT

    OpenAIRE

    Gensler, Daniel

    2016-01-01

    Die Aufgabenstellung in der vorliegenden Arbeit bestand in der Entwicklung und Umsetzung neuer T1-Quantifizierungsverfahren, die zuverlässig in der klinischen Routine angewendet werden können. Die ausgearbeiteten Techniken umfassten dabei zwei Hauptarbeitsschwerpunkte. Zum einen die Implementierung einer neuartigen dynamischen T1- Thermometriemethode für MR-Sicherheitsuntersuchungen medizinischer Geräte und Implantate, wie beispielsweise Kathetern oder Herzschrittmachern, und zum anderen d...

  3. RETRACTED: Relationship between the ACE I/D gene polymorphism and T1DN susceptibility/risk of T1DM developing into T1DN in the Caucasian population.

    Science.gov (United States)

    Zhou, Tian-Biao; Guo, Xue-Feng; Jiang, Zongpei; Li, Hong-Yan

    2015-12-01

    The following article has been included in a multiple retraction: Tian-Biao Zhou, Xue-Feng Guo, Zongpei Jiang, and Hong-Yan Li Relationship between the ACE I/D gene polymorphism and T1DN susceptibility/risk of T1DM developing into T1DN in the Caucasian population Journal of Renin-Angiotensin-Aldosterone System 1470320314563425, first published on February 1, 2015 doi: 10.1177/1470320314563425 This article has been retracted at the request of the Editors and the Publisher. After conducting a thorough investigation, SAGE found that the submitting authors of a number of papers published in the Journal of the Renin-Angiotensin Aldosterone System ( JRAAS) (listed below) had supplied fabricated contact details for their nominated reviewers. The Editors accepted these papers based on the reports supplied by the individuals using these fake reviewer email accounts. After concluding that the peer review process was therefore seriously compromised, SAGE and the journal Editors have decided to retract all affected articles. Online First articles (these articles will not be published in an issue) Wenzhuang Tang, Tian-Biao Zhou, and Zongpei Jiang Association of the angiotensinogen M235T gene polymorphism with risk of diabetes mellitus developing into diabetic nephropathy Journal of Renin-Angiotensin-Aldosterone System 1470320314563426, first published on December 18, 2014 doi: 10.1177/1470320314563426 Tian-Biao Zhou, Hong-Yan Li, Zong-Pei Jiang, Jia-Fan Zhou, Miao-Fang Huang, and Zhi-Yang Zhou Role of renin-angiotensin-aldosterone system inhibitors in radiation nephropathy Journal of Renin-Angiotensin-Aldosterone System 1470320314563424, first published on December 18, 2014 doi: 10.1177/1470320314563424 Weiqiang Zhong, Zongpei Jiang, and Tian-Biao Zhou Association between the ACE I/D gene polymorphism and T2DN susceptibility: The risk of T2DM developing into T2DN in the Asian population Journal of Renin-Angiotensin-Aldosterone System 1470320314566019, first published on January

  4. Cardiac Fibrosis in Aortic Stenosis and Hypertensive Heart Disease Assessed by Magnetic Resonance T1 Mapping.

    Science.gov (United States)

    von Knobelsdorff-Brenkenhoff, Florian; Mueller, Anna-Katharina; Prothmann, Marcel; Hennig, Pierre; Dieringer, Matthias A; Schmacht, Luisa; Greiser, Andreas; Schulz-Menger, Jeanette

    2016-09-01

    Continuous pressure overload may lead to subclinical myocardial tissue changes in patients with hypertensive heart disease (HHD) and aortic stenosis (AS). The study aim was to detect interstitial fibrosis using quantitative cardiovascular magnetic resonance. Fifteen patients with HHD (arterial hypertension + septal wall thickness ≥13 mm), 33 with AS (eight mild, 15 moderate, 10 severe), and 60 healthy controls were enrolled. Native T1 maps (modified Look-Locker inversion recovery) were obtained in a basal, mid-ventricular, and apical shortaxis slice of the left ventricle to assess cardiac fibrosis. Focal fibrosis was assessed with late gadolinium enhancement (LGE). Patients with HHD and controls did not differ regarding the native myocardial T1 values, both per slice and per segment. In AS patients, apical native T1 values were lower than in controls, and there was a trend towards higher T1 values in the septum in severe AS (1172.6 ± 62.0 ms versus 1152.9 ± 43.9 ms). Five HHD patients and 11 AS patients had non-ischemic fibrosis in LGE images. Native T1 times did not differ between LGE-positive and LGEnegative groups (both with inclusion and exclusion of segments with LGE). T1 mapping did not reveal any evidence of abnormal interstitial fibrosis in HHD subjects with mild hypertrophy. In severe AS, a trend towards more interstitial fibrosis was present, but absolute differences were small for decision making.

  5. T1 ρ-weighted MRI using a surface coil to transmit spin-lock pulses

    Science.gov (United States)

    Borthakur, Arijitt; Charagundla, Sridhar R.; Wheaton, Andrew; Reddy, Ravinder

    2004-04-01

    T1 ρ-weighted MRI is a novel basis for generating tissue contrast. However, it suffers from sensitivity to B1 inhomogeneity. First, excitation with a spatially varying B1 causes flip-angle artifacts and second, spin locking with an inhomogeneous B1 results in non-uniform T1 ρ contrast. In this study, we overcome the former complication with a specially designed spin-locking pulse sequence and we successfully obtain T1 ρ-weighted images with a surface coil. In this pulse sequence, the spin-lock pulse was divided into segments of equal duration and alternating phase. This "self-compensating" T1 ρ-preparatory pulse sequence was analyzed and the effect of an inhomogeneous B1 field was simulated using the Bloch equations. T1 ρ-weighted MR images of a phantom and a human knee joint in vivo were obtained on a clinical scanner with a surface coil to demonstrate the utility of the pulse sequence. The self-compensating T1 ρ-prepared pulses sequence resulted in substantially reduced image artifacts compared to the conventional, single-phase spin-lock pulse.

  6. Glioblastoma: does the pre-treatment geometry matter? A postcontrast T1 MRI-based study

    Energy Technology Data Exchange (ETDEWEB)

    Perez-Beteta, Julian; Martinez-Gonzalez, Alicia; Molina, David; Amo-Salas, Mariano; Luque, Belen; Perez-Garcia, Victor M. [Universidad de Castilla-La Mancha, Laboratory of Mathematical Oncology, Edificio Politecnico, Instituto de Matematica Aplicada a la Ciencia y la Ingenieria, Ciudad Real (Spain); Arregui, Elena; Calvo, Manuel; Borras, Jose M.; Lopez, Carlos; Claramonte, Marta [Hospital General de Ciudad Real, Ciudad Real (Spain); Barcia, Juan A.; Iglesias, Lidia; Avecillas, Josue [Hospital Clinico San Carlos, Madrid (Spain); Albillo, David; Navarro, Miguel; Villanueva, Jose M.; Paniagua, Juan C.; Perez-Romasanta, Luis [Hospital Universitario de Salamanca, Salamanca (Spain); Martino, Juan; Velasquez, Carlos [Hospital Marques de Valdecilla, Santander (Spain); Asenjo, Beatriz; Benavides, Manuel; Herruzo, Ismael [Hospital Carlos Haya, Malaga (Spain); Delgado, Maria del Carmen; Valle, Ana del [Universidad de Sevilla, Facultad de Matematicas, Sevilla (Spain); Falkov, Anthony [Auckland Radiation Oncology, Auckland (New Zealand); Schucht, Philippe [Bern Inselspital, Neurosurgery Department, Bern (Switzerland); Arana, Estanislao [Instituto Valenciano de Oncologia, Valencia (Spain)

    2017-03-15

    The potential of a tumour's volumetric measures obtained from pretreatment MRI sequences of glioblastoma (GBM) patients as predictors of clinical outcome has been controversial. Mathematical models of GBM growth have suggested a relation between a tumour's geometry and its aggressiveness. A multicenter retrospective clinical study was designed to study volumetric and geometrical measures on pretreatment postcontrast T1 MRIs of 117 GBM patients. Clinical variables were collected, tumours segmented, and measures computed including: contrast enhancing (CE), necrotic, and total volumes; maximal tumour diameter; equivalent spherical CE width and several geometric measures of the CE ''rim''. The significance of the measures was studied using proportional hazards analysis and Kaplan-Meier curves. Kaplan-Meier and univariate Cox survival analysis showed that total volume [p = 0.034, Hazard ratio (HR) = 1.574], CE volume (p = 0.017, HR = 1.659), spherical rim width (p = 0.007, HR = 1.749), and geometric heterogeneity (p = 0.015, HR = 1.646) were significant parameters in terms of overall survival (OS). Multivariable Cox analysis for OS provided the later two parameters as age-adjusted predictors of OS (p = 0.043, HR = 1.536 and p = 0.032, HR = 1.570, respectively). Patients with tumours having small geometric heterogeneity and/or spherical rim widths had significantly better prognosis. These novel imaging biomarkers have a strong individual and combined prognostic value for GBM patients. (orig.)

  7. Volumetric T1 and T2 magnetic resonance brain toolkit for relaxometry mapping simulation

    Directory of Open Access Journals (Sweden)

    Antonio Carlos da Silva Senra Filho

    Full Text Available Abstract Introduction Relaxometry images are an important magnetic resonance imaging (MRI technique in the clinical routine. Many diagnoses are based on the relaxometry maps to infer abnormal state in the tissue characteristic relaxation constant. In order to study the performance of these image processing approaches, a controlled simulated environment is necessary. However, a simulated relaxometry image tool is still lacking. This study proposes a computational anatomical brain phantom for MRI relaxometry images, which aims to offer an easy and flexible toolkit to test different image processing techniques, applied to MRI relaxometry maps in a controlled simulated environment. Methods A pipeline of image processing techniques such as brain extraction, image segmentation, normalization to a common space and signal relaxation decay simulation, were applied to a brain structural ICBM brain template, on both T1 and T2 weighted images, in order to simulate a volumetric brain relaxometry phantom. The FMRIB Software Library (FSL toolkits were used here as the base image processing needed to all the relaxometry reconstruction. Results All the image processing procedures are performed using automatic algorithms. In addition, different artefact levels can be set from different sources such as Rician noise and radio-frequency inhomogeneity noises. Conclusion The main goal of this project is to help researchers in their future image processing analysis involving MRI relaxometry images, offering reliable and robust brain relaxometry simulation modelling. Furthermore, the entire pipeline is open-source, which provides a wide collaboration between researchers who may want to improve the software and its functionality.

  8. Improvement of Thermal Stability via Outer-Loop Ion Pair Interaction of Mutated T1 Lipase from Geobacillus zalihae Strain T1

    Directory of Open Access Journals (Sweden)

    Mahiran Basri

    2012-01-01

    Full Text Available Mutant D311E and K344R were constructed using site-directed mutagenesis to introduce an additional ion pair at the inter-loop and the intra-loop, respectively, to determine the effect of ion pairs on the stability of T1 lipase isolated from Geobacillus zalihae. A series of purification steps was applied, and the pure lipases of T1, D311E and K344R were obtained. The wild-type and mutant lipases were analyzed using circular dichroism. The Tm for T1 lipase, D311E lipase and K344R lipase were approximately 68.52 °C, 70.59 °C and 68.54 °C, respectively. Mutation at D311 increases the stability of T1 lipase and exhibited higher Tm as compared to the wild-type and K344R. Based on the above, D311E lipase was chosen for further study. D311E lipase was successfully crystallized using the sitting drop vapor diffusion method. The crystal was diffracted at 2.1 Å using an in-house X-ray beam and belonged to the monoclinic space group C2 with the unit cell parameters a = 117.32 Å, b = 81.16 Å and c = 100.14 Å. Structural analysis showed the existence of an additional ion pair around E311 in the structure of D311E. The additional ion pair in D311E may regulate the stability of this mutant lipase at high temperatures as predicted in silico and spectroscopically.

  9. Is the T1ρ MRI profile of hyaline cartilage in the normal hip uniform?

    Science.gov (United States)

    Rakhra, Kawan S; Cárdenas-Blanco, Arturo; Melkus, Gerd; Schweitzer, Mark E; Cameron, Ian G; Beaulé, Paul E

    2015-04-01

    T1ρ MRI is an imaging technique sensitive to proteoglycan (PG) content of hyaline cartilage. However, normative T1ρ values have not been established for the weightbearing cartilage of the hip, and it is not known whether it is uniform or whether there is topographic variation. Knowledge of the T1ρ profile of hyaline cartilage in the normal hip is important for establishing a baseline against which comparisons can be made to experimental and clinical arthritic subjects. In this diagnostic study, we determined (1) the T1ρ MRI values of hyaline cartilage of the normal hip; and (2) whether the T1ρ MRI profile of the normal hip hyaline cartilage is uniform. Fourteen asymptomatic volunteers (11 men, three women; mean age, 35 years) prospectively underwent 1.5-T T1ρ MRI of a single hip. The weightbearing hyaline cartilage bilayer of the acetabulum and femoral head was evaluated on sagittal images and segmented into four zones: (1) anterior; (2) anterosuperior; (3) posterosuperior; and (4) and posterior. For the full region of interest and within each zone and each sagittal slice, we calculated the mean T1ρ relaxation value, a parameter that indirectly quantifies PG content, where T1ρ is inversely related to PG concentration. There was variation in the T1ρ relaxation values depending on zone (anterior to posterior) and slice (medial to lateral). When combining the most anterior quadrants (Zones 1 and 2), the T1ρ relaxation values were lower than those in the combined posterior quadrants (Zones 3 and 4) (30.4 msec versus 32.2 msec, respectively; p = 0.002), reflecting higher PG concentration. There was a difference between the T1ρ relaxation values of the sagittal slices (p = 0.038), most pronounced anteriorly in Zone 1 (26.6 msec, p = 0.001). With a selective combination of zones and slices, there were lower mean T1ρ values in the anterolateral-most region compared with the remainder of the weightbearing portion of the hip (28.6 msec versus 32.2 msec

  10. A classical description of relaxation of interacting pairs of unlike spins: Extension to T1 ϱ, T2, and T1 ϱoff, including contact interactions

    Science.gov (United States)

    Konig, Seymour H.

    A novel derivation of the equations that describe the spin-lattice magnetic relaxation of nuclear spin moments, in liquids, resulting from magnetic dipolar interactions with neighboring paramagnetic ions, the Solomon-Bloembergen-Morgan equations was previously presented (S. H. Koenig, J. Magn. Reson.31, 1 (1978)). The derivation involves a computation of the dissipative energy flow from the nuclear spins to the lattice rather than a computation of the lattice-produced fluctuations of the local field at the nuclear spins. Two advantages accrue: (1) the spectral densities that enter into the relaxation expressions can be directly related to well-defined absorption transitions and relaxation processes of the paramagnetic ions, clarifying the physical processes that produce relaxation, and (2) the derivation can be readily generalized to paramagnetic ions with arbitrary spin Hamiltonian, and to deviations of their susceptibility from Curie law behavior. The derivation is extended to include relaxation in liquids in the rotating frame: the on resonance T1 ϱ which reduces to T2 for small amplitude radiofrequency fields; and the off resonance T1 ϱoff, which reduces to T1. The results, which are given for contact as well as dipolar interactions, also describe relaxation of 13C and 15N nuclei by protons under conditions of proton-decoupling, a situation becoming increasingly important in the study of biological macromolecules by high-resolution NMR spectroscopy.

  11. T1 mapping定量技术评价左室不同区域心肌初始T1值的初步研究%A Preliminary Study of the Quantitative T1 Mapping Technique in Evaluation of the Native Left Ventricular Myocardial T1 Value in Different Segments

    Institute of Scientific and Technical Information of China (English)

    刘明熙; 祝红线; 刘洁; 张挽时; 张子衡; 周振宇; 解立志; 孟利民; 徐先荣; 田建伟; 龚万沣

    2015-01-01

    Objectives To investigate the clinical feasibility and repeatability of a MLLSR [Modified Look-Locker FIESTA (Fast Imaging Employing Steady State Acquisition) Imaging with Saturation Recovery]-based quantitative T1 mapping technique in 3.0T CMR (Cardiac Magnetic Resonance) to evaluate the left ventricular myocardial T1native values in different segments.Methods Altogether 30 healthy volunteers were selected and scanned by CMR on the sequence of Cine imaging, T2WI and T1 mapping so as to perform quantitative measurement of ROI (Region of Interest) T1native values. Then, the independent-samplesT test and ANOVA (Analysis of Variance) were deployed to analyze the difference of the T1native values in 17 segments of myocardium, different coronary arterial blood supply areas, age and gender.Results There were differences of the T1native values between some segmental myocardia(P<0.01). The mean myocardial T1native and T1native of blood pool were:(717.6±100.6) ms and (1208.9±224.2) ms at the base; (773.9±101.2) ms and (1281.2±251.7) ms in the middle; (955.4±191.1) ms and (1829.6±584.8) ms at the apex, respectively. Apical T1native values of myocardium and blood pool were higher than the basal and the middle (P<0.01). Also, statistically significant differences (F=47.862,P<0.01) existed in T1native values of different coronary arterial blood supply areas.Conclusion The CMR MLLSR T1 mapping technique had demonstrated its excellent feasibility and repeatability, which revealed segmented variations in evaluation of left ventricular myocardial T1native values.%目的:探讨3.0T心脏磁共振(CMR)检查中基于改进的Look-Locker稳态自由进动饱和恢复序列(MLLSR)的T1 mapping定量技术的可行性和可重复性,并评价左室不同区域心肌初始T1值以供参考。方法选取30例健康志愿者,分别行心脏Cine电影、T2WI序列、T1 mapping序列扫描,测定感兴趣区初始T1值,应用独立样本t检验和方差

  12. Modulation of t1alpha expression with alveolar epithelial cell phenotype in vitro.

    Science.gov (United States)

    Borok, Z; Danto, S I; Lubman, R L; Cao, Y; Williams, M C; Crandall, E D

    1998-07-01

    T1alpha is a recently identified gene expressed in the adult rat lung by alveolar type I (AT1) epithelial cells but not by alveolar type II (AT2) epithelial cells. We evaluated the effects of modulating alveolar epithelial cell (AEC) phenotype in vitro on T1alpha expression using either soluble factors or changes in cell shape to influence phenotype. For studies on the effects of soluble factors on T1alpha expression, rat AT2 cells were grown on polycarbonate filters in serum-free medium (MDSF) or in MDSF supplemented with either bovine serum (BS, 10%), rat serum (RS, 5%), or keratinocyte growth factor (KGF, 10 ng/ml) from either day 0 or day 4 through day 8 in culture. For studies on the effects of cell shape on T1alpha expression, AT2 cells were plated on thick collagen gels in MDSF supplemented with BS. Gels were detached on either day 1 (DG1) or day 4 (DG4) or were left attached until day 8. RNA and protein were harvested at intervals between days 1 and 8 in culture, and T1alpha expression was quantified by Northern and Western blotting, respectively. Expression of T1alpha progressively increases in AEC grown in MDSF +/- BS between day 1 and day 8 in culture, consistent with transition toward an AT1 cell phenotype. Exposure to RS or KGF from day 0 prevents the increase in T1alpha expression on day 8, whereas addition of either factor from day 4 through day 8 reverses the increase. AEC cultured on attached gels express high levels of T1alpha on days 4 and 8. T1alpha expression is markedly inhibited in both DG1 and DG4 cultures, consistent with both inhibition and reversal of the transition toward the AT1 cell phenotype. These results demonstrate that both soluble factors and alterations in cell shape modulate T1alpha expression in parallel with AEC phenotype and provide further support for the concept that transdifferentiation between AT2 and AT1 cell phenotypes is at least partially reversible.

  13. MRI detection of hypointense brain lesions in patients with multiple sclerosis: T1 spin-echo vs. gradient-echo

    Energy Technology Data Exchange (ETDEWEB)

    Dupuy, Sheena L.; Tauhid, Shahamat; Kim, Gloria; Chu, Renxin; Tummala, Subhash [Departments of Neurology, Brigham and Women' s Hospital, Laboratory for Neuroimaging Research, Partners MS Center, Harvard Medical School, Boston, MA (United States); Hurwitz, Shelley [Departments of Medicine, Brigham and Women' s Hospital, Harvard Medical School, Boston, MA (United States); Bakshi, Rohit, E-mail: rbakshi@bwh.harvard.edu [Departments of Neurology, Brigham and Women' s Hospital, Laboratory for Neuroimaging Research, Partners MS Center, Harvard Medical School, Boston, MA (United States); Departments of Radiology, Brigham and Women' s Hospital, Harvard Medical School, Boston, MA (United States)

    2015-08-15

    Highlights: • Compared T1SE and T1GE in detecting hypointense brain lesions in MS patients. • T1GE detected a higher cerebral lesion volume and number than T1SE. • T1SE correlated significantly with disability, while T1GE did not. • Hypointense lesions on T1SE and T1GE are not interchangeable in patients with MS. - Abstract: Objective: Compare T1 spin-echo (T1SE) and T1 gradient-echo (T1GE) sequences in detecting hypointense brain lesions in multiple sclerosis (MS). Background: Chronic hypointense lesions on T1SE MRI scans are a surrogate of severe demyelination and axonal loss in MS. The role of T1GE images in the detection of such lesions has not been clarified. Design/methods: In 45 patients with MS [Expanded Disability Status Scale (EDSS) score (mean ± SD) 3.5 ± 2.0; 37 relapsing-remitting (RR); 8 secondary progressive (SP)], cerebral T1SE, T1GE, and T2-weighted fluid-attenuated inversion-recovery (FLAIR) images were acquired on a 1.5 T MRI scanner. Images were re-sampled to axial 5 mm slices before directly comparing lesion detectability using Jim (v.7, Xinapse Systems). Statistical methods included Wilcoxon signed rank tests to compare sequences and Spearman correlations to test associations. Results: Considering the entire cohort, T1GE detected a higher lesion volume (5.90 ± 6.21 vs. 4.17 ± 4.84 ml, p < 0.0001) and higher lesion number (27.82 ± 20.66 vs. 25.20 ± 20.43, p < 0.05) than T1SE. Lesion volume differences persisted when considering RR and SP patients separately (both p < 0.01). A higher lesion number by T1GE was seen only in the RR group (p < 0.05). When comparing correlations between lesion volume and overall neurologic disability (EDSS score), T1SE correlated with EDSS (Spearman r = 0.29, p < 0.05) while T1GE (r = 0.23, p = 0.13) and FLAIR (r = 0.24, p = 0.12) did not. Conclusion: Our data suggest that hypointense lesions on T1SE and T1GE are not interchangeable in patients with MS. Based on these results, we hypothesize that T1GE

  14. T1G3膀胱癌二次电切治疗体会%Repeat Transurethral Resection for Bladder Cancer T1G3

    Institute of Scientific and Technical Information of China (English)

    吴慧玲; 戴国平; 杜小文

    2012-01-01

    [Purpose] To investigate the necessity of repeat transurethral resection (ReTUR) for patients with bladder cancer T1G3. [Methods] Thirty-seven patients with bladder cancer T1G3 after transurethral resection of bladder tumor (TURBt) were analyzed retrospectively. The primary bladder cancers were classified as solitary papillary tumor (15 cases), multiple papillary tumor (17 cases) and sessile lesions (5 eases).Ali cases underwent ReTUR following primary surgery within 4 ~6 weeks and postoperative mitomycin infusion chemotherapy. [Results]All the resected tumor specimens contained muscular layer tissues. Residual tumors were found in 13 cases (13/37,35.1%) at the ReTUR,and 2 cases (2/37,5.4%) were diagnosed as stage T2 and adjusted the treatment plan. One case (1/15,6.7%)with solitary papillary,8 cases(8/17,47.1%)with multiple papillary and 4 cases (4/5,80.0%) with sessile lesions had residual cancer cells, respectively. [Conclusions] Different T1G3 bladder cancer patients have different outcomes after ReTUR. For patients with multiple papillary and sessile T3G3 lesions, routinely performed ReTUR are necessary. While ReTUR is necessary or not for the patients with solitary papillary T1G3 tumors should be considered accordingly.%[目的]探讨T1G3膀胱癌行第二次经尿道电切术(ReTUR)的必要性.[方法]回顾性分析37例经尿道膀胱肿瘤电切术(TURBt)明确为T1G3膀胱癌患者资料.单发乳头状肿瘤15例,多发乳头状肿瘤17例,广基型肿瘤5例.4~6周后再次电切,术后常规丝裂霉素膀胱内灌注化疗.[结果]所有肿瘤切除标本均含有肌层组织.二次电切中13例(13/37,35.1%)发现有残余肿瘤,2例(2/37,5.4%)发现肿瘤为T2期,更改治疗方案.1例(1/15,6.7%)单发乳头状肿瘤,8例(8/17,47.1%)多发乳头状肿瘤,4例(4/5,80.0%)广基型肿瘤发现癌细胞残留.[结论]不同的T1G3患者在二次电切中结果不尽相同.对多发乳头状和广基型的肿

  15. Fat-saturated post gadolinium T1 imaging of the brain in multiple sclerosis

    Energy Technology Data Exchange (ETDEWEB)

    Al-Saeed, Osama; Sheikh, Mehraj (Dept. of Radiology, Kuwait Univ. (Kuwait)), email: osamas@hsc.edu.kw; Ismail, Mohammed (Ibn Sina Hospital (Kuwait)); Athyal, Reji (Amiri Hospital (Kuwait))

    2011-06-15

    Background Magnetic resonance imaging (MRI) is of vital importance in the diagnosis and follow-up of patients with multiple sclerosis (MS). Imaging sequences better demonstrating enhancing lesions can help in detecting active MS plaques. Purpose To evaluate the role of fat-saturated gadolinium-enhanced T1-weighted (T1W) images of the brain in MS and to assess the benefit of performing this additional sequence in the detection of enhancing lesions. Material and Methods In a prospective study over a six-month period, 70 consecutive patients with clinically diagnosed MS were enrolled. These constituted 14 male and 56 female patients between the ages of 21 and 44 years. All the patients underwent brain MRIs on a 1.5 Tesla Magnet. Gadolinium-enhanced T1 images with and without fat saturation were compared and results were recorded and analyzed using a conspicuity score and McNemar test. Results There were a total of 157 lesions detected in 70 patients on post-contrast T1W fat-saturated images compared with 139 lesions seen on the post-contrast T1W fast spin-echo (FSE) images. This was because 18 of the lesions (11.5%) were only seen on the fat-saturated images. In addition, 15 lesions were more conspicuous on the fat saturation sequence (9.5%). The total conspicuity score obtained, including all the lesions, was 2.24 +/-0.60 (SD). Using the two-tailed McNemar test for quantitative analysis, the P value obtained was <0.0001. Conclusion T1W fat-saturated gadolinium-enhanced images show better lesion enhancement than T1W images without fat saturation

  16. Characterization of a novel telomerase-immortalized human endometrial stromal cell line, St-T1b

    Directory of Open Access Journals (Sweden)

    Brosens Jan J

    2009-07-01

    progesterone. St-T1b cells therefore serve as a useful model for primary ESC.

  17. The Relationship between T1 Sagittal Angle and Sagittal Balance: A Retrospective Study of 119 Healthy Volunteers

    OpenAIRE

    2016-01-01

    T1 sagittal angle has been reported to be used as a parameter for assessing sagittal balance and cervical lordosis. However, no study has been performed to explore the relationship between T1 sagittal angle and sagittal balance, and whether T1 sagittal angle could be used for osteotomy guidelines remains unknown. The aim of our study is to explore the relationship between T1 sagittal angle and sagittal balance, determine the predictors for T1 sagittal angle, and determine whether T1 sagittal ...

  18. Discovery of a 6/sup -/, T=1 resonance in /sup 24/Mg via high-resolution inelastic electron scattering

    Energy Technology Data Exchange (ETDEWEB)

    Zarek, H.; Pich, B.O.; Drake, T.E.; Rowe, D.J.; Bertozzi, W.; Creswell, C.; Hirsch, A.; Hynes, M.V.; Kowalski, S.; Norum, B.; Rad, F.N.; Sargent, C.P.; Williamson, C.F.; Lindgren, R.A.

    1977-04-04

    The unique high-resolution and high-energy features of the electron-scattering facility at the MIT-Bates Accelerator were used to locate a dominant narrow resonance at 15.045 +- 0.035 MeV in /sup 24/Mg. A spin-parity assignment of 6/sup -/ and an isospin T=1 assignment were made. The M6 form factor was measured and compared to the prediction of a theoretical calculation which uses the open-shell random-phase approximation on a shell-model ground state for /sup 24/Mg.

  19. T1 mapping for detection of left ventricular myocardial fibrosis in hypertrophic cardiomyopathy: A preliminary study

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Minjie [Department of Radiology, State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing (China); Zhao, Shihua, E-mail: coolkan@163.com [Department of Radiology, State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing (China); Yin, Gang; Jiang, Shiliang; Zhao, Tao; Chen, Xiuyu [Department of Radiology, State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing (China); Tian, Liangxin [Department of Cardiac Surgery, State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing (China); Zhang, Yan; Wei, Yunqing; Liu, Qiong [Department of Radiology, State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing (China); He, Zuoxiang [Department of Nuclear Medicine, State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing (China); Xue, Hui [Siemens Healthcare, 737 N. Michigan Avenue, Suite 1600 Chicago, IL 60611 (United States); An, Jing [Siemens Shenzhen Magnetic Resonance Ltd. Application Dept. Siemens MRI center, Gaoxin C. Ave.,2nd, Hi-Tech Industrial Park, Shenzhen (China); Shah, Saurabh [Siemens Healthcare, 737 N. Michigan Avenue, Suite 1600 Chicago, IL 60611 (United States)

    2013-05-15

    Purpose: To investigate the diagnostic value of T1 mapping imaging of evaluating fibrosis in patients with hypertrophic cardiomyopathy (HCM). Materials and methods: 21 subjects with HCM and 18 healthy volunteers underwent conventional late gadolinium enhancement (LGE) imaging and T1 mapping imaging. The region of myocardium in HCM is divided into remote area of LGE, peri-LGE, LGE (halo-like LGE and typical patchy LGE). These regions combined with normal volunteers’ myocardium were calculated by the reduced percent of T1 value (RPTV). Results: The RPTV in healthy volunteers was no significant comparing with that in the remote area of LGE in HCM subjects (3.98 ± 3.19 vs. 3.34 ± 2.75, P > 0.05). There were significant statistical differences in pairwise among the remote area of LGE, peri-LGE, halo-like LGE and typical patchy LGE in the RPTV (P < 0.0001). ROC curves indicated that the T1 mapping imaging has a greater area under the curve comparing with that of traditional LGE imaging (0.975 ± 0.07 vs. 0.753 ± 0.26, P < 0.0001). Conclusions: HCM has a high prevalence of fibrosis and with varying severity. T1 mapping imaging can be a useful method to evaluate the severity of the fibrosis in HCM.

  20. Differential diagnosis and prognosis of T1-weighted post-gadolinium intralabyrinthine hyperintensities

    Energy Technology Data Exchange (ETDEWEB)

    Dubrulle, F.; Puech, P.; Ernst, O. [University Nord of France, Department of Radiology, CHU Lille, Huriez Hospital INSERM, Lille (France); Kohler, R. [CHU Lille, Huriez Hospital, Department of Radiology, Lille (France); Vincent, C. [CHU Lille, Department of Otology and Oto-neurosurgery, Lille (France)

    2010-11-15

    The aim of this longitudinal study is to describe the different intralabyrinthine lesions yielding high signal intensity on T1-weighted (T1W) images after intravenous gadolinium and then to analyze the follow-up of these patients. Thirty-seven patients were included and followed clinically and radiologically. A precise analysis of MR labyrinthine signals allowed exact depiction of the different lesions. Special interest is focused on the intralabyrinthine fluid signal on 3D high-resolution T2W images. The enhanced T1W labyrinthine hyperintensities correspond to two different categories: intralabyrinthine enhancement (15 intralabyrinthine schwannomas, 13 labyrinthitis, 1 inflammatory granuloma) and spontaneous T1W hyperintensities (8 intralabyrinthine hemorrhages). Hemorrhagic lesions show a substantial decrease of the intralabyrinthine fluid signal on the 3D HRT2 that evolves to ossification. In labyrinthitis, the importance of the initial labyrinthine fluid signal decrease on the 3D HRT2 is well correlated with the hearing prognosis. A meticulous analysis of inner ear lesions allows various intralabyrinthine lesions, in particular schwannomas, to be differentiated from labyrinthitis. T1W imaging without gadolinium is essential for the correct diagnosis of rapidly evolving hearing loss. In labyrinthitis and intralabyrinthine hemorrhage, 3D HRT2 brings an interesting prognostic factor for the chance of hearing recovery. (orig.)

  1. Quantitative DLA-based compressed sensing for T1-weighted acquisitions

    Science.gov (United States)

    Svehla, Pavel; Nguyen, Khieu-Van; Li, Jing-Rebecca; Ciobanu, Luisa

    2017-08-01

    High resolution Manganese Enhanced Magnetic Resonance Imaging (MEMRI), which uses manganese as a T1 contrast agent, has great potential for functional imaging of live neuronal tissue at single neuron scale. However, reaching high resolutions often requires long acquisition times which can lead to reduced image quality due to sample deterioration and hardware instability. Compressed Sensing (CS) techniques offer the opportunity to significantly reduce the imaging time. The purpose of this work is to test the feasibility of CS acquisitions based on Diffusion Limited Aggregation (DLA) sampling patterns for high resolution quantitative T1-weighted imaging. Fully encoded and DLA-CS T1-weighted images of Aplysia californica neural tissue were acquired on a 17.2T MRI system. The MR signal corresponding to single, identified neurons was quantified for both versions of the T1 weighted images. For a 50% undersampling, DLA-CS can accurately quantify signal intensities in T1-weighted acquisitions leading to only 1.37% differences when compared to the fully encoded data, with minimal impact on image spatial resolution. In addition, we compared the conventional polynomial undersampling scheme with the DLA and showed that, for the data at hand, the latter performs better. Depending on the image signal to noise ratio, higher undersampling ratios can be used to further reduce the acquisition time in MEMRI based functional studies of living tissues.

  2. Dispersion of T1 and T2 nuclear magnetic resonance relaxation in crude oils.

    Science.gov (United States)

    Chen, Joseph J; Hürlimann, Martin; Paulsen, Jeffrey; Freed, Denise; Mandal, Soumyajit; Song, Yi-Qiao

    2014-09-15

    Crude oils, which are complex mixtures of hydrocarbons, can be characterized by nuclear magnetic resonance diffusion and relaxation methods to yield physical properties and chemical compositions. In particular, the field dependence, or dispersion, of T1 relaxation can be used to investigate the presence and dynamics of asphaltenes, the large molecules primarily responsible for the high viscosity in heavy crudes. However, the T2 relaxation dispersion of crude oils, which provides additional insight when measured alongside T1, has yet to be investigated systematically. Here we present the field dependence of T1-T2 correlations of several crude oils with disparate densities. While asphaltene and resin-containing crude oils exhibit significant T1 dispersion, minimal T2 dispersion is seen in all oils. This contrasting behavior between T1 and T2 cannot result from random molecular motions, and thus, we attribute our dispersion results to highly correlated molecular dynamics in asphaltene-containing crude oils. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Routine daily physical activity and glucose variations are strongly coupled in adults with T1DM.

    Science.gov (United States)

    Farabi, Sarah S; Carley, David W; Cinar, Ali; Quinn, Lauretta

    2015-12-01

    Type 1 Diabetes (T1DM) is characterized by altered glucose homeostasis resulting in wide glucose variations throughout a 24-h period. The relationship between routine daily physical activity and glucose variations has not been systematically investigated in adults with T1DM. The objectives of this study were to characterize and quantify the relationship between routine daily activity and glucose variations in a small group of adults with T1DM. Adults with T1DM treated with an insulin pump were recruited for the study. Over a 3-day period, glucose variations were monitored with a continuous glucose monitoring system (CGMS) and routine daily physical activity was assessed using an accelerometer-based physical activity-monitoring band. Simultaneous glucose and physical activity data for one 24-h period were used for analysis. Cross-correlation function and wavelet coherence analyses were employed to quantify the coupling between physical activity and glucose. Twelve subjects were included in the analysis. Cross-correlation function analysis revealed strong coupling between activity and glucose. Wavelet Coherence demonstrated that slower oscillations (120-340 min) of glucose and physical activity exhibited significantly greater coherence (F = 12.6, P < 0.0001) than faster oscillations (10 and 120 min). Physical activity and glucose demonstrate strong time and frequency-dependent coupling throughout a 24-h time period in adults with T1DM.

  4. Severe Facet Joint Arthrosis Caused C7/T1 Myelopathy: A Case Report

    Directory of Open Access Journals (Sweden)

    Toshimi Aizawa

    2009-01-01

    Full Text Available Cervical myelopathy is caused by degenerative processes of the spine including intervertebral disc herniation and posterior spur usually developing at C3/4 to C5/6. C7/T1 single level myelopathy is very rare because of the anatomical characteristics. Facet joint arthrosis can be a cause of cervical myelopathy but only a few cases have been reported. The authors report an extremely rare case of C7/T1 myelopathy caused by facet joint arthrosis. A 58-year-old male presented with hand and gait clumsiness. The radiological examinations revealed severe C7/T1 facet joint arthrosis with bony spur extending into the spinal canal, which compressed the spinal cord laterally. The T1 spinous process indicated nonunion of a “clay-shoveler's” fracture, which suggested that his cervico-thoracic spine had been frequently moved, and thus severe arthrosis had occurred in the facet joints. A right hemilaminectomy of C7 and C7/T1 facetectomy with single level spinal fusion led to complete neurological improvement.

  5. The role of glutathione S-transferase M1 and T1 gene polymorphisms and fruit and vegetable consumption in antioxidant parameters in healthy subjects.

    Science.gov (United States)

    Yuan, Lin-Hong; Meng, Li-Ping; Ma, Wei-Wei; Li, Sheng; Feng, Jin-Fang; Yu, Huan-Ling; Xiao, Rong

    2012-03-01

    The correlation of glutathione S-transferase (GST) M1/T1 genetic polymorphisms with oxidative stress-related chronic diseases was proved recently. The aim of the present study was to investigate the association of GSTM1/T1 genetic polymorphisms with antioxidant biomarkers and consumption of fruits and vegetables (F&V) in healthy subjects. In this study, for conducting a 3 d dietary survey, 190 healthy adults were recruited. After DNA extraction, a multiple PCR method was used for GSTM1/T1 genotyping. A spectrophotometer method was applied for the determination of plasma total antioxidant capacity (T-AOC), vitamin C level and erythrocyte GST enzyme activity. A general linear model was used to compare the mean values of antioxidant parameters for different GSTM1/T1 genotypes and consumption of F&V. Polymorphisms of GSTM1/T1 had no effects on plasma T-AOC and vitamin C levels. Deletion of the GSTM1 gene decreased the erythrocyte GST activity. There was correlation between plasma T-AOC and consumption of F&V in the GSTM1⁻ or GSTT1⁺ subjects. A similar pattern was evident for erythrocyte GST activity in the GSTM1⁻ subjects. No association was found among consumption of F&V and GSTM1/T1 genotypes and plasma vitamin C level. Different consumption of F&V had no impact on plasma T-AOC and vitamin C levels in the GSTM1⁻/GSTT1⁺ or GSTM1⁻/GSTT1⁻ subjects. The erythrocyte GST activity was more sensitive to consumption of F&V in the individuals with the GSTM1⁻/GSTT1⁺ genotype. Association was found among GSTM1/T1 genotypes, antioxidant parameters and consumption of F&V. Large-scale and multiple ethnic studies are needed to further evaluate the relationship.

  6. Qualification of the nuclear reactor core model DYN3D coupled to the thermohydraulic system code ATHLET, applied as an advanced tool for accident analysis of VVER-type reactors. Final report; Qualifizierung des Kernmodells DYN3D im Komplex mit dem Stoerfallcode ATHLET als fortgeschrittenes Werkzeug fuer die Stoerfallanalyse von WWER-Reaktoren. T. 1. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Grundmann, U.; Kliem, S.; Krepper, E.; Mittag, S; Rohde, U.; Schaefer, F.; Seidel, A.

    1998-03-01

    The nuclear reactor core model DYN3D with 3D neutron kinetics has been coupled to the thermohydraulic system code ATHLET. In the report, activities on qualification of the coupled code complex ATHLET-DYN3D as a validated tool for the accident analysis of russian VVER type reactors are described. That includes: - Contributions to the validation of the single codes ATHLET and DYN3D by the analysis of experiments on natural circulation behaviour in thermohydraulic test facilities and solution of benchmark tasks on reactivity initiated transients, - the acquisition and evaluation of measurement data on transients in nuclear power plants, the validation of ATHLET-DYN3D by calculating an accident with delayed scram and a pump trip in VVER plants, - the complementary improvement of the code DYN3D by extension of the neutron physical data base, implementation of an improved coolant mixing model, consideration of decay heat release and xenon transients, - the analysis of steam leak scenarios for VVER-440 type reactors with failure of different safety systems, investigation of different model options. The analyses showed, that with realistic coolant mixing modelling in the downcomer and the lower plenum, recriticality of the scramed reactor due to overcooling can be reached. The application of the code complex ATHLET-DYN3D in Czech Republic, Bulgaria and the Ukraine has been started. Future work comprises the verification of ATHLET-DYN3D with a DYN3D version for the square fuel element geometry of western PWR. (orig.) [Deutsch] Das Reaktorkernmodell DYN3D mit 3D Neutronenkinetik wurde an den Thermohydraulik-Systemcode ATHLET angekoppelt. Im vorliegenden Bericht werden Arbeiten zur Qualifizierung des gekoppelten Codekomplexes zu einem validierten Hilfsmittel fuer Stoerfallablaufanalysen zu Reaktoren des russischen Typs WWER dargestellt. Diese umfassten im einzelnen: - Beitraege zur Validierung der Einzelcodes ATHLET und DYN3D anhand der Nachrechnung von Experimenten zum

  7. Content-based image retrieval using spatial layout information in brain tumor T1-weighted contrast-enhanced MR images.

    Directory of Open Access Journals (Sweden)

    Meiyan Huang

    Full Text Available This study aims to develop content-based image retrieval (CBIR system for the retrieval of T1-weighted contrast-enhanced MR (CE-MR images of brain tumors. When a tumor region is fed to the CBIR system as a query, the system attempts to retrieve tumors of the same pathological category. The bag-of-visual-words (BoVW model with partition learning is incorporated into the system to extract informative features for representing the image contents. Furthermore, a distance metric learning algorithm called the Rank Error-based Metric Learning (REML is proposed to reduce the semantic gap between low-level visual features and high-level semantic concepts. The effectiveness of the proposed method is evaluated on a brain T1-weighted CE-MR dataset with three types of brain tumors (i.e., meningioma, glioma, and pituitary tumor. Using the BoVW model with partition learning, the mean average precision (mAP of retrieval increases beyond 4.6% with the learned distance metrics compared with the spatial pyramid BoVW method. The distance metric learned by REML significantly outperforms three other existing distance metric learning methods in terms of mAP. The mAP of the CBIR system is as high as 91.8% using the proposed method, and the precision can reach 93.1% when the top 10 images are returned by the system. These preliminary results demonstrate that the proposed method is effective and feasible for the retrieval of brain tumors in T1-weighted CE-MR Images.

  8. Rapamycin Promotes Mouse 4T1 Tumor Metastasis that Can Be Reversed by a Dendritic Cell-Based Vaccine.

    Science.gov (United States)

    Lin, Tien-Jen; Liang, Wen-Miin; Hsiao, Pei-Wen; M S, Pradeep; Wei, Wen-Chi; Lin, Hsin-Ting; Yin, Shu-Yi; Yang, Ning-Sun

    2015-01-01

    Suppression of tumor metastasis is a key strategy for successful cancer interventions. Previous studies indicated that rapamycin (sirolimus) may promote tumor regression activity or enhance immune response against tumor targets. However, rapamycin also exhibits immunosuppressant effects and is hence used clinically as an organ transplantation drug. We hypothesized that the immunosuppressive activities of rapamycin might also negatively mediate host immunity, resulting in promotion of tumor metastasis. In this study, the effects of rapamycin and phytochemical shikonin were investigated in vitro and in vivo in a 4T1 mouse mammary tumor model through quantitative assessment of immunogenic cell death (ICD), autophagy, tumor growth and metastasis. Tumor-bearing mice were immunized with test vaccines to monitor their effect on tumor metastasis. We found that intraperitoneal (ip) administration of rapamycin after a tumor-resection surgery drastically increased the metastatic activity of 4T1 tumors. Possible correlation of this finding to human cancers was suggested by epidemiological analysis of data from Taiwan's National Health Insurance Research Database (NHIRD). Since our previous studies showed that modified tumor cell lysate (TCL)-pulsed, dendritic cell (DC)-based cancer vaccines can effectively suppress metastasis in mouse tumor models, we assessed whether such vaccines may help offset this rapamycin-promoted metastasis. We observed that shikonin efficiently induced ICD of 4T1 cells in culture, and DC vaccines pulsed with shikonin-treated TCL (SK-TCL-DC) significantly suppressed rapamycin-enhanced metastasis and Treg cell expansion in test mice. In conclusion, rapamycin treatment in mice (and perhaps in humans) promotes metastasis and the effect may be offset by treatment with a DC-based cancer vaccine.

  9. Content-based image retrieval using spatial layout information in brain tumor T1-weighted contrast-enhanced MR images.

    Science.gov (United States)

    Huang, Meiyan; Yang, Wei; Wu, Yao; Jiang, Jun; Gao, Yang; Chen, Yang; Feng, Qianjin; Chen, Wufan; Lu, Zhentai

    2014-01-01

    This study aims to develop content-based image retrieval (CBIR) system for the retrieval of T1-weighted contrast-enhanced MR (CE-MR) images of brain tumors. When a tumor region is fed to the CBIR system as a query, the system attempts to retrieve tumors of the same pathological category. The bag-of-visual-words (BoVW) model with partition learning is incorporated into the system to extract informative features for representing the image contents. Furthermore, a distance metric learning algorithm called the Rank Error-based Metric Learning (REML) is proposed to reduce the semantic gap between low-level visual features and high-level semantic concepts. The effectiveness of the proposed method is evaluated on a brain T1-weighted CE-MR dataset with three types of brain tumors (i.e., meningioma, glioma, and pituitary tumor). Using the BoVW model with partition learning, the mean average precision (mAP) of retrieval increases beyond 4.6% with the learned distance metrics compared with the spatial pyramid BoVW method. The distance metric learned by REML significantly outperforms three other existing distance metric learning methods in terms of mAP. The mAP of the CBIR system is as high as 91.8% using the proposed method, and the precision can reach 93.1% when the top 10 images are returned by the system. These preliminary results demonstrate that the proposed method is effective and feasible for the retrieval of brain tumors in T1-weighted CE-MR Images.

  10. Chronological changes in nonhaemorrhagic brain infarcts with short T1 in the cerebellum and basal ganglia

    Energy Technology Data Exchange (ETDEWEB)

    Komiyama, M.; Nakajima, H.; Nishikawa, M.; Yasui, T. [Dept. of Neurosurgery, Osaka City General Hospital, Miyakojima-Hondouri, Miyakojima, Osaka (Japan)

    2000-07-01

    Our purpose was to investigate nonhaemorrhagic infarcts with a short T1 in the cerebellum and basal ganglia. We carried out repeat MRI on 12 patients with infarcts in the cerebellum or basal ganglia with a short T1. Cerebellar cortical lesions showed high signal on T1-weighted spin-echo images beginning at 2 weeks, which became prominent from 3 weeks to 2 months, and persisted for as long as 14 months after the ictus. The basal ganglia lesions demonstrated slightly high signal from a week after the ictus, which became more intense thereafter. Signal intensity began to fade gradually after 2 months. High signal could be seen at the periphery until 5 months, and then disappeared, while low or isointense signal, seen in the central portion from day 20, persisted thereafter. (orig.)

  11. Graph C*-Algebras with a T1 Primitive Ideal Space

    DEFF Research Database (Denmark)

    Gabe, James 'Jamie'

    2013-01-01

    We give necessary and sufficient conditions which a graph should satisfy in order for its associated C∗-algebra to have a T1 primitive ideal space. We give a description of which one-point sets in such a primitive ideal space are open, and use this to prove that anypurely infinite graph C......∗-algebrapurely infinite graph C∗-algebra purely infinite graph C∗-algebra with a T1 (in particular Hausdorff) primitive ideal space, is a c0-direct sum of Kirchberg algebras. Moreover, we show that graph C∗-algebras with a T1 primitive ideal space canonically may be given the structure of a C(N ~ ) -algebra......, and that isomorphisms of their N ~ -filtered K-theory (without coefficients) lift to E(N ~ ) -equivalences, as defined by Dadarlat and Meyer...

  12. Myocardial T1 mapping: where are we now and where are we going?

    Directory of Open Access Journals (Sweden)

    Abdel-Gadir A

    2014-11-01

    Full Text Available Amna Abdel-Gadir,1,2 Thomas A Treibel,1,2 James C Moon1,2 1The Heart Hospital Imaging Centre, University College London Hospitals, London, UK; 2Institute of Cardiovascular Science, University College London, London, UK Abstract: Cardiovascular magnetic resonance offers noninvasive myocardial tissue characterization as a key unique strength over other imaging techniques. In particular T1, a tissue property that alters with disease, has gained prominence as a diagnostic tool. Prior to the administration of contrast, the native T1 changes with a number of processes such as fibrosis, edema, and infiltration. If a post-contrast scan is also acquired, the post-contrast T1 and extracellular volume fraction can be measured. Detecting and quantifying early and established myocardial pathological processes permits better diagnosis, prognostication, and tracking of therapy. Keywords: extracellular volume fraction, diffuse fibrosis, interstitium, cardiac remodeling, myocardial intracellular volume

  13. Nanoparticle-Based Systems for T1-Weighted Magnetic Resonance Imaging Contrast Agents

    Science.gov (United States)

    Zhu, Derong; Liu, Fuyao; Ma, Lina; Liu, Dianjun; Wang, Zhenxin

    2013-01-01

    Because magnetic resonance imaging (MRI) contrast agents play a vital role in diagnosing diseases, demand for new MRI contrast agents, with an enhanced sensitivity and advanced functionalities, is very high. During the past decade, various inorganic nanoparticles have been used as MRI contrast agents due to their unique properties, such as large surface area, easy surface functionalization, excellent contrasting effect, and other size-dependent properties. This review provides an overview of recent progress in the development of nanoparticle-based T1-weighted MRI contrast agents. The chemical synthesis of the nanoparticle-based contrast agents and their potential applications were discussed and summarized. In addition, the recent development in nanoparticle-based multimodal contrast agents including T1-weighted MRI/computed X-ray tomography (CT) and T1-weighted MRI/optical were also described, since nanoparticles may curtail the shortcomings of single mode contrast agents in diagnostic and clinical settings by synergistically incorporating functionality. PMID:23698781

  14. 惊艳逆袭索尼PRS-T1/PRS—G1

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    索尼于近日正式发售最新的电子书阅读器PRS-T1和PRS—G1。最大的亮点便是其独有的Cleat Touch Infrared红外触屏技术,可以在T1的电子墨水珍珠屏上实现多点触摸功能。随机还附赠一支触控笔。方便用户在阅读时进行批注。得益于索尼优秀的工业设计能力,T1的厚度保持在89mm,重量也仅为168g,是目前市面上最轻薄的6英寸电子阅读器。

  15. Comparative Analysis on Genomes from Oryza alta and Oryza latifolia by C0t-1 DNA

    Institute of Scientific and Technical Information of China (English)

    WANG De-bin; WANG Yang; WU Qi; ZHAO Hou-ming; LI Gang; QIN Rui; WANG Chun-tai; LIU Hong

    2010-01-01

    In order to reveal the origin and evolutionary relationship between two CCDD genome species, Oryza alta and Oryza latifolia, fluorescence in situ hybridization (FISH) was adopted to analyze the genomes of the two species with C0t-1 DNA from O. alta as a probe. Karyotype was also comparatively analyzed between O. alta and O. latifolia based on their similar band patterns of the hybridization signals. There were a high homology and close relationship between O. alta and O. latifolia, however, the distinction between the hybridization signals was also clear. C0t-1 DNA was proved to be species- and genome type-specific. It is suggested that C0t-1 DNA-FISH could be more efficient to analyze the genomic relationship between different species. According to the comparative analysis of highly and moderately repetitive DNA sequences between the two allotetraploidy species, O. alta and O. latifolia, the possible origin and evolutionary mechanism of allotetraploidy of Oryza were discussed.

  16. Whole brain myelin mapping using T1- and T2-weighted MR imaging data

    Directory of Open Access Journals (Sweden)

    Marco eGanzetti

    2014-09-01

    Full Text Available Despite recent advancements in MR imaging, non-invasive mapping of myelin in the brain still remains an open issue. Here we attempted to provide a potential solution. Specifically, we developed a processing workflow based on T1-w and T2-w MR data to generate an optimized myelin enhanced contrast image. The workflow allows whole brain mapping using the T1-w/T2-w technique, which was originally introduced as a non-invasive method for assessing cortical myelin content. The hallmark of our approach is a retrospective calibration algorithm, applied to bias-corrected T1-w and T2-w images, that relies on image intensities outside the brain. This permits standardizing the intensity histogram of the ratio image, thereby allowing for across-subject statistical analyses. Quantitative comparisons of image histograms within and across different datasets confirmed the effectiveness of our normalization procedure. Not only did the calibrated T1-w/T2-w images exhibit a comparable intensity range, but also the shape of the intensity histograms was largely corresponding. We also assessed the reliability and specificity of the ratio image compared to other MR-based techniques, such as magnetization transfer ratio, fractional anisotropy and fluid-attenuated inversion recovery. With respect to these other techniques, T1-w/T2-w had consistently high values, as well as low inter-subject variability, in brain structures where myelin is most abundant. Overall, our results suggested that the T1-w/T2-w technique may be a valid tool supporting the non-invasive mapping of myelin in the brain. Therefore, it might find important applications in the study of brain development, aging and disease.

  17. Diffuse myocardial fibrosis following tetralogy of Fallot repair: a T1 mapping cardiac magnetic resonance study

    Energy Technology Data Exchange (ETDEWEB)

    Kozak, Marcelo F.; Yoo, Shi-Joon; Seed, Mike; Grosse-Wortmann, Lars [The Hospital for Sick Children, University of Toronto, Labatt Family Heart Centre in the Department of Paediatrics and Department of Diagnostic Imaging, Toronto (Canada); Redington, Andrew [The Hospital for Sick Children, University of Toronto, Labatt Family Heart Centre in the Department of Paediatrics, Toronto (Canada); Greiser, Andreas [Siemens AG Healthcare Sector, Erlangen (Germany)

    2014-04-15

    Adverse ventricular remodeling after tetralogy of Fallot (TOF) repair is associated with diffuse myocardial fibrosis. The goal of this study was to measure post-contrast myocardial T1 in pediatric patients after TOF repair as surrogates of myocardial fibrosis. Children after TOF repair who underwent cardiac magnetic resonance imaging with T1 mapping using the modified look-locker inversion recovery (MOLLI) sequence were included. In addition to routine volumetric and flow data, we measured post-contrast T1 values of the basal interventricular septum, the left ventricular (LV) lateral wall, and the inferior and anterior walls of the right ventricle (RV). Results were compared to data from age-matched healthy controls. The scans of 18 children who had undergone TOF repair and 12 healthy children were included. Post-contrast T1 values of the left ventricular lateral wall (443 ± 54 vs. 510 ± 77 ms, P = 0.0168) and of the right ventricular anterior wall (333 ± 62 vs. 392 ± 72 ms, P = 0.0423) were significantly shorter in children with TOF repair than in controls, suggesting a higher degree of fibrosis. In children with TOF repair, but not in controls, post-contrast T1 values were shorter in the right ventricle than the left ventricle and shorter in the anterior wall of the right ventricle than in the inferior segments. In the TOF group, post-contrast T1 values of the RV anterior wall correlated with the RV end-systolic volume indexed to body surface area (r = 0.54; r{sup 2} = 0.30; P = 0.0238). In children who underwent tetralogy of Fallot repair the myocardium of both ventricles appears to bear an abnormally high fibrosis burden. (orig.)

  18. Ghrelin upregulates PepT1 activity in the small intestine epithelium of rats with sepsis.

    Science.gov (United States)

    Liu, Jingquan; Shi, Bin; Shi, Kai; Ma, Guoguang; Zhang, Hongze; Lou, Xiaoli; Liu, Hongxiang; Wan, Shengxia; Liang, Dongyu

    2017-02-01

    Sepsis causes nutritional substrate malabsorption; hence, preventing gut barrier problems and improving the nutritional status in sepsis is a compelling issue. We tested whether ghrelin administration affects peptide transporter 1 (PepT1) activity in the intestinal epithelium of rats with sepsis. Sixty male Sprague-Dawley rats were randomly divided into sham-operated, sepsis, and ghrelin-treated groups. The cecum of sham-operated rats was separated after laparotomy without ligation and perforation. Sepsis group rats underwent cecal ligation and puncture (CLP). Mucosal specimens were used for immunohistochemstry, real-time PCR, and western blotting to detect PepT1 distribution, and mRNA and protein expression levels, respectively. TNF-α, IL-1β, and ghrelin levels were estimated in serum and intestinal mucosal tissue by ELISA. High-performance liquid chromatography was used to measure PepT1 uptake by the epithelial cells. Moreover, survival, body weight, and food intake of the rats were recorded during the 7-day treatment period. All rats in the sham-operated group survived, and 80% of rats in the sepsis group died within 7d of CLP. Treatment with ghrelin attenuated the CLP-induced body weight loss, intestine mucosa damage, and the survival rate was better. In addition, ghrelin attenuated increases in TNF-α and IL-1β production. The expressions of PepT1 mRNA and protein were higher in ghrelin-treated group rats than in sepsis rats. Moreover, the uptake function of PepT1 was better in ghrelin-treated group rats. Ghrelin treatment can reduce the inflammatory response and greatly upregulate the physiological function of PepT1 in intestinal epithelial cells of rats with sepsis. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  19. Feasibility of abdomino-pelvic T1-weighted real-time thermal mapping of laser ablation.

    Science.gov (United States)

    Dick, Elizabeth A; Wragg, Paul; Joarder, Rita; de Jode, Michael; Lamb, Gabrielle; Gould, Stuart; Gedroyc, Wladyslaw M W

    2003-02-01

    To prove the hypothesis that T1-weighted (T1W) thermal mapping is reliable and achievable in magnetic resonance (MR)-guided laser tumor ablation. Near real-time gray and color-scale T1W thermal maps in 111 MR-guided laser thermal ablations (LTA) of liver, kidney, and uterine tumors were studied. After laser fiber placement, near real-time gray and color-scale thermal maps were produced. Previous work showed T1 signal is inversely proportional to temperature below 55 degrees C (the point of irreversible necrosis). Thermal mapping was successful in 84% of uterine, 74% of hepatic, and 20% of renal ablations. For hepatic and uterine tumors, size and conspicuity of thermal lesions were significantly greater on subtracted colorized images rather than gray-scale raw image mapping (P = 0.001, paired Student's t-test). Patient movement (N = 24), fiber charring N = 2), magnetic field distortion, and reconstruction errors (N = 2) caused mapping failure. For both renal and hepatic tumors, comparison of near real-time T1W colorized thermal map and follow up gadolinium-enhanced MR imaging revealed moderate correlation (Pearson correlation coefficient of 0.55 and 0.5, respectively). In hepatic, renal, and uterine thermal maps, the color scale produced significantly greater sized lesions with significantly greater conspicuity than the gray scale. T1W thermal mapping was reliable and successfully achieved in 73.7% of procedures, and predicted the ablated area of the tumor moderately well. Copyright 2003 Wiley-Liss, Inc.

  20. T1DBase: update 2011, organization and presentation of large-scale data sets for type 1 diabetes research.

    Science.gov (United States)

    Burren, Oliver S; Adlem, Ellen C; Achuthan, Premanand; Christensen, Mikkel; Coulson, Richard M R; Todd, John A

    2011-01-01

    T1DBase (http://www.t1dbase.org) is web platform, which supports the type 1 diabetes (T1D) community. It integrates genetic, genomic and expression data relevant to T1D research across mouse, rat and human and presents this to the user as a set of web pages and tools. This update describes the incorporation of new data sets, tools and curation efforts as well as a new website design to simplify site use. New data sets include curated summary data from four genome-wide association studies relevant to T1D, HaemAtlas-a data set and tool to query gene expression levels in haematopoietic cells and a manually curated table of human T1D susceptibility loci, incorporating genetic overlap with other related diseases. These developments will continue to support T1D research and allow easy access to large and complex T1D relevant data sets.

  1. Characterization of Benign Myocarditis Using Quantitative Delayed-Enhancement Imaging Based on Molli T1 Mapping.

    Science.gov (United States)

    Toussaint, Marcel; Gilles, Raymond J; Azzabou, Noura; Marty, Benjamin; Vignaud, Alexandre; Greiser, Andreas; Carlier, Pierre G

    2015-10-01

    Delayed contrast enhancement after injection of a gadolinium-chelate (Gd-chelate) is a reference imaging method to detect myocardial tissue changes. Its localization within the thickness of the myocardial wall allows differentiating various pathological processes such as myocardial infarction (MI), inflammatory myocarditis, and cardiomyopathies. The aim of the study was first to characterize benign myocarditis using quantitative delayed-enhancement imaging and then to investigate whether the measure of the extracellular volume fraction (ECV) can be used to discriminate between MI and myocarditis.In 6 patients with acute benign myocarditis (32.2 ± 13.8 year-old, subepicardial late gadolinium enhancement [LGE]) and 18 patients with MI (52.3 ± 10.9 year-old, subendocardial/transmural LGE), myocardial T1 was determined using the Modified Look-Locker Imaging (MOLLI) sequence at 3 Tesla before and after Gd-chelate injection. T1 values were compared in LGE and normal regions of the myocardium. The myocardial T1 values were normalized to the T1 of blood, and the ECV was calculated from T1 values of myocardium and blood pre- and post-Gd injection.In both myocarditis and MI, the T1 was lower in LGE regions than in normal regions of the left ventricle. T1 of LGE areas was significantly higher in myocarditis than in MI (446.8 ± 45.8 vs 360.5 ± 66.9 ms, P = 0.003) and ECV was lower in myocarditis than in MI (34.5 ± 3.3 vs 53.8 ± 13.0 %, P = 0.004).Both inflammatory process and chronic fibrosis induce LGE (subepicardial in myocarditis and subendocardial in MI). The present study demonstrates that the determination of T1 and ECV is able to differentiate the 2 histological patterns.Further investigation will indicate whether the severity of ECV changes might help refine the predictive risk of LGE in myocarditis.

  2. T1-nerve root neuroma presenting with apical mass and Horner's syndrome

    Directory of Open Access Journals (Sweden)

    Podnar Simon

    2007-03-01

    Full Text Available Abstract Background The appearance of dumbbell neuroma of the first thoracic root is extremely rare. The extradural component of a T1-dumbbell neuroma may present as an apical mass. The diagnosis of hand weakness is complex and may be delayed in T1-neuroma because of absence of the palpable cervical mass. One-stage removal of a T1-root neuroma and its intrathoracic extension demanded an extended posterior midline approach in the sitting position. Case presentation A 51-year old man had suffered a traumatic partial tendon rupture of his wrist flexor muscles 6 years ago. Since the incident he occasionally felt fullness and tenderness in the affected forearm with some tingling in his fingers bilaterally. During the last two years the hand weakness was continuous and hypotrophy of the medial flexor and intrinsic hand muscles had become apparent. Electrophysiological studies revealed an ulnar neuropathy in addition to mild median and radial nerve dysfunction, including a mild contralateral carpal tunnel syndrome. The diagnostic work-up for multiple mononeuropathy in the upper extremity was negative. Repeated electrophysiological studies revealed fibrillations in the C7 paravertebral muscles on the affected side. Chest x-ray revealed a large round apical mass on the affected side. A Horner's syndrome was noted at this point of diagnostic work-up. MRI of the cervical and thoracic spine revealed a dumbbell T1 neuroma enlarging the intervertebral foramen at T1-2 and a 5 cm large extradural tumor with extension into the apex of the ipsilateral lung. The patient underwent surgery in sitting position using a left dorsal midline approach. Although the T1 root could not be preserved, the patient's neurological condition was unchanged after the surgery. Conclusion Extended posterior midline exposure described here using hemilaminectomy, unilateral facetectomy and costo-transversectomy is efficient and safe for one-stage removal of dumbbell tumors at the T1

  3. The first results of electrode biasing experiments in the IR-T1 tokamak

    Energy Technology Data Exchange (ETDEWEB)

    Ghoranneviss, M; Salar Elahi, A; Mohammadi, S; Arvin, R, E-mail: salari_phy@yahoo.co [Plasma Physics Research Center, Science and Research Branch, Islamic Azad University, PO Box 14665-678, Tehran (Iran, Islamic Republic of)

    2010-09-15

    We report here the first results of our movable electrode biasing experiments performed in the IR-T1 tokamak. For this study, a movable electrode biasing system was designed, constructed and installed on the IR-T1 tokamak. A positive voltage was applied to an electrode inserted in the tokamak limiter. The plasma current, poloidal and radial components of the magnetic fields, loop voltage and diamagnetic flux in the absence and presence of the biased electrode were measured. Results of the improvement done to plasma equilibrium behaviour are compared and discussed in this paper.

  4. Prolonged T1 in patients with liver cirrhosis: an in vivo MRI study

    DEFF Research Database (Denmark)

    Thomsen, C; Christoffersen, P; Henriksen, O;

    1990-01-01

    of interest centrally located in the liver. T1 relaxation time was longer in the patients with liver cirrhosis than in the two reference groups. Ten patients had a liver biopsy taken prior to the MRI study. No correlation was found between histopathology and the measured relaxation times.......Fifteen patients with liver cirrhosis and two control groups were examined. The first control group consisted of 7 healthy volunteers, and the second group of 17 patients with nonfocal liver diseases. The T1 and T2 relaxation times were calculated from signal intensities read out from a region...

  5. T1rho MRI of menisci and cartilage in patients with osteoarthritis at 3T

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Ligong, E-mail: ligong.wang@nyumc.org [Quantitative Multinuclear Musculoskeletal Imaging Group (QMMIG), Center for Biomedical Imaging, Department of Radiology, New York University Langone Medical Center, New York, NY (United States); Chang, Gregory, E-mail: gregory.chang@nyumc.org [Quantitative Multinuclear Musculoskeletal Imaging Group (QMMIG), Center for Biomedical Imaging, Department of Radiology, New York University Langone Medical Center, New York, NY (United States); Xu, Jian, E-mail: jian.xu.sz@siemens.com [Siemens HealthCare, New York, NY (United States); Vieira, Renata L.R., E-mail: Renata.Vieira@nyumc.org [Quantitative Multinuclear Musculoskeletal Imaging Group (QMMIG), Center for Biomedical Imaging, Department of Radiology, New York University Langone Medical Center, New York, NY (United States); Krasnokutsky, Svetlana, E-mail: Svetlana.Krasnokutsky@nyumc.org [Division of Rheumatology, New York University Langone Medical Center, New York, NY (United States); Abramson, Steven, E-mail: StevenB.Abramson@nyumc.org [Division of Rheumatology, New York University Langone Medical Center, New York, NY (United States); Regatte, Ravinder R., E-mail: Ravinder.Regatte@nyumc.org [Quantitative Multinuclear Musculoskeletal Imaging Group (QMMIG), Center for Biomedical Imaging, Department of Radiology, New York University Langone Medical Center, New York, NY (United States)

    2012-09-15

    Objective: To assess and compare subregional and whole T1rho values (median ± interquartile range) of femorotibial cartilage and menisci in patients with doubtful (Kellgren–Lawrence (KL) grade 1) to severe (KL4) osteoarthritis (OA) at 3T. Materials and methods: 30 subjects with varying degrees of OA (KL1–4, 13 females, 17 males, mean age ± SD = 63.9 ± 13.1 years) were evaluated on a 3T MR scanner using a spin-lock-based 3D GRE sequence for T1rho mapping. Clinical proton density (PD)-weighted fast spin echo (FSE) images in sagittal (without fat saturation), axial, and coronal (fat-saturated) planes were acquired for cartilage and meniscus Whole-organ MR imaging score (WORMS) grading. Wilcoxon rank sum test was performed to determine whether there were any statistically significant differences between subregional and whole T1rho values of femorotibial cartilage and menisci in subjects with doubtful to severe OA. Results: Lateral (72 ± 10 ms, median ± interquartile range) and medial (65 ± 10 ms) femoral anterior cartilage subregions in moderate–severe OA subjects had significantly higher T1rho values (P < 0.05) than cartilage subregions and whole femorotibial cartilage in doubtful–minimal OA subjects. There were statistically significant differences in meniscus T1rho values of the medial posterior subregion of subjects with moderate–severe OA and T1rho values of all subregions and the whole meniscus in subjects with doubtful–minimal OA. When evaluated based on WORMS, statistically significant differences were identified in T1rho values between the lateral femoral anterior cartilage subregion in patients with WORMS5–6 (advanced degeneration) and whole femorotibial cartilage and all cartilage subregions in patients with WORMS0–1 (normal). Conclusion: T1rho values are higher in specific meniscus and femorotibial cartilage subregions. These findings suggest that regional damage of both femorotibial hyaline cartilage and menisci may be associated with

  6. Localized T1 measurements using an inversion-recovery OSIRIS method.

    Science.gov (United States)

    Girard, F; Poulet, P; Steibel, J; Chambron, J

    1993-01-01

    This work presents a new method for localized T1 measurements, based upon the OSIRIS scheme. It relies on the use of a non-selective 180 degrees pulse applied before the OSIRIS preparation cycle. The accuracy of the method has been verified with test tubes and in vivo for two nuclei, 1H and 19F. The accuracy of the T1 values is discussed, as well as possible applications of the inversion-recovery method to non-invasive in vivo pO2 measurements.

  7. SupT1 Cell Infusion as a Possible Cell-Based Therapy for HIV: Results from a Pilot Study in Hu-PBMC BRGS Mice

    Directory of Open Access Journals (Sweden)

    Jonathan Fior

    2016-04-01

    Full Text Available In a previous in vitro study, the SupT1 cell line was explored as a decoy target for HIV-1, proposing SupT1 cell infusion as a possible cell-based therapy for HIV. In the present work, the previous in vitro model was translated into an in vivo setting. Specifically, Hu-PBMC BRGS mice were infected with a high input of HIV-1 LAI (100,000 TCID50, and 40 million 30 Gy-irradiated SupT1 cells were infused weekly for 4 weeks as a therapy. Blood samples were taken to monitor CD4+ T cell count and viral load, and mice were monitored daily for signs of illness. At the earliest time point analyzed (Week 1, there was a significantly lower plasma viral load (~10-fold in all animals treated with SupT1 cell infusion, associated with a higher CD4+ T cell count. At later time points, infection proceeded with robust viral replication and evident CD4+ T cell depletion, except in one mouse that showed complete suppression of viral replication and preservation of CD4+ T cell count. No morbidity or mortality was associated with SupT1 cell infusion. The interesting tendencies observed in the generated data suggest that this approach should be further investigated as a possible cell-based HIV therapy.

  8. Accuracy, precision, and reproducibility of four T1 mapping sequences: a head-to-head comparison of MOLLI, ShMOLLI, SASHA, and SAPPHIRE.

    Science.gov (United States)

    Roujol, Sébastien; Weingärtner, Sebastian; Foppa, Murilo; Chow, Kelvin; Kawaji, Keigo; Ngo, Long H; Kellman, Peter; Manning, Warren J; Thompson, Richard B; Nezafat, Reza

    2014-09-01

    To compare accuracy, precision, and reproducibility of four commonly used myocardial T1 mapping sequences: modified Look-Locker inversion recovery (MOLLI), shortened MOLLI (ShMOLLI), saturation recovery single-shot acquisition (SASHA), and saturation pulse prepared heart rate independent inversion recovery (SAPPHIRE). This HIPAA-compliant study was approved by the institutional review board. All subjects provided written informed consent. Accuracy, precision, and reproducibility of the four T1 mapping sequences were first compared in phantom experiments. In vivo analysis was performed in seven healthy subjects (mean age ± standard deviation, 38 years ± 19; four men, three women) who were imaged twice on two separate days. In vivo reproducibility of native T1 mapping and extracellular volume (ECV) were measured. Differences between the sequences were assessed by using Kruskal-Wallis and Wilcoxon rank sum tests (phantom data) and mixed-effect models (in vivo data). T1 mapping accuracy in phantoms was lower with ShMOLLI (62 msec) and MOLLI (44 msec) than with SASHA (13 msec; P .05) and ECV quantification (∼0.01-0.02; P > .05). SASHA and SAPPHIRE yield higher accuracy, lower precision, and similar reproducibility compared with MOLLI and ShMOLLI for T1 measurement. Different sequences yield different ECV values; however, all sequences have similar reproducibility for ECV quantification.

  9. The structure of the mite allergen Blo t 1 explains the limited antibody cross-reactivity to Der p 1

    DEFF Research Database (Denmark)

    Meno, Kåre H; Kastrup, Jette S; Kuo, I-Chun

    2016-01-01

    , recombinant proBlo t 1 (rproBlo t 1), determined at 2.1 Å resolution. Overall, the fold of rproBlo t 1 is characteristic for the pro-form of cysteine proteases from the C1A class. Structural comparison of experimentally mapped Der f 1/Der p1 IgG epitopes to the same surface patch on Blo t 1, as well...

  10. Substrate Interactions during the Biodegradation of Benzene, Toluene, Ethylbenze, and Xylene (BTEX) Hydrocarbons by the Fungus Cladophialophora sp. Strain T1

    NARCIS (Netherlands)

    Prenafeta-Boldú, F.X.; Vervoort, J.; Grotenhuis, J.T.C.; Groenestijn, van J.W.

    2002-01-01

    The soil fungus Cladophialophora sp. strain T1 (= ATCC MYA-2335) was capable of growth on a model water-soluble fraction of gasoline that contained all six BTEX components (benzene, toluene, ethylbenzene, and the xylene isomers). Benzene was not metabolized, but the alkylated benzenes (toluene, ethy

  11. Substrate Interactions during the Biodegradation of Benzene, Toluene, Ethylbenze, and Xylene (BTEX) Hydrocarbons by the Fungus Cladophialophora sp. Strain T1

    NARCIS (Netherlands)

    Prenafeta-Boldú, F.X.; Vervoort, J.; Grotenhuis, J.T.C.; Groenestijn, van J.W.

    2002-01-01

    The soil fungus Cladophialophora sp. strain T1 (= ATCC MYA-2335) was capable of growth on a model water-soluble fraction of gasoline that contained all six BTEX components (benzene, toluene, ethylbenzene, and the xylene isomers). Benzene was not metabolized, but the alkylated benzenes (toluene, ethy

  12. Transcription of the rat testis-specific Rtdpoz-T1 and -T2 retrogenes during embryo development: co-transcription and frequent exonisation of transposable element sequences

    Directory of Open Access Journals (Sweden)

    Chang Che-Ming

    2009-07-01

    Full Text Available Abstract Background Retrotransposition is an important evolutionary force for the creation of new and potentially functional intronless genes which are collectively called retrogenes. Many retrogenes are expressed in the testis and the gene products have been shown to actively participate in spermatogenesis and other unique functions of the male germline. We have previously reported a cluster of retrogenes in the rat genome that encode putative TRAF- and POZ-domain proteins. Two of the genes, Rtdpoz-T1 and -T2 (abbreviated as T1 and T2, have further been shown to be expressed specifically in the rat testis. Results We show here that the T1 and T2 genes are also expressed in the rat embryo up to days 16–17 of development when the genes are silenced until being re-activated in the adult testis. On database interrogation, we find that some T1/T2 exons are chromosomally duplicated as cassettes of 2 or 3 exons consistent with retro-duplication. The embryonic T1/T2 transcripts, characterised by RT-PCR-cloning and rapid amplification of cDNA ends, are further found to have acquired one or more noncoding exons in the 5'-untranslated region (5'-UTR. Most importantly, the T1/T2 locus is embedded within a dense field of relics of transposable element (TE derived mainly from LINE1 and ERV sequences, and the TE sequences are frequently exonised through alternative splicing to form the 5'-UTR sequences of the T1/T2 transcripts. In a case of T1 transcript, the 3'-end is extended into and terminated within an L1 sequence. Since the two genes share a common exon 1 and are, therefore, regulated by a single promoter, a T2-to-T1 co-transcription model is proposed. We further demonstrate that the exonised 5'-UTR TE sequences could lead to the creation of upstream open reading frames resulting in translational repression. Conclusion Exonisation of TE sequences is a frequent event in the transcription of retrogenes during embryonic development and in the testis and

  13. Aspirin Breaks the Crosstalk between 3T3-L1 Adipocytes and 4T1 Breast Cancer Cells by Regulating Cytokine Production.

    Directory of Open Access Journals (Sweden)

    Chia-Chien Hsieh

    Full Text Available Breast cancer is one of the most common cancers in women worldwide. The obesity process is normally accompanied by chronic, low-grade inflammation. Infiltration by inflammatory cytokines and immune cells provides a favorable microenvironment for tumor growth, migration, and metastasis. Epidemiological evidence has shown that aspirin is an effective agent against several types of cancer. The aim of this study is to investigate the anti-inflammatory and anti-cancer effects of aspirin on 3T3-L1 adipocytes, 4T1 murine breast cancer cells, and their crosstalk. The results showed that aspirin treatment inhibited differentiation and lipid accumulation by 3T3-L1 preadipocytes, and decreased the secretion of the inflammatory adipokine MCP-1 after stimulation with tumor necrosis factor (TNF-α or conditioned medium from RAW264.7 cells. In 4T1 cells, treatment with aspirin decreased cell viability and migration, possibly by suppressing MCP-1 and VEGF secretion. Subsequently, culture of 4T1 cells in 3T3-L1 adipocyte-conditioned medium (Ad-CM and co-culture of 3T3-L1 and 4T1 cells using a transwell plate were performed to clarify the relationship between these two cell lines. Aspirin exerted its inhibitory effects in the transwell co-culture system, as well as the conditioned-medium model. Aspirin treatment significantly inhibited the proliferation of 4T1 cells, and decreased the production of MCP-1 and PAI-1 in both the Ad-CM model and co-culture system. Aspirin inhibited inflammatory MCP-1 adipokine production by 3T3-L1 adipocytes and the cell growth and migration of 4T1 cells. It also broke the crosstalk between these two cell lines, possibly contributing to its chemopreventive properties in breast cancer. This is the first report that aspirin's chemopreventive activity supports the potential application in auxiliary therapy against obesity-related breast cancer development.

  14. Aspirin Breaks the Crosstalk between 3T3-L1 Adipocytes and 4T1 Breast Cancer Cells by Regulating Cytokine Production.

    Science.gov (United States)

    Hsieh, Chia-Chien; Huang, Yu-Shan

    2016-01-01

    Breast cancer is one of the most common cancers in women worldwide. The obesity process is normally accompanied by chronic, low-grade inflammation. Infiltration by inflammatory cytokines and immune cells provides a favorable microenvironment for tumor growth, migration, and metastasis. Epidemiological evidence has shown that aspirin is an effective agent against several types of cancer. The aim of this study is to investigate the anti-inflammatory and anti-cancer effects of aspirin on 3T3-L1 adipocytes, 4T1 murine breast cancer cells, and their crosstalk. The results showed that aspirin treatment inhibited differentiation and lipid accumulation by 3T3-L1 preadipocytes, and decreased the secretion of the inflammatory adipokine MCP-1 after stimulation with tumor necrosis factor (TNF)-α or conditioned medium from RAW264.7 cells. In 4T1 cells, treatment with aspirin decreased cell viability and migration, possibly by suppressing MCP-1 and VEGF secretion. Subsequently, culture of 4T1 cells in 3T3-L1 adipocyte-conditioned medium (Ad-CM) and co-culture of 3T3-L1 and 4T1 cells using a transwell plate were performed to clarify the relationship between these two cell lines. Aspirin exerted its inhibitory effects in the transwell co-culture system, as well as the conditioned-medium model. Aspirin treatment significantly inhibited the proliferation of 4T1 cells, and decreased the production of MCP-1 and PAI-1 in both the Ad-CM model and co-culture system. Aspirin inhibited inflammatory MCP-1 adipokine production by 3T3-L1 adipocytes and the cell growth and migration of 4T1 cells. It also broke the crosstalk between these two cell lines, possibly contributing to its chemopreventive properties in breast cancer. This is the first report that aspirin's chemopreventive activity supports the potential application in auxiliary therapy against obesity-related breast cancer development.

  15. Methionine Regulates mTORC1 via the T1R1/T1R3-PLCβ-Ca2+-ERK1/2 Signal Transduction Process in C2C12 Cells

    Directory of Open Access Journals (Sweden)

    Yuanfei Zhou

    2016-10-01

    Full Text Available The mammalian target of rapamycin complex 1 (mTORC1 integrates amino acid (AA availability to support protein synthesis and cell growth. Taste receptor type 1 member (T1R is a G protein-coupled receptor that functions as a direct sensor of extracellular AA availability to regulate mTORC1 through Ca2+ stimulation and extracellular signal–regulated kinases 1 and 2 (ERK1/2 activation. However, the roles of specific AAs in T1R1/T1R3-regulated mTORC1 are poorly defined. In this study, T1R1 and T1R3 subunits were expressed in C2C12 myotubes, and l-AA sensing was accomplished by T1R1/T1R3 to activate mTORC1. In response to l-AAs, such as serine (Ser, arginine (Arg, threonine (Thr, alanine (Ala, methionine (Met, glutamine (Gln, and glycine (Gly, Met induced mTORC1 activation and promoted protein synthesis. Met also regulated mTORC1 via T1R1/T1R3-PLCβ-Ca2+-ERK1/2 signal transduction. Results revealed a new role for Met-regulated mTORC1 via an AA receptor. Further studies should be performed to determine the role of T1R1/T1R3 in mediating extracellular AA to regulate mTOR signaling and to reveal its mechanism.

  16. Methionine Regulates mTORC1 via the T1R1/T1R3-PLCβ-Ca2+-ERK1/2 Signal Transduction Process in C2C12 Cells

    Science.gov (United States)

    Zhou, Yuanfei; Ren, Jiao; Song, Tongxing; Peng, Jian; Wei, Hongkui

    2016-01-01

    The mammalian target of rapamycin complex 1 (mTORC1) integrates amino acid (AA) availability to support protein synthesis and cell growth. Taste receptor type 1 member (T1R) is a G protein-coupled receptor that functions as a direct sensor of extracellular AA availability to regulate mTORC1 through Ca2+ stimulation and extracellular signal–regulated kinases 1 and 2 (ERK1/2) activation. However, the roles of specific AAs in T1R1/T1R3-regulated mTORC1 are poorly defined. In this study, T1R1 and T1R3 subunits were expressed in C2C12 myotubes, and l-AA sensing was accomplished by T1R1/T1R3 to activate mTORC1. In response to l-AAs, such as serine (Ser), arginine (Arg), threonine (Thr), alanine (Ala), methionine (Met), glutamine (Gln), and glycine (Gly), Met induced mTORC1 activation and promoted protein synthesis. Met also regulated mTORC1 via T1R1/T1R3-PLCβ-Ca2+-ERK1/2 signal transduction. Results revealed a new role for Met-regulated mTORC1 via an AA receptor. Further studies should be performed to determine the role of T1R1/T1R3 in mediating extracellular AA to regulate mTOR signaling and to reveal its mechanism. PMID:27727170

  17. Extract of Azadirachta indica (Neem) Leaf Induces Apoptosis in 4T1 Breast Cancer BALB/c Mice.

    Science.gov (United States)

    Othman, Fauziah; Motalleb, Gholamreza; Lam Tsuey Peng, Sally; Rahmat, Asmah; Fakurazi, Sharida; Pei Pei, Chong

    2011-01-01

    Azadirachta indica (Neem) has been used traditionally for many centuries. Some impressive therapeutic qualities have been discovered. However, the therapeutic effect of neem leaf extract in 4T1 breast cancer has not been documented. The purpose of the present study is to investigate the therapeutic effect of ethanolic Neem leaf extract in an in vivo 4T1 breast cancer model in mice. A total of 84 female BALB/c mice were divided randomly into 7 groups (3 non-cancerous groups and 4 cancerous groups) consisting of 12 mice per group. The 3 non-cancerous groups were normal mice treated with 0.5% of Tween 20 in phosphate buffer saline (PBS) (NC), 250 mg/kg Neem (N250) or 500 mg/kg Neem (N500). The 4 cancerous groups were; cancer controls treated with 0.5% of Tween 20 in PBS (CC), and cancerous mice treated with 0.5 µg/mL tamoxifen citrate (CT), 250 mg/kg Neem leaf extract (CN 250) or 500 mg/kg Neem leaf extract (CN 500). Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assays were used to evaluate apoptosis (cell death) in the breast cancer tissues. SPSS software, version 14 was used for statistical analysis. Statistical significance was defined as p≤0.05. Non parametric analysis of variance (ANOVA) was performed with the Kruskal Wallis test for the TUNEL assays. Parametric data among the groups was compared using ANOVA. TUNEL assays showed that the CN 250 and CN 500 groups had a higher incidence of apoptosis compared with the cancer controls. The findings showed that neem leaf extract induces apoptosis in 4T1 breast cancer BALB/c mice.

  18. Simultaneous investigation of the T =1 (Jπ=0+) and T =0 (Jπ=9+) β decays in 70Br

    Science.gov (United States)

    Morales, A. I.; Algora, A.; Rubio, B.; Kaneko, K.; Nishimura, S.; Aguilera, P.; Orrigo, S. E. A.; Molina, F.; de Angelis, G.; Recchia, F.; Kiss, G.; Phong, V. H.; Wu, J.; Nishimura, D.; Oikawa, H.; Goigoux, T.; Giovinazzo, J.; Ascher, P.; Agramunt, J.; Ahn, D. S.; Baba, H.; Blank, B.; Borcea, C.; Boso, A.; Davies, P.; Diel, F.; Dombrádi, Zs.; Doornenbal, P.; Eberth, J.; de France, G.; Fujita, Y.; Fukuda, N.; Ganioglu, E.; Gelletly, W.; Gerbaux, M.; Grévy, S.; Guadilla, V.; Inabe, N.; Isobe, T.; Kojouharov, I.; Korten, W.; Kubo, T.; Kubono, S.; Kurtukián Nieto, T.; Kurz, N.; Lee, J.; Lenzi, S.; Liu, J.; Lokotko, T.; Lubos, D.; Magron, C.; Montaner-Pizá, A.; Napoli, D. R.; Sakurai, H.; Schaffner, H.; Shimizu, Y.; Sidong, C.; Söderström, P.-A.; Sumikama, T.; Suzuki, H.; Takeda, H.; Takei, Y.; Tanaka, M.; Yagi, S.

    2017-06-01

    The β decay of the odd-odd nucleus 70Br has been investigated with the BigRIPS and EURICA setups at the Radioactive Ion Beam Factory (RIBF) of the RIKEN Nishina Center. The T =0 (Jπ=9+ ) and T =1 (Jπ=0+ ) isomers have both been produced in in-flight fragmentation of 78Kr with ratios of 41.6(8)% and 58.4(8)%, respectively. A half-life of t1 /2=2157-49+53 ms has been measured for the Jπ=9+ isomer from γ -ray time decay analysis. Based on this result, we provide a new value of the half-life for the Jπ=0+ ground state of 70Br,t1 /2=78.42 ±0.51 ms, which is slightly more precise, and in excellent agreement, with the best measurement reported hitherto in the literature. For this decay, we provide the first estimate of the total branching fraction decaying through the 21+ state in the daughter nucleus 70Se,R (21+)=1.3 ±1.1 % . We also report four new low-intensity γ -ray transitions at 661, 1103, 1561, and 1749 keV following the β decay of the Jπ=9+ isomer. Based on their coincidence relationships, we tentatively propose two new excited states at 3945 and 4752 keV in 70Se with most probable spins and parities of Jπ=(6+) and (8+) , respectively. The observed structure is interpreted with the help of shell-model calculations, which predict a complex interplay between oblate and prolate configurations at low excitation energies.

  19. Extract of Azadirachta indica (Neem Leaf Induces Apoptosis in 4T1 Breast Cancer BALB/c Mice

    Directory of Open Access Journals (Sweden)

    Fauziah Othman

    2011-01-01

    Full Text Available Objective: Azadirachta indica (Neem has been used traditionally for many centuries.Some impressive therapeutic qualities have been discovered. However, the therapeuticeffect of neem leaf extract in 4T1 breast cancer has not been documented. The purposeof the present study is to investigate the therapeutic effect of ethanolic Neem leaf extractin an in vivo 4T1 breast cancer model in mice.Materials and Methods: A total of 84 female BALB/c mice were divided randomly into7 groups (3 non-cancerous groups and 4 cancerous groups consisting of 12 mice pergroup. The 3 non-cancerous groups were normal mice treated with 0.5% of Tween 20 inphosphate buffer saline (PBS (NC, 250 mg/kg Neem (N250 or 500 mg/kg Neem (N500.The 4 cancerous groups were; cancer controls treated with 0.5% of Tween 20 in PBS(CC, and cancerous mice treated with 0.5 μg/mL tamoxifen citrate (CT, 250 mg/kg Neemleaf extract (CN 250 or 500 mg/kg Neem leaf extract (CN 500. Terminal deoxynucleotidyltransferase dUTP nick end labeling (TUNEL assays were used to evaluate apoptosis(cell death in the breast cancer tissues. SPSS software, version 14 was used for statisticalanalysis. Statistical significance was defined as p<0.05. Non parametric analysis ofvariance (ANOVA was performed with the Kruskal Wallis test for the TUNEL assays.Parametric data among the groups was compared using ANOVA.Results: TUNEL assays showed that the CN 250 and CN 500 groups had a higher incidenceof apoptosis compared with the cancer controls.Conclusion: The findings showed that neem leaf extract induces apoptosis in 4T1 breastcancer BALB/c mice.

  20. pH dependence of the urea and guanidine hydrochloride denaturation of ribonuclease A and ribonuclease T1.

    Science.gov (United States)

    Pace, C N; Laurents, D V; Thomson, J A

    1990-03-13

    To investigate the pH dependence of the conformational stability of ribonucleases A and T1, urea and guanidine hydrochloride denaturation curves have been determined over the pH range 2-10. The maximum conformational stability of both proteins is about 9 kcal/mol and occurs near pH 4.5 for ribonuclease T1 and between pH 7 and 9 for ribonuclease A. The pH dependence suggests that electrostatic interactions among the charged groups make a relatively small contribution to the conformational stability of these proteins. The dependence of delta G on urea concentration increases from about 1200 cal mol-1 M-1 at high pH to about 2400 cal mol-1 M-1 at low pH for ribonuclease A. This suggests that the unfolded conformations of RNase A become more accessible to urea as the net charge on the molecule increases. For RNase T1, the dependence of delta G on urea concentration is minimal near pH 6 and increases at both higher and lower pH. An analysis of information of this type for several proteins in terms of a model developed by Tanford [Tanford, C. (1964) J. Am. Chem. Soc. 86, 2050-2059] suggests that the unfolded states of proteins in urea and GdnHCl solutions may differ significantly in the extent of their interaction with denaturants. Thus, the conformations assumed by unfolded proteins may depend to at least some extent on the amino acid sequence of the protein.

  1. Changes of biological functions of dipeptide transporter (PepT1)and hormonal regulation in severe scald rats

    Institute of Scientific and Technical Information of China (English)

    Bing-Wei Sun; Xiao-Chen Zhao; Guang-Ji Wang; Ning Li; Jie-Shou Li

    2003-01-01

    AIM: To determine the regulatory effects of recombinant human growth hormone (rhGH) on dipeptide transport (PepT1) in normal and severe scald rats.METHODS: Male Sprague-Dawley rats with 30 % total body surface area (TBSA) Ⅲ degree scald were employed as the model. In this study rhGH was used at the dose of 2 IU.kg-1d-1. An everted sleeve of intestine 4 cm long obtained from mid-jejunum was securely incubated in Kreb's solution with radioactive dipeptide (3H-glycylsarcosine, 3H-Gly-Sar,10 μCi/ml) at 37 ℃ for 15 min to measure the effects of uptake and transport of PepT1 of small intestinal epithelial cells in normal and severe scald rats.RESULTS: Abundant blood supply to intestine and mesentery was observed in normal and scald rats administered rhGH,while less supply of blood to intestine and mesentery was observed in rats without rhGH. Compared with controls, the transport of dipeptide in normal rats with injection of rhGH was not significantly increased (P=0.1926), while the uptake was significantly increased (P=0.0253). The effects of transport and uptake of PepT1 in scald rats with injection of rhGH were significantly increased (P=0.0082, 0.0391).CONCLUSION: Blood supply to intestine and mesentery of rats was increased following injection of rhGH. The effects of uptake and transport of dipeptide transporters in small intestinal epithelial cells of rats with severe scald were markedly up-regulated by rhGH.

  2. Effect of berberine on Cdk9 and cyclin T1 expressions in myocardium of diabetic rats

    Institute of Scientific and Technical Information of China (English)

    Zhou Jiyin; Zhou Shiwen; Tang Jianlin; Xu Ying; Ying Yi

    2008-01-01

    Objective: To investigate the effect of berberine, one of the main alkaloids of Rhizoma coptidis, on myocardial orphology and the expressions of cyclin-dependent kinase 9 (Cdk9) and cyclin T1 protein in the myocardium of type diabetic rats. Methods: Type 2 diabetes mellitus rats were induced by an injection of 35 mg/kg streptozotocin (STZ) nd a high-carbohydrate/high-fat diet for 16 weeks. Diabetic rats were given low-, middle-, high-dose berberine (75,150, 300 mg/kg), fenofibrate (100 mg/kg) and rosiglitazone (4 mg/kg) for another 16 weeks, respectively. The myocardium structure was observed with hematoxylin & eosin (H&E) staining and Cdk9 and cyclin T1 protein expressions were detected by immunohistochemistry. Results: Middle-dose, high-dose berberine improved myocardial hypertrophy and interstitial fibrosis of diabetic rats. Cdk9 and cyclin T1 protein were significantly lower in diabetic myocardium than in control one (P<0.01), and middle-dose, high-dose berberine and fenofibrate obviously increased oth Cdk9 and cyclin T1 expression to near control level (P<0.01). Conclusion: Berberine modulates Cdk9 and cyclin I protein expression in diabetic myocardium which may contribute to ameliorate myocardium damage.

  3. T1a glottic cancers may be removed by "cold steel" excision biopsies

    DEFF Research Database (Denmark)

    Melchiors, Jacob; Tvedskov, Jesper; Kristensen, Claus Andrup

    2013-01-01

    Phonosurgical excision biopsies are gradually replacing traditional punch biopsies during direct lar-yngoscopy. As excision aims at removing all pathologic tissue, some malignant lesions may be completely removed. We present our experience with phonosurgical excision biopsies of T1a glottic cance...

  4. Non-small cell lung cancer: the new T1 categories

    Science.gov (United States)

    Van Schil, Paul E.

    2017-01-01

    Recently, major changes have occurred in the staging, diagnosis, and treatment of early stage lung cancer. By screening high-risk populations, we are now able to detect lung cancers at an early stage, but the false-positive rate is high. A new pathological classification was published in 2011 and fully incorporated in the 2015 World Health Organisation (WHO) Classification of Tumours of the Lung, Pleura, Thymus, and Heart. The new eighth edition of the tumour–node–metastasis (TNM) staging system has been fully published and will be in use from January 2017. T1 lesions are subdivided into T1a, T1b, and T1c lesions corresponding to lung cancers up to 10 mm, between 11 and 20 mm, and between 21 and 30 mm, respectively. To determine the size, only the solid part on computed tomographic scanning of the chest and the invasive part on pathological examination will be considered. Prognosis is significantly better for the smallest lesions. For some specific subgroups, sublobar resection may be oncologically valid and yield good long-term outcome, but the results of recently performed randomised trials are awaited. PMID:28299198

  5. Prolonged T1 relaxation of the hemopoietic bone marrow in patients with chronic leukemia

    DEFF Research Database (Denmark)

    Jensen, K E; Sørensen, P G; Thomsen, C

    1990-01-01

    Eleven patients with chronic leukemia (7 with chronic lymphocytic leukemia and 4 with chronic myeloid leukemia) were evaluated with magnetic resonance (MR) imaging and T1 relaxation time measurements by use of a 1.5 tesla whole body MR scanner. Bone marrow biopsies were obtained from the posterior...

  6. Survival after primary and deferred cystectomy for stage T1 transitional cell carcinoma of the bladder

    Directory of Open Access Journals (Sweden)

    Bedeir Ali-El-Dein

    2011-01-01

    Conclusions: Cancer-specific survival is statistically comparable for primary and deferred cystectomy in T1 bladder cancer, although there is a non-significant difference in favor of primary cystectomy. In the deferred cystectomy group, the number of TURBTs beyond three is associated with lower survival. Conservative treatment should be adopted for most cases in this category.

  7. Characterizing diabetes burnout in parents of youth with type 1 diabetes (T1D)

    Science.gov (United States)

    Managing type 1 diabetes (T1D) is complex and requires round-the-clock attention, much of which falls to parents. Parental stress and family conflict about diabetes are associated with suboptimal youth self-management and glycemic outcomes, yet little research has described parents' experiences with...

  8. Measurement of brain oxygenation changes using dynamic T1-weighted imaging

    DEFF Research Database (Denmark)

    Haddock, Bryan; Larsson, Henrik B W; Hansen, Adam E

    2013-01-01

    Magnetic resonance imaging (MRI) has proven useful in evaluating oxygenation in several types of tissue and blood. This study evaluates brain tissue oxygenation changes between normoxia and hyperoxia in healthy subjects using dynamic T1 and T2*-weighted imaging sequences. The change in FiO2 induced...... in the brain with a potential to provide quantitative information on tissue oxygenation....

  9. MyT1 Counteracts the Neural Progenitor Program to Promote Vertebrate Neurogenesis

    Directory of Open Access Journals (Sweden)

    Francisca F. Vasconcelos

    2016-10-01

    Full Text Available The generation of neurons from neural stem cells requires large-scale changes in gene expression that are controlled to a large extent by proneural transcription factors, such as Ascl1. While recent studies have characterized the differentiation genes activated by proneural factors, less is known on the mechanisms that suppress progenitor cell identity. Here, we show that Ascl1 induces the transcription factor MyT1 while promoting neuronal differentiation. We combined functional studies of MyT1 during neurogenesis with the characterization of its transcriptional program. MyT1 binding is associated with repression of gene transcription in neural progenitor cells. It promotes neuronal differentiation by counteracting the inhibitory activity of Notch signaling at multiple levels, targeting the Notch1 receptor and many of its downstream targets. These include regulators of the neural progenitor program, such as Hes1, Sox2, Id3, and Olig1. Thus, Ascl1 suppresses Notch signaling cell-autonomously via MyT1, coupling neuronal differentiation with repression of the progenitor fate.

  10. A new carotenoid glycosyl ester isolated from a marine microorganism, Fusarium strain T-1.

    Science.gov (United States)

    Sakaki, Hideyuki; Kaneno, Hirokazu; Sumiya, Yasuji; Tsushima, Miyuki; Miki, Wataru; Kishimoto, Noriaki; Fujita, Tokio; Matsumoto, Sadayoshi; Komemushi, Sadao; Sawabe, Akiyoshi

    2002-11-01

    A new carotenoid glycosyl ester, neurosporaxanthin beta-D-glucopyranoside (2), together with neurosporaxanthin (1), beta-carotene, gamma-carotene, and torulene were isolated from cultured cells of a marine microorganism, strain T-1, which was identified as Fusarium sp. Their structures were determined by chemical and spectral data.

  11. Functional imaging with MR T1 contrast: a feasibility study with blood-pool contrast agent

    Energy Technology Data Exchange (ETDEWEB)

    Majos, Agata; Stefanczyk, Ludomir [Medical University of Lodz, Radiology Department, Lodz (Poland); Bogorodzki, Piotr; Piatkowska-Janko, Ewa; Kurjata, Robert [Warsaw University of Technology, Institute of Radioelectronics, Warsaw (Poland); Wolak, Tomasz [Institute of Physiology and Pathology of Hearing, Warsaw (Poland)

    2009-04-15

    The aim of this study was to prove the concept of using a long intravenous half-life blood-pool T1 contrast agent as a new functional imaging method. For each of ten healthy subjects, two dynamic magnetic resonance (MR) protocols were carried out: (1) a reference run with a typical T2* echo-planar imaging (EPI) sequence based on the blood oxygenation level-dependent (BOLD) effect and (2) a run with a T1-sensitive three-dimensional (3D) gradient-echo (GRE) sequence using cerebral blood volume (CBV) contrast after intravenous administration of a contrast agent containing a chelate of gadolinium diethylene-triamine-pentaacetate with a phosphono-oxymethyl substituent. All sequences were performed during the execution of a block-type finger-tapping paradigm. SPM5 software was used for statistical analysis. For both runs maximum activations (peak Z-score = 5.5, cluster size 3,449 voxels) were localized in the left postcentral gyrus. Visual inspection of respective signal amplitudes suggests the T1 contrast to be substantially smaller than EPI (0.5% vs 1%). A new functional imaging method with potentially smaller image artefacts due to the nature of CBV contrast and characteristics of the T1 sequence was proposed and verified. (orig.)

  12. Association of MRI T1 relaxation time with neuropsychological test performance in manganese- exposed welders.

    Science.gov (United States)

    Bowler, R M; Yeh, C-L; Adams, S W; Ward, E J; Ma, R E; Dharmadhikari, S; Snyder, S A; Zauber, S E; Wright, C W; Dydak, U

    2017-06-03

    This study examines the results of neuropsychological testing of 26 active welders and 17 similar controls and their relationship to welders' shortened MRI T1 relaxation time, indicative of increased brain manganese (Mn) accumulation. Welders were exposed to Mn for an average duration of 12.25 years to average levels of Mn in air of 0.11±0.05mg/m(3). Welders scored significantly worse than controls on Fruit Naming and the Parallel Lines test of graphomotor tremor. Welders had shorter MRI T1 relaxation times than controls in the globus pallidus, substantia nigra, caudate nucleus, and the anterior prefrontal lobe. 63% of the variation in MRI T1 relaxation times was accounted for by exposure group. In welders, lower relaxation times in the caudate nucleus and substantia nigra were associated with lower neuropsychological test performance on tests of verbal fluency (Fruit Naming), verbal learning, memory, and perseveration (WHO-UCLA AVLT). Results indicate that verbal function may be one of the first cognitive domains affected by brain Mn deposition in welders as reflected by MRI T1 relaxation times. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. Fratura traumática de coluna torácica T1-T10 Traumatic fracture of the thoracic spine T1-T10

    Directory of Open Access Journals (Sweden)

    Asdrubal Falavigna

    2004-12-01

    Full Text Available Descrevemos a incidência, causas, manejo e prognóstico das fraturas traumáticas de coluna torácica de T1 a T10. Estudamos retrospectivamente os casos cirúrgicos de fraturas traumáticas da coluna torácica (T1 a T10, durante o período de junho de 1994 a junho de 2003. O tipo de fratura foi determinado segundo a classificação de Gertzbein e o grau de estabilidade através da classificação de Denis. O quadro neurológico à internação e 30 dias após a cirurgia foi avaliado através da classificação de ASIA/IMSOP. O objetivo da cirurgia nos pacientes com lesão medular completa (n=7 foi de estabilização, enquanto nos casos de instabilidade vertebral em que não houve lesão medular ou esta foi incompleta (n=12, optou-se pela descompressão do tecido nervoso, correção do alinhamento da coluna e estabilização da coluna.We describe the incidence, causes, management and prognosis of traumatic fractures of the thoracic spine from T1 to T10 in surgical cases of traumatic fractures of spine during the period from June 1994 to June 2003 studied retrospectively. The type of fracture was determined according to the Gertzbein classification, and the degree of stability using the Denis classification. The neurological picture at admission and 30 days after surgery was evaluated using the ASIA/IMSOP classification. Surgery was performed in patients with complete spinal cord injury (n=7 for the purpose of stabilization using the posterior approach. In cases without spinal cord injury or incomplete injury (n=12, the surgical procedure was performed aiming to decompress the nerve tissue, to correct the alignment of the spine and to stabilize the spine.

  14. Chemical design of nanoprobes for T1-weighted magnetic resonance imaging

    Directory of Open Access Journals (Sweden)

    Yung-Kang Peng

    2016-07-01

    Full Text Available Magnetic resonance imaging (MRI, which offers a number of advantages such as unlimited tissue penetration, zero ionizing radiation, and a noninvasive nature, has received considerable attention over the past two decades as a technique for clinical diagnosis. To improve imaging sensitivity, contrast agents have been employed to accelerate the relaxation rate of water molecules and thus to increase the contrast between specific tissues or organs of interest. However, conventional contrast agents such as Gd3+-based T1 complexes and iron oxide nanoparticle-based T2 contrast agents have been proven to have adverse effects. The former may cause fatal nephrogenic systemic fibrosis (NSF and difficulty in metabolism, while the latter is less sensitive due to the background interference. Also, their development has been well documented. Therefore, the orientation of this review will be geared toward the newly developed nanoparticulate agents that serve as better alternatives. In this regard, the recent advances on various nanostructured Mn/Fe-based T1 contrast agents seem to fit these categories. As they reveal longer circulation half-life and better biocompatibility, they have demonstrated themselves as a promising T1 candidate for MRI. The focus of this review will be on the preparation and fabrication of T1 contrast agents that contain mainly paramagnetic manganese and iron ions, with special attention being paid to the growth mechanism. Additional emphasis is also put on their progressive development in an aim to overcome the drawbacks of classical iron oxide nanoparticle-based T2 and Gd3+-based T1 contrast agents. Representative applications in vitro and in vivo will be presented for this new generation of contrast agents. The pros and cons of each case are also briefly summarized.

  15. GEOID '88: A gravimetric geoid for Canada

    Science.gov (United States)

    Nagy, Dezso

    1989-01-01

    Using Stokes' formula, a gravimetric geoid was calculated for Canada. The input data are as follows: 15 x 15' block averages were used for Canada and the USA and 1 x 1 deg block averages and satellite model (GEM-T1) provided values for the remaining part of the Earth. The geoid was calculated at 6398 points covering the area within the points rho(sub i)(phi sub i; lambda sub i) (lambda is + west): rho sub 1(40,125); rho sub 2(75,184); rho sub 3(75,10); and rho sub 4(40,60). The computed geoid refers to the GRS1980 and reaches a local minimum of -47.3 meters around the western part of Hudson Bay. A contour map of the geoid is shown.

  16. Differential Regulation of ERK1/2 and mTORC1 Through T1R1/T1R3 in MIN6 Cells.

    Science.gov (United States)

    Wauson, Eric M; Guerra, Marcy L; Dyachok, Julia; McGlynn, Kathleen; Giles, Jennifer; Ross, Elliott M; Cobb, Melanie H

    2015-08-01

    The MAPKs ERK1/2 respond to nutrients and other insulin secretagogues in pancreatic β-cells and mediate nutrient-dependent insulin gene transcription. Nutrients also stimulate the mechanistic target of rapamycin complex 1 (mTORC1) to regulate protein synthesis. We showed previously that activation of both ERK1/2 and mTORC1 in the MIN6 pancreatic β-cell-derived line by extracellular amino acids (AAs) is at least in part mediated by the heterodimeric T1R1/T1R3, a G protein-coupled receptor. We show here that AAs differentially activate these two signaling pathways in MIN6 cells. Pretreatment with pertussis toxin did not prevent the activation of either ERK1/2 or mTORC1 by AAs, indicating that G(I) is not central to either pathway. Although glucagon-like peptide 1, an agonist for a G(s-)coupled receptor, activated ERK1/2 well and mTORC1 to a small extent, AAs had no effect on cytosolic cAMP accumulation. Ca(2+) entry is required for ERK1/2 activation by AAs but is dispensable for AA activation of mTORC1. Pretreatment with UBO-QIC, a selective G(q) inhibitor, reduced the activation of ERK1/2 but had little effect on the activation of mTORC1 by AAs, suggesting a differential requirement for G(q). Inhibition of G(12/13) by the overexpression of the regulator of G protein signaling domain of p115 ρ-guanine nucleotide exchange factor had no effect on mTORC1 activation by AAs, suggesting that these G proteins are also not involved. We conclude that AAs regulate ERK1/2 and mTORC1 through distinct signaling pathways.

  17. Initial evaluation of hepatic T1 relaxation time as an imaging marker of liver disease associated with autosomal recessive polycystic kidney disease (ARPKD).

    Science.gov (United States)

    Gao, Ying; Erokwu, Bernadette O; DeSantis, David A; Croniger, Colleen M; Schur, Rebecca M; Lu, Lan; Mariappuram, Jose; Dell, Katherine M; Flask, Chris A

    2016-01-01

    Autosomal recessive polycystic kidney disease (ARPKD) is a potentially lethal multi-organ disease affecting both the kidneys and the liver. Unfortunately, there are currently no non-invasive methods to monitor liver disease progression in ARPKD patients, limiting the study of potential therapeutic interventions. Herein, we perform an initial investigation of T1 relaxation time as a potential imaging biomarker to quantitatively assess the two primary pathologic hallmarks of ARPKD liver disease: biliary dilatation and periportal fibrosis in the PCK rat model of ARPKD. T1 relaxation time results were obtained for five PCK rats at 3 months of age using a Look-Locker acquisition on a Bruker BioSpec 7.0 T MRI scanner. Six three-month-old Sprague-Dawley (SD) rats were also scanned as controls. All animals were euthanized after the three-month scans for histological and biochemical assessments of bile duct dilatation and hepatic fibrosis for comparison. PCK rats exhibited significantly increased liver T1 values (mean ± standard deviation = 935 ± 39 ms) compared with age-matched SD control rats (847 ± 26 ms, p = 0.01). One PCK rat exhibited severe cholangitis (mean T1  = 1413 ms), which occurs periodically in ARPKD patients. The observed increase in the in vivo liver T1 relaxation time correlated significantly with three histological and biochemical indicators of biliary dilatation and fibrosis: bile duct area percent (R = 0.85, p = 0.002), periportal fibrosis area percent (R = 0.82, p = 0.004), and hydroxyproline content (R = 0.76, p = 0.01). These results suggest that hepatic T1 relaxation time may provide a sensitive and non-invasive imaging biomarker to monitor ARPKD liver disease.

  18. Interobserver and test-retest reproducibility of T1ρ and T2 mesurements of lumber intervertebral discs by 3t magnetic resonance imaging

    Energy Technology Data Exchange (ETDEWEB)

    Yoo, Yeon Hwa; Yoon, Choon Sik; Eun, Na Lae; Kim, Sung Jin; Chung, Tae Sub [Dept. of Radiology, Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul (Korea, Republic of); Hwang, Moon Jung [GE Health Care, Seoul (Korea, Republic of); Yoo, Hanna [Biostatistics Collaboration Lab, Yonsei University College of Medicine, Seoul (Korea, Republic of); Peter, Robert D. [GE Health Care, Milwaukee (United States); Lee, Young Han; Suh, Jin Suck [Dept. of Radiology, Severance Hospital, Yonsei University College of Medicine, Seoul (Korea, Republic of)

    2016-11-15

    To investigate the interobserver and test-retest reproducibility of T1ρ and T2 measurements of lumbar intervertebral discs using 3T magnetic resonance imaging (MRI). This study included a total of 51 volunteers (female, 26; male, 25; mean age, 54 ± 16.3 years) who underwent lumbar spine MRI with a 3.0 T scanner. Amongst these subjects, 40 underwent repeat T1ρ and T2 measurement acquisitions with identical image protocol. Two observers independently performed the region of interest measurements in the nuclei pulposi of the discs from L1-2 through L5-S1 levels. Statistical analysis was performed using intraclass correlation coefficient (ICC) with a two-way random model of absolute agreement. Comparison of the ICC values was done after acquisition of ICC values using Z test. Statistical significance was defined as p value < 0.05. The ICCs of interobserver reproducibility were 0.951 and 0.672 for T1ρ and T2 mapping, respectively. The ICCs of test-retest reproducibility (40 subjects) for T1ρ and T2 measurements were 0.922 and 0.617 for observer A and 0.914 and 0.628 for observer B, respectively. In the comparison of the aforementioned ICCs, ICCs of interobserver and test-retest reproducibility for T1ρ mapping were significantly higher than T2 mapping (p < 0.001). The interobserver and test-retest reproducibility of T1ρ mapping were significantly higher than those of T2 mapping for the quantitative assessment of nuclei pulposi of lumbar intervertebral discs.

  19. Human Mesenchymal Stromal Cells Transplantation May Enhance or Inhibit 4T1 Murine Breast Adenocarcinoma through Different Approaches

    Directory of Open Access Journals (Sweden)

    T. Jazedje

    2015-01-01

    Full Text Available The use of Mesenchymal Stromal Cells (MSCs aiming to treat cancer has shown very contradictory results. In an attempt to clarify the contradictory results reported in the literature and the possible role of human fallopian tube Mesenchymal Stromal Cells (htMSCs against breast cancer, the aim of this study was to evaluate the clinical effect of htMSCs in murine mammary adenocarcinoma using two different approaches: (1 coinjections of htMSCs and 4T1 murine tumor cell lineage and (2 injections of htMSCs in mice at the initial stage of mammary adenocarcinoma development. Coinjected animals had a more severe course of the disease and a reduced survival, while tumor-bearing animals treated with 2 intraperitoneal injections of 106 htMSCs showed significantly reduced tumor growth and increased lifespan as compared with control animals. Coculture of htMSCs and 4T1 tumor cells revealed an increase in IL-8 and MCP-1 and decreased VEGF production. For the first time, we show that MSCs isolated from a single source and donor when injected in the same animal model and tumor can lead to opposite results depending on the experimental protocol. Also, our results demonstrated that htMSCs can have an inhibitory effect on the development of murine mammary adenocarcinoma.

  20. Lumazine Synthase Protein Nanoparticle-Gd(III)-DOTA Conjugate as a T1 contrast agent for high-field MRI.

    Science.gov (United States)

    Song, YoungKyu; Kang, Young Ji; Jung, Hoesu; Kim, Hansol; Kang, Sebyung; Cho, HyungJoon

    2015-10-23

    With the applications of magnetic resonance imaging (MRI) at higher magnetic fields increasing, there is demand for MRI contrast agents with improved relaxivity at higher magnetic fields. Macromolecule-based contrast agents, such as protein-based ones, are known to yield significantly higher r1 relaxivity at low fields, but tend to lose this merit when used as T1 contrast agents (r1/r2 = 0.5 ~ 1), with their r1 decreasing and r2 increasing as magnetic field strength increases. Here, we developed and characterized an in vivo applicable magnetic resonance (MR) positive contrast agent by conjugating Gd(III)-chelating agent complexes to lumazine synthase isolated from Aquifex aeolicus (AaLS). The r1 relaxivity of Gd(III)-DOTA-AaLS-R108C was 16.49 mM(-1)s(-1) and its r1/r2 ratio was 0.52 at the magnetic field strength of 7 T. The results of 3D MR angiography demonstrated the feasibility of vasculature imaging within 2 h of intravenous injection of the agent and a significant reduction in T1 values were observed in the tumor region 7 h post-injection in the SCC-7 flank tumor model. Our findings suggest that Gd(III)-DOTA-AaLS-R108C could serve as a potential theranostic nanoplatform at high magnetic field strength.

  1. Educational Interactive eBook for Newly Diagnosed Children with T1DM: Children’s Role in Design

    Directory of Open Access Journals (Sweden)

    Damyanka Tsvyatkova

    2015-12-01

    Full Text Available Some of the central concerns in technology development for healthcare interventions in Type 1 Diabetes Mellitus (T1DM are how to involve young patients and their families in the design process and what methods, including artbased activities, would best facilitate a child expressing their innermost feelings when applying child-centered and participatory approaches. This paper describes a variety of artbased tools and methods (e.g. Cooperative Inquiry (CI and Informant Design (ID used in the creative design processes for defining features and eliciting the content of the stories, plots, roles, characters, images, animations, languages, etc., that will inform the design of an educational interactive eBook for newly diagnosed children (aged 8-12 years with T1DM. The articulation of design ideas through modeling plasticine figures, drawing and thinking aloud were generated and collected in three workshop sessions organized for diabetic and healthy children who had different roles in and contributions to the design process. Successfully collected data will be used to build a series of low fidelity paper based eBook prototypes.

  2. A novel design of feedback control system for plasma horizontal position in IR-T1 tokamak

    Energy Technology Data Exchange (ETDEWEB)

    Naghidokht, A.; Khodabakhsh, R. [Department of physics, Urmia University, Urmia (Iran, Islamic Republic of); Salar Elahi, A., E-mail: Salari_phy@yahoo.com [Plasma Physics Research Center, Science and Research Branch, Islamic Azad University, Tehran (Iran, Islamic Republic of); Ghoranneviss, M. [Plasma Physics Research Center, Science and Research Branch, Islamic Azad University, Tehran (Iran, Islamic Republic of)

    2016-06-15

    Determination of accurate plasma horizontal position during plasma discharge is essential to transport it to a control system based on feedback. By using the plasma-circuits linearized model, Proportional Integral Derivative (PID) based controllers and a first order transfer function representing the power supply (PS) dynamics of vertical coil system for IR-T1 tokamak, we analyzed step feedback response of the overall system of IR-T1 tokamak and corresponding Bode diagrams for two cases with and without the plasma resistance and the eddy currents distribution. Also we did experiments for determination of plasma horizontal displacement in this tokamak. This work is done by four magnetic probes that are installed on the circular contour of the tokamak. This data used as input to the feedback controller to validate the performance of it. Results of feedback response analysis show that the controller has good performance. Due to approximations in the controller design, construction, installation and implementation of the controller is necessary and this is the purpose of our future works.

  3. T1 nuclear magnetic relaxation dispersion of hyperpolarized sodium and cesium hydrogencarbonate-(13) C.

    Science.gov (United States)

    Martínez-Santiesteban, Francisco M; Dang, Thien Phuoc; Lim, Heeseung; Chen, Albert P; Scholl, Timothy J

    2017-09-01

    In vivo pH mapping in tissue using hyperpolarized hydrogencarbonate-(13) C has been proposed as a method to study tumor growth and treatment and other pathological conditions related to pH changes. The finite spin-lattice relaxation times (T1 ) of hyperpolarized media are a significant limiting factor for in vivo imaging. Relaxation times can be measured at standard magnetic fields (1.5 T, 3.0 T etc.), but no such data are available at low fields, where T1 values can be significantly shorter. This information is required to determine the potential loss of polarization as the agent is dispensed and transported from the polarizer to the MRI scanner. The purpose of this study is to measure T1 dispersion from low to clinical magnetic fields (0.4 mT to 3.0 T) of different hyperpolarized hydrogencarbonate formulations previously proposed in the literature for in vivo pH measurements. (13) C-enriched cesium and sodium hydrogencarbonate preparations were hyperpolarized using dynamic nuclear polarization, and the T1 values of different samples were measured at different magnetic field strengths using a fast field-cycling relaxometer and a 3.0 T clinical MRI system. The effects of deuterium oxide as a dissolution medium for sodium hydrogencarbonate were also analyzed. This study finds that the cesium formulation has slightly shorter T1 values compared with the sodium preparation. However, the higher solubility of cesium hydrogencarbonate-(13) C means it can be polarized at greater concentration, using less trityl radical than sodium hydrogencarbonate-(13) C. This study also establishes that the preparation and handling of sodium hydrogencarbonate formulations in relation to cesium hydrogencarbonate is more difficult, due to the higher viscosity and lower achievable concentrations, and that deuterium oxide significantly increases the T1 of sodium hydrogencarbonate solutions. Finally, this work also investigates the influence of pH on the spin-lattice relaxation of cesium

  4. Highly monodisperse low-magnetization magnetite nanocubes as simultaneous T1-T2 MRI contrast agents

    Science.gov (United States)

    Sharma, V. K.; Alipour, A.; Soran-Erdem, Z.; Aykut, Z. G.; Demir, H. V.

    2015-06-01

    We report the first study of highly monodisperse and crystalline iron oxide nanocubes with sub-nm controlled size distribution (9.7 +/- 0.5 nm in size) that achieve simultaneous contrast enhancement in both T1- and T2-weighted magnetic resonance imaging (MRI). Here, we confirmed the magnetite structure of iron oxide nanocubes by X-ray diffraction (XRD), selected area electron diffraction (SAED) pattern, optical absorption and Fourier transformed infrared (FT-IR) spectra. These magnetite nanocubes exhibit superparamagnetic and paramagnetic behavior simultaneously by virtue of their finely controlled shape and size. The magnetic measurements reveal that the magnetic moment values are favorably much lower because of the small size and cubic shape of the nanoparticles, which results in an enhanced spin canting effect. As a proof-of-concept demonstration, we showed their potential as dual contrast agents for both T1- and T2-weighted MRI via phantom studies, in vivo imaging and relaxivity measurements. Therefore, these low-magnetization magnetite nanocubes, while being non-toxic and bio-compatible, hold great promise as excellent dual-mode T1 and T2 contrast agents for MRI.We report the first study of highly monodisperse and crystalline iron oxide nanocubes with sub-nm controlled size distribution (9.7 +/- 0.5 nm in size) that achieve simultaneous contrast enhancement in both T1- and T2-weighted magnetic resonance imaging (MRI). Here, we confirmed the magnetite structure of iron oxide nanocubes by X-ray diffraction (XRD), selected area electron diffraction (SAED) pattern, optical absorption and Fourier transformed infrared (FT-IR) spectra. These magnetite nanocubes exhibit superparamagnetic and paramagnetic behavior simultaneously by virtue of their finely controlled shape and size. The magnetic measurements reveal that the magnetic moment values are favorably much lower because of the small size and cubic shape of the nanoparticles, which results in an enhanced spin

  5. Geometrically confined ultrasmall gadolinium oxide nanoparticles boost the T1 contrast ability

    Science.gov (United States)

    Ni, Kaiyuan; Zhao, Zhenghuan; Zhang, Zongjun; Zhou, Zijian; Yang, Li; Wang, Lirong; Ai, Hua; Gao, Jinhao

    2016-02-01

    High-performance magnetic resonance imaging (MRI) contrast agents and novel contrast enhancement strategies are urgently needed for sensitive and accurate diagnosis. Here we report a strategy to construct a new T1 contrast agent based on the Solomon-Bloembergen-Morgan (SBM) theory. We loaded the ultrasmall gadolinium oxide nanoparticles into worm-like interior channels of mesoporous silica nanospheres (Gd2O3@MSN nanocomposites). This unique structure endows the nanocomposites with geometrical confinement, high molecular tumbling time, and a large coordinated number of water molecules, which results in a significant enhancement of the T1 contrast with longitudinal proton relaxivity (r1) as high as 45.08 mM-1 s-1. Such a high r1 value of Gd2O3@MSN, compared to those of ultrasmall Gd2O3 nanoparticles and gadolinium-based clinical contrast agents, is mainly attributed to the strong geometrical confinement effect. This strategy provides new guidance for developing various high-performance T1 contrast agents for sensitive imaging and disease diagnosis.High-performance magnetic resonance imaging (MRI) contrast agents and novel contrast enhancement strategies are urgently needed for sensitive and accurate diagnosis. Here we report a strategy to construct a new T1 contrast agent based on the Solomon-Bloembergen-Morgan (SBM) theory. We loaded the ultrasmall gadolinium oxide nanoparticles into worm-like interior channels of mesoporous silica nanospheres (Gd2O3@MSN nanocomposites). This unique structure endows the nanocomposites with geometrical confinement, high molecular tumbling time, and a large coordinated number of water molecules, which results in a significant enhancement of the T1 contrast with longitudinal proton relaxivity (r1) as high as 45.08 mM-1 s-1. Such a high r1 value of Gd2O3@MSN, compared to those of ultrasmall Gd2O3 nanoparticles and gadolinium-based clinical contrast agents, is mainly attributed to the strong geometrical confinement effect. This strategy

  6. Clinical Impact of T1 Slope Minus Cervical Lordosis Following Multilevel Posterior Cervical Fusion Surgery: A Minimum 2-year Follow-Up Data.

    Science.gov (United States)

    Hyun, Seung-Jae; Kim, Ki-Jeong; Jahng, Tae-Ahn; Kim, Hyun-Jib

    2017-05-25

    Retrospective study. To assess the longer term relationship between sagittal alignment of the cervical spine and patient-reported health-related quality-of-life (HRQOL) scores following multilevel posterior cervical fusion, and to explore whether an analog of T1 slope - C2-C7 lordosis ('T1S-CL') impacts on patients' clinical outcomes. A 6-month follow-up study demonstrated that, similar to the thoracolumbar spine, the severity of disability increases with sagittal malalignment following cervical reconstruction surgery. From 2007-2014, 31 consecutive patients having multilevel posterior cervical fusion for cervical stenosis, myelopathy, and deformities met inclusion criteria. To determine the true impact of the alignment on HRQOL, patients who have pseudarthrosis, a misplaced screw, junctional pathologies, or adjacent level disc herniation were excluded. Radiographic measurements included: C0-C2 lordosis, C2-C7 lordosis, C2-C7 sagittal vertical axis (SVA), T1 slope, and T1S-CL. Pearson correlation coefficients were calculated between pairs of radiographic measures and HRQOL. C2-C7 SVA positively correlated with neck disability index (NDI) scores (r = 0.550). For significant correlations between C2-C7 SVA and NDI scores, regression models predicted a threshold C2-C7 SVA value of 43.5 mm, beyond which correlations were most significant. The T1S-CL also correlated positively with C2-C7 SVA and NDI scores (r = 0.827 and r = 0.618, respectively). Results of the regression analysis indicated that a C2-C7 SVA value of 43.5 mm corresponded to a T1S-CL value of 22.2°. This minimum 2-year follow-up study showed that disability of the neck increased with cervical sagittal malalignment following surgical reconstruction and a greater T1S-CL mismatch was associated with a greater degree of cervical malalignment. Specifically, a T1S-CL mismatch greater than 22.2° corresponded to severe disability (NDI>25) and positive cervical sagittal malalignment, defined as C2

  7. Protection against T1DM-Induced Bone Loss by Zinc Supplementation: Biomechanical, Histomorphometric, and Molecular Analyses in STZ-Induced Diabetic Rats.

    Directory of Open Access Journals (Sweden)

    Raul Hernandes Bortolin

    Full Text Available Several studies have established an association between diabetes and alterations in bone metabolism; however, the underlying mechanism is not well established. Although zinc is recognized as a potential preventive agent against diabetes-induced bone loss, there is no evidence demonstrating its effect in chronic diabetic conditions. This study evaluated the effects of zinc supplementation in a chronic (90 days type 1 diabetes-induced bone-loss model. Male Wistar rats were distributed in three groups: control, type 1 diabetes mellitus (T1DM, and T1DM plus zinc supplementation (T1DMS. Serum biochemical analysis; tibia histomorphometric, biomechanical, and collagen-content analyses; and femur mRNA expression were evaluated. Relative to T1DM, the zinc-supplemented group showed increased histomorphometric parameters such as TbWi and BAr and decreased TbSp, increased biomechanical parameters (maximum load, stiffness, ultimate strain, and Young's modulus, and increased type I collagen content. Interestingly, similar values for these parameters were observed between the T1DMS and control groups. These results demonstrate the protective effect of zinc on the maintenance of bone strength and flexibility. In addition, downregulation of OPG, COL1A, and MMP-9 genes was observed in T1DMS, and the anabolic effects of zinc were evidenced by increased OC expression and serum ALP activity, both related to osteoblastogenesis, demonstrating a positive effect on bone formation. In contrast, T1DM showed excessive bone loss, observed through reduced histomorphometric and biomechanical parameters, characterizing diabetes-associated bone loss. The bone loss was also observed through upregulation of OPG, COL1A, and MMP-9 genes. In conclusion, zinc showed a positive effect on the maintenance of bone architecture and biomechanical parameters. Indeed, OC upregulation and control of expression of OPG, COL1A, and MMP-9 mRNAs, even in chronic hyperglycemia, support an anabolic

  8. Protection against T1DM-Induced Bone Loss by Zinc Supplementation: Biomechanical, Histomorphometric, and Molecular Analyses in STZ-Induced Diabetic Rats.

    Science.gov (United States)

    Bortolin, Raul Hernandes; da Graça Azevedo Abreu, Bento João; Abbott Galvão Ururahy, Marcela; Costa de Souza, Karla Simone; Bezerra, João Felipe; Loureiro, Melina Bezerra; da Silva, Flávio Santos; Marques, Dáfiny Emanuele da Silva; Batista, Angélica Amanda de Sousa; Oliveira, Gisele; Luchessi, André Ducati; Lima, Valéria Morgiana Gualberto Duarte Moreira; Miranda, Carlos Eduardo Saraiva; Lia Fook, Marcus Vinicius; Almeida, Maria das Graças; de Rezende, Luciana Augusto; de Rezende, Adriana Augusto

    2015-01-01

    Several studies have established an association between diabetes and alterations in bone metabolism; however, the underlying mechanism is not well established. Although zinc is recognized as a potential preventive agent against diabetes-induced bone loss, there is no evidence demonstrating its effect in chronic diabetic conditions. This study evaluated the effects of zinc supplementation in a chronic (90 days) type 1 diabetes-induced bone-loss model. Male Wistar rats were distributed in three groups: control, type 1 diabetes mellitus (T1DM), and T1DM plus zinc supplementation (T1DMS). Serum biochemical analysis; tibia histomorphometric, biomechanical, and collagen-content analyses; and femur mRNA expression were evaluated. Relative to T1DM, the zinc-supplemented group showed increased histomorphometric parameters such as TbWi and BAr and decreased TbSp, increased biomechanical parameters (maximum load, stiffness, ultimate strain, and Young's modulus), and increased type I collagen content. Interestingly, similar values for these parameters were observed between the T1DMS and control groups. These results demonstrate the protective effect of zinc on the maintenance of bone strength and flexibility. In addition, downregulation of OPG, COL1A, and MMP-9 genes was observed in T1DMS, and the anabolic effects of zinc were evidenced by increased OC expression and serum ALP activity, both related to osteoblastogenesis, demonstrating a positive effect on bone formation. In contrast, T1DM showed excessive bone loss, observed through reduced histomorphometric and biomechanical parameters, characterizing diabetes-associated bone loss. The bone loss was also observed through upregulation of OPG, COL1A, and MMP-9 genes. In conclusion, zinc showed a positive effect on the maintenance of bone architecture and biomechanical parameters. Indeed, OC upregulation and control of expression of OPG, COL1A, and MMP-9 mRNAs, even in chronic hyperglycemia, support an anabolic and protective

  9. Rapid and simple determination of T1 relaxation times in time-domain NMR by Continuous Wave Free Precession sequence

    Science.gov (United States)

    Moraes, Tiago Bueno; Monaretto, Tatiana; Colnago, Luiz Alberto

    2016-09-01

    Longitudinal (T1) and transverse (T2) relaxation times have been widely used in time-domain NMR (TD-NMR) to determine several physicochemical properties of petroleum, polymers, and food products. The measurement of T2 through the CPMG pulse sequence has been used in most of these applications because it denotes a rapid, robust method. On the other hand, T1 has been occasionally used in TD-NMR due to the long measurement time required to collect multiple points along the T1 relaxation curve. Recently, several rapid methods to measure T1 have been proposed. Those methods based upon single shot, known as Continuous Wave Free Precession (CWFP) pulse sequences, have been employed in the simultaneous measurement of T1 and T2 in a rapid fashion. However, these sequences can be used exclusively in instrument featuring short dead time because the magnitude of the signal at thermal equilibrium is required. In this paper, we demonstrate that a special CWFP sequence with a low flip angle can be a simple and rapid method to measure T1 regardless of instruments dead time. Experimental results confirmed that the method called CWFP-T1 may be used to measure both single T1 value and T1 distribution in heterogeneous samples. Therefore, CWFP-T1 sequence can be a feasible alternative to CPMG in the determination of physicochemical properties, particularly in processes where fast protocols are requested such as industrial applications.

  10. Rotational level involvement in the T1-->S0 intersystem crossing transition in thiophosgene.

    Science.gov (United States)

    Rashev, Svetoslav; Moule, David C

    2009-04-07

    We propose and develop theoretically a general mechanism for the involvement of rotational motion into the nonradiative transitions that occur in an isolated polyatomic molecule. The treatment is based on the different rotational constants and different (asymmetric top-symmetric top) molecular structures in the two combining electronic states. We focus our attention on the T(1)-->S(0) intersystem crossing (ISC) transition in thiophosgene and show how the rotational mechanism could lead to a considerable enhancement in the effective level density for the process. Inserting the rotational mechanism into our recently developed technique and algorithm for combined spin-orbit coupling+intramolecular vibrational redistribution analysis, we have carried out large-scale calculations that have led to a better understanding of the ISC (T(1)-->S(0)) in thiophosgene.

  11. AdS$_5$ vacua from type IIB supergravity on $T^{1,1}$

    CERN Document Server

    Louis, Jan

    2016-01-01

    We study maximally supersymmetric Anti-de Sitter backgrounds in consistent N=2 truncations of type IIB supergravity compactified on the Sasaki-Einstein manifold $T^{1,1}$. In particular, we focus on truncations that contain fields coming from the nontrivial second and third cohomology forms on $T^{1,1}$. These give rise to N=2 supergravity coupled to two vector- and two hypermultiplets (Betti-vector truncation) or one vector- and three hypermultiplets (Betti-hyper truncation), respectively. We find that both truncations admit AdS$_5$ backgrounds with the gauge group always being broken but containing at least an $U(1)_R$ factor. Moreover, in both cases we show that the moduli space of AdS vacua is nontrivial and of maximal dimension. Finally, we explicitly compute the metrics on these moduli spaces.

  12. T1-MRI Fluorescent Iron Oxide Nanoparticles by Microwave Assisted Synthesis

    Science.gov (United States)

    Bhavesh, Riju; Lechuga-Vieco, Ana V.; Ruiz-Cabello, Jesús; Herranz, Fernando

    2015-01-01

    Iron oxide nanoparticles have long been studied as a T2 contrast agent in MRI due to their superparamagnetic behavior. T1-based positive contrast, being much more favorable for clinical application due to brighter and more accurate signaling is, however, still limited to gadolinium- or manganese-based imaging tools. Though being the only available commercial positive-contrast agents, they lack an efficient argument when it comes to biological toxicity and their circulatory half-life in blood. The need arises to design a biocompatible contrast agent with a scope for easy surface functionalization for long circulation in blood and/or targeted imaging. We hereby propose an extremely fast microwave synthesis for fluorescein-labeled extremely-small iron oxide nanoparticles (fdIONP), in a single step, as a viable tool for cell labeling and T1-MRI. We demonstrate the capabilities of such an approach through high-quality magnetic resonance angiographic images of mice.

  13. T1-MRI Fluorescent Iron Oxide Nanoparticles by Microwave Assisted Synthesis

    Directory of Open Access Journals (Sweden)

    Riju Bhavesh

    2015-11-01

    Full Text Available Iron oxide nanoparticles have long been studied as a T2 contrast agent in MRI due to their superparamagnetic behavior. T1-based positive contrast, being much more favorable for clinical application due to brighter and more accurate signaling is, however, still limited to gadolinium- or manganese-based imaging tools. Though being the only available commercial positive-contrast agents, they lack an efficient argument when it comes to biological toxicity and their circulatory half-life in blood. The need arises to design a biocompatible contrast agent with a scope for easy surface functionalization for long circulation in blood and/or targeted imaging. We hereby propose an extremely fast microwave synthesis for fluorescein-labeled extremely-small iron oxide nanoparticles (fdIONP, in a single step, as a viable tool for cell labeling and T1-MRI. We demonstrate the capabilities of such an approach through high-quality magnetic resonance angiographic images of mice.

  14. Parametric techniques for characterizing myocardial tissue by magnetic resonance imaging (part 1): T1 mapping.

    Science.gov (United States)

    Perea Palazón, R J; Ortiz Pérez, J T; Prat González, S; de Caralt Robira, T M; Cibeira López, M T; Solé Arqués, M

    2016-01-01

    The development of myocardial fibrosis is a common process in the appearance of ventricular dysfunction in many heart diseases. Magnetic resonance imaging makes it possible to accurately evaluate the structure and function of the heart, and its role in the macroscopic characterization of myocardial fibrosis by late enhancement techniques has been widely validated clinically. Recent studies have demonstrated that T1-mapping techniques can quantify diffuse myocardial fibrosis and the expansion of the myocardial extracellular space in absolute terms. However, further studies are necessary to validate the usefulness of this technique in the early detection of tissue remodeling at a time when implementing early treatment would improve a patient's prognosis. This article reviews the state of the art for T1 mapping of the myocardium, its clinical applications, and its limitations. Copyright © 2016 SERAM. Published by Elsevier España, S.L.U. All rights reserved.

  15. Extrahepatic portal vein obstruction with parkinsonism and symmetric hyperintense basal ganglia on T1 weighted MRI

    Directory of Open Access Journals (Sweden)

    Jayalakshmi Sita

    2006-01-01

    Full Text Available Abnormal high signal in the globus pallidus on T1 weighted magnetic resonance imaging (MRI of the brain has been well described in patients with chronic liver disease. It may be related to liver dysfunction or portal-systemic shunting. We report a case of extra hepatic portal vein obstruction with portal hypertension and esophageal varices that presented with extra pyramidal features. T1 weighted MRI brain scans showed increased symmetrical signal intensities in the basal ganglia. Normal hepatic function in this patient emphasizes the role of portal- systemic communications in the development of these hyperintensities, which may be due to deposition of paramagnetic substances like manganese in the basal ganglia.

  16. The Relationship between T1 Sagittal Angle and Sagittal Balance: A Retrospective Study of 119 Healthy Volunteers.

    Science.gov (United States)

    Yang, Mingyuan; Yang, Changwei; Ni, Haijian; Zhao, Yuechao; Li, Ming

    2016-01-01

    T1 sagittal angle has been reported to be used as a parameter for assessing sagittal balance and cervical lordosis. However, no study has been performed to explore the relationship between T1 sagittal angle and sagittal balance, and whether T1 sagittal angle could be used for osteotomy guidelines remains unknown. The aim of our study is to explore the relationship between T1 sagittal angle and sagittal balance, determine the predictors for T1 sagittal angle, and determine whether T1 sagittal angle could be used for osteotomy guidelines to restore sagittal balance. Medical records of healthy volunteers in our outpatient clinic from January 2014 to August 2015 were reviewed, and their standing full-spine lateral radiographs were evaluated. Demographic and radiological parameters were collected and analyzed, including age, gender, T1 sagittal angle, maxTK, maxLL, SS, PT, and PI. Correlation coefficients between T1 sagittal angle and other spinopelvic parameters were determined. In addition, multiple regression analysis was performed to establish predictive radiographic parameters for T1 sagittal angle as the primary contributors. A total of 119 healthy volunteers were recruited in our study with a mean age of 34.7 years. It was found that T1 sagittal angle was correlated with maxTK with very good significance (r = 0.697, Psagittal angle could be predicted by using the following regression equation: T1 sagittal angle = 0.6 * maxTK-0.2 * maxLL + 8. In the healthy population, T1 sagittal angle could be considered as a useful parameter for sagittal balance; however, it could not be thoroughly replaced for SVA. maxTK was the primary contributor to T1 sagittal angle. According to this equation, we could restore sagittal balance by surgically changing thoracic kyphosis and lumbar lordosis, which could serve as a guideline for osteotomy.

  17. Calcium signaling properties of a thyrotroph cell line, mouse TαT1 cells.

    Science.gov (United States)

    Tomić, Melanija; Bargi-Souza, Paula; Leiva-Salcedo, Elias; Nunes, Maria Tereza; Stojilkovic, Stanko S

    2015-12-01

    T1 cells are mouse thyrotroph cell line frequently used for studies on thyroid-stimulating hormone beta subunit gene expression and other cellular functions. Here we have characterized calcium-signaling pathways in TαT1 cells, an issue not previously addressed in these cells and incompletely described in native thyrotrophs. TαT1 cells are excitable and fire action potentials spontaneously and in response to application of thyrotropin-releasing hormone (TRH), the native hypothalamic agonist for thyrotrophs. Spontaneous electrical activity is coupled to small amplitude fluctuations in intracellular calcium, whereas TRH stimulates both calcium mobilization from intracellular pools and calcium influx. Non-receptor-mediated depletion of intracellular pool also leads to a prominent facilitation of calcium influx. Both receptor and non-receptor stimulated calcium influx is substantially attenuated but not completely abolished by inhibition of voltage-gated calcium channels, suggesting that depletion of intracellular calcium pool in these cells provides a signal for both voltage-independent and -dependent calcium influx, the latter by facilitating the pacemaking activity. These cells also express purinergic P2Y1 receptors and their activation by extracellular ATP mimics TRH action on calcium mobilization and influx. The thyroid hormone triiodothyronine prolongs duration of TRH-induced calcium spikes during 30-min exposure. These data indicate that TαT1 cells are capable of responding to natively feed-forward TRH signaling and intrapituitary ATP signaling with acute calcium mobilization and sustained calcium influx. Amplification of TRH-induced calcium signaling by triiodothyronine further suggests the existence of a pathway for positive feedback effects of thyroid hormones probably in a non-genomic manner.

  18. 4T1 Murine Mammary Carcinoma Cells Enhance Macrophage-Mediated Innate Inflammatory Responses

    OpenAIRE

    Laurence Madera; Anna Greenshields; Power Coombs, Melanie R.; Hoskin, David W.

    2015-01-01

    Tumor progression and the immune response are intricately linked. While it is known that cancers alter macrophage inflammatory responses to promote tumor progression, little is known regarding how cancers affect macrophage-dependent innate host defense. In this study, murine bone-marrow-derived macrophages (BMDM) were exposed to murine carcinoma-conditioned media prior to assessment of the macrophage inflammatory response. BMDMs exposed to 4T1 mammary carcinoma-conditioned medium demonstrated...

  19. Transoral CO2 Laser Microsurgery Outcomes for Early Glottic Carcinomas T1-T2

    Science.gov (United States)

    Chiesa Estomba, Carlos Miguel; Reinoso, Frank Alberto Betances; Velasquez, Alejandra Osorio; Fernandez, Jose Luis Rodriguez; Conde, Jose Luis Fariña; Hidalgo, Carmelo Santidrian

    2016-01-01

    Introduction  Transoral laser microsurgery (TLM) has won territory in larynx oncology, establishing itself as an effective option in treatment of glottic, supraglottic, and hypopharynx tumors. Its advantages include limited resections, a reduction in number of tracheostomies, and the use of nasogastric tubes. Moreover, its oncological benefits are similar to those from open surgery in patients with early or advanced stages, when correctly selected. Objective  The objective of this study is to review oncologic outcomes obtained with the treatment of a series of glottic tumors, treated by TLM. Methods  Retrospective analysis of patients previously untreated, diagnosed with squamous cell carcinoma of the glottis (T1a, T1b, T2) in a tertiary university hospital. Endpoints for analysis were local control, overall and disease-specific survival, and larynx preservation rate. Results  The study group included 58 patients that met the inclusion criteria: 57 (98.3%) men and 1 (1.7%) woman. Mean age was 65.5 ± 10.7 years (Min: 46/Max: 88). The tumor stages of the patients included were 30 T1a, 11 (19%) T1b, and 17 (29.3%) T2. Three-year overall survival rate was 89.7% (Fig. 1), and three-year disease-specific survival rate was 96.5%, three-year local control rate was 98.3%, and three-year organ preservation rate was 98.3%. Conclusion  TLM is a safe and effective option in the treatment of glottis carcinomas, associated with less morbidity and a high percentage of local control, overall survival, specific survival, and organ preservation. PMID:27413401

  20. Transoral CO2 Laser Microsurgery Outcomes for Early Glottic Carcinomas T1-T2

    Directory of Open Access Journals (Sweden)

    Chiesa Estomba, Carlos Miguel

    2016-02-01

    Full Text Available Introduction Transoral laser microsurgery (TLM has won territory in larynx oncology, establishing itself as an effective option in treatment of glottic, supraglottic, and hypopharynx tumors. Its advantages include limited resections, a reduction in number of tracheostomies, and the use of nasogastric tubes. Moreover, its oncological benefits are similar to those from open surgery in patients with early or advanced stages, when correctly selected. Objective The objective of this study is to review oncologic outcomes obtained with the treatment of a series of glottic tumors, treated by TLM. Methods Retrospective analysis of patients previously untreated, diagnosed with squamous cell carcinoma of the glottis (T1a, T1b, T2 in a tertiary university hospital. Endpoints for analysis were local control, overall and disease-specific survival, and larynx preservation rate. Results The study group included 58 patients that met the inclusion criteria: 57 (98.3% men and 1 (1.7% woman. Mean age was 65.5 ± 10.7 years (Min: 46/Max: 88. The tumor stages of the patients included were 30 T1a, 11 (19% T1b, and 17 (29.3% T2. Three-year overall survival rate was 89.7% (Fig. 1, and three-year disease-specific survival rate was 96.5%, three-year local control rate was 98.3%, and three-year organ preservation rate was 98.3%. Conclusion TLM is a safe and effective option in the treatment of glottis carcinomas, associated with less morbidity and a high percentage of local control, overall survival, specific survival, and organ preservation.

  1. Environmental Consequences of Nanotechnologies: Nanoparticle Dispersion in Aqueous Media: SOP-T-1

    Science.gov (United States)

    2015-02-01

    ER D C/ EL S R- 15 -2 Environmental Consequences of Nanotechnologies Nanoparticle Dispersion in Aqueous Media: SOP-T-1 En vi ro nm en...dispersions of nanoparticles (NPs) for use in bioassay media for exposures/characterizations are a crucial need in ecotoxicology assays. The present...protocol provides guidance and step-by-step methods for: (1) creating a working stock from nanoparticle powder and nanoparticle aqueous suspensions

  2. Fetal gastrointestinal MRI: all that glitters in T1 is not necessarily colon

    Energy Technology Data Exchange (ETDEWEB)

    Colombani, Marina [La Timone Children' s Hospital, Service de Radiopediatrie, Marseille (France); Ferry, Mathilde [Groupe Rennais d' Imagerie Medicale, Service de Radiologie, Rennes (France); Garel, Catherine [Hopital d' Enfants Armand-Trousseau, Service de Radiologie, Paris (France); Cassart, Marie [Erasme Hospital, Medical Imaging, Brussels (Belgium); Couture, Alain [Hopital Arnaud de Villeneuve, Pediatric Radiology, Montpellier (France); Guibaud, Laurent [Hopital Femme Mere Enfant, Pediatric and Fetal Imaging, Lyon (France); Avni, Fred [Erasme Hospital, Radiology, Brussels (Belgium); Gorincour, Guillaume [La Timone Children' s Hospital, Pediatric Radiology, Marseille (France)

    2010-07-15

    It has been described that both the colon and distal ileum present with a physiological hypersignal on T1-weighted sequences during the second and third trimesters of pregnancy because of their protein-rich meconium content, it was unclear whether the normal characteristics that have been described on fetal MRI can be applied to gastrointestinal (GI) obstructions. To analyse the localisation value of T1 hypersignal within dilated bowel loops in fetuses with gastrointestinal tract obstruction. A retrospective 4-year multicentre study analysing cases of fetal GI obstruction in which MRI demonstrated T1 hypersignal content in the dilated loops. Data collected included gestational age (GA) at diagnosis, bowel appearance on US, CFTR gene mutations and amniotic levels of gastrointestinal enzymes. The suggested prenatal diagnosis was eventually compared to postnatal imaging and surgery. Eleven patients were included. The median GA at US diagnosis was 23 weeks (range 13-32). In eight cases there was a single dilated loop, while several segments were affected in three. The median GA at MRI was 29 weeks (range 23-35). One case presented with cystic fibrosis mutations. Final prenatally suspected diagnoses were distal ileal atresia or colon in nine cases and proximal atresia in two. Postnatal findings were proximal jejunal atresia in nine cases and meconium ileus in two. In five cases the surgical findings demonstrated short bowel syndrome. In cases of fetal occlusion, T1 hypersignal should not be considered as a sign of distal ileal or colonic occlusion. The obstruction may be proximal, implying a risk of small bowel syndrome, which requires adequate parental counselling. (orig.)

  3. [Early Detection of Manganese Intoxication Based on Occupational History and T1-weighted MRI].

    Science.gov (United States)

    Fukutake, Toshio; Yano, Hajime; Kushida, Ryutaro; Sunada, Yoshihide

    2016-02-01

    Manganese regulates many enzymes and is essential for normal cell function. Chronic manganese intoxication has an insidious and progressive course terminating to atypical parkinsonism with little therapeutic efficacy. For subjects with chronic manganese exposure such as welders, manganese intoxication can be detected early based on the presence of hyperintensity in the globus pallidus on T(1)-weighted MRI and abnormally high urinary excretion of manganese with a chelating agent even in cases of normal serum/urine level of manganese.

  4. Degenerative disc disease of the lumbar spine: a prospective comparison of fast T1-weighted fluid-attenuated inversion recovery and T1-weighted turbo spin echo MR imaging

    Energy Technology Data Exchange (ETDEWEB)

    Erdem, L. Oktay [Department of Radiology, Zonguldak Karaelmas University, School of Medicine, 6700 Kozlu, Zonguldak (Turkey)]. E-mail: sunarerdem@yahoo.com; Erdem, C. Zuhal [Department of Radiology, Zonguldak Karaelmas University, School of Medicine, 6700 Kozlu, Zonguldak (Turkey); Acikgoz, Bektas [Department of Neurosurgery, Zonguldak Karaelmas University, School of Medicine, Zonguldak (Turkey); Gundogdu, Sadi [Department of Radiology, Zonguldak Karaelmas University, School of Medicine, 6700 Kozlu, Zonguldak (Turkey)

    2005-08-01

    Objective: To compare fast T1-weighted fluid-attenuated inversion recovery (FLAIR) and T1-weighted turbo spin-echo (TSE) imaging of the degenerative disc disease of the lumbar spine. Materials and methods: Thirty-five consecutive patients (19 females, 16 males; mean age 41 years, range 31-67 years) with suspected degenerative disc disease of the lumbar spine were prospectively evaluated. Sagittal images of the lumbar spine were obtained using T1-weighted TSE and fast T1-weighted FLAIR sequences. Two radiologists compared these sequences both qualitatively and quantitatively. Results: On qualitative evaluation, CSF nulling, contrast at the disc-CSF interface, the disc-spinal cord (cauda equina) interface, and the spinal cord (cauda equina)-CSF interface of fast T1-weighted FLAIR images were significantly higher than those for T1-weighted TSE images (P < 0.001). On quantitative evaluation of the first 15 patients, signal-to-noise ratios of cerebrospinal fluid of fast T1-weighted FLAIR imaging were significantly lower than those for T1-weighted TSE images (P < 0.05). Contrast-to-noise ratios of spinal cord/CSF and normal bone marrow/disc for fast T1-weighted FLAIR images were significantly higher than those for T1-weighted TSE images (P < 0.05). Conclusion: Results in our study have shown that fast T1-weighted FLAIR imaging may be a valuable imaging modality in the armamentarium of lumbar spinal T1-weighted MR imaging, because the former technique has definite superior advantages such as CSF nulling, conspicuousness of the normal anatomic structures and changes in the lumbar spinal discogenic disease and image contrast and also almost equally acquisition times.

  5. Renegade homeostatic cytokine responses in T1D: drivers of regulatory/effector T cell imbalance.

    Science.gov (United States)

    Gupta, Shipra; Cerosaletti, Karen; Long, S Alice

    2014-04-01

    Homeostatic cytokines contribute to the balance between regulatory and effector T cells (Tregs and Teffs respectively) and are necessary to maintain peripheral tolerance. These cytokines include IL-2 that supports Treg and IL-7 and IL-15 that drive Teff. In overt settings of lost tolerance (i.e. graft rejection), IL-2 Treg signatures are decreased while IL-7 and IL-15 Teff signatures are often enhanced. Similar cytokine profile imbalances also occur in some autoimmune diseases. In type 1 diabetes (T1D), there are underlying defects in the IL-2 pathway and Teff cytokine blockade can prevent and treat diabetes in NOD mice. In this review, we summarize evidence of IL-2, IL-7 and IL-15 genetic and cellular alterations in T1D patients. We then discuss how the combined effect of these cytokine profiles may together contribute to altered Treg/Teff ratios and functions in T1D. Implications for combination therapies and suggestions for integrated cytokine and Treg/Teff biomarker development are then proposed. Copyright © 2014 Elsevier Inc. All rights reserved.

  6. Assessment of Silent T1-weighted head imaging at 7 T

    Energy Technology Data Exchange (ETDEWEB)

    Costagli, Mauro; Tiberi, Gianluigi; Tosetti, Michela [Imago7 Foundation, Pisa (Italy); IRCCS Stella Maris, Laboratory of Medical Physics and Biotechnologies for Magnetic Resonance, Pisa (Italy); Symms, Mark R. [GE Applied Science Laboratory, Pisa (Italy); Angeli, Lorenzo [University of Pisa, Department of Translational Research and New Technologies in Medicine and Surgery, Pisa (Italy); Kelley, Douglas A.C. [GE Healthcare Technologies, San Francisco, CA (United States); Biagi, Laura [IRCCS Stella Maris, Laboratory of Medical Physics and Biotechnologies for Magnetic Resonance, Pisa (Italy); Farnetani, Andrea [University of Ferrara, Engineering Department, Ferrara (Italy); Materiacustica s.r.l., Ferrara (Italy); Rua, Catarina [University of Pisa, Department of Physics, Pisa (Italy); Donatelli, Graziella [Azienda Ospedaliero-Universitaria Pisana (AOUP), Neuroradiology Unit, Department of Diagnostic and Interventional Radiology, Pisa (Italy); Cosottini, Mirco [Imago7 Foundation, Pisa (Italy); University of Pisa, Department of Translational Research and New Technologies in Medicine and Surgery, Pisa (Italy)

    2016-06-15

    This study aimed to assess the performance of a ''Silent'' zero time of echo (ZTE) sequence for T1-weighted brain imaging using a 7 T MRI system. The Silent sequence was evaluated qualitatively by two neuroradiologists, as well as quantitatively in terms of tissue contrast, homogeneity, signal-to-noise ratio (SNR) and acoustic noise. It was compared to conventional T1-weighted imaging (FSPGR). Adequacy for automated segmentation was evaluated in comparison with FSPGR acquired at 7 T and 1.5 T. Specific absorption rate (SAR) was also measured. Tissue contrast and homogeneity in Silent were remarkable in deep brain structures and in the occipital and temporal lobes. Mean tissue contrast was significantly (p < 0.002) higher in Silent (0.25) than in FSPGR (0.11), which favoured automated tissue segmentation. On the other hand, Silent images had lower SNR with respect to conventional imaging: average SNR of FSPGR was 2.66 times that of Silent. Silent images were affected by artefacts related to projection reconstruction, which nevertheless did not compromise the depiction of brain tissues. Silent acquisition was 35 dB(A) quieter than FSPGR and less than 2.5 dB(A) louder than ambient noise. Six-minute average SAR was <2 W/kg. The ZTE Silent sequence provides high-contrast T1-weighted imaging with low acoustic noise at 7 T. (orig.)

  7. Ultrafast NMR T1 relaxation measurements: probing molecular properties in real time.

    Science.gov (United States)

    Smith, Pieter E S; Donovan, Kevin J; Szekely, Or; Baias, Maria; Frydman, Lucio

    2013-09-16

    The longitudinal relaxation properties of NMR active nuclei carry useful information about the site-specific chemical environments and about the mobility of molecular fragments. Molecular mobility is in turn a key parameter reporting both on stable properties, such as size, as well as on dynamic ones, such as transient interactions and irreversible aggregation. In order to fully investigate the latter, a fast sampling of the relaxation parameters of transiently formed molecular species may be needed. Nevertheless, the acquisition of longitudinal relaxation data is typically slow, being limited by the requirement that the time for which the nucleus relaxes be varied incrementally until a complete build-up curve is generated. Recently, a number of single-shot-inversion-recovery methods have been developed capable of alleviating this need; still, these may be challenged by either spectral resolution restrictions or when coping with very fast relaxing nuclei. Here, we present a new experiment to measure the T1s of multiple nuclear spins that experience fast longitudinal relaxation, while retaining full high-resolution chemical shift information. Good agreement is observed between T1s measured with conventional means and T1s measured using the new technique. The method is applied to the real-time investigation of the reaction between D-xylose and sodium borate, which is in turn elucidated with the aid of ancillary ultrafast and conventional 2D TOCSY measurements. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. HLA class II susceptibility pattern for type 1 diabetes (T1D) in an Iranian population.

    Science.gov (United States)

    Kiani, J; Hajilooi, M; Furst, D; Rezaei, H; Shahryari-Hesami, S; Kowsarifard, S; Zamani, A; Solgi, G

    2015-08-01

    This study aimed to determine the HLA-DRB1/HLA-DQB1 susceptibility and protection pattern for type 1 diabetes (T1D) in a population from Hamadan, north-west of Iran. A total of 133 patients with T1D were tested for HLA-DRB1 and HLA-DQB1 alleles using PCR-SSP compared to 100 ethnic-matched healthy controls. Alleles and haplotypes frequencies were compared between both groups. The most susceptible alleles for disease were HLA-DRB1*03:01, DRB1*04:02, DQB1*02:01 and DQB1*03:02, and protective alleles were HLA-DRB1*07:01, *11:01, *13:01, *14:01 and DRB1*15 and HLA-DQB1*06:01, *06:02 and *06:03. Haplotype analysis revealed that patients with T1D had higher frequencies of DRB1*03:01-DQB1*02:01 (OR = 4.86, P < 10(-7) ) and DRB1*04:02-DQB1*03:02 (OR = 9.93, P < 10(-7) ) and lower frequencies of DRB1*07:01-DQB1*02:01 (P = 0.0005), DRB1*11:01-DQB1*03:01 (P = 0.001), DRB1*13:01-DQB1*06:03 (P = 0.002) and DRB1*15-DQB1*06:01 (P = 0.001) haplotypes compared to healthy controls. Heterozygote combination of both susceptible haplotypes (DR3/DR4) confers the highest risk for T1D (RR = 18.80, P = 4 × 10(-5) ). Additionally, patients with homozygote diplotype, DR3/DR3 and DR4/DR4, showed a similar risk with less extent to heterozygote combination (P = 0.0004 and P = 0.01, respectively). Our findings not only confirm earlier reports from Iranians but also are in line with Caucasians and partly with Asians and some African patients with T1D. Remarkable differences were the identification of DRB1*04:01-DQB1*03:02, DRB1*07:01-DQB1*03:03 and DRB1*16-DQB1*05:02 as neutral and DRB1*13:01-DQB1*06:03 as the most protective haplotypes in this study.

  9. Epidermal growth factor inhibits glycylsarcosine transport and hPepT1 expression in a human intestinal cell line

    DEFF Research Database (Denmark)

    Nielsen, C U; Amstrup, J; Steffansen, B

    2001-01-01

    (max) decreased from 2.61 +/- 0.4 to 1.06 +/- 0.1 nmol x cm(-2) x min(-1) (n = 3, P PepT1 mRNA (using glucose-6-phosphate dehydrogenase mRNA as control......The human intestinal cell line Caco-2 was used as a model system to study the effects of epidermal growth factor (EGF) on peptide transport. EGF decreased apical-to-basolateral fluxes of [(14)C]glycylsarcosine ([(14)C]Gly-Sar) up to 50.2 +/- 3.6% (n = 6) of control values. Kinetic analysis...... of the fluxes showed that maximal flux (V(max)) of transepithelial transport decreased from 3.00 +/- 0.17 nmol x cm(-2) x min(-1) in control cells to 0.50 +/- 0.07 nmol x cm(-2) x min(-1) in cells treated with 5 ng/ml EGF (n = 6, P

  10. New Magnetic Resonance Imaging Index for Renal Fibrosis Assessment: A Comparison between Diffusion-Weighted Imaging and T1 Mapping with Histological Validation

    Science.gov (United States)

    Friedli, I.; Crowe, L. A.; Berchtold, L.; Moll, S.; Hadaya, K.; de Perrot, T.; Vesin, C.; Martin, P.-Y.; de Seigneux, S.; Vallée, J.-P.

    2016-01-01

    A need exists to noninvasively assess renal interstitial fibrosis, a common process to all kidney diseases and predictive of renal prognosis. In this translational study, Magnetic Resonance Imaging (MRI) T1 mapping and a new segmented Diffusion-Weighted Imaging (DWI) technique, for Apparent Diffusion Coefficient (ADC), were first compared to renal fibrosis in two well-controlled animal models to assess detection limits. Validation against biopsy was then performed in 33 kidney allograft recipients (KARs). Predictive MRI indices, ΔT1 and ΔADC (defined as the cortico-medullary differences), were compared to histology. In rats, both T1 and ADC correlated well with fibrosis and inflammation showing a difference between normal and diseased kidneys. In KARs, MRI indices were not sensitive to interstitial inflammation. By contrast, ΔADC outperformed ΔT1 with a stronger negative correlation to fibrosis (R2 = 0.64 against R2 = 0.29 p < 0.001). ΔADC tends to negative values in KARs harboring cortical fibrosis of more than 40%. Using a discriminant analysis method, the ΔADC, as a marker to detect such level of fibrosis or higher, led to a specificity and sensitivity of 100% and 71%, respectively. This new index has potential for noninvasive assessment of fibrosis in the clinical setting. PMID:27439482

  11. Comparison of T1rho and T2 mapping of knee articular cartilage in an asymptomatic population

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Min A; Hong, Suk Joo; Im, A Lan [Dept. of Radiology, Korea University Guro Hospital, Korea University College of Medicine, Seoul (Korea, Republic of); Kang, Chang Ho [Dept. of Radiology, Korea University Anam Hospital, Korea University College of Medicine, Seoul (Korea, Republic of); Kim, Baek Hyun [Dept. of Radiology, Korea University Ansan Hospital, Korea University College of Medicine, Ansan (Korea, Republic of); Kim, In Seong [Siemens Healthcare, Seoul (Korea, Republic of)

    2016-11-15

    To analyze subregional differences in T1rho (T1ρ) and T2 values and their correlation in asymptomatic knee cartilage, and to evaluate angular dependence with magic angles. Six asymptomatic volunteers underwent knee MRI with T1ρ and T2 mapping. T1ρ and T2 values were measured by two radiologists independently, at nine subregions in the medial femoral condyle (MFC) cartilage, at angles of ± 0°, 15°, 35°, 55°, 75° respective to a vertical line (B0) bisecting the width of the distal femur, and at two locations in the patella. Subregional values of T1ρ and T2 were analyzed and significant differences in three divided portions of the MFC (anterior, central, and posterior) were statistically evaluated. Correlation between T1ρ and T2 and angular dependence with magic angles were also assessed for statistical significance. T1ρ values were lowest at +15° and highest at -55°. T2 values were lowest at +75° and highest at +35°. Both T1ρ and T2 were higher in superior patella than inferior patella. T1ρ showed significant differences in the three divided portions of the MFC, while T2 showed significant differences only between central and posterior portions. There was a weak correlation between T1ρ and T2 (r = 0.217, p = 0.127). T1ρ showed more angular dependence than T2. T1ρ and T2 showed different subregional values and angular dependence in asymptomatic knee cartilage with a weak correlation. Awareness of these differences will aid in assessment of cartilage in a specific subregion of the knee.

  12. Effects of intracellular pH, blood, and tissue oxygen tension on T1rho relaxation in rat brain.

    Science.gov (United States)

    Kettunen, Mikko I; Gröhn, Olli H J; Silvennoinen, M Johanna; Penttonen, Markku; Kauppinen, Risto A

    2002-09-01

    The effects of intracellular pH (pH(i)), paramagnetic macroscopic, and microscopic susceptibility on T(1) in the rotating frame (T(1rho)) were studied in rat brain. Intracellular acidosis was induced by hypercapnia and pH(i), T(1rho), T(2), diffusion, and cerebral blood volume (CBV) were quantified. Taking into account the CBV contribution, a prolongation of parenchymal T(1rho) by 4.5% was ascribed to a change in tissue water relaxation caused by a one unit drop in pH(i). Blood T(1rho) was found to prolong linearly with blood oxygenation saturation (Y). The macroscopic susceptibility contribution to parenchymal T(1rho) was assessed both through BOLD and an iron oxide contrast agent, AMI-227. The T(1rho) data from these experiments could be described by intravascular effects with insignificant effects of susceptibility gradients on tissue water. Tissue oxygen tension (PtO(2)) was manipulated and monitored with microelectrodes to assess its plausible contribution to microscopic susceptibility and relaxation. Parenchymal T(1rho) was virtually unaffected by variations in the PtO(2), but T(1) was shortened in hyperoxia and T(2) showed a negative BOLD effect in hypoxia. It is demonstrated that pH(i) directly modulates tissue T(1rho), possibly through its effect on proton exchange; however, neither BOLD nor PtO(2) directly influence tissue T(1rho). The observations are discussed in the light of physicochemical mechanisms contributing to the ischemic T(1rho) changes. Copyright 2002 Wiley-Liss, Inc.

  13. Can C7 Slope Substitute the T1 slope? An Analysis Using Cervical Radiographs and Kinematic MRIs.

    Science.gov (United States)

    Tamai, Koji; Buser, Zorica; Paholpak, Permsak; Seesumpun, Kittipong; Nakamura, Hiroaki; Wang, Jeffrey C

    2017-08-01

    Retrospective analysis of consecutive 45 radiographs and 120 kinematic magnetic resonance images (kMRI) OBJECTIVE.: The aim was to assess the visibility of C7 and T1 endplates on radiographs, and to verify the correlation between C7 or T1 slope and cervical balance parameters using kMRI. Because the T1 slope is not always visible due to the anatomical interference, several studies have used C7 slope instead of T1. However, it is still unclear whether the C7 endplate is more visible on radiographs than T1, and if C7 slope has similarity with T1 slope. The endplate visibility was determined using weight-bearing radiography. Subsequently, using weight-bearing MR images, the C7 slope of upper and lower endplate, T1 slope, C1 inclination, C2 slope, atlas-dens interval (ADI), C2-C7 lordotic angle, cervical sagittal vertical axis (cSVA), cervical tilt, cranial tilt, neck tilt, thoracic inlet angle (TIA) were measured, for the analysis of correlation between three types of slopes and cervical balance parameters. 82% of the upper C7, and 18% of T1 endplate were clearly visible. The upper C7 endplate was significantly visible, whereas T1 endplate was significantly invisible (residual analysis, p < 0.01). Linear regression analysis showed correlation between the upper C7 slope and T1 slope (R = 0.818, p < 0.01) and, lower C7 slope and T1 slope (R = 0.840, p < 0.01). T1 slope significantly correlated with neck tilt, TIA, C2-C7 angle, cSVA, cervical and cranial tilt, but not with the C1 inclination, C2 slope and ADI. Upper and lower C7 slopes showed the close resemblance with T1 slope in terms of correlation with those parameters. Both, upper and lower C7 slope correlated strongly with T1 slope and showed similar relationship with cervical balance parameters as T1 slope. Therefore, C7 slope could potentially substitute T1 slope, especially upper C7 slope due to the good visibility. 3.

  14. SirT1—A Sensor for Monitoring Self-Renewal and Aging Process in Retinal Stem Cells

    Directory of Open Access Journals (Sweden)

    Chi-Hsien Peng

    2010-06-01

    Full Text Available Retinal stem cells bear potency of proliferation, self-renewal, and differentiation into many retinal cells. Utilizing appropriate sensors one can effectively detect the self-renewal and aging process abilities. Silencing information regulator (SirT1, a member of the sirtuin family, is a NAD-dependent histone deacetylase and an essential mediator for longevity in normal cells by calorie restriction. We firstly investigate the SirT1 mRNA expression in retinal stem cells from rats and 19 human eyes of different ages. Results revealed that SirT1 expression was significantly decreased in in vivo aged eyes, associated with poor self-renewal abilities. Additionally, SirT1 mRNA levels were dose-dependently increased in resveratrol- treated retinal stem cells. The expression of SirT1 on oxidative stress-induced damage was significantly decreased, negatively correlated with the level of intracellular reactive oxygen species production. Treatment with resveratrol could effectively further reduce oxidative stress induced by H2O2 treatment in retinal stem cells. Importantly, the anti-oxidant effects of resveratrol in H2O2-treated retinal stem cells were significantly abolished by knockdown of SirT1 expression (sh-SirT1. SirT1 expression provides a feasible sensor in assessing self-renewal and aging process in retinal stem cells. Resveratrol can prevent reactive oxygen species-induced damages via increased retinal SirT1 expression.

  15. Overall Structural Design of Changsha IFC T1 Tower%长沙国金中心 T1塔楼总体结构设计

    Institute of Scientific and Technical Information of China (English)

    黄良

    2015-01-01

    Building height of the Changsha IFC T1 tower is 452 m,and its structural height is 440.45 m. Overground floor number is 92.Beside the structural height,the super high-rise tower exist some other transfinite problems such as inclined column transferring.Structural system of the tower and structural countermeasure to tackle transfinite problem are introduced.Obtaining value method for wind load and seismic action of the structure is put forward.Problem of foundation type selection is discussed.Main structural index of the tower is presented;elastic analysis results can satisfy demands of structural experts and Chinese code.Construction simulation analysis considering the non-load effect of the structure demonstrators that vertical deformation of the column and shear wall has little effect on strength of belt truss and outriggers.Shear wall of the tower is in a state of overall compression under middle seism.Elastic-plastic time-history analysis manifests that drift of the tower under rare earthquake load satisfy Chinese code requirements;overall structure is mostly in an elastic state.%长沙国金中心 T1塔楼建筑高度452 m,结构高度440.45 m,地上共92层;塔楼还存在斜柱转换、高位梁托柱转换等超限问题。论述了塔楼采用的结构体系及针对超限的相关结构对策;介绍了风荷载及地震作用的取值方法;阐述了塔楼基础的选型问题;归纳了塔楼弹性分析的主要结构指标,计算结果能够满足规范和超限审查专家的要求。考虑非荷载效应的塔楼施工模拟分析表明,巨柱与核心筒、巨柱与角柱等之间的竖向变形差对伸臂桁架及环带桁架的影响很小。塔楼核心筒剪力墙在中震下总体处于受压状态。弹塑性时程分析显示,罕遇地震下塔楼的位移满足规范要求,结构总体处于弹性状态,证明了结构的安全性。

  16. Simultaneous Imaging of CBF Change and BOLD with Saturation-Recovery-T1 Method.

    Science.gov (United States)

    Wang, Xiao; Zhu, Xiao-Hong; Zhang, Yi; Chen, Wei

    2015-01-01

    A neuroimaging technique based on the saturation-recovery (SR)-T1 MRI method was applied for simultaneously imaging blood oxygenation level dependence (BOLD) contrast and cerebral blood flow change (ΔCBF), which is determined by CBF-sensitive T1 relaxation rate change (ΔR1CBF). This technique was validated by quantitatively examining the relationships among ΔR1CBF, ΔCBF, BOLD and relative CBF change (rCBF), which was simultaneously measured by laser Doppler flowmetry under global ischemia and hypercapnia conditions, respectively, in the rat brain. It was found that during ischemia, BOLD decreased 23.1±2.8% in the cortical area; ΔR1CBF decreased 0.020±0.004s-1 corresponding to a ΔCBF decrease of 1.07±0.24 ml/g/min and 89.5±1.8% CBF reduction (n=5), resulting in a baseline CBF value (=1.18 ml/g/min) consistent with the literature reports. The CBF change quantification based on temperature corrected ΔR1CBF had a better accuracy than apparent R1 change (ΔR1app); nevertheless, ΔR1app without temperature correction still provides a good approximation for quantifying CBF change since perfusion dominates the evolution of the longitudinal relaxation rate (R1app). In contrast to the excellent consistency between ΔCBF and rCBF measured during and after ischemia, the BOLD change during the post-ischemia period was temporally disassociated with ΔCBF, indicating distinct CBF and BOLD responses. Similar results were also observed for the hypercapnia study. The overall results demonstrate that the SR-T1 MRI method is effective for noninvasive and quantitative imaging of both ΔCBF and BOLD associated with physiological and/or pathological changes.

  17. Simultaneous Imaging of CBF Change and BOLD with Saturation-Recovery-T1 Method.

    Directory of Open Access Journals (Sweden)

    Xiao Wang

    Full Text Available A neuroimaging technique based on the saturation-recovery (SR-T1 MRI method was applied for simultaneously imaging blood oxygenation level dependence (BOLD contrast and cerebral blood flow change (ΔCBF, which is determined by CBF-sensitive T1 relaxation rate change (ΔR1CBF. This technique was validated by quantitatively examining the relationships among ΔR1CBF, ΔCBF, BOLD and relative CBF change (rCBF, which was simultaneously measured by laser Doppler flowmetry under global ischemia and hypercapnia conditions, respectively, in the rat brain. It was found that during ischemia, BOLD decreased 23.1±2.8% in the cortical area; ΔR1CBF decreased 0.020±0.004s-1 corresponding to a ΔCBF decrease of 1.07±0.24 ml/g/min and 89.5±1.8% CBF reduction (n=5, resulting in a baseline CBF value (=1.18 ml/g/min consistent with the literature reports. The CBF change quantification based on temperature corrected ΔR1CBF had a better accuracy than apparent R1 change (ΔR1app; nevertheless, ΔR1app without temperature correction still provides a good approximation for quantifying CBF change since perfusion dominates the evolution of the longitudinal relaxation rate (R1app. In contrast to the excellent consistency between ΔCBF and rCBF measured during and after ischemia, the BOLD change during the post-ischemia period was temporally disassociated with ΔCBF, indicating distinct CBF and BOLD responses. Similar results were also observed for the hypercapnia study. The overall results demonstrate that the SR-T1 MRI method is effective for noninvasive and quantitative imaging of both ΔCBF and BOLD associated with physiological and/or pathological changes.

  18. HLA and autoimmune diseases: Type 1 diabetes (T1D) as an example.

    Science.gov (United States)

    Gorodezky, Clara; Alaez, Carmen; Murguía, Andrea; Rodríguez, Araceli; Balladares, Sandra; Vazquez, Miriam; Flores, Hilario; Robles, Carlos

    2006-03-01

    Autoimmune diseases need to be considered at a genetic and mechanistic level. T1D is an autoimmune, chronic, multifactorial and polygenic disease characterized by the destruction of the pancreatic beta-cells associated with long term dysfunction of several organs and tissues. Mechanisms of susceptibility include epi-genetic and post-transcriptional effects that regulate transmission and expression of the inherited genes. The HLA complex, constitutes the most relevant region contributing 50% of the inherited risk for T1D. An additional 17 genes with variable but small effects have been described. In non-Caucasians, the presence of E-DRbeta1-74 and/or D-DRbeta1-57 are relevant in predisposition. The "Diabetogenic haplotypes" in Mexicans were DRB1*0301-DQA1*0501-DQB1*0201 (OR = 21.4); DRB1*0405-DQA1-*0301-DQB1*0302 (OR = 44.5) and the same DQA1/DQB1 with DRB1*0404/*0401 conferring lower risk, increasing (OR = 61.3) with an early age at onset and a heterozygote DR3/DR4 genotype. In most populations, the absence of D-57 and the presence of R-52 are important to the susceptibility, but in Hispanics, all DR4s (including the protective DRB1*0403/*0407/*0411) are in linkage disequilibrium with DQA1/DQB1 susceptibility alleles. Thus, susceptibility alleles in Latin American Mestizos are of Mediterranean ancestry whereas protective alleles are of Amerindian origin. In this review, we discuss the complexity of T1D and some aspects of prevention/intervention based on immunogenetics.

  19. Prognostic impact of ReTURB in high grade T1 primary bladder cancer

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    Roberto Sanseverino

    2016-07-01

    Full Text Available Purpose: To evaluate whether pathological outcomes of ReTURB have a prognostic impact on recurrence and progression of primitive T1HG bladder cancer. Material and methods: Patients affected by primitive T1HG TCC of bladder underwent restaging TURB (ReTURB. Patients with muscle invasive disease at ReTURB underwent radical cystectomy; those with non-muscle invasive residual (NMI-RT and those with no residual tumour (NRT received an intravesical BCG therapy. We compared recurrence and progression in NMIRT patients and NRT patients at restaging TURB. Patients were followed every 3-6 months with cystoscopy and urine cytology. Results: 212 patients were enrolled in the study. At ReTURB, residual cancer was detected in 92 of 196 (46.9% valuable patients: 14.3% of these were upstaged to T2. At follow up of 26.3 ± 22.8 months, there were differences in recurrence and progression rates between NRT and NMIRT patients: 26.9% and 45.3% (p < 0.001, 10.6% and 23.4% (p 0.03, respectively. Recurrence-free and progression-free survivals were significantly higher in NRT compared to NMIRT patients: 73.1% and 54.7% (p < 0.001, 89.4% and 76.6 (p 0.03, respectively. Conclusions: ReTURB allows to identify a considerable number of residual and understaged cancer. Patients with NMIRT on ReTURB have worse prognosis than those with NRT in terms of recurrence and progression free survival. These outcomes seem to suggest a prognostic impact of findings on ReTURB that could be a valid tool in management of high grade T1 TCC.

  20. Short treatment time and excellent treatment outcome in accelerated hyperfractionated radiotherapy for T1 glottic cancer.

    Science.gov (United States)

    Tamaki, Yukihisa; Hieda, Yoko; Yoshida, Rika; Yoshizako, Takeshi; Fuchiwaki, Takafumi; Aoi, Noriaki; Sekihara, Kazumasa; Kitajima, Kazuhiro; Kawauchi, Hideyuki; Kitagaki, Hajime; Sasaki, Ryohei; Inomata, Taisuke

    2015-11-01

    Accelerated hyperfractionated radiotherapy was performed as treatment for patients with T1 glottic cancer, and its utility was evaluated based on treatment outcomes and adverse effects. Fifty-eight men who had undergone radiotherapy were retrospectively reviewed. Tumor classification was Tis in 4 patients, T1a in 38, and T1b in 16. Histological examination revealed squamous cell carcinoma in 55 patients. Travel time from home to hospital was 0-1 hour for 24 patients, 1-2 hours for 9, and >2 hours for 25. Laser vaporization was performed prior to radiotherapy in 38 patients, and 19 patients received concurrent chemotherapy with an agent such as S-1. Patients were irradiated twice daily using an irradiation container. Most patients received a dose of 1.5 Gy/fraction up to a total of 60 Gy. The median overall treatment time was 30 days, with a median observation period of 59.6 months. A complete response was observed in all patients. The 5-year overall survival, disease-free survival, and local control rates were 97.2%, 93.2%, and 97.8%, respectively. Although grade 3 pharyngeal mucositis was observed in 2 patients, there were no other grade 3 or higher acute adverse events. As late toxicity, grade 2 laryngeal edema and grade 1 laryngeal hemorrhage were observed in 1 patient each, but no serious events such as laryngeal necrosis or laryngeal stenosis were observed. In conclusion, this treatment method brings excellent outcome and will substantially reduce the treatment duration among patients who need to stay at nearby hotels while undergoing treatment at hospitals in rural areas.

  1. Novel free-hand T1 pedicle screw method: Review of 44 consecutive cases

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    Mark A Rivkin

    2014-01-01

    Full Text Available Summary of Background Data: Multilevel posterior cervical instrumented fusions are becoming more prevalent in current practice. Biomechanical characteristics of the cervicothoracic junction may necessitate extending the construct to upper thoracic segments. However, fixation in upper thoracic spine can be technically demanding owing to transitional anatomy while suboptimal placement facilitates vascular and neurologic complications. Thoracic instrumentation methods include free-hand, fluoroscopic guidance, and CT-based image guidance. However, fluoroscopy of upper thoracic spine is challenging secondary to vertebral geometry and patient positioning, while image-guided systems present substantial financial commitment and are not readily available at most centers. Additionally, imaging modalities increase radiation exposure to the patient and surgeon while potentially lengthening surgical time. Materials and Methods: Retrospective review of 44 consecutive patients undergoing a cervicothoracic fusion by a single surgeon using the novel free-hand T1 pedicle screw technique between June 2009 and November 2012. A starting point medial and cephalad to classic entry as well as new trajectory were utilized. No imaging modalities were employed during screw insertion. Postoperative CT scans were obtained on day 1. Screw accuracy was independently evaluated according to the Heary classification. Results: In total, 87 pedicle screws placed were at T1. Grade 1 placement occurred in 72 (82.8% screws, Grade 2 in 4 (4.6% screws and Grade 3 in 9 (10.3% screws. All Grade 2 and 3 breaches were <2 mm except one Grade 3 screw breaching 2-4 mm laterally. Only two screws (2.3% were noted to be Grade 4, both breaching medially by less than 2 mm. No new neurological deficits or returns to operating room took place postoperatively. Conclusions: This modification of the traditional starting point and trajectory at T1 is safe and effective. It attenuates additional bone

  2. Site of initial diabetes education does not affect metabolic outcomes in children with T1DM.

    Science.gov (United States)

    Tonyushkina, Ksenia N; Visintainer, Paul F; Jasinski, Christopher F; Wadzinski, Thomas L; Allen, Holley F

    2014-03-01

    To determine the difference in metabolic outcomes at 1 and 2 yr post type 1 diabetes mellitus (T1DM) diagnosis in children depending on the site of initial diabetes education: inpatient, vs. outpatient, vs. mixed locations. A retrospective chart review was performed for all patients with new onset antibody positive T1DM, aged 1-18 yr old, diagnosed in 2004-2009, and followed for at least 1 yr in a diabetes program at a tertiary academic health care center. Patients were divided into three groups based on the site of initial diabetes education: inpatient, outpatient, and mixed locations. The primary outcome was A1c at 1 and 2 yr. We enrolled 238 children (133 boys), mean (± SD) age 9.9 (± 4.1). A1c levels did not differ among inpatient, outpatient, and mixed location groups at 1 and 2 yr post diagnosis (p = 0.85 and p = 0.69, respectively) and the long-acting insulin doses were similar at 1 and 2 yr (p = 0.18 and p = 0.15, respectively). There was no difference in the number of acute diabetes complications between the groups. At 1 yr, 21.8% of outpatient-educated children were on insulin pump therapy in contrast to 14.7% of inpatient and 2.7% of mixed educated groups (p = 0.04). Families of children with new onset T1DM can be successfully and safely educated in a clinic setting. An 'education' admission for a medically stable patient is not necessary most of the time, however, clinical judgment and careful assessment of the family's coping and learning capabilities are important when determining the site of education. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  3. Anti-correlation between longevity gene SirT1 and Notch signaling in ascending aorta biopsies from patients with bicuspid aortic valve disease.

    Science.gov (United States)

    Sciacca, Sergio; Pilato, Michele; Mazzoccoli, Gianluigi; Pazienza, Valerio; Vinciguerra, Manlio

    2013-03-01

    About 1-2% of the population present with bicuspid aortic valves (BAV), a defect of the aortic valve resulting in the formation of two leaflets instead of three. This disease leads to an abnormal aorta, altered in strength and size, which in turn is a high risk factor for potentially lethal events such as aortic dissection and aneurysm formation. BAV is inheritable, with a demonstrated association with Notch1, a member of the Notch intercellular signaling pathway that is implicated in various cardiovascular disorders. Sirtuin 1 (SirT1) is a protein deacetylase of the sirtuin family, whose activation appears beneficial for cardiac diseases. A recent study has shown that SirT1 can limit Notch signaling in model systems of vascular growth. If a concomitant dysregulation in Notch and SirT1 signaling pathways can cause the phenotypic form of human BAV is unknown. To address this issue, we analyzed human ascending aorta biopsies from BAV and control patients obtained at the time of cardiac surgery. RNA and proteins were extracted from formalin-fixed and paraffin-embedded specimens, and quantitative real-time PCR and immunoblotting were used to determine the expression of sirtuins and members of the Notch family of proteins. We found a significant increase in SirT1 expression that correlates with a decreased expression of the Notch signaling effectors detected. We put forward the idea that an altered interaction between SirT1 and Notch signaling could participate in BAV pathogenesis and that these molecules could be used as potential clinical markers.

  4. Hyperintense basal ganglia lesions on T1-weighted MR images in asymptomatic patients with hepatic dysfunction

    Energy Technology Data Exchange (ETDEWEB)

    Saatci, I. [Dept. of Radiology, Hacettepe Univ. Hospital, Ankara (Turkey); Cila, A. [Dept. of Radiology, Hacettepe Univ. Hospital, Ankara (Turkey); Dincer, F.F. [Dept. of Radiology, Hacettepe Univ. Hospital, Ankara (Turkey)

    1995-12-31

    Cranial MRI findings in four patients who had hepatic dysfunction, including one with sole hepatic form of Wilson`s disease, were reported. The MR examinations revealed bilateral, symmetric hyperintensity in the globus pallidus, subthalamic nuclei and mesencephalon on T1-weighted images with no corresponding abnormality on T2-weighted sequences. The basal ganglia were normal on CT examinations in all patients. None of the patients had the clinical findings of hepatic encephalopathy. The MR findings in our patients did not correlate with the degree or duration of hepatic dysfunction. (orig.)

  5. Marrow signal mimicking tumor on MRI T1-weighted imaging after neoadjuvant chemotherapy in extremity osteosarcomas

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    Zhiping Deng

    2017-03-01

    Conclusions: Neoadjuvant chemotherapy for extremity osteosarcoma can result in a variety of changes of the MRI appearance of tumor and adjacent bone and marrow. Areas of signal change beyond the tumor that represent marrow conversion and not tumor progression appear on T1 weighted imaging to be lower in signal than subcutaneous fat and higher in signal than muscle. Recognizing the existence of the effect of neoadjuvant chemotherapy on the MR appearance of the tumor and surrounding bone and myeloid elements is important so as to plan for oncological sound tumor resections while avoiding resecting more normal bone than necessary.

  6. Non-enhanced T1-weighted liver vessel imaging at 7 Tesla.

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    Anja Fischer

    Full Text Available OBJECTIVES: Aim of the study was to assess the feasibility and to compare three non-enhanced T1-weighted (w sequences for liver vessel imaging at 7 Tesla (T. MATERIAL AND METHODS: 12 healthy volunteers were examined on a 7 T whole-body MR-system. The following non-enhanced sequences were acquired: T1w 2D FLASH, T1w 3D FLASH and Time of flight (TOF-MRA. Qualitative image analysis was performed by two radiologists including over all image quality as well as vessel delineation of the liver arteries, liver veins and portal vein and the presence of artifacts using a five-point scale (5 = excellent vessel delineation to 1 = non-diagnostic. Contrast ratios (CR, SNR und CNR of the above named vessels in correlation to adjacent liver tissue were calculated for quantitative assessment. For statistical analysis, a Wilcoxon Rank Test was applied. RESULTS: All three sequences provided a homogenous hyperintense delineation of the assessed liver vessels. Qualitative image analysis demonstrated the superiority of TOF-MRA, providing best overall image quality (TOF 4.17, 2D FLASH 3.42, 3D FLASH 3.46; p<0.01 as well as highest image quality values for all analyzed liver vessel segments. TOF-MRA was least impaired by B1 inhomogeneity (4.13 and susceptibility artifacts (4.63 out of all three sequences (p<0.01. Quantitative image analysis confirmed the superiority of TOF MRA showing significant higher CR values for all liver vessels (e.g. right hepatic artery TOF 0.47, 2D FLASH 0.09, 3D FLASH 0.11 with p = 0.02 and 0.01, respectively. Providing the lowest standard deviation in noise, TOF showed highest values for SNR and CNR. CONCLUSIONS: Non-enhanced T1w imaging in general and TOF MRA in particular, appear to be promising techniques for high quality non-enhanced liver vessel assessment at 7 T.

  7. Hydrogels incorporating GdDOTA: towards highly efficient dual T1/T2 MRI contrast agents.

    Science.gov (United States)

    Courant, Thomas; Roullin, Valérie Gaëlle; Cadiou, Cyril; Callewaert, Maïté; Andry, Marie Christine; Portefaix, Christophe; Hoeffel, Christine; de Goltstein, Marie Christine; Port, Marc; Laurent, Sophie; Elst, Luce Vander; Muller, Robert; Molinari, Michaël; Chuburu, Françoise

    2012-09-03

    Do not tumble dry: Gadolinium-DOTA encapsulated into polysaccharide nanoparticles (GdDOTA NPs) exhibited high relaxivity (r(1) =101.7 s(-1) mM(-1) per Gd(3+) ion at 37 °C and 20 MHz). This high relaxation rate is due to efficient Gd loading, reduced tumbling of the Gd complex, and the hydrogel nature of the nanoparticles. The efficacy of the nanoparticles as a T(1)/T(2) dual-mode contrast agent was studied in C6 cells.

  8. NOTCH2 is neither rearranged nor mutated in t(1;19 positive oligodendrogliomas.

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    Magdalena Benetkiewicz

    Full Text Available The combined deletion of 1p and 19q chromosomal arms is frequent in oligodendrogliomas (OD and has recently been shown to be mediated by an unbalanced t(1;19 translocation. Recent studies of 1p/19q co-deleted OD suggest that the NOTCH2 gene is implicated in oligodendrocyte differentiation and may be involved in this rearrangement. The objective of the present study was to analyze the NOTCH2 locus either as a chromosomal translocation locus that may be altered by the 1p/19q recurrent rearrangement or as a gene that may be inactivated by a two hit process. We performed an array-CGH analysis of 15 ODs presenting 1p/19q co-deletion using a high-density oligonucleotide microarray spanning 1p and 19q pericentromeric regions with 377 bp average probe spacing. We showed that the 1p deletion extends to the centromere of chromosome 1 and includes the entire NOTCH2 gene. No internal rearrangement of this gene was observed. This strongly suggests that the t(1;19 translocation does not lead to an abnormal NOTCH2 structure. The analysis of the entire NOTCH2 coding sequence was performed in four cases and did not reveal any mutation therefore indicating that NOTCH2 does not harbor genetic characteristics of a tumor suppressor gene. Finally, the detailed analysis of chromosome 19 pericentromeric region led to the identification of two breakpoint clusters at 19p12 and 19q11-12. Interestingly, these two regions share a large stretch of homology. Together with previous observations of similarities between chromosome 1 and 19 alphoid sequences, this suggests that the t(1;19 translocation arises from complex intra and interchromosomal rearrangements.This is the first comprehensive deletion mapping by high density oligo-array of the 1p/19q co-deletion in oligodendroglioma tumors using a methodological approach superior to others previously applied. As such this paper provides clear evidence that the NOTCH2 gene is not physically rearranged by t(1;19 translocation of

  9. CMR Imaging With Rapid Visual T1 Assessment Predicts Mortality in Patients Suspected of Cardiac Amyloidosis

    Science.gov (United States)

    White, James A.; Kim, Han W.; Shah, Dipan; Fine, Nowell; Kim, Ki-Young; Wendell, David C.; Al-Jaroudi, Wael; Parker, Michele; Patel, Manesh; Gwadry-Sridhar, Femida; Judd, Robert M.; Kim, Raymond J.

    2014-01-01

    OBJECTIVES This study tested the diagnostic and prognostic utility of a rapid, visual T1 assessment method for identification of cardiac amyloidosis (CA) in a “real-life” referral population undergoing cardiac magnetic resonance for suspected CA. BACKGROUND In patients with confirmed CA, delayed-enhancement cardiac magnetic resonance (DE-CMR) frequently shows a diffuse, global hyperenhancement (HE) pattern. However, imaging is often technically challenging, and the prognostic significance of diffuse HE is unclear. METHODS Ninety consecutive patients referred for suspected CA and 64 hypertensive patients with left ventricular hypertrophy (LVH) were prospectively enrolled and underwent a modified DE-CMR protocol. After gadolinium administration a method for rapid, visual T1 assessment was used to identify the presence of diffuse HE during the scan, allowing immediate optimization of settings for the conventional DE-CMR that followed. The primary endpoint was all-cause mortality. RESULTS Among patients with suspected CA, 66% (59 of 90) demonstrated HE, with 81% (48 of 59) of these meeting pre-specified visual T1 assessment criteria for diffuse HE. Among hypertensive LVH patients, 6% (4 of 64) had HE, with none having diffuse HE. During 29 months of follow-up (interquartile range: 12 to 44 months), there were 50 (56%) deaths in patients with suspected CA and 4 (6%) in patients with hypertensive LVH. Multivariable analysis demonstrated that the presence of diffuse HE was the most important predictor of death in the group with suspected CA (hazard ratio: 5.5, 95% confidence interval: 2.7 to 11.0; p < 0.0001) and in the population as a whole (hazard ratio: 6.0, 95% confidence interval 3.0 to 12.1; p < 0.0001). Among 25 patients with myocardial histology obtained during follow-up, the sensitivity, specificity, and accuracy of diffuse HE in the diagnosis of CA were 93%, 70%, and 84%, respectively. CONCLUSIONS Among patients suspected of CA, the presence of diffuse HE by

  10. Comparison of spoiled gradient echo and steady-state free-precession imaging for native myocardial T1 mapping using the slice-interleaved T1 mapping (STONE) sequence.

    Science.gov (United States)

    Jang, Jihye; Bellm, Steven; Roujol, Sébastien; Basha, Tamer A; Nezafat, Maryam; Kato, Shingo; Weingärtner, Sebastian; Nezafat, Reza

    2016-10-01

    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. A slice-interleaved T1 mapping (STONE) sequence with SSFP readout (STONE-SSFP) has been recently proposed for native myocardial T1 mapping, which allows longer recovery of magnetization (>8 R-R) after each inversion pulse. In this study, we hypothesize that a longer recovery allows higher SNR and enables native myocardial T1 mapping using STONE with GRE imaging readout (STONE-GRE) at 1.5T. Numerical simulations and phantom and in vivo imaging were performed to compare the performance of STONE-GRE and STONE-SSFP for native myocardial T1 mapping at 1.5T. In numerical simulations, STONE-SSFP shows sensitivity to both T2 and off resonance. Despite the insensitivity of GRE imaging to T2 , STONE-GRE remains sensitive to T2 due to the dependence of the inversion pulse performance on T2 . In the phantom study, STONE-GRE had inferior accuracy and precision and similar repeatability as compared with STONE-SSFP. In in vivo studies, STONE-GRE and STONE-SSFP had similar myocardial native T1 times, precisions, repeatabilities and subjective T1 map qualities. Despite the lower SNR of the GRE imaging readout compared with SSFP, STONE-GRE provides similar native myocardial T1 measurements, precision, repeatability, and subjective image quality when compared with STONE-SSFP at 1.5T.

  11. Murine breast carcinoma 4T1 cells are more sensitive to atranorin than normal epithelial NMuMG cells in vitro: Anticancer and hepatoprotective effects of atranorin in vivo.

    Science.gov (United States)

    Solár, Peter; Hrčková, Gabriela; Koptašíková, Lenka; Velebný, Samuel; Solárová, Zuzana; Bačkor, Martin

    2016-04-25

    The aim of this study was to evaluate the anticancer effect of atranorin (ATR) on murine 4T1 breast carcinoma cells and compare its sensitivity with normal mammary epithelial NMuMG cells in vitro. Anti-tumor and hepatoprotective activity of ATR-therapy was examined on mouse model of 4T1-induced cancer disease. ATR significantly reduced clonogenic ability of carcinoma 4T1 cells at the concentration of 75 μM, but clonogenicity of normal NMuMG cells was not affected by any of ATR concentrations tested. Moreover, flow cytometric and BrdU incorporation analysis did not confirm the inhibited entry into S-phase of the cell cyle after ATR incubation, and on the contrary, it induced apoptosis associated with the activation of caspase-3 and PARP cleavage in 4T1 cells. Although ATR did not cause any significant changes in Bcl-xL protein expression in NMuMG cells, an apparent depletion of Bcl-xL protein in 4T1 cells after 48 h ATR therapy was confirmed. Based on this result as well as the result of the total cell number decline, we can conclude that 4T1 cells are more sensitive to ATR therapy than NMuMG cells. ATR administration resulted in significantly longer survival time of BALB/c mice inoculated with 4T1 cells, what was associated with reduced tumor size and the higher numbers of apoptotic 4T1 cells. No differences were recorded in the number of BrdU-positive tumor cells between ATR-treated group and controls. Results indicate that ATR has rather proapoptotic than antiproliferative effect on 4T1 cells in vitro and in vivo and normal NMuMG cells are less sensitive to ATR. Furthermore, our studies revealed protective effect of ATR against oxidative stress in the livers of the tumor-bearing mice.

  12. Under which conditions does T1 difficulty affect T2 performance in the attentional blink?

    DEFF Research Database (Denmark)

    Nielsen, Simon; Petersen, Anders; Andersen, Tobias

    When two visual targets (T1 & T2) are presented in rapid succession, performance of T2 suffers up to 900 ms. One theory of this attentional blink (Raymond, Shapiro, & Arnell, 1992) propose that T1 and T2 compete for limited processing resources (Chun & Potter, 1995), and predict that prolonging...

  13. In vivo measurements of T1 relaxation times of 31P-metabolites in human skeletal muscle

    DEFF Research Database (Denmark)

    Thomsen, C; Jensen, K E; Henriksen, O

    1989-01-01

    The T1 relaxation times were estimated for 31P-metabolites in human skeletal muscle. Five healthy volunteers were examined in a 1.5 Tesla wholebody imaging system using an inversion recovery pulse sequence. The calculated T1 relaxation times ranged from 5.517 sec for phosphocreatine to 3.603 sec...

  14. Enrofloxacin and Probiotic Lactobacilli Influence PepT1 and LEAP-2 mRNA Expression in Poultry

    NARCIS (Netherlands)

    Pavlova, Ivelina; Milanova, Aneliya; Danova, Svetla; Fink-Gremmels, Johanna|info:eu-repo/dai/nl/119949997

    2016-01-01

    Expression of peptide transporter 1 (PepT1) and liver-expressed antimicrobial peptide 2 (LEAP-2) in chickens can be influenced by food deprivation, pathological conditions and drug administration. Effect of three putative probiotic Lactobacillus strains and enrofloxacin on the expression of PepT1

  15. PKC-Dependent GlyT1 Ubiquitination Occurs Independent of Phosphorylation: Inespecificity in Lysine Selection for Ubiquitination.

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    Susana P Barrera

    Full Text Available Neurotransmitter transporter ubiquitination is emerging as the main mechanism for endocytosis and sorting of cargo into lysosomes. In this study, we demonstrate PKC-dependent ubiquitination of three different isoforms of the glycine transporter 1 (GlyT1. Incubation of cells expressing transporter with the PKC activator phorbol ester induced a dramatic, time-dependent increase in GlyT1 ubiquitination, followed by accumulation of GlyT1 in EEA1 positive early endosomes. This occurred via a mechanism that was abolished by inhibition of PKC. GlyT1 endocytosis was confirmed in both retinal sections and primary cultures of mouse amacrine neurons. Replacement of only all lysines in the N-and C-termini to arginines prevented ubiquitination and endocytosis, displaying redundancy in the mechanism of ubiquitination. Interestingly, a 40-50% reduction in glycine uptake was detected in phorbol-ester stimulated cells expressing the WT-GlyT1, whereas no significant change was for the mutant protein, demonstrating that endocytosis participates in the reduction of uptake. Consistent with previous findings for the dopamine transporter DAT, ubiquitination of GlyT1 tails functions as sorting signal to deliver transporter into the lysosome and removal of ubiquitination sites dramatically attenuated the rate of GlyT1 degradation. Finally, we showed for the first time that PKC-dependent GlyT1 phosphorylation was not affected by removal of ubiquitination sites, suggesting separate PKC-dependent signaling events for these posttranslational modifications.

  16. Enrofloxacin and Probiotic Lactobacilli Influence PepT1 and LEAP-2 mRNA Expression in Poultry

    NARCIS (Netherlands)

    Pavlova, Ivelina; Milanova, Aneliya; Danova, Svetla; Fink-Gremmels, Johanna|info:eu-repo/dai/nl/119949997

    2016-01-01

    Expression of peptide transporter 1 (PepT1) and liver-expressed antimicrobial peptide 2 (LEAP-2) in chickens can be influenced by food deprivation, pathological conditions and drug administration. Effect of three putative probiotic Lactobacillus strains and enrofloxacin on the expression of PepT1 an

  17. Potential energy surfaces of short polyenes in the state T1 : analysis of time resolved resonance Raman spectra

    NARCIS (Netherlands)

    Orlandi, G.; Negri, F.; Wilbrandt, R.; Langkilde, F.W.; Brouwer, A.M.

    1993-01-01

    The analysis of T1 resonance Raman spectra of some conjugated compounds is discussed making use of semiempirical quantum chemical calculations. Information obtained about T1 potential energy curve indicates that in short polyenes the perpendicular form is roughly degenerate with the trans isomer. Pr

  18. Synthesis of hypoallergenic derivatives of the major allergen Fag t 1 from tartary buckwheat via sequence restructuring.

    Science.gov (United States)

    Yang, Zhenhuang; Li, Yuying; Li, Chen; Wang, Zhuanhua

    2012-08-01

    Fag t 1, a legumin-type protein, is the major allergen in tartary buckwheat. In the current study, three recombinant derivatives of Fag t 1, designated as Fag t 1-rs1, Fag t 1-rs2, and Fag t 1-rs3, were constructed via rational design and genetic engineering. However, because of the loss of their native-like folds, the Fag t 1 derivatives failed to bind IgE, and their allergenic activities were reduced. The recombinant hypoallergenic variants are promising vaccine candidates for specific immunotherapy of buckwheat allergy. The unfolding of the Fag t 1 structure reduced its high resistance to gastrointestinal proteolysis and strongly reduced its IgE reactivity. The derivatives showed a more than 90% reduction in allergenic activity compared with rFag t 1. These results suggest that the structure-dependent stability of 11S seed storage proteins is directly related to digestive stability and allergenic potential. Therefore, the destruction of the native conformation is the appropriate strategy to reduce the allergenicity of the cupin family food allergens.

  19. Caffeine intake inverts the effect of adenosine on myocardial perfusion during stress as measured by T1 mapping

    NARCIS (Netherlands)

    Kuijpers, Dirkjan; Prakken, Niek H.; Vliegenthart, Rozemarijn; van Dijkman, Paul R. M.; van der Harst, Pim; Oudkerk, Matthijs

    2016-01-01

    Caffeine intake before adenosine stress myocardial perfusion imaging may cause false negative findings. We hypothesized that the antagonistic effect of caffeine can be measured by T1 relaxation times in rest and adenosine stress cardiac magnetic resonance imaging (CMR), as T1 mapping techniques are

  20. NMR-based metabolomics and breath studies show lipid and protein catabolism during low dose chronic T(1)AM treatment.

    Science.gov (United States)

    Haviland, J A; Reiland, H; Butz, D E; Tonelli, M; Porter, W P; Zucchi, R; Scanlan, T S; Chiellini, G; Assadi-Porter, F M

    2013-12-01

    3-Iodothyronamine (T1 AM), an analog of thyroid hormone, is a recently discovered fast-acting endogenous metabolite. Single high-dose treatments of T1 AM have produced rapid short-term effects, including a reduction of body temperature, bradycardia, and hyperglycemia in mice. The effect of daily low doses of T1 AM (10 mg/kg) for 8 days on weight loss and metabolism in spontaneously overweight mice was monitored. The experiments were repeated twice (n = 4). Nuclear magnetic resonance (NMR) spectroscopy of plasma and real-time analysis of exhaled (13) CO2 in breath by cavity ring down spectroscopy (CRDS) were used to detect T1 AM-induced lipolysis. CRDS detected increased lipolysis in breath shortly after T1 AM administration that was associated with a significant weight loss but independent of food consumption. NMR spectroscopy revealed alterations in key metabolites in serum: valine, glycine, and 3-hydroxybutyrate, suggesting that the subchronic effects of T1 AM include both lipolysis and protein breakdown. After discontinuation of T1 AM treatment, mice regained only 1.8% of the lost weight in the following 2 weeks, indicating lasting effects of T1 AM on weight maintenance. CRDS in combination with NMR and (13) C-metabolic tracing constitute a powerful method of investigation in obesity studies for identifying in vivo biochemical pathway shifts and unanticipated debilitating side effects. Copyright © 2013 The Obesity Society.

  1. A preliminary study of MR T1 mapping for detection of left ventricular myocardial fibrosis in hypertrophic cardiomyopathy

    Institute of Scientific and Technical Information of China (English)

    陆敏杰

    2013-01-01

    Objective To investigate the diagnostic values of T1mapping imaging for evaluating myocardial fibrosis in patients with hypertrophic cardiomyopathy (HCM) .Methods Forty-eight subjects with HCM and 18 healthy volunteers underwent conventional late gadolinium enhancement (LGE) MR imaging and T1mapping imaging.

  2. MRI T1ρ值的测量在早期肝硬化诊断中的应用研究%Application research of magnetic resonance T1ρ value measurement in the diagnosis of early liver cirrhosis

    Institute of Scientific and Technical Information of China (English)

    王雪; 刘松国; 韩广; 孟祥福

    2016-01-01

    Objective:To explore the utility of magnetic resonance T1ρ-weighted imaging (T1ρWI) in the diagnosis of early liver cirrhosis. Methods:40 cases of early cirrhosis patients (observation subjects) and 25 healthy physical examination volunteers (control subjects) were performed with conventional MRI,then T1ρWI was acquired from four breath-hold scans with different spin-lock times (10,20,40 and 80 ms). The T1ρ values of the observation subjects and healthy control subjects were measured and compared respectively. The T1ρ values of CPS A and CPS B in the observation subjects were compared with healthy control subjects respectively. The correlation between T1ρ value and the subjects age was analyzed in the healthy control subjects. Re-sults:The T1ρ value of observation subjects (56.0 ms±4.0 ms) was significantly higher than the T1ρ value of healthy control subjects (49.7 ms±3.5 ms). The T1ρ values of CPS A and CPS B in the observation subjects were significantly difference,com-pared with healthy control subjects respectively (P<0.05). There was no significant correlation between the age of healthy sub-jects and liver T1ρ value in the control subjects (r=0.18,P=0.58). Conclusion:T1ρ value in quantitative diagnosis of early liver cirrhosis has high sensitivity and repeatability.%目的:探讨MRI T1ρWI对早期肝硬化的诊断价值。方法:40例早期肝硬化患者(观察组)和25例健康体检者(对照组)均行常规MRI扫描,并根据不同的自旋锁定时间(10、20、40和80 ms)行4次屏气T1ρ扫描。分别测量出观察组和对照组肝脏的T1ρ值并进行对比;在对照组内分析受检者的年龄与肝脏T1ρ值的相关性。结果:观察组平均T1ρ值(56.0±4.0)ms明显高于对照组的(49.7±3.5)ms。观察组Child-Pugh肝功能改良分级A和B级的T1ρ值分别与对照组比较,差异均有统计学意义(均P<0.05)。对照组年龄与肝脏T1ρ值无明显相关性(r=0.18,P=0.58)。结论:T

  3. High-resolution in vivo Wistar rodent brain atlas based on T1 weighted image

    Science.gov (United States)

    Huang, Su; Lu, Zhongkang; Huang, Weimin; Seramani, Sankar; Ramasamy, Boominathan; Sekar, Sakthivel; Guan, Cuntai; Bhakoo, Kishore

    2016-03-01

    Image based atlases for rats brain have a significant impact on pre-clinical research. In this project we acquired T1-weighted images from Wistar rodent brains with fine 59μm isotropical resolution for generation of the atlas template image. By applying post-process procedures using a semi-automatic brain extraction method, we delineated the brain tissues from source data. Furthermore, we applied a symmetric group-wise normalization method to generate an optimized template of T1 image of rodent brain, then aligned our template to the Waxholm Space. In addition, we defined several simple and explicit landmarks to corresponding our template with the well known Paxinos stereotaxic reference system. Anchoring at the origin of the Waxholm Space, we applied piece-wise linear transformation method to map the voxels of the template into the coordinates system in Paxinos' stereotoxic coordinates to facilitate the labelling task. We also cross-referenced our data with both published rodent brain atlas and image atlases available online, methodologically labelling the template to produce a Wistar brain atlas identifying more than 130 structures. Particular attention was paid to the cortex and cerebellum, as these areas encompass the most researched aspects of brain functions. Moreover, we adopted the structure hierarchy and naming nomenclature common to various atlases, so that the names and hierarchy structure presented in the atlas are readily recognised for easy use. It is believed the atlas will present a useful tool in rodent brain functional and pharmaceutical studies.

  4. Mini Transsternal Approach to the Anterior High Thoracic Spine (T1–T4 Vertebrae

    Directory of Open Access Journals (Sweden)

    Christian Brogna

    2016-01-01

    Full Text Available Purpose. The anterior high thoracic spine is one of the most complex segments to be accessed surgically due to anatomical constraints and transitional characteristics. We describe in detail the mini transsternal approach to metastatic, infective, traumatic, and degenerative pathologies of T1 to T4 vertebral bodies. We analyse our surgical series, indications, and outcomes. Methods. Over a 5-year period 18 consecutive patients with thoracic myelopathy due to metastatic, infective, traumatic, and degenerative pathologies with T1 to T4 vertebral bodies involvement received a mini transsternal approach with intraoperative monitoring. Frankel scoring system was used to grade the neurological status. Results. Mean follow-up was 40 months. 78% patients improved in Frankel grade after surgery and 22% patients remained unchanged. Average operation time was 210 minutes. There were no intraoperative complications. One patient developed postoperative pneumonia successfully treated with antibiotics. Conclusion. The mini transsternal is a safe approach for infective, metastatic, traumatic, and degenerative lesions affecting the anterior high thoracic spine and the only one allowing an early and direct visualisation of the anterior theca. This approach overcomes the anatomical constraints of this region and provides adequate room for optimal reconstruction and preservation of spinal alignment in the cervicothoracic transition zone with good functional patient outcomes.

  5. Quantitative analysis of voice quality after radiation therapy for stage T1a glottic carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Joon Kyoo; Chung, Woong Gi [Chonnam National University Hospital, Gwangju (Korea, Republic of)

    2005-03-15

    To evaluate the voices of irradiated patients with early glottic carcinoma and to compare these with the voices of healthy volunteers. The voice samples (sustained vowel) of seventeen male patients who had been irradiated for T1a glottic squamous carcinoma at least 1 year prior to the study were analyzed with objective voice analyzer (acoustic voice analysis, aerodynamic test, and videostroboscopic analysis) and compared with those of a normal group of twenty age-and sex-matched volunteers. Average fundamental frequency, jitter, shimmer, and noise-to-harmonic ratio were obtained for acoustic voice analysis. Maximal phonation time, mean flow rate, intensity, subglottic pressure, glottal resistance, glottal efficiency, and glottal power were obtained for aerodynamic test. The irradiated group presented higher values of shimmer in acoustic voice analysis. There was no significant difference between two groups in other parameters. In this study all the objective voice parameters except shimmer were not significantly different between the irradiated group and the control group. These results suggest that the voice quality is minimally affected by radiation therapy for T1a glottic carcinoma.

  6. Photogeneration of superparaelectric large polarons in dielectrics with soft anharmonic T1u phonons

    Science.gov (United States)

    Nasu, Keiichiro

    2003-05-01

    In connection with the recent experiments on photoenhancements of the electronic conductivity and the quasistatic electric susceptibility of SrTiO3, we theoretically study global versus local parity violation of a photogenerated electron in this dielectric. The photogenerated electron, being quite itinerant in the 3d band of Ti, is assumed to couple weakly but quadratically with soft-anharmonic T1u phonons in this dielectric. The electron is also assumed to couple strongly but linearly to the breathing (A1g) type high energy phonons. We will show that these two types of electron-phonon (e-p) couplings result in two types of polarons, a “superparaelectric large polaron” with a quasiglobal parity violation, and an “off-center type self-trapped polaron” with only a local parity violation. These two states are shown to be separated by an adiabatic potential barrier, if these e-p couplings are short in their force ranges. Without the T1u phonon, these two states reduce to the well-known large polaron and the self-trapped one, both of which have even parities. We will also show that this superparaelectric large polaron enhances both the electronic conductivity and the quasistatic electric susceptibility, in qualitative agreements with the experiments.

  7. Photoinitiated H2CO unimolecular decomposition: Accessing H+HCO products via S0 and T1 pathways

    Science.gov (United States)

    Valachovic, L. R.; Tuchler, M. F.; Dulligan, M.; Droz-Georget, Th.; Zyrianov, M.; Kolessov, A.; Reisler, H.; Wittig, C.

    2000-02-01

    The photoinitiated unimolecular decomposition of formaldehyde via the H+HCO radical channel has been examined at energies where the S0 and T1 pathways both participate. The barrierless S0 pathway has a loose transition state (which tightens somewhat with increasing energy), while the T1 pathway involves a barrier and therefore a tight transition state. The product state distributions which derive from the S0 and T1 pathways differ qualitatively, thereby providing a means of discerning the respective S0 and T1 contributions. Energies in excess of the H+HCO threshold have been examined throughout the range 1103⩽E†⩽2654 cm-1 by using two complementary experimental techniques; ion imaging and high-n Rydberg time-of-flight spectroscopy. It was found that S0 dominates at the low end of the energy range. Here, T1 participation is sporadic, presumably due to poor coupling between zeroth-order S1 levels and T1 reactive resonances. These T1 resonances have small decay widths because they lie below the T1 barrier. Alternatively, at the high end of the energy range, the T1 pathway dominates, though a modest S0 contribution is always present. The transition from S0 dominance to T1 dominance occurs over a broad energy range. The most reliable value for the T1 barrier (1920±210 cm-1) is given by the recent ab initio calculations of Yamaguchi et al. It lies near the center of the region where the transition from S0 dominance to T1 dominance takes place. Thus, the present results are consistent with the best theoretical calculations as well as the earlier study of Chuang et al., which bracketed the T1 barrier energy between 1020 and 2100 cm-1 above the H+HCO threshold. The main contribution of the present work is an experimental demonstration of the transition from S0 to T1 dominance, highlighting the sporadic nature of this competition.

  8. MR imaging of hematopoietic regions in bone marrow of aplastic anemia. Diagnostic usefulness of opposed phase T1-weighted images

    Energy Technology Data Exchange (ETDEWEB)

    Amano, Yasuo; Tanabe, Yoshihiro; Amano, Maki; Kumazaki, Tatsuo [Nippon Medical School, Tokyo (Japan)

    1996-01-01

    The signal intensity of hematopoietic regions in the marrow of aplastic anemia were investigated on opposed phase T1-weighted images (op-T1WI) with a 0.5-Tesla MR unit. Hematopoietic regions were classified into two groups: low intensity hematopoietic areas (LH) isointense to normal marrow and high intensity hematopoietic regions (HH) with higher intensity than normal marrow on op-T1WI. The signal intensity of LH was significantly lower than that of HH on STIR. LH converted into HH with improvement of laboratory data after therapy, whereas HH decreased with impairment of data. HH were hyperintense to cerebrospinal fluid on op-T1WI. These results indicated that the signal intensity of hematopoietic regions on op-T1WI reflected the cellularity in these regions and that aplastic anemia included hypercellular regions relative to normal marrow. (author).

  9. Modulation of sweet taste by umami compounds via sweet taste receptor subunit hT1R2.

    Directory of Open Access Journals (Sweden)

    Jaewon Shim

    Full Text Available Although the five basic taste qualities-sweet, sour, bitter, salty and umami-can be recognized by the respective gustatory system, interactions between these taste qualities are often experienced when food is consumed. Specifically, the umami taste has been investigated in terms of whether it enhances or reduces the other taste modalities. These studies, however, are based on individual perception and not on a molecular level. In this study we investigated umami-sweet taste interactions using umami compounds including monosodium glutamate (MSG, 5'-mononucleotides and glutamyl-dipeptides, glutamate-glutamate (Glu-Glu and glutamate-aspartic acid (Glu-Asp, in human sweet taste receptor hT1R2/hT1R3-expressing cells. The sensitivity of sucrose to hT1R2/hT1R3 was significantly attenuated by MSG and umami active peptides but not by umami active nucleotides. Inhibition of sweet receptor activation by MSG and glutamyl peptides is obvious when sweet receptors are activated by sweeteners that target the extracellular domain (ECD of T1R2, such as sucrose and acesulfame K, but not by cyclamate, which interact with the T1R3 transmembrane domain (TMD. Application of umami compounds with lactisole, inhibitory drugs that target T1R3, exerted a more severe inhibitory effect. The inhibition was also observed with F778A sweet receptor mutant, which have the defect in function of T1R3 TMD. These results suggest that umami peptides affect sweet taste receptors and this interaction prevents sweet receptor agonists from binding to the T1R2 ECD in an allosteric manner, not to the T1R3. This is the first report to define the interaction between umami and sweet taste receptors.

  10. T1-Weighted MR imaging of liver tumor by gadolinium-encapsulated glycol chitosan nanoparticles without non-specific toxicity in normal tissues

    Science.gov (United States)

    Na, Jin Hee; Lee, Sangmin; Koo, Heebeom; Han, Hyounkoo; Lee, Kyung Eun; Han, Seung Jin; Choi, Seung Hong; Kim, Hyuncheol; Lee, Seulki; Kwon, Ick Chan; Choi, Kuiwon; Kim, Kwangmeyung

    2016-05-01

    Herein, we have synthesized Gd(iii)-encapsulated glycol chitosan nanoparticles (Gd(iii)-CNPs) for tumor-targeted T1-weighted magnetic resonance (MR) imaging. The T1 contrast agent, Gd(iii), was successfully encapsulated into 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA)-modified CNPs to form stable Gd(iii)-encapsulated CNPs (Gd(iii)-CNPs) with an average particle size of approximately 280 nm. The stable nanoparticle structure of Gd(iii)-CNPs is beneficial for liver tumor accumulation by the enhanced permeation and retention (EPR) effect. Moreover, the amine groups on the surface of Gd(iii)-CNPs could be protonated and could induce fast cellular uptake at acidic pH in tumor tissue. To assay the tumor-targeting ability of Cy5.5-labeled Gd(iii)-CNPs, near-infrared fluorescence (NIRF) imaging and MR imaging were used in a liver tumor model as well as a subcutaneous tumor model. Cy5.5-labeled Gd(iii)-CNPs generated highly intense fluorescence and T1 MR signals in tumor tissues after intravenous injection, while DOTAREM®, the commercialized control MR contrast agent, showed very low tumor-targeting efficiency on MR images. Furthermore, damaged tissues were found in the livers and kidneys of mice injected with DOTAREM®, but there were no obvious adverse effects with Gd(iii)-CNPs. Taken together, these results demonstrate the superiority of Gd(iii)-CNPs as a tumor-targeting T1 MR agent.Herein, we have synthesized Gd(iii)-encapsulated glycol chitosan nanoparticles (Gd(iii)-CNPs) for tumor-targeted T1-weighted magnetic resonance (MR) imaging. The T1 contrast agent, Gd(iii), was successfully encapsulated into 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA)-modified CNPs to form stable Gd(iii)-encapsulated CNPs (Gd(iii)-CNPs) with an average particle size of approximately 280 nm. The stable nanoparticle structure of Gd(iii)-CNPs is beneficial for liver tumor accumulation by the enhanced permeation and retention (EPR) effect. Moreover, the

  11. Measurement of blood-brain barrier permeability with t1-weighted dynamic contrast-enhanced MRI in brain tumors: a comparative study with two different algorithms.

    Science.gov (United States)

    Bergamino, Maurizio; Saitta, Laura; Barletta, Laura; Bonzano, Laura; Mancardi, Giovanni Luigi; Castellan, Lucio; Ravetti, Jean Louis; Roccatagliata, Luca

    2013-01-01

    The purpose of this study was to assess the feasibility of measuring different permeability parameters with T1-weighted dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI) in order to investigate the blood brain-barrier permeability associated with different brain tumors. The Patlak algorithm and the extended Tofts-Kety model were used to this aim. Twenty-five adult patients with tumors of different histological grades were enrolled in this study. MRI examinations were performed at 1.5 T. Multiflip angle, fast low-angle shot, and axial 3D T1-weighted images were acquired to calculate T1 maps, followed by a DCE acquisition. A region of interest was placed within the tumor of each patient to calculate the mean value of different permeability parameters. Differences in permeability measurements were found between different tumor grades, with higher histological grades characterized by higher permeability values. A significant difference in transfer constant (K (trans)) values was found between the two methods on high-grade tumors; however, both techniques revealed a significant correlation between the histological grade of tumors and their K (trans) values. Our results suggest that DCE acquisition is feasible in patients with brain tumors and that K (trans) maps can be easily obtained by these two algorithms, even if the theoretical model adopted could affect the final results.

  12. Assessment of T2- and T1-weighted MRI brain lesion load in patients with subcortical vascular encephalopathy

    Energy Technology Data Exchange (ETDEWEB)

    Gass, A.; Oster, M.; Cohen, S.; Daffertshofer, M.; Schwartz, A.; Hennerici, M.G. [Neurologische Universitaetsklinik, Klinikum Mannheim der Universitaet Heidelberg (Germany)

    1998-08-01

    Previous cross-sectional studies in patients with subcortical vascular encephalopathy (SVE) have shown little or no correlation between brain lesion load and clinical disability, which could be due to the low specificity of T2-weighted MRI. Recent studies have indicated that T1-weighted MRI may be more specific than T2-weighted MRI for severe tissue destruction. We studied 37 patients with a diagnosis of SVE and 11 normal controls with standardised T1- and T2-weighted MRI. All patients underwent detailed clinical assessment including a neuropsychological test battery and computerised gait analysis. Both the T2- and T1-weighted total MRI lesion loads different between patients and controls different, particularly T1. The ratio of T2-/T1-weighted lesion load was lower in controls than in patients. There was no overall correlation of T1- or T2-weighted lesion load with clinical disability, but group comparison of patients with severe and mild clinical deficits showed different lesion loads. We suggest that T1- and T2-weighted MRI lesion loads demonstrate relevant structural abnormality in patients with SVE. (orig.) With 1 fig., 25 refs.

  13. mIGF-1/JNK1/SirT1 signaling confers protection against oxidative stress in the heart.

    Science.gov (United States)

    Vinciguerra, Manlio; Santini, Maria Paola; Martinez, Conception; Pazienza, Valerio; Claycomb, William C; Giuliani, Alessandro; Rosenthal, Nadia

    2012-02-01

    Oxidative stress contributes to the pathogenesis of aging-associated heart failure. Among various signaling pathways mediating oxidative stress, the NAD(+) -dependent protein deacetylase SirT1 has been implicated in the protection of heart muscle. Expression of a locally acting insulin-like growth factor-1 (IGF-1) propeptide (mIGF-1) helps the heart to recover from infarct and enhances SirT1 expression in cardiomyocytes (CM) in vitro, exerting protection from hypertrophic and oxidative stresses. To study the role of mIGF-1/SirT1 signaling in vivo, we generated cardiac-specific mIGF-1 transgenic mice in which SirT1 was depleted from adult CM in a tamoxifen-inducible and conditional fashion. Analysis of these mice confirmed that mIGF-1-induced SirT1 activity is necessary to protect the heart from paraquat (PQ)-induced oxidative stress and lethality. In cultured CM, mIGF-1 increases SirT1 expression through a c-Jun NH(2)-terminal protein kinase 1 (JNK1)-dependent signaling mechanism. Thus, mIGF-1 protects the heart from oxidative stress via SirT1/JNK1 activity, suggesting new avenues for cardiac therapy during aging and heart failure.

  14. T1 mapping in myocarditis - headway to a new era for cardiovascular magnetic resonance.

    Science.gov (United States)

    Hinojar, Rocio; Nagel, Eike; Puntmann, Valentina O

    2015-01-01

    Myocarditis is a major cause of cardiac morbidity and mortality, particularly in young patients. A spectrum of challenges besets this condition, from establishing the diagnosis to effective treatment. Endomyocardial biopsy remains the diagnostic gold standard, despite its invasiveness, low diagnostic yield and a paucity of consequential management pathways. Cardiac magnetic resonance by Lake Louise criteria has contested to become the non-invasive diagnostic alternative by providing confirmation of disease. The advent of T1 mapping now allows a high diagnostic accuracy in confirmation and exclusion of disease, discrimination of stages and activity of disease. Alongside the research into the mechanisms and potential therapeutic targets, cardiac magnetic resonance confidently claims a prime role within a modern diagnostic pathway in clinically stable patients with suspected myocarditis.

  15. Intracranial lesions with high signal intensity on T1-weighted MR images – review of pathologies

    Science.gov (United States)

    Zimny, Anna; Zińska, Lidia; Bladowska, Joanna; Neska-Matuszewska, Małgorzata; Sąsiadek, Marek

    2013-01-01

    Summary In the article we present pathological intracranial substances and lesions, which produce high signal intensity on T1-weighted MR images. Six groups of substances are discussed: 1. Gadolinium – based contrast agents, 2.hemoglobin degradation products (intra- and extra-cellular methemoglobin), 3. lipid-containing lesions (lipoma, dermoid cyst, implanted fatty materials, laminar cortical necrosis), 4. substances with high concentration of proteins (colloid cyst, craniopharyngioma, Rathke’s cleft cyst, ectopic posterior pituitary gland), 5. melanin (metastatic melanoma), 6. lesions containing mineral substances such as: calcium (calcifications, Fahr’s disease), copper (Wilson’s disease) and manganese (hepatic encephalopathy, manganese intoxication in intravenous drug abusers). Appropriate interpretation of signal intensity as well as analysis of location of lesions and clinical symptoms enables planning of further diagnostics and, in many cases, establishing the final diagnosis based on MR examination. PMID:24505222

  16. Effect of biasing on plasma rotation in the edge of IR-T1 Tokamak

    Energy Technology Data Exchange (ETDEWEB)

    Mohammadi, S.; Ghoranneviss, M.; Arvin, R.; Gheydi, M.; Nikmohammadi, A. [Plasma physics Research Center, Science and Research Branch, Islamic Azad University, P.O.Box: 14665-768 Tehran (Iran, Islamic Republic of); Khorshid, P.; Bolourian, H. [Department of Physics, Islamic Azad University, Mashhad Branch, Mashhad (Iran, Islamic Republic of)

    2011-07-01

    Full text of publication follows: Electrode biasing experiments were carried out on the IR-T1 Tokamak. The effects of radial electric field (Er) on plasma fluid velocity and magnetic island rotation investigated by a Mach/Langmuir electric probe and an array of 12 Mirnov coils. The Results have shown a change in the fluid velocity during biasing regime. References: [1] Van Oost G. et al. 2001 Czech. J. of Phys. 51 957; [2] Effect of Plasma Biasing on Suppression of Electrostatic Fluctuation in the Edge Region of STP-3(M) Reversed Field Pinch J. Phys. Soc. Jpn. 74 (2005) pp.605-612; [3] Weynants R. R. and Van Oost G. 1993 Plasma Phys. Contr. Fusion 35 B177. (authors)

  17. Vibrio cholerae bacteriophage CP-T1: characterization of bacteriophage DNA and restriction analysis.

    Science.gov (United States)

    Guidolin, A; Morelli, G; Kamke, M; Manning, P A

    1984-01-01

    Temperature bacteriophage CP-T1 of Vibrio cholerae has a capsid that is 45 nm in diameter, a contractile tail 65 nm long and 9.5 nm wide, and a baseplate with several spikes or short tail fibers. The linear double-stranded DNA is 43.5 +/- 1.4 kilobases long, and the phage genome is both terminally redundant and partially circularly permuted. The extent of terminal redundancy is ca. 4%, and circular permutation is up to ca. 44%. Circular restriction maps have been constructed for the enzymes HindIII, EcoRI, BamHI, and PstI. By restriction endonuclease and heteroduplex analyses of phage DNA, the presence and location of a site (pac) at which packaging of phage DNA is initiated was established. Images PMID:6328035

  18. Vibrio cholerae bacteriophage CP-T1: characterization of bacteriophage DNA and restriction analysis.

    Science.gov (United States)

    Guidolin, A; Morelli, G; Kamke, M; Manning, P A

    1984-07-01

    Temperature bacteriophage CP-T1 of Vibrio cholerae has a capsid that is 45 nm in diameter, a contractile tail 65 nm long and 9.5 nm wide, and a baseplate with several spikes or short tail fibers. The linear double-stranded DNA is 43.5 +/- 1.4 kilobases long, and the phage genome is both terminally redundant and partially circularly permuted. The extent of terminal redundancy is ca. 4%, and circular permutation is up to ca. 44%. Circular restriction maps have been constructed for the enzymes HindIII, EcoRI, BamHI, and PstI. By restriction endonuclease and heteroduplex analyses of phage DNA, the presence and location of a site (pac) at which packaging of phage DNA is initiated was established.

  19. The data processing and analysis for the CE-5T1 GNSS experiment

    Science.gov (United States)

    Liu, Huicui; Cao, Jianfeng; Cheng, Xiao; Peng, Jing; Tang, Geshi

    2017-02-01

    In this paper the performance of a high sensitivity GPS/GLONASS receiver mounted on CE-5T1 Service Module is studied and the data received on the first Earth-lunar transfer orbit is processed and analyzed. At least four GLONASS satellites are visible for 46% of the data span while for 98% of the data span at least four GPS satellites are visible. GLONASS serves as a necessary supplement to GPS in real time positioning whenever less than four GPS satellites are tracked, and helps to optimize the observation geometry by reducing the Position Dilution of Precision (PDOP) values by up to 77%. However, noisier GLONASS pseudorange data should be properly weighted in order not to deteriorate the positioning accuracy. Studies indicate that when the inverse square of the pseudorange measurement error of each satellite is applied as the weight value, single point positioning (SPP) accuracy improves from 57.7 m (RMS) with GPS data alone to 44.6 m (RMS) with the addition of GLONASS data. Transmitter antenna Equivalent Isotropic Radiated Power (EIRP)s of all the four blocks of GPS satellites as well as GLONASS satellites are derived from the received C/N0 data and show significant variance in sidelobe power patterns. In general, the EIRP patterns of GPS Block IIR-M and GLONASS satellite antennas have a comparatively flat power level of around 10 dB W within the off-boresight angle range of 30-80° and roll off at the off-boresight angle of about 80°, offering deep space applications greater benefits than the other three blocks of GPS satellites. In addition, an interesting close encounter happens between CE-5T1 spacecraft and GLONASS satellite R06. Investigations indicate that the PDOP value increases up to 1.4 times and the SPP accuracy deteriorates by more than 142% if satellite R06 is excluded in the positioning computation.

  20. Magic angle effect plays a major role in both T1rho and T2 relaxation in articular cartilage.

    Science.gov (United States)

    Shao, H; Pauli, C; Li, S; Ma, Y; Tadros, A S; Kavanaugh, A; Chang, E Y; Tang, G; Du, J

    2017-02-01

    To investigate the effect of sample orientation on T1rho and T2 values of articular cartilage in histologically confirmed normal and abnormal regions using a whole-body 3T scanner. Eight human cadaveric patellae were evaluated using a 2D CPMG sequence for T2 measurement as well as a 2D spin-locking prepared spiral sequence and a 3D magnetization-prepared angle-modulated partitioned-k-space spoiled gradient echo snapshots (3D MAPSS) sequence for T1rho measurement. Each sample was imaged at six angles from 0° to 100° relative to the B0 field. T2 and T1rho values were measured for three regions (medial, apex and lateral) with three layers (10% superficial, 60% middle, 30% deep). Multiple histopathologically confirmed normal and abnormal regions were used to evaluate the angular dependence of T2 and T1rho relaxation in articular cartilage. Our study demonstrated a strong magic angle effect for T1rho and T2 relaxation in articular cartilage, especially in the deeper layers of cartilage. On average, T2 values were increased by 231.8% (72.2% for superficial, 237.6% for middle, and 187.9% for deep layers) while T1rho values were increased by 92% (31.7% for superficial, 69% for middle, and 140% for deep layers) near the magic angle. Both normal and abnormal cartilage showed similar T1rho and T2 magic angle effect. Changes in T1rho and T2 values due to the magic angle effect can be several times more than that caused by degeneration, and this may significantly complicate the clinical application of T1rho and T2 as an early surrogate marker for degeneration. Copyright © 2017 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.

  1. T1-mapping for assessment of ischemia-induced acute kidney injury and prediction of chronic kidney disease in mice

    Energy Technology Data Exchange (ETDEWEB)

    Hueper, Katja; Gutberlet, Marcel; Wacker, Frank; Hartung, Dagmar [Hannover Medical School, Department of Radiology, Hannover (Germany); Hannover Medical School, REBIRTH Cluster of Excellence, Hannover (Germany); Peperhove, Matti; Tewes, Susanne; Barrmeyer, Amelie [Hannover Medical School, Department of Radiology, Hannover (Germany); Rong, Song [Hannover Medical School, Department of Nephrology, Hannover (Germany); Zunyi Medical College, Laboratory of Organ Transplantation, Zunyi (China); Gerstenberg, Jessica; Haller, Herman; Gueler, Faikah [Hannover Medical School, Department of Nephrology, Hannover (Germany); Mengel, Michael [University of Alberta, Department of Laboratory Medicine and Pathology, Edmonton (Canada); Meier, Martin [Hannover Medical School, REBIRTH Cluster of Excellence, Hannover (Germany); Hannover Medical School, Institute for Animal Science, Hannover (Germany); Chen, Rongjun [Hannover Medical School, Department of Nephrology, Hannover (Germany); Zhejiang University, The Kidney Disease Center of the First Affiliated Hospital, Hangzhou (China)

    2014-09-15

    To investigate whether T1-mapping allows assessment of acute kidney injury (AKI) and prediction of chronic kidney disease (CKD) in mice. AKI was induced in C57Bl/6N mice by clamping of the right renal pedicle for 35 min (moderate AKI, n = 26) or 45 min (severe AKI, n = 23). Sham animals served as controls (n = 9). Renal histology was assessed in the acute (day 1 + day 7; d1 + d7) and chronic phase (d28) after AKI. Furthermore, longitudinal MRI-examinations (prior to until d28 after surgery) were performed using a 7-Tesla magnet. T1-maps were calculated from a fat-saturated echoplanar inversion recovery sequence, and mean and relative T1-relaxation times were determined. Renal histology showed severe tubular injury at d1 + d7 in both AKI groups, whereas, at d28, only animals with prolonged 45-min ischemia showed persistent signs of AKI. Following both AKI severities T1-values significantly increased and peaked at d7. T1-times in the contralateral kidney without AKI remained stable. At d7 relative T1-values in the outer stripe of the outer medulla were significantly higher after severe than after moderate AKI (138 ± 2 % vs. 121 ± 3 %, p = 0.001). T1-elevation persisted until d28 only after severe AKI. Already at d7 T1 in the outer stripe of the outer medulla correlated with kidney volume loss indicating CKD (r = 0.83). T1-mapping non-invasively detects AKI severity in mice and predicts further outcome. (orig.)

  2. Site-directed mutagenesis of Arginine282 suggests how protons and peptides are co-transported by rabbit PepT1.

    Science.gov (United States)

    Pieri, Myrtani; Hall, Dashiell; Price, Richard; Bailey, Patrick; Meredith, David

    2008-01-01

    The mammalian proton-coupled peptide transporter PepT1 is the major route of uptake for dietary nitrogen, as well as the oral absorption of a number of drugs, including beta-lactam antibiotics and angiotensin-converting enzyme inhibitors. Here we have used site-directed mutagenesis to investigate further the role of conserved charged residues in transmembrane domains. Mutation of rabbit PepT1 arginine282 (R282, transmembrane domain 7) to a positive (R282K) or physiologically titratable residue (R282H), resulted in a transporter with wild-type characteristics when expressed in Xenopus laevis oocytes. Neutral (R282A, R282Q) or negatively charged (R282D, R282E) substitutions gave a transporter that was not stimulated by external acidification (reducing pH(out) from 7.4 to 5.5) but transported at the same rate as the wild-type maximal rate (pH(out) 5.5); however, only the R282E mutation was unable to concentrate substrate above the extracellular level. All of the R282 mutants showed trans-stimulation of efflux comparable to the wild-type, except R282E-PepT1 which was faster. A conserved negatively charged residue, aspartate341 (D341) in transmembrane domain 8 was implicated in forming a charge pair with R282, as R282E/D341R- and R282D/D341R-PepT1 had wild-type transporter characteristics. Despite their differences in ability to accumulate substrate, both R282E- and R282D-PepT1 showed an increased charge:peptide stoichiometry over the wild-type 1:1 ratio for the neutral dipeptide Gly-l-Gln, measured using two-electrode voltage clamp. This extra charge movement was linked to substrate transport, as 4-aminobenzoic acid, which binds but is not translocated, did not induce membrane potential depolarisation in R282E-expressing oocytes. A model is proposed for the substrate binding/translocation process in PepT1.

  3. SU-D-303-03: Impact of Uncertainty in T1 Measurements On Quantification of Dynamic Contrast Enhanced MRI

    Energy Technology Data Exchange (ETDEWEB)

    Aryal, M; Cao, Y [The University of Michigan, Ann Arbor, MI (United States)

    2015-06-15

    Purpose: Quantification of dynamic contrast enhanced (DCE) MRI requires native longitudinal relaxation time (T1) measurement. This study aimed to assess uncertainty in T1 measurements using two different methods. Methods and Materials: Brain MRI scans were performed on a 3T scanner in 9 patients who had low grade/benign tumors and partial brain radiotherapy without chemotherapy at pre-RT, week-3 during RT (wk-3), end-RT, and 1, 6 and 18 months after RT. T1-weighted images were acquired using gradient echo sequences with 1) 2 different flip angles (50 and 150), and 2) 5 variable TRs (100–2000ms). After creating quantitative T1 maps, average T1 was calculated in regions of interest (ROI), which were distant from tumors and received a total of accumulated radiation doses < 5 Gy at wk-3. ROIs included left and right normal Putamen and Thalamus (gray matter: GM), and frontal and parietal white matter (WM). Since there were no significant or even a trend of T1 changes from pre-RT to wk-3 in these ROIs, a relative repeatability coefficient (RC) of T1 as a measure of uncertainty was estimated in each ROI using the data pre-RT and at wk-3. The individual T1 changes at later time points were evaluated compared to the estimated RCs. Results: The 2-flip angle method produced small RCs in GM (9.7–11.7%) but large RCs in WM (12.2–13.6%) compared to the saturation-recovery (SR) method (11.0–17.7% for GM and 7.5–11.2% for WM). More than 81% of individual T1 changes were within T1 uncertainty ranges defined by RCs. Conclusion: Our study suggests that the impact of T1 uncertainty on physiological parameters derived from DCE MRI is not negligible. A short scan with 2 flip angles is able to achieve repeatability of T1 estimates similar to a long scan with 5 different TRs, and is desirable to be integrated in the DCE protocol. Present study was supported by National Institute of Health (NIH) under grant numbers; UO1 CA183848 and RO1 NS064973.

  4. Human cyclin T1 expression ameliorates a T-cell-specific transcriptional limitation for HIV in transgenic rats, but is not sufficient for a spreading infection of prototypic R5 HIV-1 strains ex vivo

    Directory of Open Access Journals (Sweden)

    Littman Dan R

    2009-01-01

    Full Text Available Abstract Background Cells derived from native rodents have limits at distinct steps of HIV replication. Rat primary CD4 T-cells, but not macrophages, display a profound transcriptional deficit that is ameliorated by transient trans-complementation with the human Tat-interacting protein Cyclin T1 (hCycT1. Results Here, we generated transgenic rats that selectively express hCycT1 in CD4 T-cells and macrophages. hCycT1 expression in rat T-cells boosted early HIV gene expression to levels approaching those in infected primary human T-cells. hCycT1 expression was necessary, but not sufficient, to enhance HIV transcription in T-cells from individual transgenic animals, indicating that endogenous cellular factors are critical co-regulators of HIV gene expression in rats. T-cells from hCD4/hCCR5/hCycT1-transgenic rats did not support productive infection of prototypic wild-type R5 HIV-1 strains ex vivo, suggesting one or more significant limitation in the late phase of the replication cycle in this primary rodent cell type. Remarkably, we identify a replication-competent HIV-1 GFP reporter strain (R7/3 YU-2 Env that displays characteristics of a spreading, primarily cell-to-cell-mediated infection in primary T-cells from hCD4/hCCR5-transgenic rats. Moreover, the replication of this recombinant HIV-1 strain was significantly enhanced by hCycT1 transgenesis. The viral determinants of this so far unique replicative ability are currently unknown. Conclusion Thus, hCycT1 expression is beneficial to de novo HIV infection in a transgenic rat model, but additional genetic manipulations of the host or virus are required to achieve full permissivity.

  5. Precision measurement of the half-life and branching ratio of the T=1/2 mirror $\\beta$-decay of $^{37}$K

    CERN Multimedia

    We propose to study the T=1/2 mirror $\\beta$-decay of $^{37}$K. Nuclear mirror $\\beta$-decay is a competitive means to test the electroweak model by means of the high-precision measurement of V$_{ud}$ element of the CKM quark mixing matrix. One key ingredient to obtain V$_{ud}$ is the force of the transition, Ft, which has to be determined with a relative precision below 10$^{−3}$. This quantity is related to the half-life T$_{1/2}$ of the decaying nucleus, the branching ratio BR for this decay and the mass difference between the mother and daughter nucleus (Q value). Another important feature is the mixing ratio $\\rho$ between the Fermi and the Gamow-Teller character of the transition. In most cases, $\\rho$ is the major contributor to the uncertainty on Ft. Available data concerning T$_{1/2}$ and BR of $^{37}$K suffer from a lack of precision that will be easily reduced by a dedicated experiment.

  6. Licoricidin, an Active Compound in the Hexane/Ethanol Extract of Glycyrrhiza uralensis, Inhibits Lung Metastasis of 4T1 Murine Mammary Carcinoma Cells

    Directory of Open Access Journals (Sweden)

    So Young Park

    2016-06-01

    Full Text Available Licorice extracts containing glycyrrhizin exhibit anti-carcinogenic properties. Because glycyrrhizin induces severe hypokalemia and hypertension, we prepared a hexane/ethanol extract of Glycyrrhiza uralensis (HEGU that lacks glycyrrhizin, and showed that HEGU induces apoptosis and G1 cell cycle arrest and inhibits migration of DU145 human prostate cancer cells. Our previous in vitro studies identified two active components in HEGU: isoangustone A, which induces apoptosis and G1 cycle arrest, and licoricidin, which inhibits metastasis. This study examined whether HEGU and licoricidin inhibit metastasis using the 4T1 mammary cancer model. Both HEGU and licoricidin treatment reduced pulmonary metastasis and the expression of CD45, CD31, HIF-1α, iNOS, COX-2, and VEGF-A in tumor tissues. Additionally, a decrease in protein expression of VEGF-R2, VEGF-C, VEGF-R3, and LYVE-1 was noted in tumor tissues of licoricidin-treated mice. Furthermore, the blood concentrations of MMP-9, ICAM-1, VCAM-1, and VEGF-A were decreased in HEGU-treated mice. In vitro 4T1 cell culture results showed that both HEGU and licoricidin inhibited cell migration, MMP-9 secretion, and VCAM expression. The present study demonstrates that the licoricidin in HEGU inhibits lung metastasis of 4T1 mammary carcinoma cells, which may be mediated via inhibition of cancer cell migration, tumor angiogenesis, and lymphangiogenesis.

  7. Isovector spin-singlet (T=1, S=0) and isoscalar spin-triplet (T=0, S=1) pairing interactions and spin-isospin response

    CERN Document Server

    Sagawa, H; Colo', G

    2015-01-01

    We review several experimental and theoretical advances that emphasise common aspects of the study of T=1 and T=0 pairing correlations in nuclei. We first discuss several empirical evidences of the special role played by the T=1 pairing interaction. In particular, we show the peculiar features of the nuclear pairing interaction in the low density regime, and possible outcomes such as the BCS-BEC crossover in nuclear matter and, in an analogous way, in loosely bound nuclei. We then move to the competition between T=1 and T=0 pairing correlations. The effect of such competition on the low-lying spectra is studied in N=Z odd-odd nuclei by using a three-body model; it is shown that the inversion of the 0+ and 1+ states near the ground state, and the strong magnetic dipole transitions between them, can be considered as a clear manifestation of strong T=0 pairing correlations in these nuclei. The effect of T=0 pairing correlations is also quite evident if one studies charge-changing transitions. The Gamow-Teller (G...

  8. Effects of GWAS-associated genetic variants on lncRNAs within IBD and T1D candidate loci

    DEFF Research Database (Denmark)

    Mirza, Aashiq H; Kaur, Simranjeet; Brorsson, Caroline A;

    2014-01-01

    Long non-coding RNAs are a new class of non-coding RNAs that are at the crosshairs in many human diseases such as cancers, cardiovascular disorders, inflammatory and autoimmune disease like Inflammatory Bowel Disease (IBD) and Type 1 Diabetes (T1D). Nearly 90% of the phenotype-associated single......, we systemically identified all annotated IBD and T1D loci-associated lncRNAs, and mapped nominally significant GWAS/ImmunoChip SNPs for IBD and T1D within these lncRNAs. Additionally, we identified tissue-specific cis-eQTLs, and strong linkage disequilibrium (LD) signals associated with these SNPs....... We explored sequence and structure based attributes of these lncRNAs, and also predicted the structural effects of mapped SNPs within them. We also identified lncRNAs in IBD and T1D that are under recent positive selection. Our analysis identified putative lncRNA secondary structure-disruptive SNPs...

  9. Confirmation of T1-Bright Vein of Galen Aneurysm Spontaneous Thrombosis by Subtraction Magnetic Resonance Venography: A Case Report

    Energy Technology Data Exchange (ETDEWEB)

    Irfan, M.; Lohman, B.; McKinney, A.M. (Dept. of Radiology/Neuroradiology, Univ. of Minnesota, Minneapolis, Minnesota (United States))

    2009-08-15

    Spontaneous thrombosis of a vein of Galen aneurysmal malformation (VOGM) is rare. We describe a 2-month-old patient with a patent VOGM and hydrocephalus, also confirmed patent at 6 months, but with subsequent lack of filling on pre-embolization catheter digital subtraction angiography (DSA) at 9 months' age. Due to the presence of T1- and T2-bright signal, noncontrast T1-weighted images (T1WI), T2-weighted images (T2WI), two-dimensional (2D) time-of-flight (TOF) magnetic resonance venography (MRV), and postcontrast T1WI were ambiguous for patency. However, subtracting the pre- from the postcontrast MRV images confirmed closure compared to subtracted images at 6 months' age. The factors contributing to thrombosis were likely a combination of a disproportionately small straight sinus, ventriculostomy, and contrast medium from DSA.

  10. [Ischemic stroke in a young woman of Turner syndrome with T1-weighted imaging-pulvinar sign].

    Science.gov (United States)

    Sangkyun, Ko; Kawano, Akiko; Yamanoi, Takahiko; Tokunaga, Keiko

    2014-01-01

    A 39-year-old woman developed right hemiparesis in a few days. Magnetic resonance images revealed cerebral infarction in the territory of the left lenticulostriate artery, and MR angiography showed severe stenosis of the middle and anterior cerebral arteries and moderate one of the vertebral arteries. Bilateral and symmetric T1 hyperintensity in the pulvinar (T1-weighted imaging-pulvinar sign; "T1 pulvinar sign") was detected, which is recognized as a key imaging of Fabry disease. The α-galactosidase A gene analysis, however, showed no mutation. Although specific physical symptoms were solely short stature and oligomenorrhea, the diagnosis of Turner syndrome was confirmed by the chromosome analysis which showed mosaicism of 45XO and 46X,r(X) (60%:40%). To our knowledge, this is the first report of Turner syndrome with "T1 pulvinar sign".

  11. Mapping pathological changes in brain structure by combining T1- and T2-weighted MR imaging data

    Energy Technology Data Exchange (ETDEWEB)

    Ganzetti, Marco; Mantini, Dante [ETH Zurich, Neural Control of Movement Laboratory, Department of Health Sciences and Technology, Zurich (Switzerland); University of Oxford, Department of Experimental Psychology, Oxford (United Kingdom); Wenderoth, Nicole [ETH Zurich, Neural Control of Movement Laboratory, Department of Health Sciences and Technology, Zurich (Switzerland); KU Leuven, Laboratory of Movement Control and Neuroplasticity, Faculty of Kinesiology and Rehabilitation Sciences, Leuven (Belgium)

    2015-09-15

    A workflow based on the ratio between standardized T1-weighted (T1-w) and T2-weighted (T2-w) MR images has been proposed as a new tool to study brain structure. This approach was previously used to map structural properties in the healthy brain. Here, we evaluate whether the T1-w/T2-w approach can support the assessment of structural impairments in the diseased brain. We use schizophrenia data to demonstrate the potential clinical utility of the technique. We analyzed T1-w and T2-w images of 36 schizophrenic patients and 35 age-matched controls. These were collected for the Function Biomedical Informatics Research Network (fBIRN) collaborative project, which had an IRB approval and followed the HIPAA guidelines. We computed T1-w/T2-w images for each individual and compared intensities in schizophrenic and control groups on a voxel-wise basis, as well as in regions of interest (ROIs). Our results revealed that the T1-w/T2-w image permits to discriminate brain regions showing group-level differences between patients and controls with greater accuracy than conventional T1-w and T2-w images. Both the ROIs and the voxel-wise analysis showed globally reduced gray and white matter values in patients compared to controls. Significantly reduced values were found in regions such as insula, primary auditory cortex, hippocampus, inferior longitudinal fasciculus, and inferior fronto-occipital fasciculus. Our findings were consistent with previous meta-analyses in schizophrenia corroborating the hypothesis of a potential ''disconnection'' syndrome in conjunction with structural alterations in local gray matter regions. Overall, our study suggested that the T1-w/T2-w technique permits to reliably map structural differences between the brains of patients and healthy individuals. (orig.)

  12. 7 Tesla quantitative hip MRI: T1, T2 and T2* mapping of hip cartilage in healthy volunteers

    Energy Technology Data Exchange (ETDEWEB)

    Lazik, Andrea; Theysohn, Jens M.; Geis, Christina [University Hospital Essen, Department of Diagnostic and Interventional Radiology and Neuroradiology, Essen (Germany); Johst, Soeren; Kraff, Oliver [University of Duisburg-Essen, Erwin L. Hahn Institute for Magnetic Resonance Imaging, Essen (Germany); Ladd, Mark E. [University Hospital Essen, Department of Diagnostic and Interventional Radiology and Neuroradiology, Essen (Germany); University of Duisburg-Essen, Erwin L. Hahn Institute for Magnetic Resonance Imaging, Essen (Germany); German Cancer Research Center (DKFZ), Medical Physics in Radiology, Heidelberg (Germany); Quick, Harald H. [University of Duisburg-Essen, Erwin L. Hahn Institute for Magnetic Resonance Imaging, Essen (Germany); University Hospital Essen, High Field and Hybrid MR Imaging, Essen (Germany)

    2016-05-15

    To evaluate the technical feasibility and applicability of quantitative MR techniques (delayed gadolinium-enhanced MRI of cartilage (dGEMRIC), T2 mapping, T2* mapping) at 7 T MRI for assessing hip cartilage. Hips of 11 healthy volunteers were examined at 7 T MRI with an 8-channel radiofrequency transmit/receive body coil using multi-echo sequences for T2 and T2* mapping and a dual flip angle gradient-echo sequence before (T1{sub 0}) and after intravenous contrast agent administration (T1{sub Gd}; 0.2 mmol/kg Gd-DTPA{sup 2-} followed by 0.5 h of walking and 0.5 h of rest) for dGEMRIC. Relaxation times of cartilage were measured manually in 10 regions of interest. Pearson's correlations between R1{sub delta} = 1/T1{sub Gd} - 1/T1{sub 0} and T1{sub Gd} and between T2 and T2* were calculated. Image quality and the delineation of acetabular and femoral cartilage in the relaxation time maps were evaluated using discrete rating scales. High correlations were found between R1{sub delta} and T1{sub Gd} and between T2 and T2* relaxation times (all p < 0.01). All techniques delivered diagnostic image quality, with best delineation of femoral and acetabular cartilage in the T2* maps (mean 3.2 out of a maximum of 4 points). T1, T2 and T2* mapping of hip cartilage with diagnostic image quality is feasible at 7 T. To perform dGEMRIC at 7 T, pre-contrast T1 mapping can be omitted. (orig.)

  13. Cardiovascular magnetic resonance by non contrast T1-mapping allows assessment of severity of injury in acute myocardial infarction

    Science.gov (United States)

    2012-01-01

    Background Current cardiovascular magnetic resonance (CMR) methods, such as late gadolinium enhancement (LGE) and oedema imaging (T2W) used to depict myocardial ischemia, have limitations. Novel quantitative T1-mapping techniques have the potential to further characterize the components of ischemic injury. In patients with myocardial infarction (MI) we sought to investigate whether state-of the art pre-contrast T1-mapping (1) detects acute myocardial injury, (2) allows for quantification of the severity of damage when compared to standard techniques such as LGE and T2W, and (3) has the ability to predict long term functional recovery. Methods 3T CMR including T2W, T1-mapping and LGE was performed in 41 patients [of these, 78% were ST elevation MI (STEMI)] with acute MI at 12-48 hour after chest pain onset and at 6 months (6M). Patients with STEMI underwent primary PCI prior to CMR. Assessment of acute regional wall motion abnormalities, acute segmental damaged fraction by T2W and LGE and mean segmental T1 values was performed on matching short axis slices. LGE and improvement in regional wall motion at 6M were also obtained. Results We found that the variability of T1 measurements was significantly lower compared to T2W and that, while the diagnostic performance of acute T1-mapping for detecting myocardial injury was at least as good as that of T2W-CMR in STEMI patients, it was superior to T2W imaging in NSTEMI. There was a significant relationship between the segmental damaged fraction assessed by either by LGE or T2W, and mean segmental T1 values (P myocardial damage. T1-mapping might become an important complementary technique to LGE and T2W for identification of reversible myocardial injury and prediction of functional recovery in acute MI. PMID:22309452

  14. Local IGF-1 isoform protects cardiomyocytes from hypertrophic and oxidative stresses via SirT1 activity.

    Science.gov (United States)

    Vinciguerra, Manlio; Santini, Maria Paola; Claycomb, William C; Ladurner, Andreas G; Rosenthal, Nadia

    2009-12-10

    Oxidative and hypertrophic stresses contribute to the pathogenesis of heart failure. Insulin-like growth factor-1 (IGF-1) is a peptide hormone with a complex post-transcriptional regulation, generating distinct isoforms. Locally acting IGF-1 isoform (mIGF-1) helps the heart to recover from toxic injury and from infarct. In the murine heart, moderate overexpression of the NAD(+)-dependent deacetylase SirT1 was reported to mitigate oxidative stress. SirT1 is known to promote lifespan extension and to protect from metabolic challenges. Circulating IGF-1 and SirT1 play antagonizing biological roles and share molecular targets in the heart, in turn affecting cardiomyocyte physiology. However, how different IGF-1 isoforms may impact SirT1 and affect cardiomyocyte function is unknown. Here we show that locally acting mIGF-1 increases SirT1 expression/activity, whereas circulating IGF-1 isoform does not affect it, in cultured HL-1 and neonatal cardiomyocytes. mIGF-1-induced SirT1 activity exerts protection against angiotensin II (Ang II)-triggered hypertrophy and against paraquat (PQ) and Ang II-induced oxidative stress. Conversely, circulating IGF-1 triggered itself oxidative stress and cardiomyocyte hypertrophy. Interestingly, potent cardio-protective genes (adiponectin, UCP-1 and MT-2) were increased specifically in mIGF-1-overexpressing cardiomyocytes, in a SirT1-dependent fashion. Thus, mIGF-1 protects cardiomyocytes from oxidative and hypertrophic stresses via SirT1 activity, and may represent a promising cardiac therapeutic.

  15. Stripe rust resistance and dough quality of new wheat - Dasypyrum villosum translocation lines T1DL•1V#3S and T1DS•1V#3L and the location of HMW-GS genes.

    Science.gov (United States)

    Zhao, W C; Gao, X; Dong, J; Zhao, Z J; Chen, Q G; Chen, L G; Shi, Y G; Li, X Y

    2015-07-17

    The transfer of agronomically useful genes from wild wheat species into cultivated wheat is one of the most effective approaches to improvement of wheat varieties. To evaluate the transfer of genes from Dasypyrum villosum into Triticum aestivum, wheat quality and disease resistance was evaluated in two new translocation lines, T1DL•1V#3S and T1DS•1V#3L. We examined the levels of stripe rust resistance and dough quality in the two lines, and identified and located the stripe rust resistant genes and high molecular weight glutenin subunit (HMW-GS) genes Glu-V1 of D. villosum. Compared to the Chinese Spring (CS) variety, T1DL•1V#3S plants showed moderate resistance to moderate susceptibility to the stripe rust races CYR33 and Su11-4. However, T1DS•1V#3L plants showed high resistance or immunity to these stripe rusts. The genes for resistance to stripe rust were located on 1VL of D. villosum. In comparison to CS, the dough from T1DS•1V#3L had a significantly shorter developing time (1.45 min) and stable time (1.0 min), a higher weakness in gluten strength (208.5 FU), and a lower farinograph quality index (18). T1DL•1V#3S had a significantly longer developing time (4.2 min) and stable time (5.25 min), a lower weakness in gluten strength (53 FU) and a higher farinograph quality index (78.5). We also found that T1DS•1V#3L had reduced gluten strength and dough quality compared to CS, but T1DL•1V#3S had increased gluten strength and dough quality. The results of SDS-PAGE analysis indicated that Glu-V1 of D. villosum was located on short arm 1VS and long arm 1VL. These results prove that the new translocation lines, T1DS•1V#3L and T1DS•1V#3L, have valuable stripe rust resistance and dough quality traits that will be important for improving wheat quality and resistance in future wheat breeding programs.

  16. Laparoscopic partial nephrectomy for T1a renal tumors is safe and feasible

    Institute of Scientific and Technical Information of China (English)

    WANG Hui; GAO Zhen-li; LIN Chun-hua; WU Ji-tao; WANG Lin; WANG Jian-ming; SUN De-kang; WANG Ke; YU Qing-xia

    2011-01-01

    Background Some patients with exophytic renal masses less than 4 cm and suboptimal renal function, or a solitary kidney and bilateral renal tumors are considered for laparoscopic partial nephrectomy (LPN), which is feasible for early-stage renal tumors, although it is still considered technically difficult and time consuming. Shortening the time of the operation and renal warm ischemia are required urgently. In this study, we report our initial experiences of LPN,especially with some improved surgical techniques. Methods Between July 2005 and October 2009, 74 patients with T1a renal tumor were treated by LPN, 39 using transperitoneal approach and 35 using retroperitoneal approach. In all cases, the tumor was removed with a margin of 0.5 cm. We compared glomerular filtration rate (GFR) preoperatively and postoperatively, and renal warm ischemia time between traditional ligature and Hem-o-lok methods. Results All operations were completed successfully, and there was no conversion to open surgery. Mean operation time was 76 minutes (range, 68-120), mean time of renal warm ischemia was 23 minutes (range, 15-32), and mean blood loss was 65 ml (range, 40-300). No hemorrhage or urine leak was observed in two cases with the collecting system sewn. Thirteen cases used Hem-o-lok to clamp the suture instead of traditional ligature, and mean time of renal warm ischemia was (16.5±2.3) minutes (range, 12-18). Mean postoperative hospital stay was 6.3 days (range, 5-12).Sixty-seven cases had renal clear cell carcinoma, six papillary renal cell carcinoma, and one renal collecting duct carcinoma. All the tumor margin specimens were negative. The mean follow-up was 30.6 months (range, 3-51), and no recurrence or metastasis was observed. Conclusions LPN for pT1 stage renal tumor was safe and feasible. Hem-o-lok instead of traditional ligature to clamp the suture when sewing the renal wound could shorten the warm ischemia time.

  17. Evaluation of MR imaging with T1 and T2* mapping for the determination of hepatic iron overload

    Energy Technology Data Exchange (ETDEWEB)

    Henninger, B.; Kremser, C.; Rauch, S.; Eder, R.; Schocke, M. [Innsbruck Medical University, Department of Radiology, Innsbruck (Austria); Zoller, H.; Finkenstedt, A. [Innsbruck Medical University, Department of Internal Medicine, Innsbruck (Austria); Michaely, H.J. [Medical Faculty Mannheim - Heidelberg University, Institute of Clinical Radiology and Nuclear Medicine, University Medical Center Mannheim, Mannheim (Germany)

    2012-11-15

    To evaluate MRI using T1 and T2* mapping sequences in patients with suspected hepatic iron overload (HIO). Twenty-five consecutive patients with clinically suspected HIO were retrospectively studied. All underwent MRI and liver biopsy. For the quantification of liver T2* values we used a fat-saturated multi-echo gradient echo sequence with 12 echoes (TR = 200 ms, TE = 0.99 ms + n x 1.41 ms, flip angle 20 ). T1 values were obtained using a fast T1 mapping sequence based on an inversion recovery snapshot FLASH sequence. Parameter maps were analysed using regions of interest. ROC analysis calculated cut-off points at 10.07 ms and 15.47 ms for T2* in the determination of HIO with accuracy 88 %/88 %, sensitivity 84 %/89.5 % and specificity 100 %/83 %. MRI correctly classified 20 patients (80 %). All patients with HIO only had decreased T1 and T2* relaxation times. There was a significant difference in T1 between patients with HIO only and patients with HIO and steatohepatitis (P = 0.018). MRI-based T2* relaxation diagnoses HIO very accurately, even at low iron concentrations. Important additional information may be obtained by the combination of T1 and T2* mapping. It is a rapid, non-invasive, accurate and reproducible technique for validating the evidence of even low hepatic iron concentrations. (orig.)

  18. Single-shot T1 mapping of the corpus callosum: A rapid characterization of fiber bundle anatomy

    Directory of Open Access Journals (Sweden)

    Sabine eHofer

    2015-05-01

    Full Text Available Using diffusion-tensor MRI and fiber tractography the topographic organization of the corpus callosum (CC has been described to comprise 5 segments with fibers projecting into prefrontal (I, premotor and supplementary motor (II, primary motor (III, and primary sensory areas (IV, as well as into parietal, temporal, and occipital cortical areas (V. In order to more rapidly characterize the underlying anatomy of these segments, this study used a novel single-shot T1 mapping method to quantitatively determine T1 relaxation times in the human CC. A region-of-interest analysis revealed a tendency for the lowest T1 relaxation times in the genu and the highest T1 relaxation times in the somatomotor region of the CC. This observation separates regions dominated by myelinated fibers with large diameters (somatomotor area from densely packed smaller axonal bundles (genu with less myelin. The results indicate that characteristic T1 relaxation times in callosal profiles provide an additional means to monitor differences in fiber anatomy, fiber density, and gray matter in respective neocortical areas. In conclusion, rapid T1 mapping allows for a characterization of the axonal architecture in an individual CC in less than 10 s. The approach emerges as a valuable means for studying neocortical brain anatomy with possible implications for the diagnosis of neurodegenerative processes.

  19. Relationship between knee alignment and T1ρ values of articular cartilage and menisci in patients with knee osteoarthritis

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Ligong, E-mail: ligong.wang@hotmail.com [Quantitative Multinuclear Musculoskeletal Imaging Group (QMMIG), Center for Biomedical Imaging, Department of Radiology, New York University Langone Medical Center, New York, NY 10016 (United States); School of Radiation Medicine and Protection, Medical College of Soochow University, School for Radiological and interdisciplinary Sciences (RAD-X), Soochow University, Suzhou, Jiangsu 215123 (China); Vieira, Renata La Rocca, E-mail: relarocca@gmail.com [Quantitative Multinuclear Musculoskeletal Imaging Group (QMMIG), Center for Biomedical Imaging, Department of Radiology, New York University Langone Medical Center, New York, NY 10016 (United States); Rybak, Leon D., E-mail: Leon.Rybak@nyumc.org [Quantitative Multinuclear Musculoskeletal Imaging Group (QMMIG), Center for Biomedical Imaging, Department of Radiology, New York University Langone Medical Center, New York, NY 10016 (United States); Babb, James S., E-mail: James.Babb@nyumc.org [Quantitative Multinuclear Musculoskeletal Imaging Group (QMMIG), Center for Biomedical Imaging, Department of Radiology, New York University Langone Medical Center, New York, NY 10016 (United States); Chang, Gregory, E-mail: gregory.chang@nyumc.org [Quantitative Multinuclear Musculoskeletal Imaging Group (QMMIG), Center for Biomedical Imaging, Department of Radiology, New York University Langone Medical Center, New York, NY 10016 (United States); Krasnokutsky, Svetlana, E-mail: Svetlana.Krasnokutsky@nyumc.org [Department of Rheumatology, New York University Hospital for Joint Diseases, 301 East 17th Street, New York, NY 10003 (United States); Abramson, Steven, E-mail: StevenB.Abramson@nyumc.org [Department of Rheumatology, New York University Hospital for Joint Diseases, 301 East 17th Street, New York, NY 10003 (United States); and others

    2013-11-01

    Objective: To assess the relationship between knee alignment and subregional T1ρ values of the femorotibial cartilage and menisci in patients with mild (Kellgren–Lawrence grade 1) to moderate (KL3) osteoarthritis (OA) at 3 T. Materials and methods: 26 subjects with a clinical diagnosis of KL1-3 OA were included and subdivided into three subgroups: varus, valgus, and neutral. All subjects were evaluated on a 3 T MR scanner. Mann–Whitney and Wilcoxon signed rank tests were performed to determine any statistically significant differences in subregional T1ρ values of femorotibial cartilage and menisci among the three subgroups of KL1-3 OA patients. Results: Medial femoral anterior cartilage subregion in varus group had significantly higher (p < 0.05) T1ρ values than all cartilage subregions in valgus group. Medial tibial central cartilage subregion had significantly higher T1ρ values (p < 0.05) than lateral tibial central cartilage subregion in varus group. The posterior horn of the medial meniscus in neutral group had significantly higher T1ρ values (p < 0.0029) than all meniscus subregions in valgus group. Conclusion: There exists some degree of association between knee alignment and subregional T1ρ values of femorotibial cartilage and menisci in patients with clinical OA.

  20. Image Registration Strategy of T1-Weighted and FIESTA MRI Sequences in Trigeminal Neuralgia Gamma Knife Radiosurgery

    Science.gov (United States)

    Wang, Tony J.C.; Brisman, Ronald; Lu, Zheng Feng; Li, Xiang; Isaacson, Steven R.; Shah, Jinesh N.; Yoshida, Emi J.; Liu, Tian

    2010-01-01

    Background/Aims In Gamma Knife radiosurgery, T1 MRI is most commonly used and is generally sufficient for targeting the trigeminal nerve. For patients whose trigeminal nerves are unclear on T1 MRI, FIESTA MRI supplements anatomical structure visualization and may improve trigeminal nerve delineation. The purpose of this study was to develop a registration strategy for T1 and FIESTA MRIs. Methods We conducted a retrospective study on 54 trigeminal neuralgia patients. All patients were scanned with T1 and FIESTA MRIs. We evaluated 4 methods of registration: automatic image definition, superior-slice definition, middle-slice definition and inferior-slice definition. Target discrepancies were measured by deviations from an intracranial landmark on T1 and FIESTA MR images. Results The overall range in registration error was 0.10–5.19 mm using superior-, 0.10–1.56 mm using middle- and 0.14–2.89 mm using inferior-slice definition. Registration error >2 mm was observed in 11% of the patients using superior-, 4% using middle- and 7% using inferior-slice FIESTA MRI definition. Conclusions Among patients for whom FIESTA and T1 MRI are used, registration based on middle-slice definition reduces registration error and improves targeting of the trigeminal nerve. PMID:20530977

  1. Image registration strategy of T(1)-weighted and FIESTA MRI sequences in trigeminal neuralgia gamma knife radiosurgery.

    Science.gov (United States)

    Wang, Tony J C; Brisman, Ronald; Lu, Zheng Feng; Li, Xiang; Isaacson, Steven R; Shah, Jinesh N; Yoshida, Emi J; Liu, Tian

    2010-01-01

    In Gamma Knife radiosurgery, T(1) MRI is most commonly used and is generally sufficient for targeting the trigeminal nerve. For patients whose trigeminal nerves are unclear on T(1) MRI, FIESTA MRI supplements anatomical structure visualization and may improve trigeminal nerve delineation. The purpose of this study was to develop a registration strategy for T(1) and FIESTA MRIs. We conducted a retrospective study on 54 trigeminal neuralgia patients. All patients were scanned with T(1) and FIESTA MRIs. We evaluated 4 methods of registration: automatic image definition, superior-slice definition, middle-slice definition and inferior-slice definition. Target discrepancies were measured by deviations from an intracranial landmark on T(1) and FIESTA MR images. The overall range in registration error was 0.10-5.19 mm using superior-, 0.10-1.56 mm using middle- and 0.14-2.89 mm using inferior-slice definition. Registration error >2 mm was observed in 11% of the patients using superior-, 4% using middle- and 7% using inferior-slice FIESTA MRI definition. Among patients for whom FIESTA and T(1) MRI are used, registration based on middle-slice definition reduces registration error and improves targeting of the trigeminal nerve. 2010 S. Karger AG, Basel.

  2. Optimized T1- and T2-weighted volumetric brain imaging as a diagnostic tool in very preterm neonates

    Energy Technology Data Exchange (ETDEWEB)

    Nossin-Manor, Revital [Neurosciences and Mental Health, Research Institute, Department of Diagnostic Imaging, The Hospital for Sick Children, Toronto (Canada); Chung, Andrew D.; Morris, Drew; Thomas, Bejoy; Shroff, Manohar M. [The Hospital for Sick Children, Department of Diagnostic Imaging, Toronto (Canada); Soares-Fernandes, Joao P. [The Hospital for Sick Children, Department of Diagnostic Imaging, Toronto (Canada); Hospital de S. Marcos, Neuroradiology Department, Braga (Portugal); Cheng, Hai-Ling M. [The Hospital for Sick Children, Department of Diagnostic Imaging, Physiology Experimental Medicine, Research Institute, Toronto (Canada); University of Toronto, Medical Biophysics Department, Toronto (Canada); Whyte, Hilary E.A. [Neurosciences and Mental Health, Research Institute, Neonatology Department, The Hospital for Sick Children, Toronto (Canada); Taylor, Margot J. [The Hospital for Sick Children, Neurosciences and Mental Health, Research Institute, Department of Diagnostic Imaging, Toronto (Canada); University of Toronto, Medical Imaging, Toronto (Canada); Sled, John G. [University of Toronto, Physiology Experimental Medicine, Research Institute, The Hospital for Sick Children, Medical Biophysics, Toronto (Canada)

    2011-06-15

    T1- and T2-W MR sequences used for obtaining diagnostic information and morphometric measurements in the neonatal brain are frequently acquired using different imaging protocols. Optimizing one protocol for obtaining both kinds of information is valuable. To determine whether high-resolution T1- and T2-W volumetric sequences optimized for preterm brain imaging could provide both diagnostic and morphometric value. Thirty preterm neonates born between 24 and 32 weeks' gestational age were scanned during the first 2 weeks after birth. T1- and T2-W high-resolution sequences were optimized in terms of signal-to-noise ratio, contrast-to-noise ratio and scan time and compared to conventional spin-echo-based sequences. No differences were found between conventional and high-resolution T1-W sequences for diagnostic confidence, image quality and motion artifacts. A preference for conventional over high-resolution T2-W sequences for image quality was observed. High-resolution T1 images provided better delineation of thalamic myelination and the superior temporal sulcus. No differences were found for detection of myelination and sulcation using conventional and high-resolution T2-W images. High-resolution T1- and T2-W volumetric sequences can be used in clinical MRI in the very preterm brain to provide both diagnostic and morphometric information. (orig.)

  3. Single-shot T1 mapping of the corpus callosum: a rapid characterization of fiber bundle anatomy.

    Science.gov (United States)

    Hofer, Sabine; Wang, Xiaoqing; Roeloffs, Volkert; Frahm, Jens

    2015-01-01

    Using diffusion-tensor magnetic resonance imaging and fiber tractography the topographic organization of the human corpus callosum (CC) has been described to comprise five segments with fibers projecting into prefrontal (I), premotor and supplementary motor (II), primary motor (III), and primary sensory areas (IV), as well as into parietal, temporal, and occipital cortical areas (V). In order to more rapidly characterize the underlying anatomy of these segments, this study used a novel single-shot T1 mapping method to quantitatively determine T1 relaxation times in the human CC. A region-of-interest analysis revealed a tendency for the lowest T1 relaxation times in the genu and the highest T1 relaxation times in the somatomotor region of the CC. This observation separates regions dominated by myelinated fibers with large diameters (somatomotor area) from densely packed smaller axonal bundles (genu) with less myelin. The results indicate that characteristic T1 relaxation times in callosal profiles provide an additional means to monitor differences in fiber anatomy, fiber density, and gray matter in respective neocortical areas. In conclusion, rapid T1 mapping allows for a characterization of the axonal architecture in an individual CC in less than 10 s. The approach emerges as a valuable means for studying neocortical brain anatomy with possible implications for the diagnosis of neurodegenerative processes.

  4. Performance of the New South Wales Ambulance Service major trauma transport protocol (T1) at an inner city trauma centre.

    Science.gov (United States)

    Dinh, Michael M; Oliver, Matthew; Bein, Kendall J; Roncal, Susan; Byrne, Christopher M

    2012-08-01

    To evaluate the performance of a newly implemented prehospital trauma triage (T1) protocol in New South Wales for patients transported to an inner city major trauma centre. An observational study was conducted over 1 year. Prehospital data and injury characteristics were collected prospectively for all hospital trauma team activations and injury presentations transported by Ambulance Service of New South Wales. Univariate comparison of T1- and non-T1-transported patients was performed and sensitivity, specificity, overtriage and undertriage rates were calculated. The outcomes studied were Injury Severity Score >15 and major outcome (composite of in-hospital death and/or transferred from the ED to operating theatre or intensive care unit). Factors associated with undertriage were determined with univariate analysis. A total of 2664 ambulance arrivals for trauma were studied with 767(29%) transported on the T1 protocol. T1-transported patients were associated with more severe injury (23% vs 6%, P protocol for severe injury was 63% with a positive predictive value of 23%. The undertriage and overtriage rates for severe injury were 12% and 77%, respectively. Undertriaged patients were elderly with falls as the predominant mechanism of injury. The sensitivity and undertriage rates associated with the T1 protocol indicate the ongoing need for secondary triage at designated trauma centres and refinement of the protocol to include age as a criterion. © 2012 The Authors. EMA © 2012 Australasian College for Emergency Medicine and Australasian Society for Emergency Medicine.

  5. Medial meniscal posterior root/horn radial tears correlate with cartilage degeneration detected by T1ρ relaxation mapping

    Energy Technology Data Exchange (ETDEWEB)

    Takahashi, Kenji, E-mail: Kenji-am@nms.ac.jp [Department of Orthopaedic Surgery, Nippon Medical School, 1-1-5 Sendagi, Bunkyo-ku, Tokyo 113-8603 (Japan); Hashimoto, Sanshiro, E-mail: info@msorc.jp [Minami-Shinjuku Orthopaedic Rehabilitation Clinic, 2-16-7 Yoyogi, Shibuya-ku, Tokyo 151-0053 (Japan); Nakamura, Hiroshi, E-mail: nakamura@nms.ac.jp [Department of Orthopaedic Surgery, Nippon Medical School, 1-1-5 Sendagi, Bunkyo-ku, Tokyo 113-8603 (Japan); Mori, Atsushi, E-mail: atsu@nms.ac.jp [Department of Orthopaedic Surgery, Nippon Medical School, 1-1-5 Sendagi, Bunkyo-ku, Tokyo 113-8603 (Japan); Sato, Akiko, E-mail: akiko-sato@nms.ac.jp [Department of Orthopaedic Surgery, Nippon Medical School, 1-1-5 Sendagi, Bunkyo-ku, Tokyo 113-8603 (Japan); Majima, Tokifumi, E-mail: tkmajima@iuhw.ac.jp [Department of Orthopaedic Surgery, International University of Health and Welfare Hospital, 537-3 Iguchi, Nasu-shiobara, Tochigi 329-2763 (Japan); Takai, Shinro, E-mail: takai-snr@nms.ac.jp [Department of Orthopaedic Surgery, Nippon Medical School, 1-1-5 Sendagi, Bunkyo-ku, Tokyo 113-8603 (Japan)

    2015-06-15

    Highlights: • Posterior radial tears in medial meniscus associate T1ρ values of cartilage. • Posterior radial tears relate to cartilage degeneration even in early-stage osteoarthritis. • Abnormalities in meniscus on MRI are useful for screening early-stage osteoarthritis. - Abstract: Objective: This study aimed to identify factors on routine pulse sequence MRI associated with cartilage degeneration observed on T1ρ relaxation mapping. Materials and methods: This study included 137 subjects with knee pain. T1ρ values were measured in the regions of interest on the surface layer of the cartilage on mid-coronal images of the femorotibial joint. Assessment of cartilage, subchondral bone, meniscus and ligaments was performed using routine pulse sequence MRI. Radiographic evaluation for osteoarthritis was also performed. Results: Multiple regression analysis revealed posterior root/horn tears to be independent factors increasing the T1ρ values of the cartilage in the medial compartment of the femorotibial joint. Even when adjusted for radiographically defined early-stage osteoarthritis, medial posterior meniscal radial tears significantly increased the T1ρ values. Conclusions: This study showed that posterior root/horn radial tears in the medial meniscus are particularly important MRI findings associated with cartilage degeneration observed on T1ρ relaxation mapping. Morphological factors of the medial meniscus on MRI provide findings useful for screening early-stage osteoarthritis.

  6. CHANG'E-5T1 extended mission: The first lunar libration point flight via a lunar swing-by

    Science.gov (United States)

    Liu, Lei; Li, Ji-sheng

    2016-08-01

    This paper introduces the extended mission of the Chinese circumlunar return and reentry test (i.e., the CHANG'E-5T1 mission), the first Chinese flight in the Earth-Moon libration orbit and the first spacecraft to reach the Earth-Moon libration orbit via a lunar swing-by. The extended mission utilized the remaining propellant from the CHANG'E-5T1 mission. Based on the normal trajectory and satellite state at the end of the CHANG'E-5T1 mission, a lunar return and a flight in the lunar libration orbit were determined to be the flight goals of the extended mission. Two schemes were then proposed for the CHANG'E-5T1 extended mission, including a possible Earth-Moon libration orbit. The methodology for the trajectory design and maneuvering included the direct libration-point orbit transfer and injection method, which is characterized by a reduced calculation burden compared with the prevalent invariant manifold method. The scenarios were compared in terms of flight time, control energy and number of maneuvers, flight distance, and achieved flight goals. The comparison indicated that the scheme, including the Earth-Moon L2 point and return to the Moon, was preferred for the CHANG'E-5T1 extended mission. Furthermore, the actual flight parameters of the CHANG'E-5T1 extended mission are also presented to validate the selected scheme.

  7. High signal intensity of globus pallidus on T1-weighted MRI in liver cirrhosis patients. Clinical and pathological study

    Energy Technology Data Exchange (ETDEWEB)

    Ihara, Hiroko [Wakayama Medical Coll. (Japan)

    1998-08-01

    In some patients with liver cirrhosis, the globus pallidus shows high signal intensity on T1-weighted MRI. The relationship was examined between high signal intensity on T1-weighted images and pathological conditions such as liver function, portal venous pressure and metal concentrations in brain. The signal of the globus pallidus on T1-weighted imaging became highly enhanced in accordance with prolongation of prothrombin time, deterioration of ICG R{sub 15}, or decrease in choline esterase and the Fisher ratio. Furthermore, the high signal intensity was also seen in patients with high portal pressure and large varices. In histopathological study, remarkable atrophy and loss of nerve cells were observed in globus pallidus with high signal intensity on T1-weighted imaging, changes that were similar to those in with patients with manganese poisoning. The manganese concentration in autopsied globus pallidus with high signal intensity on T1-weighted imaging showed a 9.5-fold increase compared with that with normal intensity. In conclusion, the deposition of manganese in the globus pallidus, which is accompanied with the nerve cell deciduation, brings about the high signal intensity of the globus pallidus on T1-weighted MRI in patients with liver cirrhosis. (author)

  8. DNase Sda1 allows invasive M1T1 Group A Streptococcus to prevent TLR9-dependent recognition.

    Directory of Open Access Journals (Sweden)

    Satoshi Uchiyama

    Full Text Available Group A Streptococcus (GAS has developed a broad arsenal of virulence factors that serve to circumvent host defense mechanisms. The virulence factor DNase Sda1 of the hyperinvasive M1T1 GAS clone degrades DNA-based neutrophil extracellular traps allowing GAS to escape extracellular killing. TLR9 is activated by unmethylated CpG-rich bacterial DNA and enhances innate immune resistance. We hypothesized that Sda1 degradation of bacterial DNA could alter TLR9-mediated recognition of GAS by host innate immune cells. We tested this hypothesis using a dual approach: loss and gain of function of DNase in isogenic GAS strains and presence and absence of TLR9 in the host. Either DNA degradation by Sda1 or host deficiency of TLR9 prevented GAS induced IFN-α and TNF-α secretion from murine macrophages and contributed to bacterial survival. Similarly, in a murine necrotizing fasciitis model, IFN-α and TNF-α levels were significantly decreased in wild type mice infected with GAS expressing Sda1, whereas no such Sda1-dependent effect was seen in a TLR9-deficient background. Thus GAS Sda1 suppressed both the TLR9-mediated innate immune response and macrophage bactericidal activity. Our results demonstrate a novel mechanism of bacterial innate immune evasion based on autodegradation of CpG-rich DNA by a bacterial DNase.

  9. Temporal and spatial characteristics of the area at risk investigated using computed tomography and T1-weighted magnetic resonance imaging

    DEFF Research Database (Denmark)

    van der Pals, Jesper; Hammer-Hansen, Sophia; Nielles-Vallespin, Sonia

    2015-01-01

    the AAR. We investigated the presence of a lateral perfusion gradient within the AAR and validated CMR measures of AAR against three independent reference standards of high quality. METHODS AND RESULTS: Computed tomography (CT) perfusion imaging, microsphere blood flow analysis, T1-weighted 3T CMR...... and fluorescent microparticle pathology were used to investigate the AAR in a canine model (n = 10) of ischaemia and reperfusion. AAR size by CMR correlated well with CT (R(2) = 0.80), microsphere blood flow (R(2) = 0.80), and pathology (R(2) = 0.74) with good limits of agreement [-0.79 ± 4.02% of the left...... ventricular mass (LVM) vs. CT; -1.49 ± 4.04% LVM vs. blood flow and -1.01 ± 4.18% LVM vs. pathology]. The lateral portion of the AAR had higher perfusion than the core of the AAR by CT perfusion imaging (40.7 ± 11.8 vs. 25.2 ± 17.7 Hounsfield units, P = 0.0008) and microsphere blood flow (0.11 ± 0.04 vs. 0...

  10. Parallel Comparative Studies on Mouse Toxicity of Oxide Nanoparticle- and Gadolinium-Based T1 MRI Contrast Agents.

    Science.gov (United States)

    Chen, Rui; Ling, Daishun; Zhao, Lin; Wang, Shuaifei; Liu, Ying; Bai, Ru; Baik, Seungmin; Zhao, Yuliang; Chen, Chunying; Hyeon, Taeghwan

    2015-12-22

    Magnetic resonance imaging (MRI) contrast agents with high relaxivity are highly desirable because they can significantly increase the accuracy of diagnosis. However, they can be potentially toxic to the patients. In this study, using a mouse model, we investigate the toxic effects and subsequent tissue damage induced by three T1 MRI contrast agents: gadopentetate dimeglumine injection (GDI), a clinically used gadolinium (Gd)-based contrast agent (GBCAs), and oxide nanoparticle (NP)-based contrast agents, extremely small-sized iron oxide NPs (ESIONs) and manganese oxide (MnO) NPs. Biodistribution, hematological and histopathological changes, inflammation, and the endoplasmic reticulum (ER) stress responses are evaluated for 24 h after intravenous injection. These thorough assessments of the toxic and stress responses of these agents provide a panoramic description of safety concerns and underlying mechanisms of the toxicity of contrast agents in the body. We demonstrate that ESIONs exhibit fewer adverse effects than the MnO NPs and the clinically used GDI GBCAs, providing useful information on future applications of ESIONs as potentially safe MRI contrast agents.

  11. DNase Sda1 allows invasive M1T1 Group A Streptococcus to prevent TLR9-dependent recognition.

    Directory of Open Access Journals (Sweden)

    Satoshi Uchiyama

    Full Text Available Group A Streptococcus (GAS has developed a broad arsenal of virulence factors that serve to circumvent host defense mechanisms. The virulence factor DNase Sda1 of the hyperinvasive M1T1 GAS clone degrades DNA-based neutrophil extracellular traps allowing GAS to escape extracellular killing. TLR9 is activated by unmethylated CpG-rich bacterial DNA and enhances innate immune resistance. We hypothesized that Sda1 degradation of bacterial DNA could alter TLR9-mediated recognition of GAS by host innate immune cells. We tested this hypothesis using a dual approach: loss and gain of function of DNase in isogenic GAS strains and presence and absence of TLR9 in the host. Either DNA degradation by Sda1 or host deficiency of TLR9 prevented GAS induced IFN-α and TNF-α secretion from murine macrophages and contributed to bacterial survival. Similarly, in a murine necrotizing fasciitis model, IFN-α and TNF-α levels were significantly decreased in wild type mice infected with GAS expressing Sda1, whereas no such Sda1-dependent effect was seen in a TLR9-deficient background. Thus GAS Sda1 suppressed both the TLR9-mediated innate immune response and macrophage bactericidal activity. Our results demonstrate a novel mechanism of bacterial innate immune evasion based on autodegradation of CpG-rich DNA by a bacterial DNase.

  12. A 0.8-2.4 Micron Transmission Spectrum of the Hot Jupiter CoRoT-1b

    CERN Document Server

    Schlawin, Everett; Teske, Johanna K; Herter, Terry

    2014-01-01

    Hot Jupiters with brightness temperatures > ~2000K can have TiO and VO molecules as gaseous species in their atmospheres. The TiO and VO molecules can potentially induce temperature inversions in hot Jupiter atmospheres and also have an observable signature of large optical to infrared transit depth ratios. Previous transmission spectra of very hot Jupiters have shown a lack of TiO and VO, but only in planets that also appear to lack temperature inversions. We measure the transmission spectrum of CoRoT-1b, a hot Jupiter that was predicted to have a temperature inversion potentially due to significant TiO and VO in its atmosphere. We employ the multi-object spectroscopy (MOS) method using the SpeX and MORIS instruments on the Infrared Telescope Facility (IRTF) and the Gaussian Process method to model red noise. By using a simultaneous reference star on the slit for calibration and a wide slit to minimize slit losses, we achieve transit depth precision of 0.03% to 0.09%, comparable to the atmospheric scale heig...

  13. Estimation of free copper ion concentrations in blood serum using T1 relaxation rates

    Science.gov (United States)

    Blicharska, Barbara; Witek, Magdalena; Fornal, Maria; MacKay, Alex L.

    2008-09-01

    The water proton relaxation rate constant R1 = 1/ T1 (at 60 MHz) of blood serum is substantially increased by the presence of free Cu 2+ ions at concentrations above normal physiological levels. Addition of chelating agents to serum containing paramagnetic Cu 2+ nulls this effect. This was demonstrated by looking at the effect of adding a chelating agent—D-penicillamine (D-PEN) to CuSO 4 and CuCl 2 aqueous solutions as well as to rabbit blood serum. We propose that the measurement of water proton spin-lattice relaxation rate constants before and after chelation may be used as an alternative approach for monitoring the presence of free copper ions in blood serum. This method may be used in the diagnosis of some diseases (leukaemia, liver diseases and particularly Wilson's disease) because, in contrast to conventional methods like spectrophotometry which records the total number of both bound and free ions, the proton relaxation technique is sensitive solely to free paramagnetic ions dissolved in blood serum. The change in R1 upon chelation was found to be less than 0.06 s -1 for serum from healthy subjects but greater than 0.06 s -1 for serum from untreated Wilson's patients.

  14. Quantification of the host response proteome after mammalian reovirus T1L infection.

    Directory of Open Access Journals (Sweden)

    Alicia R Berard

    Full Text Available All viruses are dependent upon host cells for replication. Infection can induce profound changes within cells, including apoptosis, morphological changes, and activation of signaling pathways. Many of these alterations have been analyzed by gene arrays to measure the cellular "transcriptome." We used SILAC (stable isotope labeling by amino acids in cell culture, combined with high-throughput 2-D HPLC/mass spectrometry, to determine relative quantitative differences in host proteins at 6 and 24 hours after infecting HEK293 cells with reovirus serotype 1 Lang (T1L. 3,076 host proteins were detected at 6 hpi, of which 132 and 68 proteins were significantly up or down regulated, respectively. 2,992 cellular proteins, of which 104 and 49 were up or down regulated, respectively, were identified at 24 hpi. IPA and DAVID analyses indicated proteins involved in cell death, cell growth factors, oxygen transport, cell structure organization and inflammatory defense response to virus were up-regulated, whereas proteins involved in apoptosis, isomerase activity, and metabolism were down-regulated. These proteins and pathways may be suitable targets for intervention to either attenuate virus infection or enhance oncolytic potential.

  15. Transgenic American chestnuts show enhanced blight resistance and transmit the trait to T1 progeny.

    Science.gov (United States)

    Newhouse, Andrew E; Polin-McGuigan, Linda D; Baier, Kathleen A; Valletta, Kristia E R; Rottmann, William H; Tschaplinski, Timothy J; Maynard, Charles A; Powell, William A

    2014-11-01

    American chestnut (Castanea dentata) is a classic example of a native keystone species that was nearly eradicated by an introduced fungal pathogen. This report describes progress made toward producing a fully American chestnut tree with enhanced resistance to the blight fungus (Cryphonectria parasitica). The transgenic American chestnut 'Darling4,' produced through an Agrobacterium co-transformation procedure to express a wheat oxalate oxidase gene driven by the VspB vascular promoter, shows enhanced blight resistance at a level intermediate between susceptible American chestnut and resistant Chinese chestnut (Castanea mollissima). Enhanced resistance was identified first with a leaf-inoculation assay using young chestnuts grown indoors, and confirmed with traditional stem inoculations on 3- and 4-year-old field-grown trees. Pollen from 'Darling4' and other events was used to produce transgenic T1 seedlings, which also expressed the enhanced resistance trait in leaf assays. Outcrossed transgenic seedlings have several advantages over tissue-cultured plantlets, including increased genetic diversity and faster initial growth. This represents a major step toward the restoration of the majestic American chestnut.

  16. Measurements of hot electrons in the Extrap T1 reversed-field pinch

    Science.gov (United States)

    Welander, A.; Bergsåker, H.

    1998-02-01

    The presence of an anisotropic energetic electron population in the edge region is a characteristic feature of reversed-field pinch (RFP) plasmas. In the Extrap T1 RFP, the anisotropic, parallel heat flux in the edge region measured by calorimetry was typically several hundred 0741-3335/40/2/011/img1. To gain more insight into the origin of the hot electron component and to achieve time resolution of the hot electron flow during the discharge, a target probe with a soft x-ray monitor was designed, calibrated and implemented. The x-ray emission from the target was measured with a surface barrier detector covered with a set of different x-ray filters to achieve energy resolution. A calibration in the range 0.5-2 keV electron energy was performed on the same target and detector assembly using a 0741-3335/40/2/011/img2 cathode electron gun. The calibration data are interpolated and extrapolated numerically. A directional asymmetry of more than a factor of 100 for the higher energy electrons is observed. The hot electrons are estimated to constitute 10% of the total electron density at the edge and their energy distribution is approximated by a half-Maxwellian with a temperature slightly higher than the central electron temperature. Scalings with plasma current, as well as correlations with local 0741-3335/40/2/011/img3 measurements and radial dependences, are presented.

  17. Miners compensated for pneumoconiosis and glutathione s-transferases M1 and T1 genotypes.

    Science.gov (United States)

    Zimmermann, Anna; Ebbinghaus, Rainer; Prager, Hans-Martin; Blaszkewicz, Meinolf; Hengstler, Jan G; Golka, Klaus

    2012-01-01

    Chronic inhalation of quartz-containing dust produces reversible inflammatory changes in lungs resulting in irreversible fibrotic changes termed pneumoconiosis. Due to the inflammatory process in the lungs, highly reactive substances are released that may be detoxified by glutathione S-transferases. Therefore, 90 hard coal miners with pneumoconiosis as a recognized occupational disease (in Germany: Berufskrankheit BK 4101) were genotyped for glutathione S-transferases M1 (GSTM1) and T1 (GSTT1) according to standard methods. Furthermore, occupational exposure and smoking habits were assessed by questionnaire. Changes in a chest x-ray were classified according to ILO classification 2000. Of the investigated hard coal miners 43% were GSTM1 negative whereas 57% were GSTM1 positive. The arithmetic mean of the age at time of investigation was 74.2 yr (range: 42-87 yr). Seventy-four percent of the hard coal miners reported being ever smokers, while 26% denied smoking. All hard coal miners provided pneumoconiosis-related changes in the chest x-ray. The observed frequency of GSTM1 negative hard coal miners was not different from frequencies reported for general Caucasian populations and in agreement with findings reported for Chinese coal miners. In contrast, in a former study, 16 of 19 German hard coal miners (84%) with urinary bladder cancer displayed a GSTM1 negative genotype. The outcome of this study provides evidence that severely occupationally exposed Caucasian hard coal miners do not present an elevated level of GSTM1 negative individuals.

  18. Glutathione s-transferase M1 and T1 genetic polymorphisms in Iranian patients with glaucoma

    Directory of Open Access Journals (Sweden)

    Fatemeh Kazemi Safa

    2014-05-01

    Full Text Available Objective(s:Glaucoma is the second leading cause of blindness and it is related to oxidative stress based on numerous studies. Glutathione S-transferases (GSTs are members of multigenic family, which have important role in cells as an antioxidant. In the present study, we examined the polymorphism of GSTT1 and GSTM1 deletion genotypes (T0M1, T1M0, and T0M0 in 100 Glaucoma patients (41with primary open angle glaucoma (PCAG, and 59 with primary closed angle glaucoma (POAG compared to 100 healthy subjects. Materials and Methods: GSTM1and GSTT1 polymorphisms were determined by multiplex polymerase chain reaction. Results: GSTM1 and GSTT1 null deletions genotypes were determined in 22 (53.7% and 7 (17.1% patients with PCAG and 34 (34% and 15 (15% in healthy subjects[VAIO1] . Comparison between patients and healthy subjects regarding GSTM1 and GSTT1 genotypes revealed increase of GSTM1 null deletions genotypes in patients with PCAG (P=0.03. Conclusion: It was concluded that the increased frequencies of GSTM1 null in patients with PCAG could be a risk factor for incidence of PCAG in the Iranian population.  

  19. Tunneling at νT = 1 in a bilayer quantum Hall exciton condensate

    Science.gov (United States)

    Nandi, D.; Khaire, T.; Finck, A. D. K.; Eisenstein, J. P.; Pfeiffer, L. N.; West, K. W.

    2014-03-01

    Closely-spaced bilayer quantum Hall systems at total filling factor νT = 1 exhibit spontaneous interlayer phase coherence. This phase coherence, which is tantamount to excitonic Bose condensation, is most dramatically revealed via interlayer tunneling measurements.In the condensed phase the tunneling current-voltage (IV) characteristic of this semiconductor system strongly resembles the dc Josephson effect observed in superconducting tunnel junctions. Here we report on a detailed study of this phenomenon. We find the maximum, or critical tunneling current Ic to be a well-defined global property of the macroscopic tunnel junction, insensitive to external circuit elements and the precise contact configuration used to observe it. Interestingly, the temperature dependence of Ic displays an unexpected scaling behavior. At the lowest temperatures the slope of the ``supercurrent'' branch of the tunneling IV curve, while extremely large, remains finite. Careful measurements in this regime suggest that dissipative processes arising from in-plane exciton transport limit the maximum tunneling conductance. Finally, comparisons of the experimentally observed IV with recent theoretical predictions will be discussed.

  20. The changing phases of extrasolar planet CoRoT-1b.

    Science.gov (United States)

    Snellen, Ignas A G; de Mooij, Ernst J W; Albrecht, Simon

    2009-05-28

    Hot Jupiters are a class of extrasolar planet that orbit their parent stars at very short distances. They are expected to be tidally locked, which can lead to a large temperature difference between their daysides and nightsides. Infrared observations of eclipsing systems have yielded dayside temperatures for a number of transiting planets. The day-night contrast of the transiting extrasolar planet HD 189733b was 'mapped' using infrared observations. It is expected that the contrast between the daysides and nightsides of hot Jupiters is much higher at visual wavelengths, shorter than that of the peak emission, and could be further enhanced by reflected stellar light. Here we report the analysis of optical photometric data obtained over 36 planetary orbits of the transiting hot Jupiter CoRoT-1b. The data are consistent with the nightside hemisphere of the planet being entirely black, with the dayside flux dominating the optical phase curve. This means that at optical wavelengths the planet's phase variation is just as we see it for the interior planets in the Solar System. The data allow for only a small fraction of reflected light, corresponding to a geometric albedo of <0.20.

  1. Icaritin synergistically enhances the radiosensitivity of 4T1 breast cancer cells.

    Directory of Open Access Journals (Sweden)

    Jinsheng Hong

    Full Text Available Icaritin (ICT is a hydrolytic form of icariin isolated from plants of the genus Epimedium. This study was to investigate the radiosensitization effect of icaritin and its possible underlying mechanism using murine 4T1 breast cancer cells. The combination of Icaritin at 3 µM or 6 µM with 6 or 8 Gy of ionizing radiation (IR in the clonogenic assay yielded an ER (enhancement ratio of 1.18 or 1.28, CI (combination index of 0.38 or 0.19 and DRI (dose reducing index of 2.51 or 5.07, respectively. These strongly suggest that Icaritin exerted a synergistic killing (? effect with radiation on the tumor cells. This effect might relate with bioactivities of ICT: 1 exert an anti-proliferative effect in a dose- and time-dependent manner, which is different from IR killing effect but likely work together with the IR effect; 2 suppress the IR-induced activation of two survival paths, ERK1/2 and AKT; 3 induce the G2/M blockage, enhancing IR killing effect; and 4 synergize with IR to enhance cell apoptosis. In addition, ICT suppressed angiogenesis in chick embryo chorioallantoic membrane (CAM assay. Taken together, ICT is a new radiosensitizer and can enhance anti-cancer effect of IR or other therapies.

  2. Eu, Gd-Codoped Yttria Nanoprobes for Optical and T1-Weighted Magnetic Resonance Imaging

    Science.gov (United States)

    Atabaev, Timur Sh; Lee, Jong Ho; Shin, Yong Cheol; Han, Dong-Wook; Choo, Ki Seok; Jeon, Ung Bae; Hwang, Jae Yeon; Yeom, Jeong A.; Kim, Hyung-Kook; Hwang, Yoon-Hwae

    2017-01-01

    Nanoprobes with multimodal functionality have attracted significant interest recently because of their potential applications in nanomedicine. This paper reports the successful development of lanthanide-doped Y2O3 nanoprobes for potential applications in optical and magnetic resonance (MR) imaging. The morphology, structural, and optical properties of these nanoprobes were characterized by transmission electron microscope (TEM), field emission scanning electron microscope (FESEM), X-ray diffraction (XRD), energy-dispersive X-ray (EDX), and photoluminescence (PL). The cytotoxicity test showed that the prepared lanthanide-doped Y2O3 nanoprobes have good biocompatibility. The obvious contrast enhancement in the T1-weighted MR images suggested that these nanoprobes can be used as a positive contrast agent in MRI. In addition, the clear fluorescence images of the L-929 cells incubated with the nanoprobes highlight their potential for optical imaging. Overall, these results suggest that prepared lanthanide-doped Y2O3 nanoprobes can be used for simultaneous optical and MR imaging. PMID:28336868

  3. Eu, Gd-Codoped Yttria Nanoprobes for Optical and T1-Weighted Magnetic Resonance Imaging

    Directory of Open Access Journals (Sweden)

    Timur Sh Atabaev

    2017-02-01

    Full Text Available Nanoprobes with multimodal functionality have attracted significant interest recently because of their potential applications in nanomedicine. This paper reports the successful development of lanthanide-doped Y2O3 nanoprobes for potential applications in optical and magnetic resonance (MR imaging. The morphology, structural, and optical properties of these nanoprobes were characterized by transmission electron microscope (TEM, field emission scanning electron microscope (FESEM, X-ray diffraction (XRD, energy-dispersive X-ray (EDX, and photoluminescence (PL. The cytotoxicity test showed that the prepared lanthanide-doped Y2O3 nanoprobes have good biocompatibility. The obvious contrast enhancement in the T1-weighted MR images suggested that these nanoprobes can be used as a positive contrast agent in MRI. In addition, the clear fluorescence images of the L-929 cells incubated with the nanoprobes highlight their potential for optical imaging. Overall, these results suggest that prepared lanthanide-doped Y2O3 nanoprobes can be used for simultaneous optical and MR imaging.

  4. Intramuscular adipose tissue determined by T1-weighted MRI at 3T primarily reflects extramyocellular lipids.

    Science.gov (United States)

    Akima, Hiroshi; Hioki, Maya; Yoshiko, Akito; Koike, Teruhiko; Sakakibara, Hisataka; Takahashi, Hideyuki; Oshida, Yoshiharu

    2016-05-01

    The purpose of this study was to assess relationships between intramuscular adipose tissue (IntraMAT) content determined by MRI and intramyocellular lipids (IMCL) and extramyocellular lipids (EMCL) determined by (1)H magnetic resonance spectroscopy ((1)H MRS) or echo intensity determined by B-mode ultrasonography of human skeletal muscles. Thirty young and elderly men and women were included. T1-weighted MRI was taken from the right mid-thigh to measure IntraMAT content of the vastus lateralis (VL) and biceps femoris (BF) using a histogram shape-based thresholding technique. IMCL and EMCL were measured from the VL and BF at the right mid-thigh using (1)H MRS. Ultrasonographic images were taken from the VL and BF of the right mid-thigh to measure echo intensity based on gray-scale level for quantitative analysis. There was a significant correlation between IntraMAT content by MRI and EMCL of the VL and BF (VL, r=0.506, Plipids, not intramyocellular lipids, in human skeletal muscles. Copyright © 2016 Elsevier Inc. All rights reserved.

  5. T1 mapping of the myocardium: intra-individual assessment of post-contrast T1 time evolution and extracellular volume fraction at 3T for Gd-DTPA and Gd-BOPTA

    Directory of Open Access Journals (Sweden)

    Kawel Nadine

    2012-04-01

    Full Text Available Abstract Purpose Myocardial T1 relaxation time (T1 time and extracellular volume fraction (ECV are altered in patients with diffuse myocardial fibrosis. The purpose of this study was to perform an intra-individual assessment of normal T1 time and ECV for two different contrast agents. Methods A modified Look-Locker Inversion Recovery (MOLLI sequence was acquired at 3 T in 24 healthy subjects (8 men; 28 ± 6 years at mid-ventricular short axis pre-contrast and every 5 min between 5-45 min after injection of a bolus of 0.15 mmol/kg gadopentetate dimeglumine (Gd-DTPA; Magnevist® (exam 1 and 0.1 mmol/kg gadobenate dimeglumine (Gd-BOPTA; Multihance® (exam 2 during two separate scanning sessions. T1 times were measured in myocardium and blood on generated T1 maps. ECVs were calculated as ΔR1myocardium/ΔR1blood*1−hematocrit. Results Mean pre-contrast T1 relaxation times for myocardium and blood were similar for both the first and second CMR exam (p > 0.5. Overall mean post-contrast myocardial T1 time was 15 ± 2 ms (2.5 ± 0.7% shorter for Gd-DTPA at 0.15 mmol/kg compared to Gd-BOPTA at 0.1 mmol/kg (p  0.05. Between 5 and 45 minutes after contrast injection, mean ECV values increased linearly with time for both contrast agents from 0.27 ± 0.03 to 0.30 ± 0.03 (p pre-contrast myocardial T1 relaxation time (CV 4.5% [exam 1] and 3.0% [exam 2], respectively. ECV with Gd-DTPA was highly correlated to ECV by Gd-BOPTA (r = 0.803; p  Conclusion In comparison to pre-contrast myocardial T1 relaxation time, variation in ECV values of normal subjects is larger. However, absolute differences in ECV between Gd-DTPA and Gd-BOPTA were small and rank correlation was high. There is a small and linear increase in ECV over time, therefore ideally images should be acquired at the same delay after contrast injection.

  6. T1 WI BLADE Dark Fluid 序列在头颅增强扫描中的应用价值%The value of contrast-enhanced T1 WI BLADE Dark Fluid sequence in the brain MR imaging

    Institute of Scientific and Technical Information of China (English)

    张海平; 敖国昆; 李利佳; 刘杰爱; 石清磊; 李帅

    2015-01-01

    目的:探讨 MR T1 WI BLADE Dark Fluid 增强序列在减少头颅运动伪影方面的应用价值。方法纳入颅内病变患者40例(颅内病变者30例),由2名放射科医师对 T1 WI BLADE Dark Fluid 增强序列和 T1 WI Dark Fluid 增强序列扫描所得图像分析,按照病变运动伪影程度行0~Ⅲ分级,并运用 Wilcoxon 符号秩检验比较分析。2名医师分别测量计算2种序列客观指标,灰白质对比度(CNRgw )、病变对比噪声比(CNRle )及脑白质信号噪声比(SNRwm ),取其均值为最终结果,采用配对 t 检验比较分析。结果 T1 WI BLADE Dark Fluid 序列头部运动伪影0、Ⅰ、Ⅱ、Ⅲ级病例数分别为21、9、0、0例,T1 WI Dark Fluid 序列分别为8、11、6、5例,T1 WI BLADE Dark Fluid 序列在减少运动伪影方面优于 T1 WI Dark Fluid 序列(Z =-5.130,P =0.000)。T1 WI BLADE Dark Fluid 序列 CNRgw (30.37±10.96)与 CNRle (87.36±45.32)高于 T1 WI Dark Fluid 的 CNRgw (24.48±10.55)与 CNRle (60.46±25.22),差异具有统计学意义(P =0.000,P =0.009),2种序列 SNRwm 分别为84.12±20.08、79.71±25.37,差异无统计学意义(P =0.169)。结论T1 WI BLADE Dark Fluid 序列可明显减少头颅检查过程中运动产生的伪影,在头颅增强 T1 WI 检查中具有较大的应用价值。%Objective To study the diagnostic value of contrast-enhanced T1 WI BLADE Dark Fluid in head MR examination. Methods Forty patients with suspected intracranial lesions were enrolled(thirty patients with intracranial lesions).The images of contrast-enhanced T1 WI BLADE Dark Fluid and contrast-enhanced T1 WI Dark Fluid were analyzed by two radiologists and classified from 0 to III degrees by motion artifacts of lesions.The results were analyzed using the Wilcoxon signed-ranks test.The quantitative parameters including the contrast to noise ratio between gray and white matter (CNRgw ),the contrast to noise ratio between white matter and lesion (CNRle )and the signal to noise ratio of white matter

  7. LTE 2×1T1R RRU覆盖技术及其应用建议%LTE 2×1T1R RRU Coverage Technique and Application Recommendations

    Institute of Scientific and Technical Information of China (English)

    魏坚; 吕文斌; 江海波

    2015-01-01

    LTE 2×1T1R RRU技术的优势包括提高主设备和光纤资源的利用率、减少功耗、提升用户数容量以及节能减排等;同时也存在一些短板,包括无法使用MIMO导致峰值速率降低和前向覆盖功率略有降低等。从LTE 2×1T1R RRU技术的优劣势出发,根据不同场景的个性化需求,对该技术的应用场景作了细分,同时对各细分场景使用LTE 2×1T1R RRU技术的关注点提出了建议。%The advantages of LTE 2×1T1R RRU technique include utilization improvement of main equipment and optical fiber resources, power reduction, user capacity increase and energy saving. However, some disadvantages are attached to the technique such as peak rate reduction resulted from no MIMO technique and forward coverage power reduction. In view of these disadvantages, the application scenes of the technique are precisely classified according to the demands of different scenes, while some recommendations on the application focus of LTE 2×1T1R RRU technique are presented.

  8. Predictive value of PWI for blood supply and T1-spin echo MRI for consistency of pituitary adenoma

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Zengyi; He, Wenqiang; Zhao, Yao; Zhang, Qilin; Li, Shiqi; Wang, Yongfei [Fudan University, Department of Neurosurgery, Huashan Hospital, Shanghai Medical College, Shanghai (China); Shanghai Pituitary Tumor Center, Shanghai (China); Yuan, Jie; Wu, Yue; Yao, Zhenwei [Fudan University, Department of Radiology, Huashan Hospital, Shanghai Medical College, Shanghai (China); Chen, Hong [Fudan University, Department of Neuropathology, Huashan Hospital, Shanghai Medical College, Shanghai (China)

    2016-01-15

    It is a common view that consistency and blood supply of pituitary adenoma (PA) can influence the surgical effect. The aim of this study was to determine whether MRI signal intensity (SI) was correlated to the consistency or blood supply of pituitary macroadenoma. Forty eight pituitary macroadenoma patients were underwent preoperative MRI, including precontrast and contrast-enhanced (CE) T1-spin echo (T1-SE) imaging, CE-sampling perfection with application-optimized contrasts by using different flip angle evolutions (SPACE) imaging, and perfusion-weighted imaging (PWI). The tumor consistency and blood supply were determined by neurosurgeons. The expression of collagen IV and MIB-1 was detected with immunohistology. The correlation of the relative SI (rSI) values (tumor to normal frontal white matter SI) and PWI data to the tumor consistency, blood supply, and the expression level of collagen IV and MIB-1 was statistically studied by Kruskal-Wallis rank test (K-W test). A significant correlation was observed between the tumor consistency and the rSI on precontrast T1-SE imaging (P = 0.004) but not on CE T1-SE and CE SPACE imaging. The expression of collagen IV was also significantly associated with rSI on T1-SE imaging (P = 0.010). The blood supply was correlated with the relative CBV (rCBV) (P = 0.030). In addition, the expression of MIB-1 was correlated with rSI of CE T1-SE imaging (P = 0.007). Our results suggest that T1-SE imaging may be a simple and useful method for predicting consistency of PA. CBV value can provide helpful information for assessing the blood supply of pituitary macroadenoma. (orig.)

  9. The ubiquitin ligase STUB1 regulates stability and activity of RUNX1 and RUNX1-RUNX1T1.

    Science.gov (United States)

    Yonezawa, Taishi; Takahashi, Hirotaka; Shikata, Shiori; Liu, Xiaoxiao; Tamura, Moe; Asada, Shuhei; Fukushima, Tsuyoshi; Fukuyama, Tomofusa; Tanaka, Yosuke; Sawasaki, Tatsuya; Kitamura, Toshio; Goyama, Susumu

    2017-07-28

    RUNX1 is a member of RUNX transcription factors and plays important roles in hematopoiesis. Disruption of RUNX1 activity has been implicated in the development of hematopoietic neoplasms. Chromosomal translocations involving the RUNX1 gene are associated with several types of leukemia, including acute myeloid leukemia driven by a leukemogenic fusion protein RUNX1-RUNX1T1. Previous studies have shown that RUNX1 is an unstable protein and is subjected to proteolytic degradation mediated by the ubiquitin-proteasome pathway. However, the precise mechanisms of RUNX1 ubiquitination have not been fully understood. Furthermore, much less is known about the mechanisms to regulate the stability of RUNX1-RUNX1T1. In this study, we identified several RUNX1-interacting E3 ubiquitin ligases using a novel high-throughput binding assay. Among them, we found that STUB1 bound to RUNX1 and induced its ubiquitination and degradation mainly in the nucleus. Immunofluorescence analyses revealed that the STUB1-induced ubiquitination also promoted nuclear export of RUNX1, which probably contributes to the reduced transcriptional activity of RUNX1 in STUB1-overexpressing cells. STUB1 also induced ubiquitination of RUNX1-RUNX1T1 and down-regulated its expression. Importantly, STUB1 overexpression showed a substantial growth-inhibitory effect in myeloid leukemia cells that harbor RUNX1-RUNX1T1, whereas it showed only a marginal effect in other non-RUNX1-RUNX1T1 leukemia cells and normal human cord blood cells. Taken together, these data suggest that the E3 ubiquitin ligase STUB1 is a negative regulator of both RUNX1 and RUNX1-RUNX1T1. Activation of STUB1 could be a promising therapeutic strategy for RUNX1-RUNX1T1 leukemia. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

  10. Adaptive registration of varying contrast-weighted images for improved tissue characterization (ARCTIC): application to T1 mapping.

    Science.gov (United States)

    Roujol, Sébastien; Foppa, Murilo; Weingärtner, Sebastian; Manning, Warren J; Nezafat, Reza

    2015-04-01

    To propose and evaluate a novel nonrigid image registration approach for improved myocardial T1 mapping. Myocardial motion is estimated as global affine motion refined by a novel local nonrigid motion estimation algorithm. A variational framework is proposed, which simultaneously estimates motion field and intensity variations, and uses an additional regularization term to constrain the deformation field using automatic feature tracking. The method was evaluated in 29 patients by measuring the DICE similarity coefficient and the myocardial boundary error in short axis and four chamber data. Each image series was visually assessed as "no motion" or "with motion." Overall T1 map quality and motion artifacts were assessed in the 85 T1 maps acquired in short axis view using a 4-point scale (1-nondiagnostic/severe motion artifact, 4-excellent/no motion artifact). Increased DICE similarity coefficient (0.78 ± 0.14 to 0.87 ± 0.03, P < 0.001), reduced myocardial boundary error (1.29 ± 0.72 mm to 0.84 ± 0.20 mm, P < 0.001), improved overall T1 map quality (2.86 ± 1.04 to 3.49 ± 0.77, P < 0.001), and reduced T1 map motion artifacts (2.51 ± 0.84 to 3.61 ± 0.64, P < 0.001) were obtained after motion correction of "with motion" data (∼56% of data). The proposed nonrigid registration approach reduces the respiratory-induced motion that occurs during breath-hold T1 mapping, and significantly improves T1 map quality. © 2014 Wiley Periodicals, Inc.

  11. Detecting ICRS grade 1 cartilage lesions in anterior cruciate ligament injury using T1ρ and T2 mapping

    Energy Technology Data Exchange (ETDEWEB)

    Nishioka, Hiroaki, E-mail: kinuhnishiok@fc.kuh.kumamoto-u.ac.jp [Department of Orthopaedic Surgery, Faculty of Life Sciences, Kumamoto University, 1-1-1 Honjo, Kumamoto 860-8556 (Japan); Hirose, Jun, E-mail: hirojun-mk@umin.ac.jp [Department of Orthopaedic Surgery, Kumamoto University Hospital, 1-1-1 Honjo, Kumamoto 860-8556 (Japan); Nakamura, Eiichi, E-mail: h@kumamoto-u.ac.jp [Department of Orthopaedic Surgery, Faculty of Life Sciences, Kumamoto University, 1-1-1 Honjo, Kumamoto 860-8556 (Japan); Okamoto, Nobukazu, E-mail: nobuoka9999@fc.kuh.kumamoto-u.ac.jp [Department of Orthopaedic Surgery, Faculty of Life Sciences, Kumamoto University, 1-1-1 Honjo, Kumamoto 860-8556 (Japan); Karasugi, Tatsuki, E-mail: tatsukik@fc.kuh.kumamoto-u.ac.jp [Department of Orthopaedic Surgery, Faculty of Life Sciences, Kumamoto University, 1-1-1 Honjo, Kumamoto 860-8556 (Japan); Taniwaki, Takuya, E-mail: takuyataniwaki@fc.kuh.kumamoto-u.ac.jp [Department of Orthopaedic Surgery, Faculty of Life Sciences, Kumamoto University, 1-1-1 Honjo, Kumamoto 860-8556 (Japan); Okada, Tatsuya, E-mail: tatsuya-okada@fc.kuh.kumamoto-u.ac.jp [Department of Orthopaedic Surgery, Faculty of Life Sciences, Kumamoto University, 1-1-1 Honjo, Kumamoto 860-8556 (Japan); Yamashita, Yasuyuki, E-mail: yama@kumamoto-u.ac.jp [Department of Diagnostic Radiology, Faculty of Life Sciences, Kumamoto University, 1-1-1 Honjo, Kumamoto 860-8556 (Japan); Mizuta, Hiroshi, E-mail: mizuta@kumamoto-u.ac.jp [Department of Orthopaedic Surgery, Faculty of Life Sciences, Kumamoto University, 1-1-1 Honjo, Kumamoto 860-8556 (Japan)

    2013-09-15

    Objective: The purpose of this study was to clarify the detectability of the International Cartilage Repair Society (ICRS) grade 1 cartilage lesions in anterior cruciate ligament (ACL)–injured knees using T1ρ and T2 mapping. Materials and Methods: We performed preoperative T1ρ and T2 mapping and 3D gradient–echo with water–selective excitation (WATS) sequences on 37 subjects with ACL injuries. We determined the detectability on 3D WATS based on arthroscopic findings. The T1ρ and T2 values (ms) were measured in the regions of interest that were placed on the weight–bearing cartilage of the femoral condyle. The receiver operating characteristic (ROC) curve based on these values was constructed using the arthroscopic findings as a reference standard. The evaluation of cartilage was carried out only in the weight–bearing cartilage. The cut–off values for determining the presence of a cartilage injury were determined using each ROC curve, and the detectability was calculated for the T1ρ and T2 mapping. Results: The cut–off values for the T1ρ and T2 were 41.6 and 41.2, respectively. The sensitivity and specificity of T1ρ were 91.2% and 89.5%, respectively, while those of T2 were 76.5% and 81.6%, respectively. For the 3D WATS images, the same values were 58.8% and 78.9%, respectively. Conclusions: Our study demonstrated that the T1ρ and T2 values were significantly higher for ICRS grade 1 cartilage lesions than for normal cartilage and that the two mappings were able to non–invasively detect ICRS grade 1 cartilage lesions in the ACL–injured knee with a higher detectability than were 3D WATS images.

  12. Isovector spin-singlet (T = 1, S = 0) and isoscalar spin-triplet (T = 0, S = 1) pairing interactions and spin-isospin response

    Science.gov (United States)

    Sagawa, H.; Bai, C. L.; Colò, G.

    2016-08-01

    We review several experimental and theoretical advances that emphasize common aspects of the study of spin-singlet, T = 1, and spin-triplet, T = 0, pairing correlations in nuclei. We first discuss various empirical evidence of the special role played by the T = 1 pairing interaction. In particular, we show the peculiar features of the nuclear pairing interaction in the low-density regime, and possible outcomes such as the BCS-BEC crossover in nuclear matter and, in an analogous way, in loosely bound nuclei. We then move to the competition between T = 1 and T = 0 pairing correlations. The effect of such competition on the low-lying spectra is studied in N = Z odd-odd nuclei by using a three-body model; in this case, it is shown that the inversion of the {J}π ={0}+ and {J}π ={1}+ states near the ground state, and the strong magnetic dipole transitions between them, can be considered as a clear manifestation of strong T = 0 pairing correlations in these nuclei. The effect of T = 0 pairing correlations is also quite evident if one studies charge-changing transitions. The Gamow-Teller (GT) states in N=Z+2 nuclei are studied here by using self-consistent Hartree-Fock-Bogoliubov (HFB) plus quasiparticle random-phase approximation calculations in which the T = 0 pairing interaction is taken into account. Strong GT states are found, near the ground state of daughter nuclei; these are compared with available experimental data from charge-exchange reactions, and such comparison can pinpoint the value of the strength of the T = 0 interaction. Pair transfer reactions are eventually discussed. While two-neutron transfer has long been proposed as a tool to measure the T = 1 superfluidity in the nuclear ground states, the study of deuteron transfer is still in its infancy, despite its potential interest for revealing effects coming from both T = 1 and T = 0 interactions. We also point out that the reaction mechanism may mask the strong pair transfer amplitudes predicted by the

  13. Preliminary study on articular cartilage MRI T1ρimaging in normal adults%正常膝关节软骨MRI T1ρ序列表现初步研究

    Institute of Scientific and Technical Information of China (English)

    李智慧; 陆勇; 蒋梅花; 杜联军; 丁晓毅; 严福华

    2014-01-01

    Objective To compare the performance of MRI T1ρand three-dimensional fat suppressed fasts poiled gradient echo (3D-FS-SPGR) sequence in normal knee articular cartilage, investigate the feasibility of T 1ρsequence for assessing cartilage, and evaluate the MRI T1ρdifference between deep and superficial layer of normal knee articular cartilage. Methods A total of 26 healthy volunteers confirmed by clinician and radiologist were enrolled, which included 11 males and 15 females;aged 15-65 years old with mean age of 31.69. The performance of MRI T1ρand 3D-FS-SPGR sequence were analyzed. The knee cartilage was divided into 6 segments:patellar cartilage, trochlear cartilage, medial and lateral femoral condyle cartilage, medial and lateral tibial cartilage. The MRI signal intensity of cartilage, subchondral bone, and the background noise was measured on the T 1ρfirst echo images and the same location 3D-FS-SPGR images. The cartilage/subchondral bone contrast ratio(CNR) and the cartilage ratio(SNR) were compared by paired t-test. The thickest cartilage of 6 segments was selected and the T 1ρvalues of deep layer and superficial layer were measured by the same pixel values. The T1ρ values were compared by paired t-test, and P < 0.05 was considered statistically significant. Results ①The mean value of CNR and SNR in T1ρsequence on the first echo image was significantly higher than those of 3D-FS-SPGR sequence, with CNR being 29.88 ± 10.00 vs 12.08 ± 3.08(t=23.09, P=0.000) and SNR being 34.70 ± 11.16 vs 14.18 ± 3.46(t=23.929, P=0.000).②The mean T1ρvalue of the superficial layer [(43.23 ± 6.78) ms] was significantly higher than that of the deep layer[(29.12 ± 8.07) ms](t=-24.687, P=0 .000). Conclusion It is demonstrated that T1ρsequence could be used for clinical evaluation of cartilage, and the collagen fiber is arranged more closely in the superficial layer than in the deep layer.%目的:比较正常膝关节软骨MRI T1ρ和三

  14. Dynamic contrast enhanced T1 MRI perfusion differentiates pseudoprogression from recurrent glioblastoma.

    Science.gov (United States)

    Thomas, Alissa A; Arevalo-Perez, Julio; Kaley, Thomas; Lyo, John; Peck, Kyung K; Shi, Weiji; Zhang, Zhigang; Young, Robert J

    2015-10-01

    Pseudoprogression may present as transient new or increasing enhancing lesions that mimic recurrent tumors in treated glioblastoma. The purpose of this study was to examine the utility of dynamic contrast enhanced T1 magnetic resonance imaging (DCE MRI) in differentiating between pseudoprogression and tumor progression and devise a cut-off value sensitive for pseudoprogression. We retrospectively examined 37 patients with glioblastoma treated with radiation and temozolomide after surgical resection that then developed new or increasing enhancing lesion(s) indeterminate for pseudoprogression versus progression. Volumetric plasma volume (Vp) and time-dependent leakage constant (Ktrans) maps were measured for the enhancing lesion and the mean and ninetieth percentile histogram values recorded. Lesion outcome was determined by clinical follow up with pseudoprogression defined as stable disease not requiring new treatment. Statistical analysis was performed with Wilcoxon rank-sum tests. Patients with pseudoprogression (n = 13) had Vp (mean) = 2.4 and Vp (90 %tile) = 3.2; and Ktrans (mean) = 3.5 and Ktrans (90 %tile) = 4.2. Patients with tumor progression (n = 24) had Vp (mean) = 5.3 and Vp (90 %tile) = 6.6; and Ktrans (mean) = 7.4 and Ktrans (90 %tile) = 9.1. Compared with tumor progression, pseudoprogression demonstrated lower Vp perfusion values (p = 0.0002) with a Vp (mean) cutoff mean) of >3.6 had a 69% sensitivity and 79% specificity for disease progression. DCE MRI shows lower plasma volume and time dependent leakage constant values in pseudoprogression than in tumor progression. A cut-off value with high sensitivity for pseudoprogression can be applied to aid in interpretation of DCE MRI.

  15. Comparison of accelerated T1-weighted whole-brain structural-imaging protocols.

    Science.gov (United States)

    Falkovskiy, Pavel; Brenner, Daniel; Feiweier, Thorsten; Kannengiesser, Stephan; Maréchal, Bénédicte; Kober, Tobias; Roche, Alexis; Thostenson, Kaely; Meuli, Reto; Reyes, Denise; Stoecker, Tony; Bernstein, Matt A; Thiran, Jean-Philippe; Krueger, Gunnar

    2016-01-01

    Imaging in neuroscience, clinical research and pharmaceutical trials often employs the 3D magnetisation-prepared rapid gradient-echo (MPRAGE) sequence to obtain structural T1-weighted images with high spatial resolution of the human brain. Typical research and clinical routine MPRAGE protocols with ~1mm isotropic resolution require data acquisition time in the range of 5-10min and often use only moderate two-fold acceleration factor for parallel imaging. Recent advances in MRI hardware and acquisition methodology promise improved leverage of the MR signal and more benign artefact properties in particular when employing increased acceleration factors in clinical routine and research. In this study, we examined four variants of a four-fold-accelerated MPRAGE protocol (2D-GRAPPA, CAIPIRINHA, CAIPIRINHA elliptical, and segmented MPRAGE) and compared clinical readings, basic image quality metrics (SNR, CNR), and automated brain tissue segmentation for morphological assessments of brain structures. The results were benchmarked against a widely-used two-fold-accelerated 3T ADNI MPRAGE protocol that served as reference in this study. 22 healthy subjects (age=20-44yrs.) were imaged with all MPRAGE variants in a single session. An experienced reader rated all images of clinically useful image quality. CAIPIRINHA MPRAGE scans were perceived on average to be of identical value for reading as the reference ADNI-2 protocol. SNR and CNR measurements exhibited the theoretically expected performance at the four-fold acceleration. The results of this study demonstrate that the four-fold accelerated protocols introduce systematic biases in the segmentation results of some brain structures compared to the reference ADNI-2 protocol. Furthermore, results suggest that the increased noise levels in the accelerated protocols play an important role in introducing these biases, at least under the present study conditions. Copyright © 2015 Elsevier Inc. All rights reserved.

  16. Detection of Lesions Underlying Intractable Epilepsy on T1-Weighted MRI as an Outlier Detection Problem

    Science.gov (United States)

    El Azami, Meriem; Hammers, Alexander; Jung, Julien; Costes, Nicolas; Bouet, Romain; Lartizien, Carole

    2016-01-01

    Pattern recognition methods, such as computer aided diagnosis (CAD) systems, can help clinicians in their diagnosis by marking abnormal regions in an image. We propose a machine learning system based on a one-class support vector machine (OC-SVM) classifier for the detection of abnormalities in magnetic resonance images (MRI) applied to patients with intractable epilepsy. The system learns the features associated with healthy control subjects, allowing a voxelwise assessment of the deviation of a test subject pattern from the learned patterns. While any number of various features can be chosen and learned, here we focus on two texture parameters capturing image patterns associated with epileptogenic lesions on T1-weighted brain MRI e.g. heterotopia and blurred junction between the grey and white matter. The CAD output consists of patient specific 3D maps locating clusters of suspicious voxels ranked by size and degree of deviation from control patterns. System performance was evaluated using realistic simulations of challenging detection tasks as well as clinical data of 77 healthy control subjects and of eleven patients (13 lesions). It was compared to that of a mass univariate statistical parametric mapping (SPM) single subject analysis based on the same set of features. For all simulations, OC-SVM yielded significantly higher values of the area under the ROC curve (AUC) and higher sensitivity at low false positive rate. For the clinical data, both OC-SVM and SPM successfully detected 100% of the lesions in the MRI positive cases (3/13). For the MRI negative cases (10/13), OC-SVM detected 7/10 lesions and SPM analysis detected 5/10 lesions. In all experiments, OC-SVM produced fewer false positive detections than SPM. OC-SVM may be a versatile system for unbiased lesion detection. PMID:27603778

  17. Anticonvulsant activity of artificial sweeteners: a structural link between sweet-taste receptor T1R3 and brain glutamate receptors.

    Science.gov (United States)

    Talevi, Alan; Enrique, Andrea V; Bruno-Blanch, Luis E

    2012-06-15

    A virtual screening campaign based on application of a topological discriminant function capable of identifying novel anticonvulsant agents indicated several widely-used artificial sweeteners as potential anticonvulsant candidates. Acesulfame potassium, cyclamate and saccharin were tested in the Maximal Electroshock Seizure model (mice, ip), showing moderate anticonvulsant activity. We hypothesized a probable structural link between the receptor responsible of sweet taste and anticonvulsant molecular targets. Bioinformatic tools confirmed a highly significant sequence-similarity between taste-related protein T1R3 and several metabotropic glutamate receptors from different species, including glutamate receptors upregulated in epileptogenesis and certain types of epilepsy.

  18. Intraindividual comparison of T1 relaxation times after gadobutrol and Gd-DTPA administration for cardiac late enhancement imaging

    Energy Technology Data Exchange (ETDEWEB)

    Doeblin, Patrick, E-mail: Patrick.doeblin@charite.de [Department of Cardiology, Charité – Universitätsmedizin Berlin, Charité Campus Benjamin Franklin, Berlin (Germany); Schilling, Rene, E-mail: rene.schilling@charite.de [Department of Radiology, Charité – Universitätsmedizin Berlin, Charité Campus Mitte, Berlin (Germany); Wagner, Moritz, E-mail: moritz.wagner@charite.de [Department of Radiology, Charité – Universitätsmedizin Berlin, Charité Campus Mitte, Berlin (Germany); Luhur, Reny, E-mail: renyluhur@yahoo.com [Department of Radiology, Charité – Universitätsmedizin Berlin, Charité Campus Mitte, Berlin (Germany); Huppertz, Alexander, E-mail: alexander.huppertz@charite.de [Department of Radiology, Charité – Universitätsmedizin Berlin, Charité Campus Mitte, Berlin (Germany); Imaging Science Institute, Charité, Berlin (Germany); Hamm, Bernd, E-mail: bernd.hamm@charite.de [Department of Radiology, Charité – Universitätsmedizin Berlin, Charité Campus Mitte, Berlin (Germany); Taupitz, Matthias, E-mail: matthias.taupitz@harite.de [Department of Radiology, Charité – Universitätsmedizin Berlin, Charité Campus Mitte, Berlin (Germany); and others

    2014-04-15

    Purpose: To evaluate T1-relaxation times of chronic myocardial infarction (CMI) using gadobutrol and gadopentetate dimeglumine (Gd-DTPA) over time and to determine the optimal imaging window for late enhancement imaging with both contrast agents. Material and methods: Twelve patients with CMI were prospectively included and examined on a 1.5 T magnetic resonance (MR) system using relaxivity-adjusted doses of gadobutrol (0.15 mmol/kg) and Gd-DTPA (0.2 mmol/kg) in random order. T1-relaxation times of remote myocardium (RM), infarcted myocardium (IM), and left ventricular cavity (LVC) were assessed from short-axis TI scout imaging using the Look–Locker approach and compared intraindividually using a Wilcoxon paired signed-rank test (α < 0.05). Results: Within 3 min of contrast agent administration (CA), IM showed significantly lower T1-relaxation times than RM with both contrast agents, indicating beginning cardiac late enhancement. Differences between gadobutrol and Gd-DTPA in T1-relaxation times of IM and RM were statistically not significant through all time points. However, gadobutrol led to significantly higher T1-relaxation times of LVC than Gd-DTPA from 6 to 9 min (220 ± 15 ms vs. 195 ± 30 ms p < 0.01) onwards, resulting in a significantly greater ΔT1 of IM to LVC at 9–12 min (−20 ± 35 ms vs. 0 ± 35 ms, p < 0.05) and 12–15 min (−25 ± 45 ms vs. −10 ± 60 ms, p < 0.05). Using Gd-DTPA, comparable ΔT1 values were reached only after 25–35 min. Conclusion: This study indicates good delineation of IM to RM with both contrast agents as early as 3 min after administration. However, we found significant differences in T1 relaxation times with greater ΔT1 IM–LVC using 0.15 mmol/kg gadobutrol compared to 0.20 mmol/kg Gd-DTPA after 9–15 min post-CA suggesting earlier differentiability of IM and LVC using gadobutrol.

  19. Electrically-assisted delivery of an anionic protein across intact skin: cathodal iontophoresis of biologically active ribonuclease T1.

    Science.gov (United States)

    Dubey, S; Kalia, Y N

    2011-06-30

    Cathodal iontophoresis of anionic macromolecules has been considered a major challenge owing to (i) the presence of a negative charge on the skin under physiological conditions and (ii) the electroosmotic solvent flow in the (opposite) anode-to-cathode direction. Moreover, electroosmosis, and not electromigration, was considered as the likely electrotransport mechanism for high molecular weight cations. However, it was recently shown that electromigration governed anodal iontophoretic transport of Cytochrome c (12.4 kDa) and Ribonuclease A (RNAse A; 13.6 kDa). Thus, the objective of this study was to investigate the feasibility of iontophoresing a negatively charged protein, the enzyme Ribonuclease T1 (RNAse T1, 11.1 kDa), from the cathode across intact skin. Cumulative permeation and skin deposition of RNAse T1 were investigated as a function of current density (0.15, 0.3 and 0.5 mA/cm(2) applied for 8h) using porcine ear skin and quantified by an enzymatic activity assay. Although RNAse T1 permeation was dependent upon current density (22.41 ± 8.10, 76.41 ± 56.98 and 142.19 ± 62.23μg/cm(2), respectively), no such relationship was observed with respect to skin deposition (9.78 ± 2.39, 7.76 ± 4.34 and 8.70 ± 2.94 μg/cm(2), respectively). MALDI-TOF spectra and the activity assay confirmed that RNAse T1 retained structural integrity and enzymatic function post-iontophoresis. Acetaminophen iontophoresis demonstrated the anode-to-cathode directionality of electroosmotic solvent flow confirming that RNAse T1 electrotransport was due entirely to electromigration. Interestingly, despite its lower net charge and higher molecular weight, electromigration of cationic Ribonuclease A was superior to that of RNAse T1 after iontophoresis at 0.5 mA/cm(2) for 8h. These results provide further evidence that charge to mass ratio and hence electric mobility might not alone be sufficient to predict protein electrotransport across the skin; three dimensional structures and the

  20. Characterization of myocardial T1-mapping bias caused by intramyocardial fat in inversion recovery and saturation recovery techniques.

    Science.gov (United States)

    Kellman, Peter; Bandettini, W Patricia; Mancini, Christine; Hammer-Hansen, Sophia; Hansen, Michael S; Arai, Andrew E

    2015-05-10

    Quantitative measurement of T1 in the myocardium may be used to detect both focal and diffuse disease processes such as interstitial fibrosis or edema. A partial volume problem exists when a voxel in the myocardium also contains fat. Partial volume with fat occurs at tissue boundaries or within the myocardium in the case of lipomatous metaplasia of replacement fibrosis, which is commonly seen in chronic myocardial infarction. The presence of fat leads to a bias in T1 measurement. The mechanism for this artifact for widely used T1 mapping protocols using balanced steady state free precession readout and the dependence on off-resonance frequency are described in this paper. Simulations were performed to illustrate the behavior of mono-exponential fitting to bi-exponential mixtures of myocardium and fat with varying fat fractions. Both inversion recovery and saturation recovery imaging protocols using balanced steady state free precession are considered. In-vivo imaging with T1-mapping, water/fat separated imaging, and late enhancement imaging was performed on subjects with chronic myocardial infarction. In n = 17 subjects with chronic myocardial infarction, lipomatous metaplasia is evident in 8 patients (47%). Fat fractions as low as 5% caused approximately 6% T1 elevation for the out-of-phase condition, and approximately 5% reduction of T1 for the in-phase condition. T1 bias in excess of 1000 ms was observed in lipomatous metaplasia with fat fraction of 38% in close agreement with simulation of the specific imaging protocols. Measurement of the myocardial T1 by widely used balanced steady state free precession mapping methods is subject to bias when there is a mixture of water and fat in the myocardium. Intramyocardial fat is frequently present in myocardial scar tissue due lipomatous metaplasia, a process affecting myocardial infarction and some non-ischemic cardiomyopathies. In cases of lipomatous metaplasia, the T1 biases will be additive or subtractive

  1. Water Supply System Maintenance of the T1 Terminal of Shanghai Pudong International Airport%上海浦东国际机场T1航站楼给水系统维护

    Institute of Scientific and Technical Information of China (English)

    杨居川

    2015-01-01

    In the work of energy supply for the terminal during these years, water supply system security played a crucial role. In order to ensure the normal operation of the water supply system of the T1 terminal in the future, the water supply system was evaluated combining with field investigation. This evaluation especially studied the composition of water supply system, the equipment characteristics and current operation situation. Through the comparison between original design and current situation, this evaluation also discussed whether the current water supply system could meet the current and future requirement. Meanwhile , this evaluation tested the lifetime of the main equipment and explained the existing deficiencies of the water supply system. This article would provide reference suggestions to the operation and maintenance of the water supply system of the T1 terminal of Shanghai Pudong International Airport in the future.%为确保上海浦东国际机场T1航站楼给水系统将来的正常运行,结合现场调研情况对T1航站楼给水系统进行了分析评估,重点研究了T1航站楼给水系统的构成、设备的性能及运载状况,并通过与原始设计资料的对比分析,探讨系统运行状况是否满足现状要求和未来需求;同时,评估了主要设备使用寿命,阐述了设备系统存在的不足,以期为T1航站楼给水系统设备未来的运行维护提供参考建议。

  2. T1-weighted vs. short-TE-long-TR images. Usefulness for knee MR examinations of ligament and meniscal lesions

    Energy Technology Data Exchange (ETDEWEB)

    Endo, Hideho; Wada, Mitsuyoshi; Shiotani, Seiji [Tsukuba Medical Center Hospital, Ibaraki (Japan); Niitsu, Mamoru; Itai, Yuji

    2000-11-01

    The purpose of this study was to compare short-TE-long-TR images with T1-weighed images in knee MR examinations. Sagittal MR images of the knee were obtained in 31 patients with knee pain. T1-weighted images were obtained by the spin-echo technique (TR/TE =350/15), and short-TE-long-TR images by fast spin-echo (TR/TE =1300/15) with an echo-train length of 5. Contrast-to-noise-ratios (CNRs) of the anterior cruciate ligament and synovial space, meniscus and articular cartilage, and meniscal lesion and normal meniscus were compared between short-TE-long-TR images and T1-weighted images. On each of the three examinations, short-TE-long-TR images provided significantly higher CNRs than T1-weighted images. It was concluded that short-TE-long-TR images can be a useful alternative to T1-weighted images in evaluating the anterior cruciate ligament and meniscal lesions. (author)

  3. Tumor microcirculation during a course of combined chemoradiation in patients with primary rectal carcinoma measured with dynamic T1 mapping

    Science.gov (United States)

    Kremser, Christian; Judmaier, Werner; De Vries, Alexander

    2003-05-01

    A recently introduced dynamic T1 mapping technique was used to investigate changes of tumor microcirculatory parameters in 16 patients with clinically staged T3) primary rectal carcinoma during a course of preoperative combined chemoradiation. For dynamic T1 mapping an ultra-fast snapshot FLASH T1 mapping sequence was implemented on a 1.5T whole body MR scanner. Acquiring a series of T1 maps contrast media (CM) uptake and washout over an examination time of 40 min was monitored. From the obtained series of T1-maps perfusion-indices (PI) were calculated as the ratio of maximum slope of the tumor CM curve and the maximum of the arterial CM curve. Using pathologic classification of the resected tumors after therapy the patient group could be divided into patients with and without response to therapy. It was found that mean pre-therapy PI values of tumors showing therapy-response were significantly lower than for tumors without no therapy-response. In addition a different behavior of PI distributions within tumors for both groups was observed. The presented study indicates that PI values and their distributions within a tumor seem to be of predictive value for therapy outcome of preoperative therapy in patients with primary rectal carcinoma.

  4. Translational downregulation of the noncatalytic growth factor receptor TrkB.T1 by ischemic preconditioning of primary neurons.

    Science.gov (United States)

    Steinbeck, Julius A; Methner, Axel

    2005-01-01

    Short episodes of ischemia can protect neuronal cells and tissue against a subsequent lethal ischemia by a phenomenon called ischemic preconditioning. The development of this tolerance depends on protein synthesis and takes at least 1 day. It therefore seems reasonable that preconditioning leads to upregulation and translation of protective genes or posttranslational modification of pro- or antiapoptotic proteins. We recently used suppression subtractive hybridization to identify transcripts upregulated in rat primary neuronal cultures preconditioned by oxygen glucose deprivation. In this contribution, we describe the previously unknown 7-kb full-length sequence of an upregulated expressed sequence tag and show that it constitutes the 3' end of the large untranslated region of the noncatalytic "truncated" growth factor receptor TrkB.T1. TrkB.T1 is expressed most prominently in the adult brain and its mRNA was found to be 2.1-fold upregulated by ischemic preconditioning. At the protein level, however, TrkB.T1 was clearly downregulated, possibly by increased degradation in preconditioned cultures. TrKB.T1 can act as a dominant-negative inhibitor of its catalytic counterpart TrkB, which is the receptor for brain-derived neurotrophic factor (BDNF), a factor induced by ischemia that can protect from ischemia-induced neuron loss. We hypothesize that the downregulation of TrkB.T1 at the protein level can prolong BDNF-mediated protective signaling via the catalytic receptor and thus participates in the development of ischemic preconditioning.

  5. Co-strengthening contribution of δ' and T1 precipitates in Al-Li alloys 2090 and 2090+Ce

    Institute of Scientific and Technical Information of China (English)

    ZHAO Zhilong; LIU Lin; CHEN Zheng

    2006-01-01

    The microstructure of dislocation in two kinds of aluminum-lithium alloys 2090 and 2090 + Ce was observed by means of TEM technology. The contributions of δ' and T1 precipitates to strength were separately calculated by using the results of quantitative metallography and analysis of micro-deformation behavior; the co-strengthening effect of δ' and T1precipitates was studied. The results show that the adding relationship of co-strengthening of δ' and T1 is in accordance with q = 1.4 form at the near peak-aged condition, i.e., △τ1.4 p = △τ1.4 δ' + △τ1.4 T1; but the adding relationship is approximately a linear relation (q = 1) at the under-aged condition and becomes the parabola form when over-aged (q = 2). The adding relationship of co-strengthening contribution of δ' and T1 is obviously dependent on aging time.

  6. Combined T2 and T1 measurements for improved perfusion and permeability studies in high field using dynamic contrast enhancement

    Energy Technology Data Exchange (ETDEWEB)

    Bazelaire, Cedric de [Saint Louis Hospital, Radiology Department, Paris, Cedex 10 (France); Beth Israel Deaconess Medical Center and Harvard Medical School, Department of Radiology, Cambridge, MA (United States); Rofsky, Neil M.; Duhamel, Guillaume; Zhang, Jingbo; Alsop, David C. [Beth Israel Deaconess Medical Center and Harvard Medical School, Department of Radiology, Cambridge, MA (United States); Michaelson, M.D. [Massachusetts General Hospital, Department of Hematology/Oncology, Boston, MA (United States); George, Daniel [Dana Farber Cancer Institute, Department of Adult Oncology, Boston, MA (United States)

    2006-09-15

    This study analyzed the T2* effect of extracellularly distributed gadolinium contrast agents in arterial blood during tumor studies using T1-weighted sequences at high field strength. A saturation-prepared dual echo sequence with echo times of 1.5 and 3.5 ms was employed at 3 T to simultaneously characterize T1 and T2* of arterial blood during bolus administration of Gd-DTPA in 28 patients with body tumors. T2* effect and T1 effect of Gd-DTPA on image intensity of whole blood were calibrated in human blood samples with different concentrations of contrast agent. T2* was used to estimate concentration near the peak of the bolus. T1 was used to measure lower concentrations when T2* was not significant. T2* was measurable on calibration curves for Gd-DTPA concentrations higher than 4 mM. This concentration was exceeded in 18 patients. The mean signal intensity reduction because of T2* effect was estimated at 22{+-}14% of the T2* compensated signal. Using T2* measurements reduced underestimations of peak arterial Gd-DTPA concentration (59{+-}38%) and overestimation of permeability K{sup trans} (58%). The T2* effect of gadolinium contrast agents should therefore be accounted for when performing tumors study with T1-weighted sequences at high field strength. (orig.)

  7. The effects of proteoglycan and type II collagen on T1rho relaxation time of articular cartilage

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Won Seok; Yoo, Hye Jin; Hong, Sung Hwan; Choi, Ja Young [Dept. of Radiology and Institute of Radiation Medicine, Seoul National University Hospital, Seoul National University College of Medicine, Seoul (Korea, Republic of)

    2015-02-15

    To evaluate the effects of proteoglycan and type II collagen within articular cartilage on T1rho relaxation time of articular cartilage. This study was exempted by the institutional and animal review boards, and informed consent was not required. Twelve porcine patellae were assigned to three groups of control, trypsin-treated (proteoglycan-degraded), or collagenase-treated (collagen-degraded). The T1rho images were obtained with a 3 tesla magnetic resonance imaging scanner with a single loop coil. Statistical differences were detected by analysis of variance to evaluate the effects of the enzyme on T1rho relaxation time. Safranin-O was used to stain proteoglycan in the articular cartilage and immunohistochemical staining was performed for type II collagen. Mean T1rho values of the control, trypsin-treated, and collagenase-treated groups were 37.72 +/- 5.82, 57.53 +/- 8.24, and 45.08 +/- 5.31 msec, respectively (p < 0.001). Histology confirmed a loss of proteoglycan and type II collagen in the trypsin- and collagenase-treated groups. Degradation of proteoglycans and collagen fibers in the articular cartilage increased the articular cartilage T1rho value.

  8. Comparison among T1-Weighted Magnetic Resonance Imaging, Modified Dixon Method, and Magnetic Resonance Spectroscopy in Measuring Bone Marrow Fat

    Directory of Open Access Journals (Sweden)

    Wei Shen

    2013-01-01

    Full Text Available Introduction. An increasing number of studies are utilizing different magnetic resonance (MR methods to quantify bone marrow fat due to its potential role in osteoporosis. Our aim is to compare the measurements of bone marrow fat among T1-weighted magnetic resonance imaging (MRI, modified Dixon method (also called fat fraction MRI (FFMRI, and magnetic resonance spectroscopy (MRS. Methods. Contiguous MRI scans were acquired in 27 Caucasian postmenopausal women with a modified Dixon method (i.e., FFMRI. Bone marrow adipose tissue (BMAT of T1-weighted MRI and bone marrow fat fraction of the L3 vertebra and femoral necks were quantified using SliceOmatic and Matlab. MRS was also acquired at the L3 vertebra. Results. Correlation among the three MR methods measured bone marrow fat fraction and BMAT ranges from 0.78 to 0.88 in the L3 vertebra. Correlation between BMAT measured by T1-weighted MRI and bone marrow fat fraction measured by modified FFMRI is 0.86 in femoral necks. Conclusion. There are good correlations among T1-weighted MRI, FFMRI, and MRS for bone marrow fat quantification. The inhomogeneous distribution of bone marrow fat, the threshold segmentation of the T1-weighted MRI, and the ambiguity of the FFMRI may partially explain the difference among the three methods.

  9. Improved Temperature Measurement for Permanent MRI System by Using Hybrid PRF/T1 Method%一种在永磁MRI系统上利用混合PRF/T1的改进测温方法

    Institute of Scientific and Technical Information of China (English)

    王雷; 李璟; 朱剑锋; 钟智辉; 陈武凡; 冯衍秋

    2013-01-01

    研究基于混合PRF/T1的测温方法,以提高永磁MRI温度测量的准确度与可靠性.用琼脂凝胶仿真肝脏组织制作体模,将体模放在水浴中加热到65℃,然后置于0.3T永磁MRI系统用翻转角为40°与75°的梯度回波序列进行交替连续扫描,在降温中温度每下降1℃采集一次数据直到36℃.对所采集数据,分别用质子共振频率(PRF)方法、水质子纵向弛豫时间(T1)方法、改进的混合PRF/T1方法计算温度变化,并以酒精温度计测温结果作为参考.比较这3种方法的测温准确度,3d内分别进行3次测温实验,用3次实验结果的变异系数(COV)评价测温方法可重复性.结果表明,仅用PRF或T1方法的测温误差为±6℃,而改进的混合PRF/T1方法的测温误差为±3℃.PRF方法的COV=3.12%,T1方法的COV =7.53%,改进的混合PRF/L方法的COV =2.63%.在永磁MRI系统上采用改进的混合PRF/T1方法比单一用PRF或T1方法的测温准度高且可重复性好,可以更好的满足肿瘤热消融对温度监控的需求.

  10. The Ssr protein (T1E_1405) from Pseudomonas putida DOT-T1E enables oligonucleotide-based recombineering in platform strain P. putida EM42

    DEFF Research Database (Denmark)

    Aparicio, Tomás; Ingemann Jensen, Sheila; Nielsen, Alex Toftgaard

    2016-01-01

    of reference strain KT2440) is still a time-consuming endeavor. In this work we have investigated the in vivo activity of the Ssr protein encoded by the open reading frame T1E_1405 from Pseudomonas putida DOT-T1E, a plausible functional homologue of the β protein of the Red recombination system of λ phage...... of Escherichia coli. A test based on the phenotypes of pyrF mutants of P. putida (the yeast’s URA3 ortholog) was developed for quantifying the ability of Ssr to promote invasion of the genomic DNA replication fork by synthetic oligonucleotides. The efficiency of the process was measured by monitoring...

  11. [Prognostic differences of phenotypes in pT1-2N0 invasive breast cancer: a large cohort study with cluster analysis].

    Science.gov (United States)

    Wang, Z; Wang, W H; Wang, S L; Jin, J; Song, Y W; Liu, Y P; Ren, H; Fang, H; Tang, Y; Chen, B; Qi, S N; Lu, N N; Li, N; Tang, Y; Liu, X F; Yu, Z H; Li, Y X

    2016-06-23

    To find phenotypic subgroups of patients with pT1-2N0 invasive breast cancer by means of cluster analysis and estimate the prognosis and clinicopathological features of these subgroups. From 1999 to 2013, 4979 patients with pT1-2N0 invasive breast cancer were recruited for hierarchical clustering analysis. Age (≤40, 41-70, 70+ years), size of primary tumor, pathological type, grade of differentiation, microvascular invasion, estrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor 2 (HER-2) were chosen as distance metric between patients. Hierarchical cluster analysis was performed using Ward's method. Cophenetic correlation coefficient (CPCC) and Spearman correlation coefficient were used to validate clustering structures. The CPCC was 0.603. The Spearman correlation coefficient was 0.617 (Pcluster model seemed to best illustrate our patient cohort. Patients in cluster 5, 9 and 12 had best prognosis and were characterized by age >40 years, smaller primary tumor, lower histologic grade, positive ER and PR status, and mainly negative HER-2. Patients in the cluster 1 and 11 had the worst prognosis, The cluster 1 was characterized by a larger tumor, higher grade and negative ER and PR status, while the cluster 11 was characterized by positive microvascular invasion. Patients in other 7 clusters had a moderate prognosis, and patients in each cluster had distinctive clinicopathological features and recurrent patterns. This study identified distinctive clinicopathologic phenotypes in a large cohort of patients with pT1-2N0 breast cancer through hierarchical clustering and revealed different prognosis. This integrative model may help physicians to make more personalized decisions regarding adjuvant therapy.

  12. Diagnostic value of MRI on T1WI in injury of meniscus of knee joints%MRI扫描T1WI序列对膝关节半月板损伤的诊断价值

    Institute of Scientific and Technical Information of China (English)

    杨宇

    2013-01-01

    目的 探讨MRI扫描T1WI序列在显示膝关节半月板损伤中的价值.方法 回顾分析膝关节疼痛可疑半月板损伤患者80例,按内外侧半月板前后角分开计数,共计380例半月板,常规行T1WI序列、T2WI脂肪抑制序列扫描.将T1WI与T2WI脂肪抑制序列的影像进行对比.结果 T1WI序列共发现半月板损伤0级186例、Ⅰ级91例、Ⅱ级84例、Ⅲ级14例、Ⅳ级5例;T2WI脂肪抑制序列共发现半月板损伤0级225例、Ⅰ级61例、Ⅱ级75例、Ⅲ级14例、Ⅳ级5例.两组比较差异有统计学意义(P< 0.05).结论 T1WI序列在发现半月板Ⅰ级、Ⅱ级损伤上敏感性较好,对可疑半月板Ⅰ级和Ⅱ级损伤者可着重观察T1WI图像.%Objective To explore the value of MRI on T1WI in injury of meniscus of knee joints.Methods Retrospective analyses were conducted on 95 cases of patients with painful knee joints who were suspected to have meniscus injury.Counted seperately by lateral and medial meniscus as well as anterior and posterior angle,there were totally 380 menisci.T1WI sequence and fat suppressed sequence on T2WI were scanned and compared.Results The images on T1WI showed that 186 menisci were of level 0,91 of leve Ⅰ,84 of level Ⅱ,14 of level Ⅲ and 5 of level Ⅳ.The images on T2WI fat suppressed sequence indicated that 225 menisci were of level 0,61 of level Ⅰ,75 of level Ⅱ,14 of level Ⅲ and 5 of level Ⅳ.The differences between 2 groups had statistic significances (P<0.05).Conclusion T1WI sequence is more sensitive to show the leve Ⅰ and level Ⅱ injury of meniscus.The suspicious leve Ⅰ and level Ⅱ of meniscal lesions are highly recommended to be observed in T1WI images.

  13. Characterization of myocardial T1-mapping bias caused by intramyocardial fat in inversion recovery and saturation recovery techniques

    DEFF Research Database (Denmark)

    Kellman, Peter; Bandettini, W Patricia; Mancini, Christine

    2015-01-01

    precession readout and the dependence on off-resonance frequency are described in this paper. METHODS: Simulations were performed to illustrate the behavior of mono-exponential fitting to bi-exponential mixtures of myocardium and fat with varying fat fractions. Both inversion recovery and saturation recovery......BACKGROUND: Quantitative measurement of T1 in the myocardium may be used to detect both focal and diffuse disease processes such as interstitial fibrosis or edema. A partial volume problem exists when a voxel in the myocardium also contains fat. Partial volume with fat occurs at tissue boundaries...... or within the myocardium in the case of lipomatous metaplasia of replacement fibrosis, which is commonly seen in chronic myocardial infarction. The presence of fat leads to a bias in T1 measurement. The mechanism for this artifact for widely used T1 mapping protocols using balanced steady state free...

  14. Various ligand-coated ultrasmall gadolinium-oxide nanoparticles: Water proton relaxivity and in-vivo T1 MR image

    Science.gov (United States)

    Park, Ja Young; Kim, Sung June; Lee, Gang Ho; Jin, Seonguk; Chang, Yongmin; Bae, Ji Eun; Chae, Kwon Seok

    2015-04-01

    Surface coating of nanoparticles with ligands is essential in magnetic resonance imaging (MRI) because of solubility in water and biocompatibility. In this study, five organic molecules were used for surface coating of ultrasmall gadolinium-oxide (Gd2O3) nanoparticles (d avg = 2.0 nm). All of the samples showed large longitudinal (r1) and transverse (r2) water proton relaxivities with r2/r1 ratios that were close to one, corresponding to ideal conditions for T1 MRI contrast agents. Finally, in-vivo T1 MR images were acquired to prove the effectiveness of the surface-coated ultrasmall Gd2O3 nanoparticles as a T1 MRI contrast agent.

  15. Dynamic contrast-enhanced quantitative perfusion measurement of the brain using T-1-weighted MRI at 3T

    DEFF Research Database (Denmark)

    Larsson, H.B.W.; Hansen, A.E.; Berg, H.K.;

    2008-01-01

    Purpose: To develop a method for the measurement of brain perfusion based on dynamic contrast-enhanced T-1-weighted MR imaging. Materials and Methods: Dynamic imaging of the first pass of a bolus of a paramagnetic contrast agent was performed using a 3T whole-body magnet and a T-1-weighted fast...... field echo sequence. The input function was obtained from the internal carotid artery. An initial T-1 measurement was performed in order to convert the MR signal to concentration of the contrast agent. Pixelwise and region of interest (ROI)based calculation of cerebral perfusion (CBF) was performed...... inside the infarct core was, 9 mL/100g/min in one of the stroke patients. The other stroke patient had postischemic hyperperfusion and CBF was 140 mL/100g/min. Conclusion: Absolute values of brain perfusion can be obtained using dynamic contrast-enhanced MRI. These values correspond,to expected values...

  16. The Culture of Pediococcus pentosaceus T1 Inhibits Listeria Proliferation in Salmon Fillets and Controls Maturation of Kimchi

    Directory of Open Access Journals (Sweden)

    Seongho Jang

    2015-01-01

    Full Text Available The objective of this study is to evaluate the antilisterial effect of Pediococcus pentosaceus T1, which was isolated from kimchi, and to assess its potential for extending the shelf life of salmon and kimchi. Pediococcus pentosaceus T1 culture eff ectively inhibited proliferation of Listeria monocytogenes in a dose-dependent manner in a salmon-based medium. Antilisterial effect of the culture was stronger than that of nisin, an antibacterial peptide, as evidenced by lower minimum inhibitory concentration value (20 mg/mL compared to nisin (over 20 mg/mL. P. pentosaceus T1 culture also effectively inhibited the growth of Listeria in salmon fi llet. In particular, the culture (6 g per 100 mL showed a stronger inhibitory effect than sodium hypochlorite (0.2 mg/mL, a disinfectant used in food processing. In kimchi fermentation, the treatment with P. pentosaceus T1 culture suppressed changes of acidity and pH during maturation. The inhibitory eff ect of the culture on kimchi lactic acid bacteria, which include Leuconostoc mesenteroides and Lactobacillus sakei, led to a drastic decrease in maturation rates of kimchi. Moreover, sensory test on kimchi treated with P. pentosaceus T1 showed that the culture improved overall acceptability of kimchi, which can be observed in higher scores of sourness, texture, off-flavour and mouthfeel compared with untreated kimchi. The results of this study suggest that kimchi-derived P. pentosaceus T1 could be a potential antilisterial agent in fi sh products as well as a starter to control overmaturation of kimchi.

  17. GST M1-T1 null allele frequency patterns in geographically assorted human populations: a phylogenetic approach.

    Science.gov (United States)

    Kasthurinaidu, Senthilkumar Pitchalu; Ramasamy, Thirumurugan; Ayyavoo, Jayachitra; Dave, Dhvani Kirtikumar; Adroja, Divya Anantray

    2015-01-01

    Genetic diversity in drug metabolism and disposition is mainly considered as the outcome of the inter-individual genetic variation in polymorphism of drug-xenobiotic metabolizing enzyme (XME). Among the XMEs, glutathione-S-transferases (GST) gene loci are an important candidate for the investigation of diversity in allele frequency, as the deletion mutations in GST M1 and T1 genotypes are associated with various cancers and genetic disorders of all major Population Affiliations (PAs). Therefore, the present population based phylogenetic study was focused to uncover the frequency distribution pattern in GST M1 and T1 null genotypes among 45 Geographically Assorted Human Populations (GAHPs). The frequency distribution pattern for GST M1 and T1 null alleles have been detected in this study using the data derived from literatures representing 44 populations affiliated to Africa, Asia, Europe, South America and the genome of PA from Gujarat, a region in western India. Allele frequency counting for Gujarat PA and scattered plot analysis for geographical distribution among the PAs were performed in SPSS-21. The GST M1 and GST T1 null allele frequencies patterns of the PAs were computed in Seqboot, Gendist program of Phylip software package (3.69 versions) and Unweighted Pair Group method with Arithmetic Mean in Mega-6 software. Allele frequencies from South African Xhosa tribe, East African Zimbabwe, East African Ethiopia, North African Egypt, Caucasian, South Asian Afghanistan and South Indian Andhra Pradesh have been identified as the probable seven patterns among the 45 GAHPs investigated in this study for GST M1-T1 null genotypes. The patternized null allele frequencies demonstrated in this study for the first time addresses the missing link in GST M1-T1 null allele frequencies among GAHPs.

  18. GST M1-T1 null allele frequency patterns in geographically assorted human populations: a phylogenetic approach.

    Directory of Open Access Journals (Sweden)

    Senthilkumar Pitchalu Kasthurinaidu

    Full Text Available Genetic diversity in drug metabolism and disposition is mainly considered as the outcome of the inter-individual genetic variation in polymorphism of drug-xenobiotic metabolizing enzyme (XME. Among the XMEs, glutathione-S-transferases (GST gene loci are an important candidate for the investigation of diversity in allele frequency, as the deletion mutations in GST M1 and T1 genotypes are associated with various cancers and genetic disorders of all major Population Affiliations (PAs. Therefore, the present population based phylogenetic study was focused to uncover the frequency distribution pattern in GST M1 and T1 null genotypes among 45 Geographically Assorted Human Populations (GAHPs. The frequency distribution pattern for GST M1 and T1 null alleles have been detected in this study using the data derived from literatures representing 44 populations affiliated to Africa, Asia, Europe, South America and the genome of PA from Gujarat, a region in western India. Allele frequency counting for Gujarat PA and scattered plot analysis for geographical distribution among the PAs were performed in SPSS-21. The GST M1 and GST T1 null allele frequencies patterns of the PAs were computed in Seqboot, Gendist program of Phylip software package (3.69 versions and Unweighted Pair Group method with Arithmetic Mean in Mega-6 software. Allele frequencies from South African Xhosa tribe, East African Zimbabwe, East African Ethiopia, North African Egypt, Caucasian, South Asian Afghanistan and South Indian Andhra Pradesh have been identified as the probable seven patterns among the 45 GAHPs investigated in this study for GST M1-T1 null genotypes. The patternized null allele frequencies demonstrated in this study for the first time addresses the missing link in GST M1-T1 null allele frequencies among GAHPs.

  19. Prognostic Significance of Remote Myocardium Alterations Assessed by Quantitative Noncontrast T1 Mapping in ST-Segment Elevation Myocardial Infarction.

    Science.gov (United States)

    Reinstadler, Sebastian J; Stiermaier, Thomas; Liebetrau, Johanna; Fuernau, Georg; Eitel, Charlotte; de Waha, Suzanne; Desch, Steffen; Reil, Jan-Christian; Pöss, Janine; Metzler, Bernhard; Lücke, Christian; Gutberlet, Matthias; Schuler, Gerhard; Thiele, Holger; Eitel, Ingo

    2017-06-09

    This study assessed the prognostic significance of remote zone native T1 alterations for the prediction of clinical events in a population with ST-segment elevation myocardial infarction (STEMI) who were treated by primary percutaneous coronary intervention (PPCI) and compared it with conventional markers of infarct severity. The exact role and incremental prognostic relevance of remote myocardium native T1 mapping alterations assessed by cardiac magnetic resonance (CMR) after STEMI remains unclear. We included 255 consecutive patients with STEMI who were reperfused within 12 h after symptom onset. CMR core laboratory analysis was performed to assess left ventricular (LV) function, standard infarct characteristics, and native T1 values of the remote, noninfarcted myocardium. The primary endpoint was a composite of death, reinfarction, and new congestive heart failure within 6 months (major adverse cardiac events [MACE]). Patients with increased remote zone native T1 values (>1,129 ms) had significantly larger infarcts (p = 0.012), less myocardial salvage (p = 0.002), and more pronounced LV dysfunction (p = 0.011). In multivariable analysis, remote zone native T1 was independently associated with MACE after adjusting for clinical risk factors (p = 0.001) or other CMR variables (p = 0.007). In C-statistics, native T1 of remote myocardium provided incremental prognostic information beyond clinical risk factors, LV ejection fraction, and other markers of infarct severity (all p infarct size, and myocardial salvage index) led to net reclassification improvement of 0.82 (95% confidence interval: 0.46 to 1.17; p Myocardial Damage in STEMI [LIPSIA-COND]; NCT02158468). Copyright © 2017 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

  20. The influence of the level of lamina propria invasion and the prevalence of p53 nuclear accumulation on survival in stage T1 transitional cell bladder cancer

    DEFF Research Database (Denmark)

    Hermann, G G; Horn, T; Steven, K

    1998-01-01

    related to age, level of lamina propria invasion and presence of p53 nuclear accumulation. For this subpopulation overall survival was 67%, and 79% for stage T1a, 70% for stage T1b and 57% for stage T1c (p positive (61......PURPOSE: We assessed the influence of the level of lamina propria invasion and the prevalence of p53 nuclear immunoreactivity on the survival of patients with stage T1 transitional cell bladder cancer. MATERIALS AND METHODS: All patients presenting with stage T1 bladder cancer were prospectively...... and routinely grouped according to the level of lamina propria invasion. Invasion of the tumor stalk was defined as stage T1a, invasion of the lamina propria proper superficial to the level of muscularis mucosa as stage T1b and into or deeper than the muscularis mucosa as stage T1c. The p53 nuclear...

  1. Robotic partial nephrectomy for clinical stage T1 tumors: Experience in 42 cases

    Directory of Open Access Journals (Sweden)

    Kemal Ener

    2016-01-01

    Full Text Available The aim of this study was to evaluate outcomes of robotic partial nephrectomy (RAPN procedures. At two centers, 42 patients underwent RAPN. Radius, Exo/Endophytic, Nearness, Anterior/Posterior, Location (R.E.N.A.L. nephrometry and PADUA scores of patients were calculated by computed tomography (CT or magnetic resonance imaging (MRI. Intra- and perioperative (0–30 days complications were evaluated using modified Clavien classification. A four-arm da Vinci-S robotic surgical system was used and outcomes were evaluated retrospectively. Mean age of the patients was 52.3 ± 6.5 years. Mean tumor size was 3.1 ± 1.0 (1.4–6.6 cm. R.E.N.A.L. nephrometry and PADUA scores were 6.0 ± 1.5 and 7.5 ± 0.9, respectively. Mean surgical time was 127.7 ± 18.7 minutes and estimated blood loss was 100 ± 18.1 cc. Mean warm ischemia time was 16.0 ± 8.9 (0–30 minutes. Intraoperative complications did not develop in any patient. Median hospital stay was 3.0 (2–6 days. Except for 17 patients, hilar clamping was performed in 25 patients. Histopathology results included 34 renal cell carcinoma (22 clear cell, 7 chromophobe cell, 4 papillary cell, and 1 clear papillary cell. Oncocytoma (n = 4, adenoma (n = 1, fibroadipose tissue (n = 1, papillary epithelial hyperplasia (n = 1, and chronic pyelonephritis (n = 1 were present. Surgical margins were negative in all patients. During a median follow-up period of 15.5 ± 10.9 (3–46 months, neither local recurrence nor distant metastasis was detected. In conclusion, RAPN is a safe, minimally invasive surgical approach, with excellent surgical and oncological outcomes in T1 kidney tumors. Zero ischemia off-clamp RAPN is also safe in selected masses with the advantage of avoiding complete renal ischemia.

  2. T1 Recovery Is Predominantly Found in Black Holes and Is Associated with Clinical Improvement in Patients with Multiple Sclerosis.

    Science.gov (United States)

    Thaler, C; Faizy, T D; Sedlacik, J; Holst, B; Stürner, K; Heesen, C; Stellmann, J-P; Fiehler, J; Siemonsen, S

    2017-02-01

    Quantitative MR imaging parameters help to evaluate disease progression in multiple sclerosis and increase correlation with clinical disability. We therefore hypothesized that T1 values might be a marker for ongoing tissue damage or even remyelination and may help increase clinical correlation. MR imaging was performed in 17 patients with relapsing-remitting MS at baseline and after 12 months of starting immunotherapy with dimethyl fumarate. On baseline images, lesion segmentation was performed for normal-appearing white matter, T2 hyperintense (FLAIR lesions), T1 hypointense (black holes), and contrast-enhancing lesions, and T1 relaxation times were obtained at baseline and after 12 months. Changes in clinical status were assessed by using the Expanded Disability Status Scale and Symbol Digit Modalities Test at both dates (Expanded Disability Status Scale-difference/Symbol Digit Modalities Test-diff). The highest T1 relaxation time at baseline was measured in black holes (1460.2 ± 209.46 ms) followed by FLAIR lesions (1400.38 ± 189.1 ms), pure FLAIR lesions (1327.5 ± 210.04 ms), contrast-enhancing lesions (1205.59 ± 199.95 ms), and normal-appearing white matter (851.34 ± 30.61 ms). After 12 months, T1 values had decreased significantly in black holes (1369.4 ± 267.81 ms), contrast-enhancing lesions (1079.57 ± 183.36 ms) (both P < .001), and normal-appearing white matter (841.98 ± 36.1 ms, P = .006). With the Jonckheere-Terpstra Test, better clinical scores were associated with decreasing T1 relaxation times in black holes (P < .05). T1 relaxation time is a useful quantitative MR imaging technique, which helps detect changes in MS lesions with time. We assume that these changes are associated with the degree of myelination within the lesions themselves and are pronounced in black holes. Additionally, decreasing T1 values in black holes were associated with clinical improvement. © 2017 by American Journal of Neuroradiology.

  3. [Prognostic value of dynamic monitoring of RUNX1-RUNX1T1 transcript in pediatric acute myeloid leukemia].

    Science.gov (United States)

    Gao, H T; Zhang, Y; Sun, K; Guo, J M; Chen, Y Q; Chen, X L; Shi, J; Niu, X N; Wang, F; Huo, L

    2017-03-14

    Objective: To investigate the prognostic value of dynamic monitoring of RUNX1-RUNX1T1 transcript in pediatric patients with t (8;21) acute myeloid leukemia (AML) . Methods: The clinical features and RUNX1-RUNX1T1 transcript levels of 55 pediatric t (8;21) AML patients, newly diagnosed from Jan. 2010 to Apr. 2016, were analyzed retrospectively. The relationship between the minimal residual disease (MRD) and prognosis was analysed by dynamic monitoring of RUNX1-RUNX1T1 transcript levels using real-time quantitative PCR (RQ-PCR) technology. Results: The RUNX1-RUNX1T1 transcript levels in bone marrow cells at diagnosis was not related to relapse. After one course of induction therapy, patients with a more than 2 Log reduction of RUNX1-RUNX1T1 transcript levels (>2 Log) had lower 5 years cumulative incidence of relapse (CIR) [ (24.3±8.4) % vs (52.6±9.7) %, χ(2)=9.046, P=0.003], relapse-free survival (RFS) [ (71.6±12.7) % vs (48.1±13.2) %, χ(2)=5.814, P=0.016], and better overall survival (OS) [ (76.9±12.5) % vs (48.9±14.7) %, χ(2)=6.346, P=0.012], compared to patients with a less than 2 Log reduction (a2 Log reduction in RUNX1-RUNX1T1 transcript levels after a course of induction therapy was an independent prognostic factor for RFS (HR=0.263, 95%CI 0.081-0.851, P=0.026) and OS (HR=0.214, 95% CI 0.057-0.808, P=0.023) . During consolidation therapy and follow-up period, molecular relapse of 16 cases and hematologic relapse of 13 cases were identified by continuous dynamic monitoring of RUNX1-RUNX1T1 transcript levels, with a median interval of 4.0 (1.5-5.8) months from the molecular relapse to hematologic relapse. 2 cases of molecular relapse who received timely allogeneic hematopoietic stem cell transplantation did not experience hematologic relapse. Conclusion: Dynamic monitoring RUNX1-RUNX1T1 transcript levels by RQ-PCR technique can subdivide patients into relatively low and high risk group, early screen patients at high risk of relapse and provide a

  4. MRCP diagnosis of Mirizzi syndrome in a paediatric patient: importance of T1-weighted gradient echo images for diagnosis

    Energy Technology Data Exchange (ETDEWEB)

    Kaya, Diana; Karcaaltincaba, Musturay; Akhan, Okan; Haliloglu, Mithat [Hacettepe University School of Medicine, Department of Radiology, Sihhiye, Ankara (Turkey); Uslu, Nuray [Hacettepe University School of Medicine, Department of Pediatric Gastroenterology, Sihhiye, Ankara (Turkey)

    2006-09-15

    We report a 15-year-old boy with Mirizzi syndrome diagnosed by MR cholangiopancreatography (MRCP). Respiratory-triggered 3D MRCP was performed during free breathing. An impacted gallstone was noted in the infundibulum; this was not visible on T2-weighted images, but was hyperintense on T1-weighted gradient-echo images. This case illustrates the utility of 3D MRCP with parallel imaging in paediatric patients and the importance of T1-weighted gradient-echo images for the diagnosis of impacted gallstones. (orig.)

  5. Karyotyping of Brassica napus L. Based on C0t-1 DNA Banding by Fluorescence In Situ Hybridization

    Institute of Scientific and Technical Information of China (English)

    Wen-Hui WEI; Wan-Peng ZHAO; Li-Jun WANG; Bo CHEN; Yun-Chang LI; Yun-Chun SONG

    2005-01-01

    In order to precisely recognize and karyotype Brassica napus L. chromosomes, C0t- 1 DNA was extracted from its genomic DNA, labeled with biotin- 11-dUTP and in situ hybridized. The hybridized locations were detected by Cy3-conjugated streptavidin. Specific fluorescence in situ hybridization (FISH)signal bands were detected on all individual chromosome pairs. Each chromosome pair showed specific banding patterns. The B. napus karyotype has been constructed, for the first time, on the basis of both C0t-1 DNA FISH banding patterns and chromosome morphology.

  6. Europium-engineered iron oxide nanocubes with high T1 and T2 contrast abilities for MRI in living subjects

    Science.gov (United States)

    Yang, Lijiao; Zhou, Zijian; Liu, Hanyu; Wu, Changqiang; Zhang, Hui; Huang, Guoming; Ai, Hua; Gao, Jinhao

    2015-04-01

    Magnetic resonance imaging (MRI) contrast agents with both positive (T1) and negative (T2) contrast abilities are needed in clinical diagnosis for fault-free accurate detection of lesions. We report a facile synthesis of europium-engineered iron oxide (EuIO) nanocubes as T1 and T2 contrast agents for MRI in living subjects. The Eu(iii) oxide-embedded iron oxide nanoparticles significantly increase the T1 relaxivity with an enhanced positive contrast effect. EuIO nanocubes with 14 nm in diameter showed a high r1 value of 36.8 mM-1 s-1 with respect to total metal ions (Fe + Eu), which is about 3 times higher than that of Fe3O4 nanoparticles with similar size. Moreover, both r1 and r2 values of EuIO nanocubes can be tuned by varying their sizes and Eu doping ratios. After citrate coating, EuIO nanocubes can provide enhanced T1 and T2 contrast effects in small animals, particularly in the cardiac and liver regions. This work may provide an insightful strategy to design MRI contrast agents with both positive and negative contrast abilities for biomedical applications.Magnetic resonance imaging (MRI) contrast agents with both positive (T1) and negative (T2) contrast abilities are needed in clinical diagnosis for fault-free accurate detection of lesions. We report a facile synthesis of europium-engineered iron oxide (EuIO) nanocubes as T1 and T2 contrast agents for MRI in living subjects. The Eu(iii) oxide-embedded iron oxide nanoparticles significantly increase the T1 relaxivity with an enhanced positive contrast effect. EuIO nanocubes with 14 nm in diameter showed a high r1 value of 36.8 mM-1 s-1 with respect to total metal ions (Fe + Eu), which is about 3 times higher than that of Fe3O4 nanoparticles with similar size. Moreover, both r1 and r2 values of EuIO nanocubes can be tuned by varying their sizes and Eu doping ratios. After citrate coating, EuIO nanocubes can provide enhanced T1 and T2 contrast effects in small animals, particularly in the cardiac and liver

  7. Chaos in classical string dynamics in $\\hat{\\gamma}$ deformed $AdS_5 \\times T^{1,1}$

    CERN Document Server

    Panigrahi, Kamal L

    2016-01-01

    We consider a circular string in $\\hat{\\gamma}$ deformed $AdS_5 \\times T^{1,1}$ which is localized in the center of $AdS_5$ and winds around the two circles of deformed $T^{1,1}$. We observe chaos in the phase space of the circular string implying non-integrability of string dynamics. The chaotic behaviour in phase space is controlled by energy as well as the deforming parameter $\\hat{\\gamma}$. We further show that the point like object exhibits non-chaotic behaviour. Finally we calculate the Lyapunov exponent for both extended and point like object in support of our first result.

  8. ACCURACY OF MEASUREMENT OF NATURAL GAMMA RAY SPECTRA BY HD—8004 NaI(T1) GAMMA SPECTROMETER

    Institute of Scientific and Technical Information of China (English)

    朱国钦; 郑仁淑

    1995-01-01

    The measurement principle and analysis method of natural gammaray spectra using NaI(T1) scintillation spectrometer are briefly described first,then block diagrams of the HD-8004 NaI(T1) gamma-ray spectrometer,Finally,sample measurements are listed and discussed.The results are quite promising.Based on the analysis of these measurements,measures to improve the accuracy of spectrum measurement are proposed.It is well hoped that these measures can contribute to the development and application of gamma-ray spectrum measurement.

  9. Quantitative assessment of hepatic function: modified look-locker inversion recovery (MOLLI) sequence for T1 mapping on Gd-EOB-DTPA-enhanced liver MR imaging

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Jeong Hee [Seoul National University Hospital, Department of Radiology, Seoul (Korea, Republic of); Lee, Jeong Min; Han, Joon Koo; Choi, Byung Ihn [Seoul National University Hospital, Department of Radiology, Seoul (Korea, Republic of); Seoul National University College of Medicine, Institute of Radiation Medicine, Jongno-gu, Seoul (Korea, Republic of); Paek, Munyoung [Siemens Healthcare, Seoul (Korea, Republic of)

    2016-06-15

    To determine whether multislice T1 mapping of the liver using a modified look-locker inversion recovery (MOLLI) sequence on gadoxetic acid-enhanced magnetic resonance imaging (MRI) can be used as a quantitative tool to estimate liver function and predict the presence of oesophageal or gastric varices. Phantoms filled with gadoxetic acid were scanned three times using MOLLI sequence to test repeatability. Patients with chronic liver disease or liver cirrhosis who underwent gadoxetic acid-enhanced liver MRI including MOLLI sequence at 3 T were included (n = 343). Pre- and postcontrast T1 relaxation times of the liver (T1liver), changes between pre- and postcontrast T1liver (ΔT1liver), and adjusted postcontrast T1liver (postcontrast T1liver-T1spleen/T1spleen) were compared among Child-Pugh classes. In 62 patients who underwent endoscopy, all T1 parameters and spleen sizes were correlated with varices. Phantom study showed excellent repeatability of MOLLI sequence. As Child-Pugh scores increased, pre- and postcontrast T1liver were significantly prolonged (P < 0.001), and ΔT1liver and adjusted postcontrast T1liver decreased (P< 0.001). Adjusted postcontrast T1liver and spleen size were independently associated with varices (R{sup 2} = 0.29, P < 0.001). T1 mapping of the liver using MOLLI sequence on gadoxetic acid-enhanced MRI demonstrated potential in quantitatively estimating liver function, and adjusted postcontrast T1liver was significantly associated with varices. (orig.)

  10. CTX Correlation to Disease Duration and Adiponectin in Egyptian Children with T1DM/ Korelacija između CTX-a i trajanja bolesti i adiponektina kod egipatske dece sa T1DM

    Directory of Open Access Journals (Sweden)

    Hashim Amel A.

    2016-01-01

    Full Text Available Uvod: U ovoj studiji istraživali smo odnos između adiponektina i markera koštanih promena kod egipatske dece i ado­lescenata sa T1DM, uticaj trajanja bolesti na ove markere, kao i potencijalne korelacije između adiponektina i ko­štanih markera kod ovih pacijenata.

  11. T1~3期胃癌术中前哨淋巴结活检的意义%The clinical significance of sentinel lymph node biopsy in T1~3 gastric cancer

    Institute of Scientific and Technical Information of China (English)

    黄建豪; 吴智勇; 王少洪; 张仕义

    2013-01-01

    Objective To investigate the successful detection rate and accurate rate of sentinel nodes ( SLN ) in T1-3 gastric cancer. Methods Intraoperative lymphatic mapping and SLN biopsy ( SLNB ) with methylene blue were performed in 98 patients with T1-3 gastic cancer, who received subsequent standard radical gastrectomy with lymphadenecto-my ( D2 or D3 ). The successful detection rate and accurate rate of SLN were assessed. Results According to pathological diagnosis, T1 , T2 and T3 gastric cancer were revealed in 16, 46 and 36 cases, respectively. Stained nodes were detected in 90 cases ( success rate: 91.8% ). Thirty - nine cases were found with lymph node metastasis; among whom metastasis in both SLN and non - SLN, SLN alone or non - SLN alone were revealed in 18 , 12 and 9 cases, respectively. The successful detection rates were 96. 8% in T1-2 group and 83. 3% in T3 group, with accurate rates of 98. 3% and 73. 3% , respectively. Conclusion SLNB accurately predicts the lymph node metastatic status in T1-2 gastric cancer patients, routine lymph node dissection can avoid unnecessary D2 surgery in negative sentinel lymph node metastasis. In T3 group, SLNB can find abnormal lymph flow, providing intraoperative lymph node navigation.%目的 观测T1~3期胃癌术中前哨淋巴结(SLN)的检出率及准确率,探讨其临床意义.方法 在98例T1~3期胃癌根治术中,使用亚甲蓝进行染色,切取SLN,随后进行D2或D3手术.观测各T分期胃癌前哨淋巴结活检(SLNB)的检出率及准确率.结果 98例胃癌标本术后病理诊断为T1、T2、T3期分别为16、46及36 例.术中SLN成功显影90例,检出率为91.8 %.全组39例有淋巴结癌转移,其中SLN与非前哨淋巴结(non-SLN)均有转移者18例,仅SLN有转移者12例,仅non-SLN有转移者9例.T1~2期的检出率为96.8%,准确率为98.3%;T3期检出率为83.3%,准确率仅为73.3%.结论 SLNB可以准确预测T1~2期胃癌淋巴结转移状态,SLN阴性,有望免除常规D2

  12. File list: Pol.EmF.20.AllAg.C3HSLASH10T1SLASH2 [Chip-atlas[Archive

    Lifescience Database Archive (English)

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  18. File list: Pol.EmF.10.AllAg.C3HSLASH10T1SLASH2 [Chip-atlas[Archive

    Lifescience Database Archive (English)

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  20. File list: Unc.EmF.50.AllAg.C3HSLASH10T1SLASH2 [Chip-atlas[Archive

    Lifescience Database Archive (English)

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  2. File list: NoD.EmF.10.AllAg.C3HSLASH10T1SLASH2 [Chip-atlas[Archive

    Lifescience Database Archive (English)

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  3. File list: DNS.EmF.20.AllAg.C3HSLASH10T1SLASH2 [Chip-atlas[Archive

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  4. File list: Unc.EmF.05.AllAg.C3HSLASH10T1SLASH2 [Chip-atlas[Archive

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  5. File list: DNS.EmF.10.AllAg.C3HSLASH10T1SLASH2 [Chip-atlas[Archive

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  6. A 0.8-2.4 μm Transmission spectrum of the hot Jupiter CoRoT-1b

    Energy Technology Data Exchange (ETDEWEB)

    Schlawin, E.; Herter, T. [Astronomy Department, Cornell University, Ithaca, NY 14853 (United States); Zhao, M. [Department of Astronomy, Pennsylvania State University, University Park, PA 16802 (United States); Teske, J. K. [Astronomy Department, The University of Arizona, Tucson, AZ 85721 (United States)

    2014-03-01

    Hot Jupiters with brightness temperatures ≳2000 K can have TiO and VO molecules as gaseous species in their atmospheres. The TiO and VO molecules can potentially induce temperature inversions in hot Jupiter atmospheres and also have an observable signature of large optical to infrared transit depth ratios. Previous transmission spectra of very hot Jupiters have shown a lack of TiO and VO, but only in planets that also appear to lack temperature inversions. We measure the transmission spectrum of CoRoT-1b, a hot Jupiter that was predicted to have a temperature inversion potentially due to significant TiO and VO in its atmosphere. We employ the multi-object spectroscopy method using the SpeX and MORIS instruments on the Infrared Telescope Facility (IRTF) and the Gaussian process method to model red noise. By using a simultaneous reference star on the slit for calibration and a wide slit to minimize slit losses, we achieve transit depth precision of 0.03%-0.09%, comparable to the atmospheric scale height but detect no statistically significant molecular features. We combine our IRTF data with optical CoRoT transmission measurements to search for differences in the optical and near-infrared absorption that would arise from TiO/VO. Our IRTF spectrum and the CoRoT photometry disfavor a TiO/VO-rich spectrum for CoRoT-1b, suggesting that the atmosphere has another absorber that could create a temperature inversion or that the blackbody-like emission from the planet is due to a spectroscopically flat cloud, dust, or haze layer that smoothes out molecular features in both CoRoT-1b's emission and transmission spectra. This system represents the faintest planet hosting star (K = 12.2) with a measured planetary transmission spectrum.

  7. Repair of Staphylococcus aureus-infected wound with gene-modified C3H10T1/2 cells expressing BPI-BD3 fusion antibiotic peptide

    Directory of Open Access Journals (Sweden)

    Xin-ran ZHANG

    2015-10-01

    Full Text Available Objective To study the antibacterial and tissue reparative effect of BPI-BD3 gene-modified mesenchymal stem cells in a mouse model of wound infection. Methods C3H10T1/2 cells were transfected with recombinant adenovirus vector pAdxsi-BPI-BD3, the expression of BPI-BD3 fusion protein was verified by RT-PCR and Western blotting. Excision wound with a diameter of 1cm was inoculated with Staphylococcus aureuswas made on the back of 30 mice. The mice were randomly divided into 3 groups (10 each. Mice in group T were injected with BPI-BD3 gene-modified C3H10T1/2 cells through caudal vein, those in group C were injected with unmodified C3H10T1/2 cells, and in group N were injected with PBS as control. The wound repair result was evaluated by estimation of the percentage of remaining wound area and the amount of wound bacteria under the scar, followed by observation of pathological changes. Inflammatory reactions of the wounds were assessed accordingly. Results The amount of bacteria under the scar was less in group T than in the other two groups (P<0.05. It was also found that the wound healing process was faster in group T than in group C and group N. Pathological observation showed that the inflammatory reaction in group T was also significantly milder than in the other two groups. Conclusion BPI-BD3 gene-modified mesenchymal stem cells may enhance wound repair by controlling infection and promoting tissue regeneration, thus it may be promising in clinical application. DOI: 10.11855/j.issn.0577-7402.2015.09.07

  8. Photodissociation of acetone from 266 to 312 nm: Dynamics of CH3 + CH3CO channels on the S0 and T1 states

    Science.gov (United States)

    Lee, Kin Long Kelvin; Nauta, Klaas; Kable, Scott H.

    2017-01-01

    The photodissociation dynamics of acetone (CH3)2CO, cooled in a molecular beam, have been explored over the wavelength range 266-312 nm. Nascent CH3 fragments were detected by resonance-enhanced multiphoton ionization, followed by mass-selected ion imaging. For photolysis at λ = 306 nm, the image shows a sharp ring, which, when converted to a translational energy distribution, reveals a narrow Gaussian peak with a maximum at 90% of the available energy. As the photolysis energy is increased, the distribution slowly broadens and shifts to higher recoil translational energy. The fraction of available energy in translation energy decreases in favour of internal energy of the CH3CO fragment. These observations are consistent with a dynamical model in which the energy of the exit channel barrier on the T1 surface evolves mostly into relative translational energy. Energy in excess of the barrier is partitioned statistically into all degrees of freedom. No evidence was found for any other dynamical pathway producing CH3 fragments, including reaction on S0 or S1, for dissociation between 306 and 266 nm. For λ > 306 nm, a diffuse, slow recoil component to the image appears. The translational energy distribution for this component is fit well by a statistical prior distribution of energy. We attribute this component to dissociation on the S0, ground state surface; to our knowledge, this is the first direct observation of this channel. The appearance of S0 dynamics and the disappearance of the T1 component are consistent with previously inferred barrier height on T1 for the production of CH3CO + CH3. The possible atmospheric implications of our findings are discussed.

  9. Identification of T1D susceptibility genes within the MHC region by combining protein interaction networks and SNP genotyping data

    DEFF Research Database (Denmark)

    Brorsson, C.; Hansen, Niclas Tue; Hansen, Kasper Lage;

    2009-01-01

    region were analysed in 1000 affected offspring trios generated by the Type 1 Diabetes Genetics Consortium (T1DGC). The most associated SNP in each gene was chosen and genes were mapped to ppi networks for identification of interaction partners. The association testing and resulting interacting protein...

  10. Estimating kinetic parameters from dynamic contrast-enhanced T(1)-weighted MRI of a diffusable tracer: standardized quantities and symbols

    DEFF Research Database (Denmark)

    Tofts, P.S.; Brix, G; Buckley, D.L.

    1999-01-01

    We describe a standard set of quantity names and symbols related to the estimation of kinetic parameters from dynamic contrast-enhanced T(1)-weighted magnetic resonance imaging data, using diffusable agents such as gadopentetate dimeglumine (Gd-DTPA). These include a) the volume transfer constant K...

  11. Correlates of overweight and obesity in 5529 adolescents with type 1 diabetes: The T1D Exchange Clinic Registry.

    Science.gov (United States)

    Minges, Karl E; Whittemore, Robin; Weinzimer, Stuart A; Irwin, Melinda L; Redeker, Nancy S; Grey, Margaret

    2017-04-01

    To describe the prevalence of overweight and obesity in adolescents with type 1 diabetes (T1D) and to examine the associations among socio-demographic, clinical, and self-management factors by weight status. We analyzed baseline data obtained from 5529 adolescents with T1D (mean age=15.4±1.4years, 51.8% male, 77.9% white, mean HbA1c=8.7±1.8%; 72mmol/mol) from the T1D Exchange Clinic Registry. We examined correlates of weight status using multinomial logistic regression analyses. Overweight (22.9%) and obesity (13.1%) were prevalent in the overall sample and was highest among girls (40.8%) and adolescents of Hispanic/Latino race/ethnicity (46.1%). Female gender, older age, annual household income obesity. Adolescents who self-rated their health as fair/poor (vs. excellent) had the highest odds of obesity (OR 3.92, 95% CI 2.53-6.06). Overweight/obesity is prevalent among adolescents with T1D, especially among girls and those of diverse race/ethnicity. Some of these factors may be amenable to remediation and point to subgroups that can benefit from obesity prevention and management efforts. Copyright © 2017 Elsevier B.V. All rights reserved.

  12. Gut microbiota translocation to the pancreatic lymph nodes triggers NOD2 activation and contributes to T1D onset

    Science.gov (United States)

    Costa, Frederico R.C.; Françozo, Marcela C.S.; de Oliveira, Gabriela G.; Ignacio, Aline; Castoldi, Angela; Zamboni, Dario S.; Ramos, Simone G.; Câmara, Niels O.; de Zoete, Marcel R.; Palm, Noah W.; Flavell, Richard A.; Silva, João S.

    2016-01-01

    Type 1 diabetes (T1D) is an autoimmune disease that is triggered by both genetic and environmental factors, resulting in the destruction of pancreatic β cells. The disruption of the intestinal epithelial barrier and consequent escape of microbial products may be one of these environmental triggers. However, the immune receptors that are activated in this context remain elusive. We show here that during streptozotocin (STZ)-induced T1D, the nucleotide-binding oligomerization domain containing 2 (NOD2), but not NOD1, participates in the pathogenesis of the disease by inducing T helper 1 (Th1) and Th17 cells in the pancreatic LNs (PLNs) and pancreas. Additionally, STZ-injected wild-type (WT) diabetic mice displayed an altered gut microbiota compared with vehicle-injected WT mice, together with the translocation of bacteria to the PLNs. Interestingly, WT mice treated with broad-spectrum antibiotics (Abx) were fully protected from STZ-induced T1D, which correlated with the abrogation of bacterial translocation to the PLNs. Notably, when Abx-treated STZ-injected WT mice received the NOD2 ligand muramyl dipeptide, both hyperglycemia and the proinflammatory immune response were restored. Our results demonstrate that the recognition of bacterial products by NOD2 inside the PLNs contributes to T1D development, establishing a new putative target for intervention during the early stages of the disease. PMID:27325889

  13. Comparison of different pulse sequences for in vivo determination of T1 relaxation times in the human brain

    DEFF Research Database (Denmark)

    Kjaer, L; Henriksen, O

    1988-01-01

    (PSIR) sequence with TR varying between 0.24 and 8.0 s. The median T1 relaxation times obtained in cortical grey matter and cerebrospinal fluid were significantly shorter in the IR experiments at TR = 2 s than in those carried out at TR = 4 s. Concerning white matter the discrepancy was much less...

  14. Comparison of different pulse sequences for in vivo determination of T1 relaxation times in the human brain

    DEFF Research Database (Denmark)

    Kjaer, L; Henriksen, O

    1988-01-01

    ). T1 measurements were performed on the human brain using a whole body MR scanner operating at 1.5 tesla. Three different pulse sequences were compared including two 6-points inversion recovery (IR) sequences with TR = 2.0 s and 4.0, respectively, and a 12-points partial saturation inversion recovery...

  15. Prolonged bone marrow T1-relaxation in acute leukaemia. In vivo tissue characterization by magnetic resonance imaging

    DEFF Research Database (Denmark)

    Thomsen, C; Sørensen, P G; Karle, H

    1987-01-01

    osseous tissue. Nine patients with acute leukaemia, one patient with myelodysplastic syndrome, and ten normal volunteers were included in the study. The T1- and T2-relaxation processes were measured in the lumbar spine bone marrow using a wholebody superconductive MR-scanner operating at 1.5 Tesla...

  16. Alanylglutamine dipeptide and growth hormone maintain PepT1-mediated transport in oxidatively stressed Caco-2 cells.

    Science.gov (United States)

    Alteheld, B; Evans, M E; Gu, L H; Ganapathy, V; Leibach, F H; Jones, D P; Ziegler, T R

    2005-01-01

    Reactive oxygen species (ROS) produced by gut mucosal cells during conditions such as inflammatory bowel disease (IBD) may impair mucosal repair and nutrient transport/absorptive function. Absorption of di- and tripeptides in the small intestine and colon is mediated by the H(+)-dependent transporter PepT1, but effects of oxidative stress on di- and tripeptide transport are unknown. We assessed whether exposure to hydrogen peroxide (H(2)O(2)) influences dipeptide transport in human colonic epithelial (Caco-2) cells. Uptake of [(14)C]glycylsarcosine (Gly-Sar) was used to evaluate PepT1-mediated dipeptide transport. Exposure to 1-5 mmol/L H(2)O(2) for 24 h caused a dose-dependent decrease in Gly-Sar transport, which was associated with decreased PepT1 transport velocity (V(max)). Treatment with alanylglutamine (Ala-Gln) or growth hormone (GH) did not alter Caco-2 Gly-Sar transport in the absence of H(2)O(2). However, both Ala-Gln and GH prevented the decrease in dipeptide transport observed with 1 mmol/L H(2)O(2) treatment. Ala-Gln, but not GH, maintained cellular glutathione and prevented the decrease in PepT1 protein expression. Thus, these agents should be further investigated as potential therapies to improve absorption of small peptides in disorders associated with oxidative injury to the gut mucosa.

  17. 3-Amido-3-aryl-piperidines: A Novel Class of Potent, Selective, and Orally Active GlyT1 Inhibitors.

    Science.gov (United States)

    Pinard, Emmanuel; Alberati, Daniela; Alvarez-Sanchez, Ruben; Brom, Virginie; Burner, Serge; Fischer, Holger; Hauser, Nicole; Kolczewski, Sabine; Lengyel, Judith; Mory, Roland; Saladin, Christian; Schulz-Gasch, Tanja; Stalder, Henri

    2014-04-10

    3-Amido-3-aryl-piperidines were discovered as a novel structural class of GlyT1 inhibitors. The structure-activity relationship, which was developed, led to the identification of highly potent compounds exhibiting excellent selectivity against the GlyT2 isoform, drug-like properties, and in vivo activity after oral administration.

  18. Historische Technikakzeptanz – als kontextualisierende Technikzukunftsforschung am Fallbeispiel der T1-Duplexklasse der Pennsylvania Railroad, 1942–1951