WorldWideScience

Sample records for acoustic 4f imaging

  1. Acoustic fMRI noise : Linear time-invariant system model

    NARCIS (Netherlands)

    Sierra, Carlos V. Rizzo; Versluis, Maarten J.; Hoogduin, Johannes M.; Duifhuis, Hendrikus (Diek)

    Functional magnetic resonance imaging (fMRI) enables sites of brain activation to be localized in human subjects. For auditory system studies, however, the acoustic noise generated by the scanner tends to interfere with the assessments of this activation. Understanding and modeling fMRI acoustic

  2. Acoustical Imaging

    CERN Document Server

    Litniewski, Jerzy; Kujawska, Tamara; 31st International Symposium on Acoustical Imaging

    2012-01-01

    The International Symposium on Acoustical Imaging is a unique forum for advanced research, covering new technologies, developments, methods and theories in all areas of acoustics. This interdisciplinary Symposium has been taking place continuously since 1968. In the course of the years the proceedings volumes in the Acoustical Imaging Series have become a reference for cutting-edge research in the field. In 2011 the 31st International Symposium on Acoustical Imaging was held in Warsaw, Poland, April 10-13. Offering both a broad perspective on the state-of-the-art as well as  in-depth research contributions by the specialists in the field, this Volume 31 in the Series contains an excellent collection of papers in six major categories: Biological and Medical Imaging Physics and Mathematics of Acoustical Imaging Acoustic Microscopy Transducers and Arrays Nondestructive Evaluation and Industrial Applications Underwater Imaging

  3. 30th International Acoustical Imaging Symposium

    CERN Document Server

    Jones, Joie; Lee, Hua

    2011-01-01

    The International Symposium on Acoustical Imaging is a unique forum for advanced research, covering new technologies, developments, methods and theories in all areas of acoustics. This interdisciplinary Symposium has been taking place every two years since 1968. In the course of the years the proceedings volumes in the Acoustical Imaging Series have become a reference for cutting-edge research in the field. In 2009 the 30th International Symposium on Acoustical Imaging was held in Monterey, CA, USA, March 1-4. Offering both a broad perspective on the state-of-the-art as well as  in-depth research contributions by the specialists in the field, this Volume 30 in the Series contains an excellent collection of forty three papers presented in five major categories: Biomedical Imaging Acoustic Microscopy Non-Destructive Evaluation Systems Analysis Signal Analysis and Image Processing Audience Researchers in medical imaging and biomedical instrumentation experts.

  4. Acoustical Imaging

    CERN Document Server

    Akiyama, Iwaki

    2009-01-01

    The 29th International Symposium on Acoustical Imaging was held in Shonan Village, Kanagawa, Japan, April 15-18, 2007. This interdisciplinary Symposium has been taking place every two years since 1968 and forms a unique forum for advanced research, covering new technologies, developments, methods and theories in all areas of acoustics. In the course of the years the volumes in the Acoustical Imaging Series have developed and become well-known and appreciated reference works. Offering both a broad perspective on the state-of-the-art in the field as well as an in-depth look at its leading edge research, this Volume 29 in the Series contains again an excellent collection of seventy papers presented in nine major categories: Strain Imaging Biological and Medical Applications Acoustic Microscopy Non-Destructive Evaluation and Industrial Applications Components and Systems Geophysics and Underwater Imaging Physics and Mathematics Medical Image Analysis FDTD method and Other Numerical Simulations Audience Researcher...

  5. Acoustic noise in functional magnetic resonance imaging reduces pain unpleasantness ratings.

    Science.gov (United States)

    Boyle, Y; Bentley, D E; Watson, A; Jones, A K P

    2006-07-01

    Functional magnetic resonance imaging (fMRI) is increasingly used in cognitive studies. Unfortunately, the scanner produces acoustic noise during the image acquisition process. Interference from acoustic noise is known to affect auditory, visual and motor processing, raising the possibility that acoustic interference may also modulate processing of other sensory modalities such as pain. With the increasing use of fMRI in the investigation of the mechanisms of pain perception, particularly in relation to attention, this issue has become highly relevant. Pain is a complex experience, composed of sensory-discriminative, affective-motivational and cognitive-evaluative components. The aim of this experiment was to assess the effect of MRI scanner noise, compared to white noise, on the affective (unpleasantness) and the sensory-discriminative (localisation) components of pain. Painful radiant heat from a CO(2) laser was delivered to the skin of the right forearm in 24 healthy volunteers. The volunteers attended to either pain location or pain unpleasantness during three conditions: i) no noise, ii) exposure to MRI scanner noise (85 dB) or iii) exposure to white noise (85 dB). Both MRI scanner noise and white noise significantly reduced unpleasantness ratings (from 5.1 +/- 1.6 in the control condition to 4.7 +/- 1.5 (P = 0.002) and 4.6 +/- 1.6 (P white noise respectively), whereas the ability to localise pain was not significantly affected (from 85.4 +/- 9.2% correct in the control condition to 83.1 +/- 10.3% (P = 0.06) and 83.9 +/- 9.5% (P = 0.27) with MRI scanner and white noise respectively). This phenomenon should be taken into account in the design of fMRI studies into human pain perception.

  6. Optimization of a Biometric System Based on Acoustic Images

    Directory of Open Access Journals (Sweden)

    Alberto Izquierdo Fuente

    2014-01-01

    Full Text Available On the basis of an acoustic biometric system that captures 16 acoustic images of a person for 4 frequencies and 4 positions, a study was carried out to improve the performance of the system. On a first stage, an analysis to determine which images provide more information to the system was carried out showing that a set of 12 images allows the system to obtain results that are equivalent to using all of the 16 images. Finally, optimization techniques were used to obtain the set of weights associated with each acoustic image that maximizes the performance of the biometric system. These results improve significantly the performance of the preliminary system, while reducing the time of acquisition and computational burden, since the number of acoustic images was reduced.

  7. Optimization of a Biometric System Based on Acoustic Images

    Science.gov (United States)

    Izquierdo Fuente, Alberto; Del Val Puente, Lara; Villacorta Calvo, Juan J.; Raboso Mateos, Mariano

    2014-01-01

    On the basis of an acoustic biometric system that captures 16 acoustic images of a person for 4 frequencies and 4 positions, a study was carried out to improve the performance of the system. On a first stage, an analysis to determine which images provide more information to the system was carried out showing that a set of 12 images allows the system to obtain results that are equivalent to using all of the 16 images. Finally, optimization techniques were used to obtain the set of weights associated with each acoustic image that maximizes the performance of the biometric system. These results improve significantly the performance of the preliminary system, while reducing the time of acquisition and computational burden, since the number of acoustic images was reduced. PMID:24616643

  8. Acoustic-noise-optimized diffusion-weighted imaging.

    Science.gov (United States)

    Ott, Martin; Blaimer, Martin; Grodzki, David M; Breuer, Felix A; Roesch, Julie; Dörfler, Arnd; Heismann, Björn; Jakob, Peter M

    2015-12-01

    This work was aimed at reducing acoustic noise in diffusion-weighted MR imaging (DWI) that might reach acoustic noise levels of over 100 dB(A) in clinical practice. A diffusion-weighted readout-segmented echo-planar imaging (EPI) sequence was optimized for acoustic noise by utilizing small readout segment widths to obtain low gradient slew rates and amplitudes instead of faster k-space coverage. In addition, all other gradients were optimized for low slew rates. Volunteer and patient imaging experiments were conducted to demonstrate the feasibility of the method. Acoustic noise measurements were performed and analyzed for four different DWI measurement protocols at 1.5T and 3T. An acoustic noise reduction of up to 20 dB(A) was achieved, which corresponds to a fourfold reduction in acoustic perception. The image quality was preserved at the level of a standard single-shot (ss)-EPI sequence, with a 27-54% increase in scan time. The diffusion-weighted imaging technique proposed in this study allowed a substantial reduction in the level of acoustic noise compared to standard single-shot diffusion-weighted EPI. This is expected to afford considerably more patient comfort, but a larger study would be necessary to fully characterize the subjective changes in patient experience.

  9. Development of novel imaging probe for optical/acoustic radiation imaging (OARI).

    Science.gov (United States)

    Ejofodomi, O'tega A; Zderic, Vesna; Zara, Jason M

    2013-11-01

    Optical/acoustic radiation imaging (OARI) is a novel imaging modality being developed to interrogate the optical and mechanical properties of soft tissues. OARI uses acoustic radiation force to generate displacement in soft tissue. Optical images before and after the application of the force are used to generate displacement maps that provide information about the mechanical properties of the tissue under interrogation. Since the images are optical images, they also represent the optical properties of the tissue as well. In this paper, the authors present the first imaging probe that uses acoustic radiation force in conjunction with optical coherence tomography (OCT) to provide information about the optical and mechanical properties of tissues to assist in the diagnosis and staging of epithelial cancers, and in particular bladder cancer. The OARI prototype probe consisted of an OCT probe encased in a plastic sheath, a miniaturized transducer glued to a plastic holder, both of which were encased in a 10 cm stainless steel tube with an inner diameter of 10 mm. The transducer delivered an acoustic intensity of 18 W/cm(2) and the OCT probe had a spatial resolution of approximately 10-20 μm. The tube was filled with deionized water for acoustic coupling and covered by a low density polyethylene cap. The OARI probe was characterized and tested on bladder wall phantoms. The phantoms possessed Young's moduli ranging from 10.2 to 12 kPa, mass density of 1.05 g/cm(3), acoustic attenuation coefficient of 0.66 dB/cm MHz, speed of sound of 1591 m/s, and optical scattering coefficient of 1.80 mm(-1). Finite element model (FEM) theoretical simulations were performed to assess the performance of the OARI probe. The authors obtained displacements of 9.4, 8.7, and 3.4 μm for the 3%, 4%, and 5% bladder wall phantoms, respectively. This shows that the probe is capable of generating optical images, and also has the ability to generate and track displacements in tissue. This will

  10. Scanning electron-acoustic imaging of residual stress distributions in aluminum metal and ZrSiO4 multiphase ceramics

    International Nuclear Information System (INIS)

    Zhang, B.Y.; Jiang, F.M.; Shi, Y.; Yin, Q.R.; Qian, M.L.

    1997-01-01

    The scanning electron-acoustic imaging technique has been used in the characterization of the residual stress field distributions existing in the subsurface in aluminum disks and 20 vol% SiC ( w)/ZrSiO 4 multiphase ceramics left by Vicker close-quote s indentation. The experimental results reveal that the distribution areas are the plastic-elastic interchange zones. The electron-acoustic signal generation mechanism in the samples are discussed. copyright 1997 American Institute of Physics

  11. Laser-induced acoustic imaging of underground objects

    Science.gov (United States)

    Li, Wen; DiMarzio, Charles A.; McKnight, Stephen W.; Sauermann, Gerhard O.; Miller, Eric L.

    1999-02-01

    This paper introduces a new demining technique based on the photo-acoustic interaction, together with results from photo- acoustic experiments. We have buried different types of targets (metal, rubber and plastic) in different media (sand, soil and water) and imaged them by measuring reflection of acoustic waves generated by irradiation with a CO2 laser. Research has been focused on the signal acquisition and signal processing. A deconvolution method using Wiener filters is utilized in data processing. Using a uniform spatial distribution of laser pulses at the ground's surface, we obtained 3D images of buried objects. The images give us a clear representation of the shapes of the underground objects. The quality of the images depends on the mismatch of acoustic impedance of the buried objects, the bandwidth and center frequency of the acoustic sensors and the selection of filter functions.

  12. TU-F-CAMPUS-I-04: Head-Only Asymmetric Gradient System Evaluation: ACR Image Quality and Acoustic Noise

    Energy Technology Data Exchange (ETDEWEB)

    Weavers, P; Shu, Y; Tao, S; Bernstein, M [Mayo Clinic, Rochester, Minnesota (United States); Lee, S; Piel, J; Foo, T [GE Global Research, Niskayuna, NY (United States); Mathieu, J-B [GE Healthcare, Florence, SC (Italy)

    2015-06-15

    Purpose: A high-performance head-only magnetic resonance imaging gradient system with an acquisition volume of 26 cm employing an asymmetric design for the transverse coils has been developed. It is able to reach a magnitude of 85 mT/m at a slew rate of 700 T/m/s, but operated at 80 mT/m and 500 T/m/s for this test. A challenge resulting from this asymmetric design is that the gradient nonlinearly exhibits both odd- and even-ordered terms, and as the full imaging field of view is often used, the nonlinearity is pronounced. The purpose of this work is to show the system can produce clinically useful images after an on-site gradient nonlinearity calibration and correction, and show that acoustic noise levels fall within non-significant risk (NSR) limits for standard clinical pulse sequences. Methods: The head-only gradient system was inserted into a standard 3T wide-bore scanner without acoustic damping. The ACR phantom was scanned in an 8-channel receive-only head coil and the standard American College of Radiology (ACR) MRI quality control (QC) test was performed. Acoustic noise levels were measured for several standard pulse sequences. Results: Images acquired with the head-only gradient system passed all ACR MR image quality tests; Both even and odd-order gradient distortion correction terms were required for the asymmetric gradients to pass. Acoustic noise measurements were within FDA NSR guidelines of 99 dBA (with assumed 20 dBA hearing protection) A-weighted and 140 dB for peak for all but one sequence. Note the gradient system was installed without any shroud or acoustic batting. We expect final system integration to greatly reduce noise experienced by the patient. Conclusion: A high-performance head-only asymmetric gradient system operating at 80 mT/m and 500 T/m/s conforms to FDA acoustic noise limits in all but one case, and passes all the ACR MR image quality control tests. This work was supported in part by the NIH grant 5R01EB010065.

  13. TU-F-CAMPUS-I-04: Head-Only Asymmetric Gradient System Evaluation: ACR Image Quality and Acoustic Noise

    International Nuclear Information System (INIS)

    Weavers, P; Shu, Y; Tao, S; Bernstein, M; Lee, S; Piel, J; Foo, T; Mathieu, J-B

    2015-01-01

    Purpose: A high-performance head-only magnetic resonance imaging gradient system with an acquisition volume of 26 cm employing an asymmetric design for the transverse coils has been developed. It is able to reach a magnitude of 85 mT/m at a slew rate of 700 T/m/s, but operated at 80 mT/m and 500 T/m/s for this test. A challenge resulting from this asymmetric design is that the gradient nonlinearly exhibits both odd- and even-ordered terms, and as the full imaging field of view is often used, the nonlinearity is pronounced. The purpose of this work is to show the system can produce clinically useful images after an on-site gradient nonlinearity calibration and correction, and show that acoustic noise levels fall within non-significant risk (NSR) limits for standard clinical pulse sequences. Methods: The head-only gradient system was inserted into a standard 3T wide-bore scanner without acoustic damping. The ACR phantom was scanned in an 8-channel receive-only head coil and the standard American College of Radiology (ACR) MRI quality control (QC) test was performed. Acoustic noise levels were measured for several standard pulse sequences. Results: Images acquired with the head-only gradient system passed all ACR MR image quality tests; Both even and odd-order gradient distortion correction terms were required for the asymmetric gradients to pass. Acoustic noise measurements were within FDA NSR guidelines of 99 dBA (with assumed 20 dBA hearing protection) A-weighted and 140 dB for peak for all but one sequence. Note the gradient system was installed without any shroud or acoustic batting. We expect final system integration to greatly reduce noise experienced by the patient. Conclusion: A high-performance head-only asymmetric gradient system operating at 80 mT/m and 500 T/m/s conforms to FDA acoustic noise limits in all but one case, and passes all the ACR MR image quality control tests. This work was supported in part by the NIH grant 5R01EB010065

  14. Acoustic imaging system

    Science.gov (United States)

    Smith, Richard W.

    1979-01-01

    An acoustic imaging system for displaying an object viewed by a moving array of transducers as the array is pivoted about a fixed point within a given plane. A plurality of transducers are fixedly positioned and equally spaced within a laterally extending array and operatively directed to transmit and receive acoustic signals along substantially parallel transmission paths. The transducers are sequentially activated along the array to transmit and receive acoustic signals according to a preestablished sequence. Means are provided for generating output voltages for each reception of an acoustic signal, corresponding to the coordinate position of the object viewed as the array is pivoted. Receptions from each of the transducers are presented on the same display at coordinates corresponding to the actual position of the object viewed to form a plane view of the object scanned.

  15. Noninvasive imaging of tumor integrin expression using 18F-labeled RGD dimer peptide with PEG4 linkers

    International Nuclear Information System (INIS)

    Liu, Zhaofei; Liu, Shuanglong; Wang, Fan; Liu, Shuang; Chen, Xiaoyuan

    2009-01-01

    Various radiolabeled Arg-Gly-Asp (RGD) peptides have been previously investigated for tumor integrin α v β 3 imaging. To further develop RGD radiotracers with enhanced tumor-targeting efficacy and improved in vivo pharmacokinetics, we designed a new RGD homodimeric peptide with two PEG 4 spacers (PEG 4 = 15-amino-4,7,10,13-tetraoxapentadecanoic acid) between the two monomeric RGD motifs and one PEG 4 linker on the glutamate α-amino group ( 18 F-labeled PEG 4 -E[PEG 4 -c(RGDfK)] 2 , P-PRGD2), as a promising agent for noninvasive imaging of integrin expression in mouse models. P-PRGD2 was labeled with 18 F via 4-nitrophenyl 2- 18 F-fluoropropionate ( 18 F-FP) prosthetic group. In vitro and in vivo characteristics of the new dimeric RGD peptide tracer 18 F-FP-P-PRGD2 were investigated and compared with those of 18 F-FP-P-RGD2 ( 18 F-labeled RGD dimer without two PEG 4 spacers between the two RGD motifs). The ability of 18 F-FP-P-PRGD2 to image tumor vascular integrin expression was evaluated in a 4T1 murine breast tumor model. With the insertion of two PEG 4 spacers between the two RGD motifs, 18 F-FP-P-PRGD2 showed enhanced integrin α v β 3 -binding affinity, increased tumor uptake and tumor-to-nontumor background ratios compared with 18 F-FP-P-RGD2 in U87MG tumors. MicroPET imaging with 18 F-FP-P-PRGD2 revealed high tumor contrast and low background in tumor-bearing nude mice. Biodistribution studies confirmed the in vivo integrin α v β 3 -binding specificity of 18 F-FP-P-RGD2. 18 F-FP-P-PRGD2 can specifically image integrin α v β 3 on the activated endothelial cells of tumor neovasculature. 18 F-FP-P-PRGD2 can provide important information on integrin expression on the tumor vasculature. The high integrin binding affinity and specificity, excellent pharmacokinetic properties and metabolic stability make the new RGD dimeric tracer 18 F-FP-P-PRGD2 a promising agent for PET imaging of tumor angiogenesis and for monitoring the efficacy of antiangiogenic

  16. MR imaging of acoustic neurinoma

    International Nuclear Information System (INIS)

    Miyamachi, Keikichi; Aida, Toshimitsu; Abe, Hiroshi; Nomura, Mikio; Saitou, Hisatoshi.

    1988-01-01

    Fifteen cases of acoustic neurinomas were studied by the use of a 0.15 T magnetic resonance (MR) imager. Three of the patients were male, and twelve were female. The patients' ages ranged from 23 to 67 years. The tumors were measured by means of MR images; the maximum was 37.5 mm across, and the minimum, 10 mm. The MR images of the acoustic neurinomas were hypointense on the T 1 -weighted images except in one case (isointense), while all cases were hyperintense on the T 2 -weighted images. MRI was much better than contrastenhanced CT for internal auditory canal (IAC) tumors (78 % versus 36 %), especially by means of coronal oblique image on T 2 -weighted images. In addition, MRI was more useful in demonstrating a VII - VIII neurocomplex on the non-affected side than was CT (57 % versus 10 %), but it did not demonstrate a VII - VIII neurocomplex on the affected side when a 0.15 T MR imager was used. It is very effective to separate the tumor from the tentorium cerebelli when it is necessary to differentiate an acoustic neurinoma from a meningioma at the cerebellopontine angle. A coronal or coronal oblique image offers information for use in separating the tentorium cerebelli. In small IAC tumors, the increased protein content of the cerebro-spinal fluid in an obstructed IAC and the bound-water effect in small collections of fluid may shorten the relaxation times of the trapped intracanalicular fluid, producing difficulty in the ability to diagnosis small tumors. To reveal cystic components, it was found to be effective to use Gd-DTPA or short-TR short-TE spin-echo images. (author)

  17. Comparison of acoustic radiation force impulse imaging (ARFI) to liver biopsy histologic scores in the evaluation of chronic liver disease: A pilot study.

    Science.gov (United States)

    Haque, Mazhar; Robinson, Charlotte; Owen, David; Yoshida, Eric M; Harris, Alison

    2010-01-01

    Acoustic Radiation Force Impulse Imaging (ARFI) is a novel non invasive technique studying the localized mechanical properties of tissue by utilising short, high intensity acoustic pulses (shear wave pulses) to assess the mechanical response (tissue displacement), providing a measure of tissue elasticity. The aim of this study is to investigate the feasibility of ARFI imaging as a non-invasive method for the assessment of liver fibrosis compared to liver biopsy scores. A prospective blind comparison study of ARFI elastography (Virtual Touch Imaging., ACUSON S2000 Ultrasound Unit, Siemens, Mountain View CA) in a consecutive series of patients who underwent liver biopsy for assessment of fibrosis in chronic liver disease. ARFI shear-wave propagation velocity was measured in meters per second. Mean ARFI velocities were compared with both Batts-Ludwig (F0 to F4) and Modified Ishak scores (F0 to F4) for fibrosis in liver biopsy findings. Twenty-one patients with chronic liver disease (Hepatitis C (HCV) =16, Hepatitis B (HBV) = 1, both HCV and HBV = 1 Alcoholic liver disease (ALD) = 1, others = 2) underwent ARFI and liver biopsy on the same day. The Spearman correlation coefficients between the median values of the ARFI measurements and the histological fibrosis stage of the Modified Ishak score and Batts-Lud- (3) wig score were both highly significant (p shak score in chronic liver disease. It.s accuracy in prediction of severe fibrosis and cirrhosis is maximal in comparison with earlier stages.

  18. Subwavelength image manipulation through oblique and herringbone layered acoustic systems

    International Nuclear Information System (INIS)

    Li, Chunhui; Jia, Han; Ke, Manzhu; Li, Yixiang; Liu, Zhengyou

    2014-01-01

    In this paper, an oblique and a herringbone layered acoustic structure are experimentally and theoretically demonstrated to manipulate acoustic subwavelength images. An imaging resolution of less than one tenth of a wavelength is achieved with both optimized systems, and lateral image shift has been realized by an oblique layered system. The thicknesses of both the oblique and the herringbone layered acoustic systems are largely reduced through utilizing the oblique or herringbone wave propagation path instead of the vertical wave propagation path in the rectangular layered planar acoustic system. With smaller size and subwavelength image manipulation, the acoustic systems are more favourable for practical application. (paper)

  19. Efficacy of passive acoustic screening: implications for the design of imager and MR-suite.

    Science.gov (United States)

    Moelker, Adriaan; Vogel, Mika W; Pattynama, Peter M T

    2003-02-01

    To investigate the efficacy of passive acoustic screening in the magnetic resonance (MR) environment by reducing direct and indirect MR-related acoustic noise, both from the patient's and health worker's perspective. Direct acoustic noise refers to sound originating from the inner and outer shrouds of the MR imager, and indirect noise to acoustic reflections from the walls of the MR suite. Sound measurements were obtained inside the magnet bore (patient position) and at the entrance of the MR imager (health worker position). Inner and outer shrouds and walls were lined with thick layers of sound insulation to eliminate the direct and indirect acoustic pathways. Sound pressure levels (SPLs) and octave band frequencies were acquired during various MR imaging sequences at 1.5 T. Inside the magnet bore, direct acoustic noise radiating from the inner shroud was most relevant, with substantial reductions of up to 18.8 dB when using passive screening of the magnetic bore. At the magnet bore entrance, blocking acoustic noise from the outer shroud and reflections showed significant reductions of 4.5 and 2.8 dB, respectively, and 9.4 dB when simultaneously applied. Inner shroud coverage contributed minimally to the overall SPL reduction. Maximum noise reduction by passive acoustic screening can be achieved by reducing direct sound conduction through the inner and outer shrouds. Additional measures to optimize the acoustic properties of the MR suite have only little effect. Copyright 2003 Wiley-Liss, Inc.

  20. Assessing hepatic fibrosis: comparing the intravoxel incoherent motion in MRI with acoustic radiation force impulse imaging in US

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Chih-Horng; Liang, Po-Chin; Shih, Tiffany Ting-Fang [National Taiwan University Hospital, Department of Medical Imaging, Taipei (China); National Taiwan University College of Medicine, Department of Radiology, Taipei (China); Ho, Ming-Chih; Hu, Rey-Heng; Lai, Hong-Shiee [National Taiwan University Hospital and College of Medicine, Department of Surgery, Taipei (China); Jeng, Yung-Ming [National Taiwan University Hospital and College of Medicine, Department of Pathology, Taipei (China)

    2015-12-15

    This study compared the diagnostic performance of intravoxel incoherent motion (IVIM) in magnetic resonance imaging (MRI) and acoustic radiation force impulse imaging (ARFI) in ultrasound (US) for liver fibrosis (LF) evaluation. A total of 49 patients scheduled for liver surgery were recruited. LF in the non-tumorous liver parenchyma at the right lobe was estimated using a slow diffusion coefficient, fast diffusion coefficient (D{sub fast}), perfusion fraction (f) of the IVIM parameters, the total apparent diffusion coefficient of conventional diffusion-weighted imaging and the shear wave velocity (Vs) of ARFI. LF was graded using the Metavir scoring system on histological examination. The Spearman rank correlation coefficient for correlation and analysis of variance was used for determining difference. The diagnostic performance was compared using receiver operating characteristic curve analysis. LF exhibited significant correlation with the three parameters D{sub fast}, f, and Vs (r = -0.528, -0.337, and 0.481, respectively, P < 0.05). The D{sub fast} values in the F4 group were significantly lower than those in the F0, F1 and F2 groups. D{sub fast} exhibited a non-inferior performance for diagnosing all fibrosis grades compared with that of Vs. Both IVIM and ARFI provide reliable estimations for the noninvasive assessment of LF. (orig.)

  1. Synthetic Aperture Acoustic Imaging for Roadside Detection of Solid Objects

    Science.gov (United States)

    2014-11-20

    Testing I I I I Cinderblock Foam block Isometric and translucent view of the weighted foam block . .-.-; Weighted foam block Figure 2.3... concrete block (CB, Fig. 2.4). Conven- tional methods for identifying targets in a radar or acoustic imaging system (also known as Automatic Target...and curb, or than the grass-covered hill beyond the sidewalk. However, there is a strong acoustic return from a seam in the sidewalk concrete that runs

  2. Transmission mode acoustic time-reversal imaging for nondestructive evaluation

    Science.gov (United States)

    Lehman, Sean K.; Devaney, Anthony J.

    2002-11-01

    In previous ASA meetings and JASA papers, the extended and formalized theory of transmission mode time reversal in which the transceivers are noncoincident was presented. When combined with the subspace concepts of a generalized MUltiple SIgnal Classification (MUSIC) algorithm, this theory is used to form super-resolution images of scatterers buried in a medium. These techniques are now applied to ultrasonic nondestructive evaluation (NDE) of parts, and shallow subsurface seismic imaging. Results are presented of NDE experiments on metal and epoxy blocks using data collected from an adaptive ultrasonic array, that is, a ''time-reversal machine,'' at Lawrence Livermore National Laboratory. Also presented are the results of seismo-acoustic subsurface probing of buried hazardous waste pits at the Idaho National Engineering and Environmental Laboratory. [Work performed under the auspices of the U.S. Department of Energy by University of California Lawrence Livermore National Laboratory under Contract No. W-7405-Eng-48.] [Work supported in part by CenSSIS, the Center for Subsurface Sensing and Imaging Systems, under the Engineering Research Centers Program of the NSF (award number EEC-9986821) as well as from Air Force Contracts No. F41624-99-D6002 and No. F49620-99-C0013.

  3. Homotopy Based Reconstruction from Acoustic Images

    DEFF Research Database (Denmark)

    Sharma, Ojaswa

    of the inherent arrangement. The problem of reconstruction from arbitrary cross sections is a generic problem and is also shown to be solved here using the mathematical tool of continuous deformations. As part of a complete processing, segmentation using level set methods is explored for acoustic images and fast...... GPU (Graphics Processing Unit) based methods are suggested for a streaming computation on large volumes of data. Validation of results for acoustic images is not straightforward due to unavailability of ground truth. Accuracy figures for the suggested methods are provided using phantom object...

  4. PET imaging of the brain serotonin transporters (SERT) with N,N-dimethyl-2-(2-amino-4-[18F]fluorophenylthio)benzylamine (4-[18F]-ADAM) in humans: a preliminary study

    International Nuclear Information System (INIS)

    Huang, Wen-Sheng; Huang, San-Yuan; Ho, Pei-Shen; Yeh, Chin-Bin; Ma, Kuo-Hsing; Huang, Ya-Yao; Shiue, Chyng-Yann; Liu, Ren-Syuan; Cheng, Cheng-Yi

    2013-01-01

    The aim of this study was to assess the feasibility of using 4-[ 18 F]-ADAM as a brain SERT imaging agent in humans. Enrolled in the study were 19 healthy Taiwanese subjects (11 men, 8 women; age 33 ± 9 years). The PET data were semiquantitatively analyzed and expressed as specific uptake ratios (SUR) and distribution volume ratios (DVR) using the software package PMOD. The SUR and DVR of 4-[ 18 F]-ADAM in the raphe nucleus (RN), midbrain (MB), thalamus (TH), striatum (STR) and prefrontal cortex (PFC) were determined using the cerebellum (CB) as the reference region. 4-[ 18 F]-ADAM bound to known SERT-rich regions in human brain. The order of the regional brain uptake was MB (RN) > TH > STR > PFC > CB. The DVR (n = 4, t* = 60 min) in the RN, TH, STR and PFC were 3.00 ± 0.50, 2.25 ± 0.45, 2.05 ± 0.31 and 1.40 ± 0.13, respectively. The optimal time for imaging brain SERT with 4-[ 18 F]-ADAM was 120-140 min after injection. At the optimal imaging time, the SURs (n = 15) in the MB, TH, STR, and PFC were 2.25 ± 0.20, 2.28 ± 0.20, 2.12 ± 0.18 and 1.47 ± 0.14, respectively. There were no significant differences in SERT availability between men and women (p 18 F]-ADAM was safe for human studies and its distribution in human brain appeared to correlate well with the known distribution of SERT in the human brain. In addition, it had high specific binding and a reasonable optimal time for imaging brain SERT in humans. Thus, 4-[ 18 F]-ADAM may be feasible for assessing the status of brain SERT in humans. (orig.)

  5. Vibro-acoustic Imaging at the Breazeale Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Smith, James Arthur [Idaho National Lab. (INL), Idaho Falls, ID (United States); Jewell, James Keith [Idaho National Lab. (INL), Idaho Falls, ID (United States); Lee, James Edwin [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2016-09-01

    The INL is developing Vibro-acoustic imaging technology to characterize microstructure in fuels and materials in spent fuel pools and within reactor vessels. A vibro-acoustic development laboratory has been established at the INL. The progress in developing the vibro-acoustic technology at the INL is the focus of this report. A successful technology demonstration was performed in a working TRIGA research reactor. Vibro-acoustic imaging was performed in the reactor pool of the Breazeale reactor in late September of 2015. A confocal transducer driven at a nominal 3 MHz was used to collect the 60 kHz differential beat frequency induced in a spent TRIGA fuel rod and empty gamma tube located in the main reactor water pool. Data was collected and analyzed with the INLDAS data acquisition software using a short time Fourier transform.

  6. PET imaging of cerebral metabolic change in tinnitus using 18F-FDG

    International Nuclear Information System (INIS)

    Tian Jiahe; Wang Hongtian; Yin Dayi; Yao Shulin; Shao Mingzhe; Yang Weiyan; Jiang Sichang

    2000-01-01

    Tinnitus is an auditory disorder hardly assessable by clinical technology. PET imaging of the brain in 13 cases with and 10 without tinnitus was undertaken at 40 min after injection of 280-440 MBq 18 F-FDG. To ensure the quality of the PET study, all cases followed a normalized procedure with visual and auditory blockage. CT/MRI imaging and routine acoustic tests were carried out in all subjects. PET revealed that an increased uptake of 18 F-FDG at left med-temporal lobe (primary auditory center, PAC) present exclusively in tinnitus, regardless the side of hearing hallucination. Significant asymmetry was noted between left and right PAC, but not at other cortex area. While control cases showed no asymmetric uptake between two hemispheres. The abnormal PAC uptake did not respond to external pure sound stimulus, nor did it relate to the severity of hearing loss assessed by acoustic tests. No anatomical or morphological alteration could be proven on CT/MRI. In conclusion, PET/ 18 F-FDG objectively revealed an increased metabolic change at left PAC in tinnitus, which is of diagnostic value; and there is evidence suggesting tinnitus is most likely induced by a functional change in the brain

  7. Insulinoma imaging with glucagon-like peptide-1 receptor targeting probe (18)F-FBEM-Cys (39)-exendin-4.

    Science.gov (United States)

    Xu, Yuping; Pan, Donghui; Xu, Qing; Zhu, Chen; Wang, Lizhen; Chen, Fei; Yang, Runlin; Luo, Shineng; Yang, Min

    2014-09-01

    Glucagon-like peptide-1 receptor (GLP-1R) is a specific target for insulinomas imaging since it is overexpressed in the tumor. Exendin-4 exhibits high affinity for the GLP-1R. In this study, a novel (18)F-labeled exendin-4 analog, (18)F-FBEM-Cys(39)-exendin-4, was synthesized and its potentials for GLP-1R imaging were also evaluated. (18)F-FBEM was synthesized by coupling (18)F-fluorobenzoic acid ((18)F-FBA) with N-(2-aminoethyl) maleimide, and the reaction conditions were optimized. Cys(39)-exendin-4 was then conjugated with (18)F-FBEM to obtain (18)F-FBEM-Cys(39)-exendin-4. The GLP-1R targeting potential and pharmacokinetic profile of the tracer were analyzed in INS-1 insulinoma and MDA-MB-435 breast tumor model, respectively. Under the optimal conditions, the yield of radiolabeled (18)F-FBEM was 49.1 ± 2.0 % (based on (18)F-FBA, non-decay corrected). The yield of (18)F-FBEM-Cys(39)-exendin-4 was 35.1 ± 2.6 % (based on the starting (18)F-FBEM, non-decay corrected). The radiochemical purity of (18)F-FBEM-Cys(39)-exendin-4 is >95 %, and the specific activity was at least 35 GBq/μmol. The GLP-1R-positive INS-1 insulinoma xenograft was clearly visible with good contrast to background, whereas GLP-1R-negative MDA-MB435 breast tumor was barely visible. Low levels of radioactivity were also detected at pancreas and lungs due to few GLP-1R expressions. GLP-1R binding specificity was demonstrated by reduced INS-1 tumor uptake of the tracer after coinjection with an excess of unlabeled Cys(39)-exendin-4 at 1 h postinjection. The thiol-reactive reagent, (18)F-FBEM, was prepared with high yield and successfully conjugated to Cys(39)-exendin-4. Favorable preclinical data showing specific and effective tumor targeting by (18)F-FBEM-Cys(39)-exendin-4 suggest that the tracer may be a potential probe for insulinomas imaging.

  8. Acoustic 3D imaging of dental structures

    Energy Technology Data Exchange (ETDEWEB)

    Lewis, D.K. [Lawrence Livermore National Lab., CA (United States); Hume, W.R. [California Univ., Los Angeles, CA (United States); Douglass, G.D. [California Univ., San Francisco, CA (United States)

    1997-02-01

    Our goals for the first year of this three dimensional electodynamic imaging project was to determine how to combine flexible, individual addressable; preprocessing of array source signals; spectral extrapolation or received signals; acoustic tomography codes; and acoustic propagation modeling code. We investigated flexible, individually addressable acoustic array material to find the best match in power, sensitivity and cost and settled on PVDF sheet arrays and 3-1 composite material.

  9. Evaluation of an [18F]AlF-NOTA Analog of Exendin-4 for Imaging of GLP-1 Receptor in Insulinoma

    Directory of Open Access Journals (Sweden)

    Dale O. Kiesewetter, Ning Guo, Jinxia Guo, Haokao Gao, Lei Zhu, Ying Ma, Gang Niu, Xiaoyuan Chen

    2012-01-01

    Full Text Available Introduction: The GLP-1 receptor plays an important role in glucose homeostasis and thus is a very important target for diabetes therapy. The receptor is also overexpressed in insulinoma, a tumor of pancreatic beta-cells. We previously evaluated two fluorine-18-labeled analogs of exendin-4 prepared by conjugation with [18F]FBEM (N-[2-(4-[18F]fluorobenzamideethyl]maleimide. Both compounds demonstrated good tumor uptake, but the synthesis of the radiotracers was time consuming. To overcome this challenge, we developed a NOTA analog and performed radiolabeling using aluminum [18F]fluoride complexation.Methods: Cys40-exendin-4 was conjugated with NOTA mono N-ethylmaleimide. [18F]AlF conjugation was conducted and the radiolabeled product purified by preparative HPLC. Dynamic and static PET imaging scans were conducted on nude mice with established INS-1 xenografts. Uptake of tumor and other major organs in static images was quantitated (%ID/g and comparison with blocking studies was made. PET quantification was also compared with ex vivo biodistribution results.Results: The radiosynthesis provided [18F]AlF-NOTA-MAL-cys40-exendin-4 in 23.6 ± 2.4 % radiochemical yield (uncorrected, n = 3 after HPLC; the process required about 55 min. The specific activity at time of injection ranged from 19.6 to 31.4 GBq (0.53-0.85 Ci/µmol. Tumor uptake had reached its maximum (16.09 ± 1.18% ID/g, n = 4 by 5 min and remained nearly constant for the duration of the study. Kidney uptake continued to increase throughout the entire one hour time course. Pre-injection of exendin-4 caused a marked reduction in tissue uptake with the major exception of liver and kidneys, in which uptake was not affected. HPLC analysis of the radioactive components in extracts of the tumor and plasma showed primarily parent compound at 60 min post-injection, whereas extracts of kidney and urine contained exclusively one polar radioactive component.Conclusion: The radiotracer is prepared in

  10. PET imaging of the brain serotonin transporters (SERT) with N,N-dimethyl-2-(2-amino-4-[{sup 18}F]fluorophenylthio)benzylamine (4-[{sup 18}F]-ADAM) in humans: a preliminary study

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Wen-Sheng [PET Center, Tri-Service General Hospital, Department of Nuclear Medicine, Neihu, Taipei (China); Changhua Christian Hospital, Department of Nuclear Medicine, Changhua (China); Huang, San-Yuan; Ho, Pei-Shen; Yeh, Chin-Bin [Tri-Service General Hospital, Department of Psychiatry, Taipei (China); Ma, Kuo-Hsing [National Defense Medical Center, Department of Biology and Anatomy, Taipei (China); Huang, Ya-Yao; Shiue, Chyng-Yann [PET Center, Tri-Service General Hospital, Department of Nuclear Medicine, Neihu, Taipei (China); PET Center, National Taiwan University Hospital, Department of Nuclear Medicine, Taipei (China); Liu, Ren-Syuan [Taipei Veterans General Hospital, Department of Nuclear Medicine, Taipei (China); Cheng, Cheng-Yi [PET Center, Tri-Service General Hospital, Department of Nuclear Medicine, Neihu, Taipei (China)

    2013-01-15

    The aim of this study was to assess the feasibility of using 4-[{sup 18}F]-ADAM as a brain SERT imaging agent in humans. Enrolled in the study were 19 healthy Taiwanese subjects (11 men, 8 women; age 33 {+-} 9 years). The PET data were semiquantitatively analyzed and expressed as specific uptake ratios (SUR) and distribution volume ratios (DVR) using the software package PMOD. The SUR and DVR of 4-[{sup 18}F]-ADAM in the raphe nucleus (RN), midbrain (MB), thalamus (TH), striatum (STR) and prefrontal cortex (PFC) were determined using the cerebellum (CB) as the reference region. 4-[{sup 18}F]-ADAM bound to known SERT-rich regions in human brain. The order of the regional brain uptake was MB (RN) > TH > STR > PFC > CB. The DVR (n = 4, t* = 60 min) in the RN, TH, STR and PFC were 3.00 {+-} 0.50, 2.25 {+-} 0.45, 2.05 {+-} 0.31 and 1.40 {+-} 0.13, respectively. The optimal time for imaging brain SERT with 4-[{sup 18}F]-ADAM was 120-140 min after injection. At the optimal imaging time, the SURs (n = 15) in the MB, TH, STR, and PFC were 2.25 {+-} 0.20, 2.28 {+-} 0.20, 2.12 {+-} 0.18 and 1.47 {+-} 0.14, respectively. There were no significant differences in SERT availability between men and women (p < 0.05). The results of this study showed that 4-[{sup 18}F]-ADAM was safe for human studies and its distribution in human brain appeared to correlate well with the known distribution of SERT in the human brain. In addition, it had high specific binding and a reasonable optimal time for imaging brain SERT in humans. Thus, 4-[{sup 18}F]-ADAM may be feasible for assessing the status of brain SERT in humans. (orig.)

  11. Synchrotron x-ray imaging of acoustic cavitation bubbles induced by acoustic excitation

    International Nuclear Information System (INIS)

    Jung, Sung Yong; Park, Han Wook; Park, Sung Ho; Lee, Sang Joon

    2017-01-01

    The cavitation induced by acoustic excitation has been widely applied in various biomedical applications because cavitation bubbles can enhance the exchanges of mass and energy. In order to minimize the hazardous effects of the induced cavitation, it is essential to understand the spatial distribution of cavitation bubbles. The spatial distribution of cavitation bubbles visualized by the synchrotron x-ray imaging technique is compared to that obtained with a conventional x-ray tube. Cavitation bubbles with high density in the region close to the tip of the probe are visualized using the synchrotron x-ray imaging technique, however, the spatial distribution of cavitation bubbles in the whole ultrasound field is not detected. In this study, the effects of the ultrasound power of acoustic excitation and working medium on the shape and density of the induced cavitation bubbles are examined. As a result, the synchrotron x-ray imaging technique is useful for visualizing spatial distributions of cavitation bubbles, and it could be used for optimizing the operation conditions of acoustic cavitation. (paper)

  12. Acoustic noise reduction in T 1- and proton-density-weighted turbo spin-echo imaging.

    Science.gov (United States)

    Ott, Martin; Blaimer, Martin; Breuer, Felix; Grodzki, David; Heismann, Björn; Jakob, Peter

    2016-02-01

    To reduce acoustic noise levels in T 1-weighted and proton-density-weighted turbo spin-echo (TSE) sequences, which typically reach acoustic noise levels up to 100 dB(A) in clinical practice. Five acoustic noise reduction strategies were combined: (1) gradient ramps and shapes were changed from trapezoidal to triangular, (2) variable-encoding-time imaging was implemented to relax the phase-encoding gradient timing, (3) RF pulses were adapted to avoid the need for reversing the polarity of the slice-rewinding gradient, (4) readout bandwidth was increased to provide more time for gradient activity on other axes, (5) the number of slices per TR was reduced to limit the total gradient activity per unit time. We evaluated the influence of each measure on the acoustic noise level, and conducted in vivo measurements on a healthy volunteer. Sound recordings were taken for comparison. An overall acoustic noise reduction of up to 16.8 dB(A) was obtained by the proposed strategies (1-4) and the acquisition of half the number of slices per TR only. Image quality in terms of SNR and CNR was found to be preserved. The proposed measures in this study allowed a threefold reduction in the acoustic perception of T 1-weighted and proton-density-weighted TSE sequences compared to a standard TSE-acquisition. This could be achieved without visible degradation of image quality, showing the potential to improve patient comfort and scan acceptability.

  13. An improved synthesis of 4-[18F]-ADAM, a potent serotonin transporter imaging agent

    International Nuclear Information System (INIS)

    Huang, Y.-Y.; Huang, W.-S.; Chu, T.-C.; Shiue, C.-Y.

    2009-01-01

    An improved synthesis of N,N-dimethyl-2-(2-amino-4-[ 18 F]fluorophenylthio)benzylamine (4-[ 18 F]-ADAM, 2) as a potent serotonin transporter (SERT) imaging agent is described. Molecular orbital (MO) calculation predicts that N,N-dimethyl-2- (2-nitro-4-trimethylammoniumtrifluoromethanesulfonylphenylthio)benzamide (8) is probably a better precursor than N,N-dimethyl-2-(2,4-dinitrophenylthio)benzylamine (1) for preparing 2. Radioligand 2 was synthesized by the reaction of either precursor 1 or precursor 8 with K[ 18 F]/K 2.2.2 at 120 deg. C followed by reduction with BH 3 at 80 deg. C. The radiochemical yield (EOB) of 2 synthesized from precursor 1 and 8 was 5.7±2.4% (n=6) and 14.8±4.0% (n=5), respectively, in a synthesis time of 120 min from EOB. The specific activity of 2 was 3 Ci/μmol or 111 GBq/μmol (EOB). Thus, this new synthetic method has significantly improved the radiochemical yield of 4-[ 18 F]-ADAM and makes this radioligand more accessible to PET Centers without a cyclotron.

  14. Deep Water Acoustics

    Science.gov (United States)

    2016-06-28

    the Deep Water project and participate in the NPAL Workshops, including Art Baggeroer (MIT), J. Beron- Vera (UMiami), M. Brown (UMiami), T...Kathleen E . Wage. The North Pacific Acoustic Laboratory deep-water acoustic propagation experiments in the Philippine Sea. J. Acoust. Soc. Am., 134(4...estimate of the angle α during PhilSea09, made from ADCP measurements at the site of the DVLA. Sim. A B1 B2 B3 C D E F Prof. # 0 4 4 4 5 10 16 20 α

  15. Pilot Preclinical and Clinical Evaluation of (4S-4-(3-[18F]Fluoropropyl-L-Glutamate (18F-FSPG for PET/CT Imaging of Intracranial Malignancies.

    Directory of Open Access Journals (Sweden)

    Erik S Mittra

    Full Text Available (S-4-(3-[18F]Fluoropropyl-L-glutamic acid (18F-FSPG is a novel radiopharmaceutical for Positron Emission Tomography (PET imaging. It is a glutamate analogue that can be used to measure xC- transporter activity. This study was performed to assess the feasibility of 18F-FSPG for imaging orthotopic brain tumors in small animals and the translation of this approach in human subjects with intracranial malignancies.For the small animal study, GS9L glioblastoma cells were implanted into brains of Fischer rats and studied with 18F-FSPG, the 18F-labeled glucose derivative 18F-FDG and with the 18F-labeled amino acid derivative 18F-FET. For the human study, five subjects with either primary or metastatic brain cancer were recruited (mean age 50.4 years. After injection of 300 MBq of 18F-FSPG, 3 whole-body PET/Computed Tomography (CT scans were obtained and safety parameters were measured. The three subjects with brain metastases also had an 18F-FDG PET/CT scan. Quantitative and qualitative comparison of the scans was performed to assess kinetics, biodistribution, and relative efficacy of the tracers.In the small animals, the orthotopic brain tumors were visualized well with 18F-FSPG. The high tumor uptake of 18F-FSPG in the GS9L model and the absence of background signal led to good tumor visualization with high contrast (tumor/brain ratio: 32.7. 18F-FDG and 18F-FET showed T/B ratios of 1.7 and 2.8, respectively. In the human pilot study, 18F-FSPG was well tolerated and there was similar distribution in all patients. All malignant lesions were positive with 18F-FSPG except for one low-grade primary brain tumor. In the 18F-FSPG-PET-positive tumors a similar T/B ratio was observed as in the animal model.18F-FSPG is a novel PET radiopharmaceutical that demonstrates good uptake in both small animal and human studies of intracranial malignancies. Future studies on larger numbers of subjects and a wider array of brain tumors are planned.ClinicalTrials.gov NCT

  16. Effect of fMRI acoustic noise on non-auditory working memory task: comparison between continuous and pulsed sound emitting EPI.

    Science.gov (United States)

    Haller, Sven; Bartsch, Andreas J; Radue, Ernst W; Klarhöfer, Markus; Seifritz, Erich; Scheffler, Klaus

    2005-11-01

    Conventional blood oxygenation level-dependent (BOLD) based functional magnetic resonance imaging (fMRI) is accompanied by substantial acoustic gradient noise. This noise can influence the performance as well as neuronal activations. Conventional fMRI typically has a pulsed noise component, which is a particularly efficient auditory stimulus. We investigated whether the elimination of this pulsed noise component in a recent modification of continuous-sound fMRI modifies neuronal activations in a cognitively demanding non-auditory working memory task. Sixteen normal subjects performed a letter variant n-back task. Brain activity and psychomotor performance was examined during fMRI with continuous-sound fMRI and conventional fMRI. We found greater BOLD responses in bilateral medial frontal gyrus, left middle frontal gyrus, left middle temporal gyrus, left hippocampus, right superior frontal gyrus, right precuneus and right cingulate gyrus with continuous-sound compared to conventional fMRI. Conversely, BOLD responses were greater in bilateral cingulate gyrus, left middle and superior frontal gyrus and right lingual gyrus with conventional compared to continuous-sound fMRI. There were no differences in psychomotor performance between both scanning protocols. Although behavioral performance was not affected, acoustic gradient noise interferes with neuronal activations in non-auditory cognitive tasks and represents a putative systematic confound.

  17. Acoustic imaging in a water filled metallic pipe

    International Nuclear Information System (INIS)

    Kolbe, W.F.; Turko, B.T.; Leskovar, B.

    1984-04-01

    A method is described for the imaging of the interior of a water filled metallic pipe using acoustical techniques. The apparatus consists of an array of 20 acoustic transducers mounted circumferentially around the pipe. Each transducer is pulsed in sequence, and the echos resulting from bubbles in the interior are digitized and processed by a computer to generate an image. The electronic control and digitizing system and the software processing of the echo signals are described. The performance of the apparatus is illustrated by the imaging of simulated bubbles consisting of thin walled glass spheres suspended in the pipe

  18. Acoustic imaging in a water filled metallic pipe

    International Nuclear Information System (INIS)

    Kolbe, W.F.; Leskovar, B.; Turko, B.T.

    1985-01-01

    A method is described for the imaging of the interior of a water filled metallic pipe using acoustical techniques. The apparatus consists of an array of 20 acoustic transducers mounted circumferentially around the pipe. Each transducer is pulsed in sequence, and the echos resulting from bubbles in the interior are digitized and processed by a computer to generate an image. The electronic control and digitizing system and the software processing of the echo signals are described. The performance of the apparatus is illustrated by the imaging of simulated bubbles consisting of thin walled glass spheres suspended in the pipe

  19. [18F]fluoromethylated phenyl-pyrroles and 7-azaindole analog as potential dopamine D4 receptor imaging agents

    International Nuclear Information System (INIS)

    Ji, D. Y.; Oh, S. Z.; Choi, Y. S.; Lee, K. C.; Kim, S. E.; Choi, Y.; Lee, K. H.; Kim, B. T.

    1997-01-01

    An association between the dopamine D 4 receptor and schizophrenia was recently suggested and the D 4 receptor antagonists may thus have potential in elucidating the role of the receptor in schizophrenic patients. The purpose of this study was to develop some of these antagonists as potential dopamine D 4 receptor imaging agents for PET. We have prepared 1-(3-[ 18 F]fluoromethylphenyl)-3-([4-(pyridin-2-yl)piperazin-1-yl)methyl) pyrrole (1), 1-(3-[ 18 F]fluoromethylphenyl)-3-([4-(pyridin-2-yl)piperazin-1-yl)methyl) pyrrole (2), and 3-([4-(4-[ 18 F]fluoro methylbenzyl)piperazin-1-yl)methyl)-1H-pyrrolo(2,3,-b)pyridine (3) as potential imaging agents for the dopamine D 4 receptor for PET. The compounds [ 18 F]1 and [ 18 F]2 were prepared by coupling of (3-[ 18 F]fluoromethylphenyl)-pyrrol-1- yl-3-aldehyde and the piperazine moiety in the presence of NaBH 3 CN. The [ 18 F]fluorinated aldehyde was obtained in 60-85% yield by the displacement of the corresponding mesylate with F-18-(THF, 90 .deg. C, 5 min). HPLC purification (Alltech Econosil C-18 columm, 250 x 10 mm, 35: 65 = 0.1M NH 4 CI 2 H : CH 3 OH, 4 ml/min, t R =26.6 min) gave the [ 18 F]1 and [ 18 F]2 in 7-12% yield. In the case of azaindole 3, a methlene link was inserted between the piperazinyl and a fluoromethyl phenyl group. Radiochemical synthesis of the [ 18 F]3 was carried out by coupling of the piperazne moiety and [ 18 F]fluoromethylbenzyl mesylate in the presence of NEt 3 (3:1-CH 3 CN: DMF, 120 .deg. C, 30 min). Purification was carried out by HPLC using a C-18 column (Alltech Econosil, 50 x 10 mm, 100% 0.1M NH 4 CO 2 H for 5 min followed by 40:60=0.1 M NH 4 CO 2 H : MeOH, 4 ml/min t R =28.7 min). The time of synthesis including HPLC purification was 100 min. The overall yield of [ 18 F]3 was 10-15% with a radiochemical purity better than 97% and a specific activity greater than 1000 ci/mmol

  20. Acoustic multimode interference and self-imaging phenomena realized in multimodal phononic crystal waveguides

    International Nuclear Information System (INIS)

    Zou, Qiushun; Yu, Tianbao; Liu, Jiangtao; Wang, Tongbiao; Liao, Qinghua; Liu, Nianhua

    2015-01-01

    We report an acoustic multimode interference effect and self-imaging phenomena in an acoustic multimode waveguide system which consists of M parallel phononic crystal waveguides (M-PnCWs). Results show that the self-imaging principle remains applicable for acoustic waveguides just as it does for optical multimode waveguides. To achieve the dispersions and replicas of the input acoustic waves produced along the propagation direction, we performed the finite element method on M-PnCWs, which support M guided modes within the target frequency range. The simulation results show that single images (including direct and mirrored images) and N-fold images (N is an integer) are identified along the propagation direction with asymmetric and symmetric incidence discussed separately. The simulated positions of the replicas agree well with the calculated values that are theoretically decided by self-imaging conditions based on the guided mode propagation analysis. Moreover, the potential applications based on this self-imaging effect for acoustic wavelength de-multiplexing and beam splitting in the acoustic field are also presented. (paper)

  1. PET imaging of cerebral metabolic change in tinnitus using {sup 18}F-FDG

    Energy Technology Data Exchange (ETDEWEB)

    Jiahe, Tian; Hongtian, Wang; Dayi, Yin; Shulin, Yao; Mingzhe, Shao; Weiyan, Yang; Sichang, Jiang [The PLA General Hospital, Beijing (China)

    2000-11-01

    Tinnitus is an auditory disorder hardly assessable by clinical technology. PET imaging of the brain in 13 cases with and 10 without tinnitus was undertaken at 40 min after injection of 280-440 MBq {sup 18}F-FDG. To ensure the quality of the PET study, all cases followed a normalized procedure with visual and auditory blockage. CT/MRI imaging and routine acoustic tests were carried out in all subjects. PET revealed that an increased uptake of {sup 18}F-FDG at left med-temporal lobe (primary auditory center, PAC) present exclusively in tinnitus, regardless the side of hearing hallucination. Significant asymmetry was noted between left and right PAC, but not at other cortex area. While control cases showed no asymmetric uptake between two hemispheres. The abnormal PAC uptake did not respond to external pure sound stimulus, nor did it relate to the severity of hearing loss assessed by acoustic tests. No anatomical or morphological alteration could be proven on CT/MRI. In conclusion, PET/{sup 18}F-FDG objectively revealed an increased metabolic change at left PAC in tinnitus, which is of diagnostic value; and there is evidence suggesting tinnitus is most likely induced by a functional change in the brain.

  2. Near-field acoustic imaging based on Laplacian sparsity

    DEFF Research Database (Denmark)

    Fernandez Grande, Efren; Daudet, Laurent

    2016-01-01

    We present a sound source identification method for near-field acoustic imaging of extended sources. The methodology is based on a wave superposition method (or equivalent source method) that promotes solutions with sparse higher order spatial derivatives. Instead of promoting direct sparsity......, and the validity of the wave extrapolation used for the reconstruction is examined. It is shown that this methodology can overcome conventional limits of spatial sampling, and is therefore valid for wide-band acoustic imaging of extended sources....

  3. 18F-radiolabeled analogs of exendin-4 for PET imaging of GLP-1 in insulinoma

    International Nuclear Information System (INIS)

    Kiesewetter, Dale O.; Ma, Ying; Niu, Gang; Quan, Qimeng; Guo, Ning; Chen, Xiaoyuan; Gao, Haokao

    2012-01-01

    Glucagon-like peptide type 1 (GLP-1) is an incretin peptide that augments glucose-stimulated insulin release following oral consumption of nutrients. Its message is transmitted via a G protein-coupled receptor called GLP-1R, which is colocalized with pancreatic β-cells. The GLP-1 system is responsible for enhancing insulin release, inhibiting glucagon production, inhibiting hepatic gluconeogenesis, inhibiting gastric mobility, and suppression of appetite. The abundance of GLP-1R in pancreatic β-cells in insulinoma, a cancer of the pancreas, and the activity of GLP-1 in the cardiovascular system have made GLP-1R a target for molecular imaging. We prepared 18 F radioligands for GLP-1R by the reaction of [ 18 F]FBEM, a maleimide prosthetic group, with [Cys 0 ] and [Cys 40 ] analogs of exendin-4. The binding affinity, cellular uptake and internalization, in vitro stability, and uptake and specificity of uptake of the resulting compounds were determined in an INS-1 xenograft model in nude mice. The [ 18 F]FBEM-[Cys x ]-exendin-4 analogs were obtained in good yield (34.3 ± 3.4%, n = 11), based on the starting compound [ 18 F]FBEM, and had a specific activity of 45.51 ± 16.28 GBq/μmol (1.23 ± 0.44 Ci/μmol, n = 7) at the end of synthesis. The C-terminal isomer, [ 18 F]FBEM-[Cys 40 ]-exendin-4, had higher affinity for INS-1 tumor cells (IC 50 1.11 ± 0.057 nM) and higher tumor uptake (25.25 ± 3.39 %ID/g at 1 h) than the N-terminal isomer, [ 18 F]FBEM-[Cys 0 ]-exendin-4 (IC 50 2.99 ± 0.06 nM, uptake 7.20 ± 1.26 %ID/g at 1 h). Uptake of both isomers into INS-1 tumor, pancreas, stomach, and lung could be blocked by preinjection of nonradiolabeled [Cys x ]-exendin-4 (p 18 F]FBEM-[Cys 40 ]-exendin-4 and [ 18 F]FBEM-[Cys 0 ]-exendin-4 have high affinity for GLP-1R and display similar in vitro cell internalization. The higher uptake into INS-1 xenograft tumors exhibited by [ 18 F]FBEM-[Cys 40 ]-exendin-4 suggests that this compound would be the better tracer for imaging

  4. Acoustic Angiography: A New Imaging Modality for Assessing Microvasculature Architecture

    Directory of Open Access Journals (Sweden)

    Ryan C. Gessner

    2013-01-01

    Full Text Available The purpose of this paper is to provide the biomedical imaging community with details of a new high resolution contrast imaging approach referred to as “acoustic angiography.” Through the use of dual-frequency ultrasound transducer technology, images acquired with this approach possess both high resolution and a high contrast-to-tissue ratio, which enables the visualization of microvascular architecture without significant contribution from background tissues. Additionally, volumetric vessel-tissue integration can be visualized by using b-mode overlays acquired with the same probe. We present a brief technical overview of how the images are acquired, followed by several examples of images of both healthy and diseased tissue volumes. 3D images from alternate modalities often used in preclinical imaging, contrast-enhanced micro-CT and photoacoustics, are also included to provide a perspective on how acoustic angiography has qualitatively similar capabilities to these other techniques. These preliminary images provide visually compelling evidence to suggest that acoustic angiography may serve as a powerful new tool in preclinical and future clinical imaging.

  5. Systematic Error of Acoustic Particle Image Velocimetry and Its Correction

    Directory of Open Access Journals (Sweden)

    Mickiewicz Witold

    2014-08-01

    Full Text Available Particle Image Velocimetry is getting more and more often the method of choice not only for visualization of turbulent mass flows in fluid mechanics, but also in linear and non-linear acoustics for non-intrusive visualization of acoustic particle velocity. Particle Image Velocimetry with low sampling rate (about 15Hz can be applied to visualize the acoustic field using the acquisition synchronized to the excitation signal. Such phase-locked PIV technique is described and used in experiments presented in the paper. The main goal of research was to propose a model of PIV systematic error due to non-zero time interval between acquisitions of two images of the examined sound field seeded with tracer particles, what affects the measurement of complex acoustic signals. Usefulness of the presented model is confirmed experimentally. The correction procedure, based on the proposed model, applied to measurement data increases the accuracy of acoustic particle velocity field visualization and creates new possibilities in observation of sound fields excited with multi-tonal or band-limited noise signals.

  6. Magnetic resonance imaging in 38 cases of acoustic tumors

    Energy Technology Data Exchange (ETDEWEB)

    Uchino, Masafumi; Ohtsuka, Takashi; Seiki, Yoshikatsu; Matsumoto, Mikiro; Shibata, Iekado; Terao, Hideo [Toho Univ., Tokyo (Japan). School of Medicine; Kohno, Takeshi; Sanpei, Kenji; Mano, Isamu

    1989-08-01

    The value of magnetic resonance imaging (MRI) in the diagnosis of acoustic tumors was retrospectively assessed in 38 cases. A 0.15 Tesla permanent magnet and a 1.5 Tesla superconducting magnet were employed in 24 and 14 cases, respectively. Gadolinium diethlene triamine pentaacetic acid (Gd-DTPA), a paramagnetic contrast agent, was used in 10 cases. Acoustic tumors were identified in all cases. Small, medium, and large tumors were depicted with equal clarity by MRI and computed tomography (CT). However, tumor contour and extension, accompanying cysts, and brainstem displacement were more clarly visualized on MRI. The use of Gd-DTPA improved the quality of the MR images by markedly enhancing the acoustic tumors in all cases. In particular, detection of small acoustic tumors and intra- or paratumoral cysts was facilitated by the use of Gd-DTPA. The possibility of a correlation between acoustic tumor histology and MRI features was studied by calculation of the contrast to noise (C/N) ratio in 10 cases of acoustic tumor and 7 cases of meningioma. No definite correlation was demonstrated, but there appeared to be some difference in the C/N ratio between acoustic tumors and meningiomas. In three volunteers, MRI demonstrated intracanalicular nerves, separately. Because of its higher resolution, MRI can be expected to replace CT and air CT in the diagnosis of acoustic tumors. (author).

  7. {sup 111}In-anti-F4/80-A3-1 antibody: a novel tracer to image macrophages

    Energy Technology Data Exchange (ETDEWEB)

    Terry, Samantha Y.A. [Radboud University Medical Center, Department of Radiology and Nuclear Medicine, Nijmegen (Netherlands); King' s College London, St Thomas' Hospital, Department of Imaging Chemistry and Biology, London (United Kingdom); Boerman, Otto C.; Gerrits, Danny; Franssen, Gerben M.; Oyen, Wim J.G. [Radboud University Medical Center, Department of Radiology and Nuclear Medicine, Nijmegen (Netherlands); Metselaar, Josbert M. [University of Twente, Targeted Therapeutics, MIRA Institute for Biomedical Technology and Technical Medicine, Enschede (Netherlands); Lehmann, Steffi; Gerdes, Christian A. [Roche Innovation Center Zurich, Roche Pharmaceutical Research and Early Development (pRED), Zurich (Switzerland); Abiraj, Keelara [Roche Innovation Center Basel, Roche Pharmaceutical Research and Early Development (pRED), Basel (Switzerland)

    2015-08-15

    Here, the expression of F4/80 on the cell surface of murine macrophages was exploited to develop a novel imaging tracer that could visualize macrophages in vivo. The immunoreactive fraction and IC{sub 50} of anti-F4/80-A3-1, conjugated with diethylenetriaminepentaacetic acid (DTPA) and radiolabelled with {sup 111}In, were determined in vitro using murine bone marrow-derived macrophages. In vivo biodistribution studies were performed with {sup 111}In-anti-F4/80-A3-1 and isotype-matched control antibody {sup 111}In-rat IgG2b at 24 and 72 h post-injection (p.i.) in SCID/Beige mice bearing orthotopic MDA-MB-231 xenografts. In some studies mice were also treated with liposomal clodronate. Macrophage content in tissues was determined immunohistochemically. Micro-single photon emission computed tomography (SPECT)/CT images were also acquired. In vitro binding assays showed that {sup 111}In-anti-F4/80-A3-1 specifically binds F4/80 receptor-positive macrophages. The immunoreactivity of anti-F4/80-A3-1 was 75 % and IC{sub 50} was 0.58 nM. In vivo, injection of 10 or 100 μg {sup 111}In-anti-F4/80-A3-1 resulted in splenic uptake of 78 %ID/g and 31 %ID/g, respectively, and tumour uptake of 1.38 %ID/g and 4.08 %ID/g, respectively (72 h p.i.). Liposomal clodronate treatment reduced splenic uptake of 10 μg {sup 111}In-anti-F4/80-A3-1 from 248 %ID/g to 114 %ID/g and reduced {sup 111}In-anti-F4/80-A3-1 uptake in the liver and femur (24 h p.i.). Tracer retention in the blood and tumour uptake increased (24 h p.i.). Tumour uptake of {sup 111}In-anti-F4/80-A3-1 was visualized by microSPECT/CT. Macrophage density in the spleen and liver decreased in mice treated with liposomal clodronate. Uptake of {sup 111}In-rat IgG2b was lower in the spleen, liver and femur when compared to {sup 111}In-anti-F4/80-A3-1. Radiolabelled anti-F4/80-A3-1 antibodies specifically localize in tissues infiltrated by macrophages in mice and can be used to visualize tumours. The liver and spleen act as antigen

  8. Non-invasive glucagon-like peptide-1 receptor imaging in pancreas with (18)F-Al labeled Cys(39)-exendin-4.

    Science.gov (United States)

    Mi, Baoming; Xu, Yuping; Pan, Donghui; Wang, Lizhen; Yang, Runlin; Yu, Chunjing; Wan, Weixing; Wu, Yiwei; Yang, Min

    2016-02-26

    Glucagon-like peptide-1 receptor (GLP-1R) is abundantly expressed on beta cells and may be an ideal target for the pancreas imaging. Monitoring the GLP-1R of pancreas could be benefit for understanding the pathophysiology of diabetes. In the present study, (18)F-Al labeled exendin-4 analog, (18)F-Al-NOTA-MAL-Cys(39)-exendin-4, was evaluated for PET imaging GLP-1R in the pancreas. The targeting of (18)F-Al labeled exendin-4 analog was examined in healthy and streptozotocin induced diabetic rats. Rats were injected with (18)F-Al-NOTA-MAL-Cys(39)-exendin-4 and microPET imaging was performed at 1 h postinjection, followed by ex vivo biodistribution. GLP-1R expression in pancreas was determined through post mortern examinations. The pancreas of healthy rats was readily visualized after administration of (18)F-Al-NOTA-MAL-Cys(39)-exendin-4, whereas the pancreas of diabetic rats, as well as those from rats co-injected with excess of unlabeled peptides, was barely visible by microPET. At 60 min postinjection, the pancreatic uptakes were 1.02 ± 0.15%ID/g and 0.23 ± 0.05%ID/g in healthy and diabetic rats respectively. Under block, the pancreatic uptakes of non-diabetic rats reduced to 0.21 ± 0.07%ID/g at the same time point. Biodistribution data and IHC staining confirmed the findings of the microPET imaging. The favorable preclinical data indicated that (18)F-Al-NOTA-MAL-Cys(39)-exendin-4may be suitable for non-invasive monitoring functional pancreatic beta cells. Copyright © 2016 Elsevier Inc. All rights reserved.

  9. Combination of acoustical radiosity and the image source method

    DEFF Research Database (Denmark)

    Koutsouris, Georgios I; Brunskog, Jonas; Jeong, Cheol-Ho

    2013-01-01

    A combined model for room acoustic predictions is developed, aiming to treat both diffuse and specular reflections in a unified way. Two established methods are incorporated: acoustical radiosity, accounting for the diffuse part, and the image source method, accounting for the specular part...

  10. Imaging and detection of mines from acoustic measurements

    Science.gov (United States)

    Witten, Alan J.; DiMarzio, Charles A.; Li, Wen; McKnight, Stephen W.

    1999-08-01

    A laboratory-scale acoustic experiment is described where a buried target, a hockey puck cut in half, is shallowly buried in a sand box. To avoid the need for source and receiver coupling to the host sand, an acoustic wave is generated in the subsurface by a pulsed laser suspended above the air-sand interface. Similarly, an airborne microphone is suspended above this interface and moved in unison with the laser. After some pre-processing of the data, reflections for the target, although weak, could clearly be identified. While the existence and location of the target can be determined by inspection of the data, its unique shape can not. Since target discrimination is important in mine detection, a 3D imaging algorithm was applied to the acquired acoustic data. This algorithm yielded a reconstructed image where the shape of the target was resolved.

  11. An improved synthesis of 4-[{sup 18}F]-ADAM, a potent serotonin transporter imaging agent

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Y.-Y. [PET Center, Department of Nuclear Medicine, Tri-Service General Hospital 325 Section 2, Cheng-Kung Road, Neihu 114, Taipei, Taiwan (China); Department of Biomedical Engineering and Environmental Sciences, National Thising Hua University, 101, Section 2, Kuang-Fu Road, Hsinchu 30013, Taiwan (China); Huang, W.-S. [PET Center, Department of Nuclear Medicine, Tri-Service General Hospital 325 Section 2, Cheng-Kung Road, Neihu 114, Taipei, Taiwan (China); Chu, T.-C. [Department of Biomedical Engineering and Environmental Sciences, National Thising Hua University, 101, Section 2, Kuang-Fu Road, Hsinchu 30013, Taiwan (China); Shiue, C.-Y. [PET Center, Department of Nuclear Medicine, Tri-Service General Hospital 325 Section 2, Cheng-Kung Road, Neihu 114, Taipei, Taiwan (China)], E-mail: shiue@ndmctsgh.edu.tw

    2009-06-15

    An improved synthesis of N,N-dimethyl-2-(2-amino-4-[{sup 18}F]fluorophenylthio)benzylamine (4-[{sup 18}F]-ADAM, 2) as a potent serotonin transporter (SERT) imaging agent is described. Molecular orbital (MO) calculation predicts that N,N-dimethyl-2- (2-nitro-4-trimethylammoniumtrifluoromethanesulfonylphenylthio)benzamide (8) is probably a better precursor than N,N-dimethyl-2-(2,4-dinitrophenylthio)benzylamine (1) for preparing 2. Radioligand 2 was synthesized by the reaction of either precursor 1 or precursor 8 with K[{sup 18}F]/K{sub 2.2.2} at 120 deg. C followed by reduction with BH{sub 3} at 80 deg. C. The radiochemical yield (EOB) of 2 synthesized from precursor 1 and 8 was 5.7{+-}2.4% (n=6) and 14.8{+-}4.0% (n=5), respectively, in a synthesis time of 120 min from EOB. The specific activity of 2 was 3 Ci/{mu}mol or 111 GBq/{mu}mol (EOB). Thus, this new synthetic method has significantly improved the radiochemical yield of 4-[{sup 18}F]-ADAM and makes this radioligand more accessible to PET Centers without a cyclotron.

  12. Sci-Thur AM: YIS – 02: Imaging dose distributions through the detection of radiation-induced acoustic waves

    Energy Technology Data Exchange (ETDEWEB)

    Hickling, Susannah; Lei, Hao; Hobson, Maritza; Leger, Pierre; Wang, Xueding; El Naqa, Issam [University of Michigan, McGill University, McGill University , University of Michigan, University of Michigan/McGill University (United States)

    2016-08-15

    Purpose: X-ray acoustic computed tomography (XACT) is an emerging technique that images the dose deposited within an object following linac irradiation by detecting acoustic waves induced via the photoacoustic effect. This work shows that XACT images can be formed in soft-tissue equivalent material and that dosimetric information can be extracted from such images. Methods: Acoustic waves induced in a water tank following irradiation by a 10 MV flattening filter free photon beam were detected with an immersion ultrasound transducer at 60 angles surrounding the radiation field. A back-projection algorithm was used to reconstruct an XACT image from the detected transducer signals. Profiles extracted from XACT images were compared to profiles measured with ion chambers as per the current clinical protocol. Results: XACT images were successfully formed of simple 4 cm × 4 cm and 6 cm × 3 cm fields, as well as of more complicated multi-leaf collimator defined fields. For the 6 cm × 3 cm field, 74% and 87% of the XACT profile points in the 6 cm and 3 cm dimensions, respectively, passed a 7% / 4 mm gamma test when compared to ion chamber measurements. In a complicated puzzle piece shaped field, 86% of the pixels in an extracted profile passed a 7% / 4 mm gamma test. Conclusions: XACT is capable of imaging the dose distribution delivered by a variety of field sizes and shapes in water, and is a viable technique for both water tank and in vivo dosimetry.

  13. {sup 18}F-radiolabeled analogs of exendin-4 for PET imaging of GLP-1 in insulinoma

    Energy Technology Data Exchange (ETDEWEB)

    Kiesewetter, Dale O.; Ma, Ying; Niu, Gang; Quan, Qimeng; Guo, Ning; Chen, Xiaoyuan [National Institute of Biomedical Imaging and Bioengineering (NIBIB), National Institutes of Health (NIH), Laboratory of Molecular Imaging and Nanomedicine (LOMIN), Bethesda, MD (United States); Gao, Haokao [National Institute of Biomedical Imaging and Bioengineering (NIBIB), National Institutes of Health (NIH), Laboratory of Molecular Imaging and Nanomedicine (LOMIN), Bethesda, MD (United States); Fourth Military Medical University, Department of Cardiology, Xijing Hospital, Xi' an (China)

    2012-03-15

    Glucagon-like peptide type 1 (GLP-1) is an incretin peptide that augments glucose-stimulated insulin release following oral consumption of nutrients. Its message is transmitted via a G protein-coupled receptor called GLP-1R, which is colocalized with pancreatic {beta}-cells. The GLP-1 system is responsible for enhancing insulin release, inhibiting glucagon production, inhibiting hepatic gluconeogenesis, inhibiting gastric mobility, and suppression of appetite. The abundance of GLP-1R in pancreatic {beta}-cells in insulinoma, a cancer of the pancreas, and the activity of GLP-1 in the cardiovascular system have made GLP-1R a target for molecular imaging. We prepared {sup 18}F radioligands for GLP-1R by the reaction of [{sup 18}F]FBEM, a maleimide prosthetic group, with [Cys{sup 0}] and [Cys{sup 40}] analogs of exendin-4. The binding affinity, cellular uptake and internalization, in vitro stability, and uptake and specificity of uptake of the resulting compounds were determined in an INS-1 xenograft model in nude mice. The [{sup 18}F]FBEM-[Cys{sup x}]-exendin-4 analogs were obtained in good yield (34.3 {+-} 3.4%, n = 11), based on the starting compound [{sup 18}F]FBEM, and had a specific activity of 45.51 {+-} 16.28 GBq/{mu}mol (1.23 {+-} 0.44 Ci/{mu}mol, n = 7) at the end of synthesis. The C-terminal isomer, [{sup 18}F]FBEM-[Cys{sup 40}]-exendin-4, had higher affinity for INS-1 tumor cells (IC{sub 50} 1.11 {+-} 0.057 nM) and higher tumor uptake (25.25 {+-} 3.39 %ID/g at 1 h) than the N-terminal isomer, [{sup 18}F]FBEM-[Cys{sup 0}]-exendin-4 (IC{sub 50} 2.99 {+-} 0.06 nM, uptake 7.20 {+-} 1.26 %ID/g at 1 h). Uptake of both isomers into INS-1 tumor, pancreas, stomach, and lung could be blocked by preinjection of nonradiolabeled [Cys{sup x}]-exendin-4 (p < 0.05). [{sup 18}F]FBEM-[Cys{sup 40}]-exendin-4 and [{sup 18}F]FBEM-[Cys{sup 0}]-exendin-4 have high affinity for GLP-1R and display similar in vitro cell internalization. The higher uptake into INS-1 xenograft tumors

  14. From prosodic structure to acoustic saliency: A fMRI investigation of speech rate, clarity, and emphasis

    Science.gov (United States)

    Golfinopoulos, Elisa

    Acoustic variability in fluent speech can arise at many stages in speech production planning and execution. For example, at the phonological encoding stage, the grouping of phonemes into syllables determines which segments are coarticulated and, by consequence, segment-level acoustic variation. Likewise phonetic encoding, which determines the spatiotemporal extent of articulatory gestures, will affect the acoustic detail of segments. Functional magnetic resonance imaging (fMRI) was used to measure brain activity of fluent adult speakers in four speaking conditions: fast, normal, clear, and emphatic (or stressed) speech. These speech manner changes typically result in acoustic variations that do not change the lexical or semantic identity of productions but do affect the acoustic saliency of phonemes, syllables and/or words. Acoustic responses recorded inside the scanner were assessed quantitatively using eight acoustic measures and sentence duration was used as a covariate of non-interest in the neuroimaging analysis. Compared to normal speech, emphatic speech was characterized acoustically by a greater difference between stressed and unstressed vowels in intensity, duration, and fundamental frequency, and neurally by increased activity in right middle premotor cortex and supplementary motor area, and bilateral primary sensorimotor cortex. These findings are consistent with right-lateralized motor planning of prosodic variation in emphatic speech. Clear speech involved an increase in average vowel and sentence durations and average vowel spacing, along with increased activity in left middle premotor cortex and bilateral primary sensorimotor cortex. These findings are consistent with an increased reliance on feedforward control, resulting in hyper-articulation, under clear as compared to normal speech. Fast speech was characterized acoustically by reduced sentence duration and average vowel spacing, and neurally by increased activity in left anterior frontal

  15. Value of 18F-3,4-dihydroxyphenylalanine PET/MR image fusion in pediatric supratentorial infiltrative astrocytomas: a prospective pilot study.

    Science.gov (United States)

    Morana, Giovanni; Piccardo, Arnoldo; Milanaccio, Claudia; Puntoni, Matteo; Nozza, Paolo; Cama, Armando; Zefiro, Daniele; Cabria, Massimo; Rossi, Andrea; Garrè, Maria Luisa

    2014-05-01

    Infiltrative astrocytomas (IAs) represent a group of astrocytic gliomas ranging from low-grade to highly malignant, characterized by diffuse invasion of the brain parenchyma. When compared with their adult counterpart, pediatric IAs may be considered biologically distinct entities; nevertheless, similarly to those in adults they represent a complex oncologic challenge. The aim of this study was to investigate the diagnostic role, clinical contribution, and prognostic value of fused (18)F-3,4-dihydroxyphenylalanine ((18)F-DOPA) PET/MR images in pediatric supratentorial IAs. Pediatric patients with supratentorial IAs involving at least 2 cerebral lobes, either newly diagnosed or with suspected disease progression, prospectively underwent (18)F-DOPA PET and conventional MR imaging, performed within 10 d of each other. (18)F-DOPA PET data were interpreted qualitatively and semiquantitatively, fusing images with MR images. PET scans were classified as positive if tumors identified on MR imaging exhibited tracer uptake above the level of the corresponding contralateral normal brain. Maximum standardized uptake values, tumor-to-normal contralateral tissue ratios, and tumor-to-normal striatum ratios were calculated for all tumors. Correlations between the degree and extent of (18)F-DOPA uptake, MR imaging tumor characteristics, and histologic results were investigated. The contribution of (18)F-DOPA PET/MR image fusion was considered relevant if it enabled one to select the most appropriate biopsy site, discriminate between disease progression and treatment-related changes, or influence treatment strategy. The patient's outcome was finally correlated with (18)F-DOPA uptake. Thirteen patients (8 boys and 5 girls) were included (5 diffuse astrocytomas, 2 anaplastic astrocytomas, 5 gliomatosis cerebri, and 1 glioblastoma multiforme). The (18)F-DOPA uptake pattern was heterogeneous in all positive scans (9/13), revealing metabolic heterogeneities within each tumor. Significant

  16. High throughput imaging cytometer with acoustic focussing.

    Science.gov (United States)

    Zmijan, Robert; Jonnalagadda, Umesh S; Carugo, Dario; Kochi, Yu; Lemm, Elizabeth; Packham, Graham; Hill, Martyn; Glynne-Jones, Peter

    2015-10-31

    We demonstrate an imaging flow cytometer that uses acoustic levitation to assemble cells and other particles into a sheet structure. This technique enables a high resolution, low noise CMOS camera to capture images of thousands of cells with each frame. While ultrasonic focussing has previously been demonstrated for 1D cytometry systems, extending the technology to a planar, much higher throughput format and integrating imaging is non-trivial, and represents a significant jump forward in capability, leading to diagnostic possibilities not achievable with current systems. A galvo mirror is used to track the images of the moving cells permitting exposure times of 10 ms at frame rates of 50 fps with motion blur of only a few pixels. At 80 fps, we demonstrate a throughput of 208 000 beads per second. We investigate the factors affecting motion blur and throughput, and demonstrate the system with fluorescent beads, leukaemia cells and a chondrocyte cell line. Cells require more time to reach the acoustic focus than beads, resulting in lower throughputs; however a longer device would remove this constraint.

  17. Magnetic resonance imaging of acoustic neurinomas

    International Nuclear Information System (INIS)

    Umezu, Hiromichi; Seki, Yojiro; Aiba, Tadashi; Takemori, Setsuko

    1991-01-01

    A restrospective review was made on magnetic resonance imaging (MRI) scans, preoperative neuro-otological findings, and surgical results for hearing preservation in 20 consecutive patients with histologically verified acoustic neurinomas. The maximum diameter of the tumor, both in the cerebellopontine angle (CPA) and internal auditory canal (IAC), were measured by MRI scans to classify tumor size. The signal intensity of acoustic neurinoma was equal to or lower than that of the adjacent pons on T 1 -weighted images and higher on T 2 -weighted images. After the administration of Gd-DTPA, tumors were markedly enhanced, which appeared homogeneous for small tumors and heterogeneous for large ones. There was no relationship between the degree of preoperative hearing loss and tumor size in either the CPA or the IAC. The larger the tumor in the CPA, however, the more often did the response to a caloric test disappear or decrease greatly. In contrast, there was no apparent correlation between the caloric response and tumor size in the IAC. Twelve patients (60%) had serviceable hearing (pure tone average loss 50%) preoperatively: the average tumor size in this group was similar to that in patients with poor or no hearing. These 12 patients were considered to be candidates for hearing preservation at surgery: 5 (41.7%) retained serviceable hearing postoperatively. A mean tumor size in the CPA was 11.8 mm for patients with postoperative serviceable hearing and 21.3 mm for those without it. Moreover, hearing was preserved postoperatively in all 4 patients with tumor less than 5 mm in the IAC. Thus, hearing preservation after surgery seemed to be closely related to tumor size. This study confirmed the value of MRI, providing information for the evaluation of hearing-preservation surgery. (N.K.)

  18. ¹¹¹In-anti-F4/80-A3-1 antibody: a novel tracer to image macrophages.

    Science.gov (United States)

    Terry, Samantha Y A; Boerman, Otto C; Gerrits, Danny; Franssen, Gerben M; Metselaar, Josbert M; Lehmann, Steffi; Oyen, Wim J G; Gerdes, Christian A; Abiraj, Keelara

    2015-08-01

    Here, the expression of F4/80 on the cell surface of murine macrophages was exploited to develop a novel imaging tracer that could visualize macrophages in vivo. The immunoreactive fraction and IC50 of anti-F4/80-A3-1, conjugated with diethylenetriaminepentaacetic acid (DTPA) and radiolabelled with (111)In, were determined in vitro using murine bone marrow-derived macrophages. In vivo biodistribution studies were performed with (111)In-anti-F4/80-A3-1 and isotype-matched control antibody (111)In-rat IgG2b at 24 and 72 h post-injection (p.i.) in SCID/Beige mice bearing orthotopic MDA-MB-231 xenografts. In some studies mice were also treated with liposomal clodronate. Macrophage content in tissues was determined immunohistochemically. Micro-single photon emission computed tomography (SPECT)/CT images were also acquired. In vitro binding assays showed that (111)In-anti-F4/80-A3-1 specifically binds F4/80 receptor-positive macrophages. The immunoreactivity of anti-F4/80-A3-1 was 75 % and IC50 was 0.58 nM. In vivo, injection of 10 or 100 μg (111)In-anti-F4/80-A3-1 resulted in splenic uptake of 78 %ID/g and 31 %ID/g, respectively, and tumour uptake of 1.38 %ID/g and 4.08 %ID/g, respectively (72 h p.i.). Liposomal clodronate treatment reduced splenic uptake of 10 μg (111)In-anti-F4/80-A3-1 from 248 %ID/g to 114 %ID/g and reduced (111)In-anti-F4/80-A3-1 uptake in the liver and femur (24 h p.i.). Tracer retention in the blood and tumour uptake increased (24 h p.i.). Tumour uptake of (111)In-anti-F4/80-A3-1 was visualized by microSPECT/CT. Macrophage density in the spleen and liver decreased in mice treated with liposomal clodronate. Uptake of (111)In-rat IgG2b was lower in the spleen, liver and femur when compared to (111)In-anti-F4/80-A3-1. Radiolabelled anti-F4/80-A3-1 antibodies specifically localize in tissues infiltrated by macrophages in mice and can be used to visualize tumours. The liver and spleen act as antigen sink organs for macrophage-specific tracers.

  19. Description and validation of a combination of acoustical radiosity and the image source method

    DEFF Research Database (Denmark)

    Marbjerg, Gerd Høy; Jeong, Cheol-Ho; Brunskog, Jonas

    2014-01-01

    A model that combines image source modelling and acoustical radiosity with complex boundary con- ditions, thus including phase shifts on reflection, has been developed. The model is denoted Phased Acoustical Radiosity and Image Source Model (PARISM). It has been developed in order to be able...... to model both specular and diffuse reflections with complex-valued acoustical descriptions of the surfaces. This paper mainly describes the combination of the two models and the implementation of the angle dependent surface descriptions both in the image source model and in acoustical radiosity...

  20. Acoustic resonances in microfluidic chips: full-image micro-PIV experiments and numerical simulations.

    Science.gov (United States)

    Hagsäter, S M; Jensen, T Glasdam; Bruus, H; Kutter, J P

    2007-10-01

    We show that full-image micro-PIV analysis in combination with images of transient particle motion is a powerful tool for experimental studies of acoustic radiation forces and acoustic streaming in microfluidic chambers under piezo-actuation in the MHz range. The measured steady-state motion of both large 5 microm and small 1 microm particles can be understood in terms of the acoustic eigenmodes or standing ultra-sound waves in the given experimental microsystems. This interpretation is supported by numerical solutions of the corresponding acoustic wave equation.

  1. Characterization of 4-[18F]-ADAM as an imaging agent for SERT in non-human primate brain using PET: a dynamic study

    International Nuclear Information System (INIS)

    Chen, Yu-An; Huang, Wen-Sheng; Lin, Yaoh-Shiang; Cheng, Cheng-Yi; Liu, Ren-Shyan; Wang, Shyh-Jen; Li, I-Hsun; Huang, San-Yuan; Shiue, Chyng-Yann; Chen, Cheng-Yu; Ma, Kuo-Hsing

    2012-01-01

    Introduction: Serotonin transporter (SERT) has been associated with many psychiatric diseases. This study investigated the biodistribution of a serotonin transporter imaging agent, N,N-dimethyl-2-(2-amino-4- 18 F-fluorophenylthio)benzylamine (4-[ 18 F]-ADAM), in nonhuman primate brain using positron emission tomography (PET). Methods: Six and four Macaca cyclopis monkeys were used to determine the transit time (i.e., time necessary to reach biodistribution equilibrium) and the reproducibility of 4-[ 18 F]-ADAM biodistribution in the brain, respectively. The sensitivity and specificity of 4-[ 18 F]-ADAM binding to SERT were evaluated in one monkey challenged with different doses of fluoxetine and one monkey treated with 3,4-methylendioxymethamphetamine (MDMA). Dynamic PET imaging was performed for 3 h after 4-[ 18 F]-ADAM intravenous bolus injection. The specific uptake ratios (SURs) in the midbrain (MB), thalamus (TH), striatum (ST) and frontal cortex (FC) were calculated. Results: The distribution of 4-[ 18 F]-ADAM reached equilibrium 120–150 min after injection. The mean SURs were 2.49±0.13 in MB, 1.59±0.17 in TH, 1.35±0.06 in ST and 0.34±0.03 in FC, and the minimum variability was shown 120–150 min after 4-[ 18 F]-ADAM injection. Using SURs and intraclass coefficient of correlation, the test/retest variability was under 8% and above 0.8, respectively, in SERT-rich areas. Challenge with fluoxetin (0.75–2 mg) dose-dependently inhibited the SURs in various brain regions. 4-[ 18 F]-ADAM binding was markedly reduced in the brain of an MDMA-treated monkey compared to that in brains of normal controls. Conclusion: 4-[ 18 F]-ADAM appears to be a highly selective radioligand for imaging SERT in monkey brain.

  2. Photo acoustic imaging: technology, systems and market trends

    Science.gov (United States)

    Faucheux, Marc; d'Humières, Benoît; Cochard, Jacques

    2017-03-01

    Although the Photo Acoustic effect was observed by Graham Bell in 1880, the first applications (gas analysis) occurred in 1970's using the required energetic light pulses from lasers. During mid 1990's medical imaging research begun to use Photo Acoustic effect and in vivo images were obtained in mid-2000. Since 2009, the number of patent related to Photo Acoustic Imaging (PAI) has dramatically increased. PAI machines for pre-clinical and small animal imaging have been being used in a routine way for several years. Based on its very interesting features (non-ionizing radiation, noninvasive, high depth resolution ratio, scalability, moderate price) and because it is able to deliver not only anatomical, but functional and molecular information, PAI is a very promising clinical imaging modality. It penetrates deeper into tissue than OCT (Optical Coherence Tomography) and provides a higher resolution than ultrasounds. The PAI is one of the most growing imaging modality and some innovative clinical systems are planned to be on market in 2017. Our study analyzes the different approaches such as photoacoustic computed tomography, 3D photoacoustic microscopy, multispectral photoacoustic tomography and endoscopy with the recent and tremendous technological progress over the past decade: advances in image reconstruction algorithms, laser technology, ultrasound detectors and miniaturization. We analyze which medical domains and applications are the most concerned and explain what should be the forthcoming medical system in the near future. We segment the market in four parts: Components and R&D, pre-clinical, analytics, clinical. We analyzed what should be, quantitatively and qualitatively, the PAI medical markets in each segment and its main trends. We point out the market accessibility (patents, regulations, clinical evaluations, clinical acceptance, funding). In conclusion, we explain the main market drivers and challenges to overcome and give a road map for medical

  3. NaGdF4:Nd3+/Yb3+ Nanoparticles as Multimodal Imaging Agents

    Science.gov (United States)

    Pedraza, Francisco; Rightsell, Chris; Kumar, Ga; Giuliani, Jason; Monton, Car; Sardar, Dhiraj

    Medical imaging is a fundamental tool used for the diagnosis of numerous ailments. Each imaging modality has unique advantages; however, they possess intrinsic limitations. Some of which include low spatial resolution, sensitivity, penetration depth, and radiation damage. To circumvent this problem, the combination of imaging modalities, or multimodal imaging, has been proposed, such as Near Infrared Fluorescence imaging (NIRF) and Magnetic Resonance Imaging (MRI). Combining individual advantages, specificity and selectivity of NIRF with the deep penetration and high spatial resolution of MRI, it is possible to circumvent their shortcomings for a more robust imaging technique. In addition, both imaging modalities are very safe and minimally invasive. Fluorescent nanoparticles, such as NaGdF4:Nd3 +/Yb3 +, are excellent candidates for NIRF/MRI multimodal imaging. The dopants, Nd and Yb, absorb and emit within the biological window; where near infrared light is less attenuated by soft tissue. This results in less tissue damage and deeper tissue penetration making it a viable candidate in biological imaging. In addition, the inclusion of Gd results in paramagnetic properties, allowing their use as contrast agents in multimodal imaging. The work presented will include crystallographic results, as well as full optical and magnetic characterization to determine the nanoparticle's viability in multimodal imaging.

  4. Negative refraction imaging of acoustic metamaterial lens in the supersonic range

    Directory of Open Access Journals (Sweden)

    Jianning Han

    2014-05-01

    Full Text Available Acoustic metamaterials with negative refraction index is the most promising method to overcome the diffraction limit of acoustic imaging to achieve ultrahigh resolution. In this paper, we use localized resonant phononic crystal as the unit cell to construct the acoustic negative refraction lens. Based on the vibration model of the phononic crystal, negative quality parameters of the lens are obtained while excited near the system resonance frequency. Simulation results show that negative refraction of the acoustic lens can be achieved when a sound wave transmiting through the phononic crystal plate. The patterns of the imaging field agree well with that of the incident wave, while the dispersion is very weak. The unit cell size in the simulation is 0.0005 m and the wavelength of the sound source is 0.02 m, from which we show that acoustic signal can be manipulated through structures with dimensions much smaller than the wavelength of incident wave.

  5. 4th Pacific Rim Underwater Acoustics Conference

    CERN Document Server

    Xu, Wen; Cheng, Qianliu; Zhao, Hangfang

    2016-01-01

    These proceedings are a collection of 16 selected scientific papers and reviews by distinguished international experts that were presented at the 4th Pacific Rim Underwater Acoustics Conference (PRUAC), held in Hangzhou, China in October 2013. The topics discussed at the conference include internal wave observation and prediction; environmental uncertainty and coupling to sound propagation; environmental noise and ocean dynamics; dynamic modeling in acoustic fields; acoustic tomography and ocean parameter estimation; time reversal and matched field processing; underwater acoustic localization and communication as well as measurement instrumentations and platforms. These proceedings provide insights into the latest developments in underwater acoustics, promoting the exchange of ideas for the benefit of future research.

  6. Non-invasive glucagon-like peptide-1 receptor imaging in pancreas with {sup 18}F-Al labeled Cys{sup 39}-exendin-4

    Energy Technology Data Exchange (ETDEWEB)

    Mi, Baoming [Department of Nuclear Medicine, The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu, 215006 (China); Department of Nuclear Medicine, Affiliated Hospital of Jiangnan University (Wuxi 4th People' s Hospital), Wuxi, Jiangsu, 214062 (China); Xu, Yuping [Key Laboratory of Nuclear Medicine, Ministry of Health, Jiangsu Key Laboratory of Molecular Nuclear Medicine, Jiangsu Institute of Nuclear Medicine, Wuxi, Jiangsu, 214063 (China); Nanjing Medical University, Nanjing, Jiangsu, 210029 (China); Pan, Donghui; Wang, Lizhen; Yang, Runlin [Key Laboratory of Nuclear Medicine, Ministry of Health, Jiangsu Key Laboratory of Molecular Nuclear Medicine, Jiangsu Institute of Nuclear Medicine, Wuxi, Jiangsu, 214063 (China); Yu, Chunjing; Wan, Weixing [Department of Nuclear Medicine, Affiliated Hospital of Jiangnan University (Wuxi 4th People' s Hospital), Wuxi, Jiangsu, 214062 (China); Wu, Yiwei, E-mail: wuyiwei3988@gmail.com [Department of Nuclear Medicine, The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu, 215006 (China); Yang, Min, E-mail: ymzfk@yahoo.com.hk [Key Laboratory of Nuclear Medicine, Ministry of Health, Jiangsu Key Laboratory of Molecular Nuclear Medicine, Jiangsu Institute of Nuclear Medicine, Wuxi, Jiangsu, 214063 (China); Nanjing Medical University, Nanjing, Jiangsu, 210029 (China)

    2016-02-26

    Purpose: Glucagon-like peptide-1 receptor (GLP-1R) is abundantly expressed on beta cells and may be an ideal target for the pancreas imaging. Monitoring the GLP-1R of pancreas could be benefit for understanding the pathophysiology of diabetes. In the present study, {sup 18}F-Al labeled exendin-4 analog, {sup 18}F-Al-NOTA-MAL-Cys{sup 39}-exendin-4, was evaluated for PET imaging GLP-1R in the pancreas. Methods: The targeting of {sup 18}F-Al labeled exendin-4 analog was examined in healthy and streptozotocin induced diabetic rats. Rats were injected with {sup 18}F-Al-NOTA-MAL-Cys{sup 39}-exendin-4 and microPET imaging was performed at 1 h postinjection, followed by ex vivo biodistribution. GLP-1R expression in pancreas was determined through post mortern examinations. Results: The pancreas of healthy rats was readily visualized after administration of {sup 18}F-Al-NOTA-MAL-Cys{sup 39}-exendin-4, whereas the pancreas of diabetic rats, as well as those from rats co-injected with excess of unlabeled peptides, was barely visible by microPET. At 60 min postinjection, the pancreatic uptakes were 1.02 ± 0.15%ID/g and 0.23 ± 0.05%ID/g in healthy and diabetic rats respectively. Under block, the pancreatic uptakes of non-diabetic rats reduced to 0.21 ± 0.07%ID/g at the same time point. Biodistribution data and IHC staining confirmed the findings of the microPET imaging. Conclusion: The favorable preclinical data indicated that {sup 18}F-Al-NOTA-MAL-Cys{sup 39}-exendin-4may be suitable for non-invasive monitoring functional pancreatic beta cells.

  7. Platforms for hyperspectral imaging, in-situ optical and acoustical imaging in urbanized regions

    Science.gov (United States)

    Bostater, Charles R.; Oney, Taylor

    2016-10-01

    Hyperspectral measurements of the water surface of urban coastal waters are presented. Oblique bidirectional reflectance factor imagery was acquired made in a turbid coastal sub estuary of the Indian River Lagoon, Florida and along coastal surf zone waters of the nearby Atlantic Ocean. Imagery was also collected using a pushbroom hyperspectral imager mounted on a fixed platform with a calibrated circular mechatronic rotation stage. Oblique imagery of the shoreline and subsurface features clearly shows subsurface bottom features and rip current features within the surf zone water column. In-situ hyperspectral optical signatures were acquired from a vessel as a function of depth to determine the attenuation spectrum in Palm Bay. A unique stationary platform methodology to acquire subsurface acoustic images showing the presence of moving bottom boundary nephelometric layers passing through the acoustic fan beam. The acoustic fan beam imagery indicated the presence of oscillatory subsurface waves in the urbanized coastal estuary. Hyperspectral imaging using the fixed platform techniques are being used to collect hyperspectral bidirectional reflectance factor (BRF) measurements from locations at buildings and bridges in order to provide new opportunities to advance our scientific understanding of aquatic environments in urbanized regions.

  8. A Treatise on Acoustic Radiation. Volume 2. Acoustic Transducers

    Science.gov (United States)

    1983-01-01

    Newton) V (meter/sec) acoustical p (Newton/meter2 ) U (meter 3/sec) To display Eq. 1.53.1 in simple form we take time to be given by exp(- iot ) and choose...if all the C-component edges and e-drivers are in the tree, all the L-component "A edges and idrivers are in the cotree, all the algebraic equations...momentum and mass of the elastic field then become, (a) Al - V -T + F 278 W-4. ,-,- * * * 4 % • *.• Design of Acoustic Transducers IOT (b) I + VV-s

  9. Performance Evaluation of a Biometric System Based on Acoustic Images

    Science.gov (United States)

    Izquierdo-Fuente, Alberto; del Val, Lara; Jiménez, María I.; Villacorta, Juan J.

    2011-01-01

    An acoustic electronic scanning array for acquiring images from a person using a biometric application is developed. Based on pulse-echo techniques, multifrequency acoustic images are obtained for a set of positions of a person (front, front with arms outstretched, back and side). Two Uniform Linear Arrays (ULA) with 15 λ/2-equispaced sensors have been employed, using different spatial apertures in order to reduce sidelobe levels. Working frequencies have been designed on the basis of the main lobe width, the grating lobe levels and the frequency responses of people and sensors. For a case-study with 10 people, the acoustic profiles, formed by all images acquired, are evaluated and compared in a mean square error sense. Finally, system performance, using False Match Rate (FMR)/False Non-Match Rate (FNMR) parameters and the Receiver Operating Characteristic (ROC) curve, is evaluated. On the basis of the obtained results, this system could be used for biometric applications. PMID:22163708

  10. Performance Evaluation of a Biometric System Based on Acoustic Images

    Directory of Open Access Journals (Sweden)

    Juan J. Villacorta

    2011-10-01

    Full Text Available An acoustic electronic scanning array for acquiring images from a person using a biometric application is developed. Based on pulse-echo techniques, multifrequency acoustic images are obtained for a set of positions of a person (front, front with arms outstretched, back and side. Two Uniform Linear Arrays (ULA with 15 l/2-equispaced sensors have been employed, using different spatial apertures in order to reduce sidelobe levels. Working frequencies have been designed on the basis of the main lobe width, the grating lobe levels and the frequency responses of people and sensors. For a case-study with 10 people, the acoustic profiles, formed by all images acquired, are evaluated and compared in a mean square error sense. Finally, system performance, using False Match Rate (FMR/False Non-Match Rate (FNMR parameters and the Receiver Operating Characteristic (ROC curve, is evaluated. On the basis of the obtained results, this system could be used for biometric applications.

  11. Associations between the Transsexual Voice Questionnaire (TVQMtF ) and self-report of voice femininity and acoustic voice measures.

    Science.gov (United States)

    Dacakis, Georgia; Oates, Jennifer; Douglas, Jacinta

    2017-11-01

    The Transsexual Voice Questionnaire (TVQ MtF ) was designed to capture the voice-related perceptions of individuals whose gender identity as female is the opposite of their birth-assigned gender (MtF women). Evaluation of the psychometric properties of the TVQ MtF is ongoing. To investigate associations between TVQ MtF scores and (1) self-perceptions of voice femininity and (2) acoustic parameters of voice pitch and voice quality in order to evaluate further the validity of the TVQ MtF . A strong correlation between TVQ MtF scores and self-ratings of voice femininity was predicted, but no association between TVQ MtF scores and acoustic measures of voice pitch and quality was proposed. Participants were 148 MtF women (mean age 48.14 years) recruited from the La Trobe Communication Clinic and the clinics of three doctors specializing in transgender health. All participants completed the TVQ MtF and 34 of these participants also provided a voice sample for acoustic analysis. Pearson product-moment correlation analysis was conducted to examine the associations between TVQ MtF scores and (1) self-perceptions of voice femininity and (2) acoustic measures of F0, jitter (%), shimmer (dB) and harmonic-to-noise ratio (HNR). Strong negative correlations between the participants' perceptions of their voice femininity and the TVQ MtF scores demonstrated that for this group of MtF women a low self-rating of voice femininity was associated with more frequent negative voice-related experiences. This association was strongest with the vocal-functioning component of the TVQ MtF . These strong correlations and high levels of shared variance between the TVQ MtF and a measure of a related construct provides evidence for the convergent validity of the TVQ MtF . The absence of significant correlations between the TVQ MtF and the acoustic data is consistent with the equivocal findings of earlier research. This finding indicates that these two measures assess different aspects of the voice

  12. Demonstration of acoustic source localization in air using single pixel compressive imaging

    Science.gov (United States)

    Rogers, Jeffrey S.; Rohde, Charles A.; Guild, Matthew D.; Naify, Christina J.; Martin, Theodore P.; Orris, Gregory J.

    2017-12-01

    Acoustic source localization often relies on large sensor arrays that can be electronically complex and have large data storage requirements to process element level data. Recently, the concept of a single-pixel-imager has garnered interest in the electromagnetics literature due to its ability to form high quality images with a single receiver paired with shaped aperture screens that allow for the collection of spatially orthogonal measurements. Here, we present a method for creating an acoustic analog to the single-pixel-imager found in electromagnetics for the purpose of source localization. Additionally, diffraction is considered to account for screen openings comparable to the acoustic wavelength. A diffraction model is presented and incorporated into the single pixel framework. In this paper, we explore the possibility of applying single pixel localization to acoustic measurements. The method is experimentally validated with laboratory measurements made in an air waveguide.

  13. Treatise on acoustics the first comprehensive English translation of E.F.F. Chladni's traité d’acoustique

    CERN Document Server

    Chladni, E F F

    2015-01-01

    This is the first comprehensive translation of the expanded French version of E.F.F. Chladni’s Traité d’Acoustique, using Chladni's 1802 Die Akustik for reference and clarification.  Chladni’s experiments and observations with sound and vibrations profoundly influenced the development of the field of Acoustics.  The famous Chladni diagrams along with other observations are contained in Die Akustik, published in German in 1802 and Traité d’Acoustique, a greatly expanded version, published in French in 1809.  The present translation was undertaken by Robert T. Beyer, PhD (1920-2008), noted acoustician, Professor of Physics at Brown University, and Gold Medal recipient of the Acoustical Society of America. Along with many other projects completed over the course of his career, Dr. Beyer translated Von Neumann’s seminal work, Mathematical Foundations of Quantum Mechanics from the original German, spent 30 years translating Russian physics treatises and journals, served as editor of the English t...

  14. Radiosynthesis of (S)-["1"8F]T1: The first PET radioligand for molecular imaging of α3β4 nicotinic acetylcholine receptors

    International Nuclear Information System (INIS)

    Sarasamkan, Jiradanai; Fischer, Steffen; Deuther-Conrad, Winnie; Ludwig, Friedrich-Alexander; Scheunemann, Matthias; Arunrungvichian, Kuntarat; Vajragupta, Opa; Brust, Peter

    2017-01-01

    Recent pharmacologic data revealed the implication of α3β4 nicotinic acetylcholine receptors (nAChRs) in nicotine and drug addiction. To image α3β4 nAChRs in vivo, we aimed to establish the synthesis of a ["1"8F]-labelled analog of the highly affine and selective α3β4 ligand (S)-3-(4-(4-fluorophenyl)-1H-1,2,3-triazol-1-yl)quinuclidine ((S)-T1). (S)-["1"8F]T1 was synthesized from ethynyl-4-["1"8F]fluorobenzene (["1"8F]5) and (S)-azidoquinuclidine by click reaction. After a synthesis time of 130 min (S)-["1"8F]T1 was obtained with a radiochemical yield (non-decay corrected) of 4.3±1.3%, a radiochemical purity of >99% and a molar activity of >158 GBq/μmol. The brain uptake and the brain-to-blood ratio of (S)-["1"8F]T1 in mice at 30 min post injection were 2.02 (SUV) and 6.1, respectively. According to an ex-vivo analysis, the tracer remained intact (>99%) in brain. Only one major radiometabolite was detected in plasma and urine samples. In-vitro autoradiography on pig brain slices revealed binding of (S)-["1"8F]T1 to brain regions associated with the expression of α3β4 nAChRs, which could be reduced by the α3β4 nAChR selective drug AT-1001. These findings make (S)-["1"8F]T1 a potential tool for the non-invasive imaging of α3β4 nAChRs in the brain by PET. - Highlights: • (S)-["1"8F]T1 is a promising α3ß4 nAChR ligand for PET imaging. • The novel radioligand (S)-["1"8F]T1 was synthesized by click reaction. • The potential of (S)-["1"8F]T1 was shown by in vitro autoradiography and in vivo evaluation in mice.

  15. Effect of scanner acoustic background noise on strict resting-state fMRI

    Directory of Open Access Journals (Sweden)

    C. Rondinoni

    2013-04-01

    Full Text Available Functional MRI (fMRI resting-state experiments are aimed at identifying brain networks that support basal brain function. Although most investigators consider a ‘resting-state' fMRI experiment with no specific external stimulation, subjects are unavoidably under heavy acoustic noise produced by the equipment. In the present study, we evaluated the influence of auditory input on the resting-state networks (RSNs. Twenty-two healthy subjects were scanned using two similar echo-planar imaging sequences in the same 3T MRI scanner: a default pulse sequence and a reduced “silent” pulse sequence. Experimental sessions consisted of two consecutive 7-min runs with noise conditions (default or silent counterbalanced across subjects. A self-organizing group independent component analysis was applied to fMRI data in order to recognize the RSNs. The insula, left middle frontal gyrus and right precentral and left inferior parietal lobules showed significant differences in the voxel-wise comparison between RSNs depending on noise condition. In the presence of low-level noise, these areas Granger-cause oscillations in RSNs with cognitive implications (dorsal attention and entorhinal, while during high noise acquisition, these connectivities are reduced or inverted. Applying low noise MR acquisitions in research may allow the detection of subtle differences of the RSNs, with implications in experimental planning for resting-state studies, data analysis, and ergonomic factors.

  16. Effect of scanner acoustic background noise on strict resting-state fMRI.

    Science.gov (United States)

    Rondinoni, C; Amaro, E; Cendes, F; dos Santos, A C; Salmon, C E G

    2013-04-01

    Functional MRI (fMRI) resting-state experiments are aimed at identifying brain networks that support basal brain function. Although most investigators consider a 'resting-state' fMRI experiment with no specific external stimulation, subjects are unavoidably under heavy acoustic noise produced by the equipment. In the present study, we evaluated the influence of auditory input on the resting-state networks (RSNs). Twenty-two healthy subjects were scanned using two similar echo-planar imaging sequences in the same 3T MRI scanner: a default pulse sequence and a reduced "silent" pulse sequence. Experimental sessions consisted of two consecutive 7-min runs with noise conditions (default or silent) counterbalanced across subjects. A self-organizing group independent component analysis was applied to fMRI data in order to recognize the RSNs. The insula, left middle frontal gyrus and right precentral and left inferior parietal lobules showed significant differences in the voxel-wise comparison between RSNs depending on noise condition. In the presence of low-level noise, these areas Granger-cause oscillations in RSNs with cognitive implications (dorsal attention and entorhinal), while during high noise acquisition, these connectivities are reduced or inverted. Applying low noise MR acquisitions in research may allow the detection of subtle differences of the RSNs, with implications in experimental planning for resting-state studies, data analysis, and ergonomic factors.

  17. Synthesis of 4-[18F]fluorophenyl triphenylphosphonium as a novel imaging agent for mitochondrial dysfunction

    International Nuclear Information System (INIS)

    Kim, Jung Young; Min, Jung Joon; Song, Ho Cheon; Bom, Hee Seung; Sanjiv, S. Gambhir

    2005-01-01

    It has been known for decades that lipophilic cations such as rhodamine-123 and tetraphenylphosphonium(TPP) salts can penetrate the plasma and mitochondrial membranes and selectively accumulate in mitochondria, because of the negative inner mitochondrial transmembrane potential. Therefore, the F-18 labeled TPP have a potential as a PET probe for in vivo molecular imaging of mitochondrial dysfunction and tumor. We prepared in this study the 4-[ 1 9F]Fluorophenyl triphenylphosphonium iodide standard for synthesis of 4-[ 18 F]Fluorophenyl triphenylphosphonium. The standard material 19 F-TPP was synthesized according to stirring the mixture of triphenylphosphine, 4-fluoro-iodobenzene and palladium catalyst in xylene. This residue was purified by HPLC using semi-preparative column (rt : 24.1 min) and evaluated by 1H-NMR, ESI-MS (357.1217). For the radiosynthesis of 18 F-TPP, NO2TPP derived from triphenylphosphine was first prepared as a precursor for 18 F-TPP. The anhydrous 18F-fluoride (10 mCi, from GE PETtrace) residue was added to NO 2 TPP (1 mg) in dry DMSO (0.32 ml). The reaction mixture was heated at 120 .deg. C for 15 min in oil bath. This solution was purified by HPLC (rt : 25.5 min). The product (0.7 mCi) was dried in a rotary evaporator and passed through a 0.22 mm membrane filter into a sterile vial. 18 FTPP was synthesized by nucleophilic substitution reaction of NO 2 TPP with [ 18 F]fluoride. The radiochemical purity of 18F-TPP determined by analytical HPLC (same gradient as used for semi-preparative HPLC, flow rate: 1.0 ml/min) was above 95%, and radiochemical yield for 18 F-TPP was 10-15% for 60 min of synthesis. The radiosynthesis of 18 FTPP in high radiochemical purity was achieved through a one-step reaction

  18. Acoustic Imaging Frequency Dynamics of Ferroelectric Domains by Atomic Force Microscopy

    International Nuclear Information System (INIS)

    Kun-Yu, Zhao; Hua-Rong, Zeng; Hong-Zhang, Song; Sen-Xing, Hui; Guo-Rong, Li; Qing-Rui, Yin; Shimamura, Kiyoshi; Kannan, Chinna Venkadasamy; Villora, Encarnacion Antonia Garcia; Takekawa, Shunji; Kitamura, Kenji

    2008-01-01

    We report the acoustic imaging frequency dynamics of ferroelectric domains by low-frequency acoustic probe microscopy based on the commercial atomic force microscopy It is found that ferroelectric domain could be firstly visualized at lower frequency down to 0.5 kHz by AFM-based acoustic microscopy The frequency-dependent acoustic signal revealed a strong acoustic response in the frequency range from 7kHz to 10kHz, and reached maximum at 8.1kHz. The acoustic contrast mechanism can be ascribed to the different elastic response of ferroelectric microstructures to local elastic stress fields, which is induced by the acoustic wave transmitting in the sample when the piezoelectric transducer is vibrating and exciting acoustic wave under ac electric fields due to normal piezoelectric effects. (condensed matter: electronic structure, electrical, magnetic, and optical properties)

  19. Radiosynthesis and biological evaluation of N-(2-[18F]fluoropropionyl)-3,4-dihydroxy-l-phenylalanine as a PET tracer for oncologic imaging.

    Science.gov (United States)

    Tang, Caihua; Nie, Dahong; Tang, Ganghua; Gao, Siyuan; Liu, Shaoyu; Wen, Fuhua; Tang, Xiaolan

    2017-07-01

    Several 11 C and 18 F labeled 3,4-dihydroxy-l-phenylalanine (l-DOPA) analogues have been used for neurologic and oncologic diseases, especially for brain tumors and neuroendocrine tumors PET imaging. However, 18 F-labeled N-substituted l-DOPA analogues have not been reported so far. In the current study, radiosynthesis and biological evaluation of a new 18 F-labeled l-DOPA analogue, N-(2-[ 18 F]fluoropropionyl)-3,4-dihydroxy-l-phenylalanine ([ 18 F]FPDOPA) for tumor PET imaging are performed. The synthesis of [ 18 F]FPDOPA was via a two-step reaction sequence from 4-nitrophenyl-2-[ 18 F]fluoropropionate ([ 18 F]NFP). The biodistribution of [ 18 F]FPDOPA was determined in normal Kunming mice. In vitro competitive inhibition and protein incorporation experiments were performed with SPC-A-1 lung adenocarcinoma cell lines. PET/CT studies of [ 18 F]FPDOPA were conducted in C6 rat glioma and SPC-A-1 human lung adenocarcinoma and H460 human large cell lung cancer-bearing nude mice. [ 18 F]FPDOPA was prepared with a decay-corrected radiochemical yield of 28±5% and a specific activity of 50±15GBq/μmol (n=10) within 125min. In vitro cell experiments showed that [ 18 F]FPDOPA uptake in SPC-A-1 cells was primarily transported through Na + -independent system L, with Na + -dependent system B 0,+ and system ASC partly involved in it. Biodistribution data in mice showed that renal-bladder route was the main excretory system of [ 18 F]FPDOPA. PET imaging demonstrated intense accumulation of [ 18 F]FPDOPA in several tumor xenografts, with (8.50±0.40)%ID/g in C6 glioma, (6.30±0.12)%ID/g in SPC-A-1 lung adenocarcinoma, and (6.50±0.10)%ID/g in H460 large cell lung cancer, respectively. A novel N-substituted 18 F-labeled L-DOPA analogue [ 18 F]FPDOPA is synthesized and evaluated in vitro and in vivo. The results support that [ 18 F]FPDOPA seems to be a potential PET tracer for tumor imaging, especially be a better potential PET tracer than [ 18 F]fluoro-2-deoxy-d-glucose ([ 18 F

  20. A combination of the acoustic radiosity and the image source method

    DEFF Research Database (Denmark)

    Koutsouris, Georgios I.; Brunskog, Jonas; Jeong, Cheol-Ho

    2012-01-01

    A combined model for room acoustic predictions is developed, aiming to treat both diffuse and specular reflections in a unified way. Two established methods are incorporated: acoustical radiosity, accounting for the diffuse part, and the image source method, accounting for the specular part...

  1. Heat Transfer Characteristics of a Focused Surface Acoustic Wave (F-SAW Device for Interfacial Droplet Jetting

    Directory of Open Access Journals (Sweden)

    Donghwi Lee

    2018-06-01

    Full Text Available In this study, we investigate the interfacial droplet jetting characteristics and thermal stability of a focused surface acoustic wave device (F-SAW. An F-SAW device capable of generating a 20 MHz surface acoustic wave by applying sufficient radio frequency power (2–19 W on a 128°-rotated YX-cut piezoelectric lithium niobate substrate for interfacial droplet jetting is proposed. The interfacial droplet jetting characteristics were visualized by a shadowgraph method using a high-speed camera, and a heat transfer experiment was conducted using K-type thermocouples. The interfacial droplet jetting characteristics (jet angle and height were analyzed for two different cases by applying a single interdigital transducer and two opposite interdigital transducers. Surface temperature variations were analyzed with radio frequency input power increases to evaluate the thermal stability of the F-SAW device in air and water environments. We demonstrate that the maximum temperature increase of the F-SAW device in the water was 1/20 of that in the air, owing to the very high convective heat transfer coefficient of the water, resulting in prevention of the performance degradation of the focused acoustic wave device.

  2. Multifunctional hydroxyapatite/Na(Y/Gd)F4:Yb3+,Er3+ composite fibers for drug delivery and dual modal imaging.

    Science.gov (United States)

    Liu, Min; Liu, Hui; Sun, Shufen; Li, Xuejiao; Zhou, Yanmin; Hou, Zhiyao; Lin, Jun

    2014-02-04

    Porous hydroxyapatite (HAp) composite fibers functionalized with up-conversion (UC) luminescent and magnetic Na(Y/Gd)F4:Yb(3+),Er(3+) nanocrystals (NCs) have been fabricated via electrospinning. After transferring hydrophobic oleic acid-capped Na(Y/Gd)F4:Yb(3+),Er(3+) NCs into aqueous solution, these water-dispersible NCs were dispersed into precursor electrospun solution containing CTAB. Na(Y/Gd)F4:Yb(3+),Er(3+)@HAp composite fibers were fabricated by the high temperature treatment of the electrospun Na(Y/Gd)F4:Yb(3+),Er(3+) NCs decorated precursor fibers. The biocompatibility test on MC 3T3-E1 cells using MTT assay shows that the HAp composite fibers have negligible cytotoxity, which reveals the HAp composite fibers could be a drug carrier for drug delivery. Because the contrast brightening is enhanced at increased concentrations of Gd(3+), the HAp composite fibers can serve as T1 magnetic resonance imaging contrast agents. In addition, the composites uptaken by MC 3T3-E1 cells present the UC luminescent emission of Er(3+) under the excitation of a 980 nm near-infrared laser. The above findings reveal Na(Y/Gd)F4:Yb(3+),Er(3+)@HAp composite fibers have potential applications in drug storage/release and magnetic resonance/UC luminescence imaging.

  3. Multi-crack imaging using nonclassical nonlinear acoustic method

    International Nuclear Information System (INIS)

    Zhang Lue; Zhang Ying; Liu Xiao-Zhou; Gong Xiu-Fen

    2014-01-01

    Solid materials with cracks exhibit the nonclassical nonlinear acoustical behavior. The micro-defects in solid materials can be detected by nonlinear elastic wave spectroscopy (NEWS) method with a time-reversal (TR) mirror. While defects lie in viscoelastic solid material with different distances from one another, the nonlinear and hysteretic stress—strain relation is established with Preisach—Mayergoyz (PM) model in crack zone. Pulse inversion (PI) and TR methods are used in numerical simulation and defect locations can be determined from images obtained by the maximum value. Since false-positive defects might appear and degrade the imaging when the defects are located quite closely, the maximum value imaging with a time window is introduced to analyze how defects affect each other and how the fake one occurs. Furthermore, NEWS-TR-NEWS method is put forward to improve NEWS-TR scheme, with another forward propagation (NEWS) added to the existing phases (NEWS and TR). In the added phase, scanner locations are determined by locations of all defects imaged in previous phases, so that whether an imaged defect is real can be deduced. NEWS-TR-NEWS method is proved to be effective to distinguish real defects from the false-positive ones. Moreover, it is also helpful to detect the crack that is weaker than others during imaging procedure. (electromagnetism, optics, acoustics, heat transfer, classical mechanics, and fluid dynamics)

  4. High-spatial-resolution sub-surface imaging using a laser-based acoustic microscopy technique.

    Science.gov (United States)

    Balogun, Oluwaseyi; Cole, Garrett D; Huber, Robert; Chinn, Diane; Murray, Todd W; Spicer, James B

    2011-01-01

    Scanning acoustic microscopy techniques operating at frequencies in the gigahertz range are suitable for the elastic characterization and interior imaging of solid media with micrometer-scale spatial resolution. Acoustic wave propagation at these frequencies is strongly limited by energy losses, particularly from attenuation in the coupling media used to transmit ultrasound to a specimen, leading to a decrease in the depth in a specimen that can be interrogated. In this work, a laser-based acoustic microscopy technique is presented that uses a pulsed laser source for the generation of broadband acoustic waves and an optical interferometer for detection. The use of a 900-ps microchip pulsed laser facilitates the generation of acoustic waves with frequencies extending up to 1 GHz which allows for the resolution of micrometer-scale features in a specimen. Furthermore, the combination of optical generation and detection approaches eliminates the use of an ultrasonic coupling medium, and allows for elastic characterization and interior imaging at penetration depths on the order of several hundred micrometers. Experimental results illustrating the use of the laser-based acoustic microscopy technique for imaging micrometer-scale subsurface geometrical features in a 70-μm-thick single-crystal silicon wafer with a (100) orientation are presented.

  5. Acoustical holographic recording with coherent optical read-out and image processing

    Science.gov (United States)

    Liu, H. K.

    1980-10-01

    New acoustic holographic wave memory devices have been designed for real-time in-situ recording applications. The basic operating principles of these devices and experimental results through the use of some of the prototypes of the devices are presented. Recording media used in the device include thermoplastic resin, Crisco vegetable oil, and Wilson corn oil. In addition, nonlinear coherent optical image processing techniques including equidensitometry, A-D conversion, and pseudo-color, all based on the new contact screen technique, are discussed with regard to the enhancement of the normally poor-resolved acoustical holographic images.

  6. Piezoelectric Shunt Vibration Damping of F-15 Panel under High Acoustic Excitation

    Science.gov (United States)

    Wu, Shu-Yau; Turner, Travis L.; Rizzi, Stephen A.

    2000-01-01

    At last year's SPIE symposium, we reported results of an experiment on structural vibration damping of an F-15 underbelly panel using piezoelectric shunting with five bonded PZT transducers. The panel vibration was induced with an acoustic speaker at an overall sound pressure level (OASPL) of about 90 dB. Amplitude reductions of 13.45 and 10.72 dB were achieved for the first and second modes, respectively, using single- and multiple-mode shunting. It is the purpose of this investigation to extend the passive piezoelectric shunt-damping technique to control structural vibration induced at higher acoustic excitation levels, and to examine the controllability and survivability of the bonded PZT transducers at these high levels. The shunting experiment was performed with the Thermal Acoustic Fatigue Apparatus (TAFA) at the NASA Langley Research Center using the same F-15 underbelly panel. The TAFA is a progressive wave tube facility. The panel was mounted in one wall of the TAFA test section using a specially designed mounting fixture such that the panel was subjected to grazing-incidence acoustic excitation. Five PZT transducers were used with two shunt circuits designed to control the first and second modes of the structure between 200 and 400 Hz. We first determined the values of the shunt inductance and resistance at an OASPL of 130 dB. These values were maintained while we gradually increased the OASPL from 130 to 154 dB in 6-dB steps. During each increment, the frequency response function between accelerometers on the panel and the acoustic excitation measured by microphones, before and after shunting, were recorded. Good response reduction was observed up to the 148dB level. The experiment was stopped at 154 dB due to wire breakage from vibration at a transducer wire joint. The PZT transducers, however, were still bonded well on the panel and survived at this high dB level. We also observed shifting of the frequency peaks toward lower frequency when the OASPL

  7. EPR experiments in LiTbF4, LiHoF4, and LiErF4 at submillimeter frequencies

    DEFF Research Database (Denmark)

    Magariño, J.; Tuchendler, J.; Beauvillain, P.

    1980-01-01

    Electron-paramagnetic-resonance experiments in LiTbF4, LiHoF4, and LiErF4 have been performed at frequencies between 70 and 600 GHz, in magnetic fields up to 60 kG and in the temperature range 1.4......Electron-paramagnetic-resonance experiments in LiTbF4, LiHoF4, and LiErF4 have been performed at frequencies between 70 and 600 GHz, in magnetic fields up to 60 kG and in the temperature range 1.4...

  8. A generalized strategy for designing (19)F/(1)H dual-frequency MRI coil for small animal imaging at 4.7 Tesla.

    Science.gov (United States)

    Hu, Lingzhi; Hockett, Frank D; Chen, Junjie; Zhang, Lei; Caruthers, Shelton D; Lanza, Gregory M; Wickline, Samuel A

    2011-07-01

    To propose and test a universal strategy for building (19) F/(1) H dual-frequency RF coil that permits multiple coil geometries. The feasibility to design (19) F/(1) H dual-frequency RF coil based on coupled resonator model was investigated. A series capacitive matching network enables robust impedance matching for both harmonic oscillating modes of the coupled resonator. Two typical designs of (19) F/(1) H volume coils (birdcage and saddle) at 4.7T were implemented and evaluated with electrical bench test and in vivo (19) F/(1) H dual-nuclei imaging. For various combinations of internal resistances of the sample coil and secondary resonator, numerical solutions for the tunable capacitors to optimize impedance matching were obtained using a root-seeking program. Identical and homogeneous B1 field distribution at (19) F and (1) H frequencies were observed in bench test and phantom image. Finally, in vivo mouse imaging confirmed the sensitivity and homogeneity of the (19) F/(1) H dual-frequency coil design. A generalized strategy for designing (19) F/(1) H dual-frequency coils based on the coupled resonator approach was developed and validated. A unique feature of this design is that it preserves the B1 field homogeneity of the RF coil at both resonant frequencies. Thus it minimizes the susceptibility effect on image co-registration. Copyright © 2011 Wiley-Liss, Inc.

  9. Acoustic imaging of vapor bubbles through optically non-transparent media

    International Nuclear Information System (INIS)

    Kolbe, W.F.; Turko, B.T.; Leskovar, B.

    1983-10-01

    A preliminary investigation of the feasibility of acoustic imaging of vapor bubbles through optically nontransparent media is described. Measurements are reported showing the echo signals produced by air filled glass spheres of various sizes positioned in an aqueous medium as well as signals produced by actual vapor bubbles within a water filled steel pipe. In addition, the influence of the metallic wall thickness and material on the amplitude of the echo signals is investigated. Finally several examples are given of the imaging of spherical bubbles within metallic pipes using a simulated array of acoustic transducers mounted circumferentially around the pipe. The measurement procedures and a description of the measuring system are also given

  10. Acoustic rhinometry (AR): An Alternative Method to Image Nasal Airway Geometry

    DEFF Research Database (Denmark)

    Straszek, Sune; Pedersen, O.F.

      ACOUSTIC RHINOMETRY (AR): AN ALTERNATIVE METHOD TO IMAGE NASAL AIRWAY GEOMETRY.  INTRODUCTION AND BACKGROUND:  In human studies the acoustic reflection technique was first applied to describe the area-distance relationship of the lower airways, but later the acoustic reflection technique appeared...... to be of more use in the description of nasal cavity geometry. Applied to human subjects AR has been applied to monitor the effect of corrective surgery and mucosal effects of pharmacological interventions. In recent years, however, AR has found use also in pharmacological studies in animals ranging in size...

  11. Extraction of Overt Verbal Response from the Acoustic Noise in a Functional Magnetic Resonance Imaging Scan by Use of Segmented Active Noise Cancellation

    Science.gov (United States)

    Jung, Kwan-Jin; Prasad, Parikshit; Qin, Yulin; Anderson, John R.

    2013-01-01

    A method to extract the subject's overt verbal response from the obscuring acoustic noise in an fMRI scan is developed by applying active noise cancellation with a conventional MRI microphone. Since the EPI scanning and its accompanying acoustic noise in fMRI are repetitive, the acoustic noise in one time segment was used as a reference noise in suppressing the acoustic noise in subsequent segments. However, the acoustic noise from the scanner was affected by the subject's movements, so the reference noise was adaptively adjusted as the scanner's acoustic properties varied in time. This method was successfully applied to a cognitive fMRI experiment with overt verbal responses. PMID:15723385

  12. (S)-4-(3-18F-fluoropropyl)-L-glutamic acid: an 18F-labeled tumor-specific probe for PET/CT imaging--dosimetry.

    Science.gov (United States)

    Smolarz, Kamilla; Krause, Bernd Joachim; Graner, Frank-Philipp; Wagner, Franziska Martina; Hultsch, Christina; Bacher-Stier, Claudia; Sparks, Richard B; Ramsay, Susan; Fels, Lüder M; Dinkelborg, Ludger M; Schwaiger, Markus

    2013-06-01

    The glutamic acid derivative (S)-4-(3-(18)F-Fluoropropyl)-l-glutamic acid ((18)F-FSPG, alias BAY 94-9392), a new PET tracer for the detection of malignant diseases, displayed promising results in non-small cell lung cancer patients. The aim of this study was to provide dosimetry estimates for (18)F-FSPG based on human whole-body PET/CT measurements. (18)F-FSPG was prepared by a fully automated 2-step procedure and purified by a solid-phase extraction method. PET/CT scans were obtained for 5 healthy volunteers (mean age, 59 y; age range, 51-64 y; 2 men, 3 women). Human subjects were imaged for up to 240 min using a PET/CT scanner after intravenous injection of 299 ± 22.5 MBq of (18)F-FSPG. Image quantification, time-activity data modeling, estimation of normalized number of disintegrations, and production of dosimetry estimates were performed using the RADAR (RAdiation Dose Assessment Resource) method for internal dosimetry and in general concordance with the methodology and principles as presented in the MIRD 16 document. Because of the renal excretion of the tracer, the absorbed dose was highest in the urinary bladder wall and kidneys, followed by the pancreas and uterus. The individual organ doses (mSv/MBq) were 0.40 ± 0.058 for the urinary bladder wall, 0.11 ± 0.011 for the kidneys, 0.077 ± 0.020 for the pancreas, and 0.030 ± 0.0034 for the uterus. The calculated effective dose was 0.032 ± 0.0034 mSv/MBq. Absorbed dose to the bladder and the effective dose can be reduced significantly by frequent bladder-voiding intervals. For a 0.75-h voiding interval, the bladder dose was reduced to 0.10 ± 0.012 mSv/MBq, and the effective dose was reduced to 0.015 ± 0.0010 mSv/MBq. On the basis of the distribution and biokinetic data, the determined radiation dose for (18)F-FSPG was calculated to be 9.5 ± 1.0 mSv at a patient dose of 300 MBq, which is of similar magnitude to that of (18)F-FDG (5.7 mSv). The effective dose can be reduced to 4.5 ± 0.30 mSv (at 300 MBq

  13. Acoustic imaging of underground storage tank wastes: A feasibility study. Final report

    International Nuclear Information System (INIS)

    Turpening, R.; Zhu, Z.; Caravana, C.; Matarese, J.

    1995-01-01

    The objectives for this underground storage tank (UST) imaging investigation are: (1) to assess the feasibility of using acoustic methods in UST wastes, if shown to be feasible, develop and assess imaging strategies; (2) to assess the validity of using chemical simulants for the development of acoustic methods and equipment. This investigation examined the velocity of surrogates, both salt cake and sludge surrogates. In addition collected seismic cross well data in a real tank (114-TX) on the Hanford Reservation. Lastly, drawing on the knowledge of the simulants and the estimates of the velocities of the waste in tank 114-TX the authors generated a hypothetical model of waste in a tank and showed that non-linear travel time tomographic imaging would faithfully image that stratigraphy

  14. Nicotinic α4β2 receptor imaging agents. Part III. Synthesis and biological evaluation of 3-(2-(S)-azetidinylmethoxy)-5-(3′-18F-fluoropropyl)pyridine (18F-nifzetidine)

    International Nuclear Information System (INIS)

    Pichika, Rama; Easwaramoorthy, Balu; Christian, Bradley T.; Shi, Bingzhi; Narayanan, Tanjore K.; Collins, Daphne; Mukherjee, Jogeshwar

    2011-01-01

    Thalamic and extrathalamic nicotinic α4β2 receptors found in the brain have been implicated in Alzheimer's disease, Parkinson's disease, substance abuse and other disorders. We report here the development of 3-(2-(S)-azetidinylmethoxy)-5-(3′-fluoropropyl)pyridine (nifzetidine) as a new putative high-affinity antagonist for nicotinic α4β2 receptors. Nifzetidine in rat brain homogenate assays containing α4β2 sites labeled with 3 H-cytisine exhibited a binding affinity: Ki=0.67 nM. The fluorine-18 analog, 3-(2-(S)-azetidinylmethoxy)-5-(3′- 18 F-fluoropropyl)pyridine ( 18 F-nifzetidine), was synthesized in 20%–40% yield, and apparent specific activity was estimated to be above 2 Ci/μmol. Rat brain slices indicated selective binding of 18 F-nifzetidine to thalamus, subiculum, striata, cortex and other regions consistent with α4β2 receptor distribution. This selective binding was displaced >85% by 150 μM nicotine. Positron emission tomography (PET) imaging studies of 18 F-nifzetidine in anesthetized rhesus monkey showed slow uptake in the various brain regions. Retention of 18 F-nifzetidine was maximal in the thalamus and lateral geniculate followed by regions of the temporal and frontal cortex. Cerebellum showed the least uptake. Thalamus to cerebellum ratio was about 2.3 at 180 min postinjection and continued to rise. 18 F-Nifzetidine shows promise as a new PET imaging agent for α4β2 nAChR. However, the slow kinetics suggests a need for >3-h PET scans for quantitative studies of the α4β2 nAChRs.

  15. 28th International Acoustical Imaging Symposium

    CERN Document Server

    André, Michael P; Andre, Michael; Arnold, Walter; Bamber, Jeff; Burov, Valentin; Chubachi, Noriyoshi; Erikson, Kenneth; Ermert, Helmut; Fink, Mathias; Gan, Woon S; Granz, Bernd; Greenleaf, James; Hu, Jiankai; Jones, Joie P; Khuri-Yakub, Pierre; Laugier, Pascal; Lee, Hua; Lees, Sidney; Levin, Vadim M; Maev, Roman; Masotti, Leonardo; Nowicki, Andrzej; O’Brien, William; Prasad, Manika; Rafter, Patrick; Rouseff, Daniel; Thijssen, Johan; Tittmann, Bernard; Tortoli, Piero; Steen, Anton; Waag, Robert; Wells, Peter; Acoustical Imaging

    2007-01-01

    The International Acoustical Imaging Symposium has been held continuously since 1968 as a unique forum for advanced research, promoting the sharing of technology, developments, methods and theory among all areas of acoustics. The interdisciplinary nature of the Symposium and the wide international participation are two of its main strengths. Scientists from around the world present their papers in an informal environment conducive to lively discussion and cross-fertilization. The fact that a loyal community of scientists has supported this Series since 1968 is evidence of its impact on the field. The Symposium Series continues to thrive in a busy calendar of scientific meetings without the infrastructure of a professional society. It does so because those who attend and those who rely on the Proceedings as a well-known reference work acknowledge its value. This Volume 28 of the Proceedings likewise contains an excellent collection of papers presented in six major categories, offering both a broad perspective ...

  16. Whole-body biodistribution and dosimetry estimates of a novel radiotracer for imaging of serotonin 4 receptors in brain: [18F]MNI-698

    International Nuclear Information System (INIS)

    Tavares, Adriana Alexandre S.; Caillé, Fabien; Barret, Olivier; Papin, Caroline; Lee, Hsiaoju; Morley, Thomas J.; Fowles, Krista; Holden, Daniel; Seibyl, John P.; Alagille, David; Tamagnan, Gilles D.

    2014-01-01

    Introduction: A new radiotracer for imaging the serotonin 4 receptors (5-HT 4 ) in brain, [ 18 F]MNI-698, was recently developed by our group. Evaluation in nonhuman primates indicates the novel radiotracer holds promise as an imaging agent of 5-HT 4 in brain. This paper aims to describe the whole-body biodistribution and dosimetry estimates of [ 18 F]MNI-698. Methods: Whole-body positron emission tomography (PET) images were acquired over 240 minutes after intravenous bolus injection of [ 18 F]MNI-698 in adult rhesus monkeys. Different models were investigated for quantification of radiation absorbed and effective doses using OLINDA/EXM 1.0 software. Results: The radiotracer main elimination route was found to be urinary and the critical organ was the urinary bladder. Modeling of the urinary bladder voiding interval had a considerable effect on the estimated effective dose. Normalization of rhesus monkeys’ organs and whole-body masses to human equivalent reduced the calculated dosimetry values. The effective dose ranged between 0.017 and 0.027 mSv/MBq. Conclusion: The dosimetry estimates, obtained when normalizing organ and whole-body weights and applying the urinary bladder model, indicate that the radiation doses from [ 18 F]MNI-698 comply with limits and guidelines recommended by key regulatory authorities that govern the translation of radiotracers to human clinical trials. The timing of urinary bladder emptying should be considered when designing future clinical protocols with [ 18 F]MNI-698, in order to minimize the subject absorbed doses

  17. Chirped or time modulated excitation compared to short pulses for photoacoustic imaging in acoustic attenuating media

    Science.gov (United States)

    Burgholzer, P.; Motz, C.; Lang, O.; Berer, T.; Huemer, M.

    2018-02-01

    In photoacoustic imaging, optically generated acoustic waves transport the information about embedded structures to the sample surface. Usually, short laser pulses are used for the acoustic excitation. Acoustic attenuation increases for higher frequencies, which reduces the bandwidth and limits the spatial resolution. One could think of more efficient waveforms than single short pulses, such as pseudo noise codes, chirped, or harmonic excitation, which could enable a higher information-transfer from the samples interior to its surface by acoustic waves. We used a linear state space model to discretize the wave equation, such as the Stoke's equation, but this method could be used for any other linear wave equation. Linear estimators and a non-linear function inversion were applied to the measured surface data, for onedimensional image reconstruction. The proposed estimation method allows optimizing the temporal modulation of the excitation laser such that the accuracy and spatial resolution of the reconstructed image is maximized. We have restricted ourselves to one-dimensional models, as for higher dimensions the one-dimensional reconstruction, which corresponds to the acoustic wave without attenuation, can be used as input for any ultrasound imaging method, such as back-projection or time-reversal method.

  18. Model simulations of line-of-sight effects in airglow imaging of acoustic and fast gravity waves from ground and space

    Science.gov (United States)

    Aguilar Guerrero, J.; Snively, J. B.

    2017-12-01

    Acoustic waves (AWs) have been predicted to be detectable by imaging systems for the OH airglow layer [Snively, GRL, 40, 2013], and have been identified in spectrometer data [Pilger et al., JASP, 104, 2013]. AWs are weak in the mesopause region, but can attain large amplitudes in the F region [Garcia et al., GRL, 40, 2013] and have local impacts on the thermosphere and ionosphere. Similarly, fast GWs, with phase speeds over 100 m/s, may propagate to the thermosphere and impart significant local body forcing [Vadas and Fritts, JASTP, 66, 2004]. Both have been clearly identified in ionospheric total electron content (TEC), such as following the 2013 Moore, OK, EF5 tornado [Nishioka et al., GRL, 40, 2013] and following the 2011 Tohoku-Oki tsunami [e.g., Galvan et al., RS, 47, 2012, and references therein], but AWs have yet to be unambiguously imaged in MLT data and fast GWs have low amplitudes near the threshold of detection; nevertheless, recent imaging systems have sufficient spatial and temporal resolution and sensitivity to detect both AWs and fast GWs with short periods [e.g., Pautet et al., AO, 53, 2014]. The associated detectability challenges are related to the transient nature of their signatures and to systematic challenges due to line-of-sight (LOS) effects such as enhancements and cancelations due to integration along aligned or oblique wavefronts and geometric intensity enhancements. We employ a simulated airglow imager framework that incorporates 2D and 3D emission rate data and performs the necessary LOS integrations for synthetic imaging from ground- and space-based platforms to assess relative intensity and temperature perturbations. We simulate acoustic and fast gravity wave perturbations to the hydroxyl layer from a nonlinear, compressible model [e.g., Snively, 2013] for different idealized and realistic test cases. The results show clear signal enhancements when acoustic waves are imaged off-zenith or off-nadir and the temporal evolution of these

  19. Reference values for acoustic rhinometry in children from 4 to 13 years

    DEFF Research Database (Denmark)

    Straszek, Sune; Moeller, Alexander; Hall, Graham L

    2008-01-01

    a reference range for nasal volumes and minimum cross-sectional areas (MCA) in healthy non-decongested children aged 4 to 13 years. Methods: 256 primary school children (mean 7.95 years, range 3.8 - 13.1 ys, 123m/133f) were measured by acoustic rhinometry. Variables were MCA (first, second and absolute......: In multiple linear regression models height was the main predictor for all AR variables although weight was also a significant predictor of MCA's. There was no association between any AR variables with sex, atopy or hayfever but children with current wheeze (within last 12 months) and asthma had decreased...

  20. Radiochemical synthesis of 3-(4-[18F] Fluorophenyl)-8-hydroxy-1, 2, 3, 4-tetrahydrochromeno [3, 4-c] pyridin-5-one: A putative dopamine D$4 receptor PET imaging agent

    International Nuclear Information System (INIS)

    Li, G.C.; Yin, D.Z.; Wang, M.W.; Cheng, D.F.; Wang, Y.X.

    2005-01-01

    Introduction: The dopamine D 4 receptor has lately received increasing interest since it has been hypothesized to be involved in the pathology and pharmacotherapy of schizophrenia. While this receptor is expressed in lower density in various extrastriatal brain regions and its distribution is still unclear due to the lack of suitable imaging agent and its level change in schizophrenia is controversial. Herein, based on the structure-activity analysis of chromeno[3, 4-c]pyridine- 5-ones as potential dopamine D 4 receptor ligands, a putative D 4 subtype positron emission tomography (PET) radioligand, 3-(4-[ 18 F]fluorophenyl)-8-hydroxy-1, 2, 3, 4-tetrahydrochromeno [3, 4-c]pyridin-5-one ([ 18 F]FHTP), was designed and synthesized. Methods: The radiochemical synthesis route was shown in Figure 1. [ 18 F]Fluoride was produced with a Cyclone-30 (IBA, Belgium) by 18 O(p, n) 18 F reaction using enriched 18 O-H 2 O and eluted from a Dowex 1-X8 anion-exchange column with aqueous potassium carbonate (20 mg/mL). 4-[ 18 F]Fluorobenzaldehyde was prepared according to the method reported by Alan A. Wilson and et al.. Then, 8-hydroxy-1, 2, 3, 4-tetrahydrochromeno [3, 4-c]pyridin-5-one, sodium cyanoborohydride, methanol and acetic acid were added to the dry residue, The mixture was then sealed and heated at 120 degree C for 12 min. At the end of the reaction, the mixture was cooled, diluted with ethyl acetate and washed with water. The extracted organic layer was passed through a small anhydrous magnesium sulfate column. After removal of the solvents in the mixture at 50 degree C under a stream of nitrogen, the obtained residue was redissolved in methanol and purified with a semi-preparative HPLC system, then the desired product was collected. Results: The radiochemical synthesis of [ 18 F]FHTP took around 110 min at EOS with an overall radiochemical yield 19% (decay-corrected) and its radiochemical purity was higher than 95%. Conclusion: A presumed dopamine D 4 receptor PET

  1. Identifying Vulnerable Plaques with Acoustic Radiation Force Impulse Imaging

    Science.gov (United States)

    Doherty, Joshua Ryan

    The rupture of arterial plaques is the most common cause of ischemic complications including stroke, the fourth leading cause of death and number one cause of long term disability in the United States. Unfortunately, because conventional diagnostic tools fail to identify plaques that confer the highest risk, often a disabling stroke and/or sudden death is the first sign of disease. A diagnostic method capable of characterizing plaque vulnerability would likely enhance the predictive ability and ultimately the treatment of stroke before the onset of clinical events. This dissertation evaluates the hypothesis that Acoustic Radiation Force Impulse (ARFI) imaging can noninvasively identify lipid regions, that have been shown to increase a plaque's propensity to rupture, within carotid artery plaques in vivo. The work detailed herein describes development efforts and results from simulations and experiments that were performed to evaluate this hypothesis. To first demonstrate feasibility and evaluate potential safety concerns, finite- element method simulations are used to model the response of carotid artery plaques to an acoustic radiation force excitation. Lipid pool visualization is shown to vary as a function of lipid pool geometry and stiffness. A comparison of the resulting Von Mises stresses indicates that stresses induced by an ARFI excitation are three orders of magnitude lower than those induced by blood pressure. This thesis also presents the development of a novel pulse inversion harmonic tracking method to reduce clutter-imposed errors in ultrasound-based tissue displacement estimates. This method is validated in phantoms and was found to reduce bias and jitter displacement errors for a marked improvement in image quality in vivo. Lastly, this dissertation presents results from a preliminary in vivo study that compares ARFI imaging derived plaque stiffness with spatially registered composition determined by a Magnetic Resonance Imaging (MRI) gold standard

  2. The results of borehole acoustic imaging from a granite in the Jihlava District, Czech Republic: implications for structural geological research

    Czech Academy of Sciences Publication Activity Database

    Nováková, Lucie; Novák, P.; Brož, Milan; Sosna, K.; Pitrák, K.; Kasíková, J.; Rukavičková, L.; Maňák, L.

    2012-01-01

    Roč. 4, č. 4 (2012), s. 92-101 ISSN 1916-9779 R&D Projects: GA MPO(CZ) FR-TI1/367 Institutional research plan: CEZ:AV0Z30460519 Keywords : acoustic borehole imaging * structural geology * paleostress analysis Subject RIV: DC - Siesmology, Volcanology, Earth Structure

  3. Repeatability of hypoxia PET imaging using [{sup 18}F]HX4 in lung and head and neck cancer patients: a prospective multicenter trial

    Energy Technology Data Exchange (ETDEWEB)

    Zegers, Catharina M.L.; Elmpt, Wouter van; Lambin, Philippe [Maastricht University Medical Centre, Department of Radiation Oncology (MAASTRO), GROW - School for Oncology and Developmental Biology, Maastricht (Netherlands); Szardenings, Katrin [Threshold Pharmaceuticals, South San Francisco, CA (United States); Kolb, Hartmuth; Chien, David [Siemens Medical Solutions USA, Inc., Siemens Molecular Imaging Biomarker Research, Culver City, CA (United States); Waxman, Alan [Cedars-Sinai Medical Center, Los Angeles, CA (United States); Subramaniam, Rathan M. [Boston University School of Medicine, Boston, MA (United States); Johns Hopkins Medical Institutions, Division of Nuclear Medicine, Russell H Morgan Department of Radiology and Radiologic Sciences, Baltimore, MD (United States); Moon, Dae Hyuk [University of Ulsan College of Medicine, Department of Nuclear Medicine, Asan Medical Center, Seoul (Korea, Republic of); Brunetti, Jacqueline C. [Holy Name Medical Center, Teaneck, NJ (United States); Srinivas, Shyam M. [Cleveland Clinic, Department of Nuclear Medicine, Imaging Institute, Cleveland, OH (United States)

    2015-11-15

    Hypoxia is an important factor influencing tumor progression and treatment efficacy. The aim of this study was to investigate the repeatability of hypoxia PET imaging with [{sup 18}F]HX4 in patients with head and neck and lung cancer. Nine patients with lung cancer and ten with head and neck cancer were included in the analysis (NCT01075399). Two sequential pretreatment [{sup 18}F]HX4 PET/CT scans were acquired within 1 week. The maximal and mean standardized uptake values (SUV{sub max} and SUV{sub mean}) were defined and the tumor-to-background ratios (TBR) were calculated. In addition, hypoxic volumes were determined as the volume of the tumor with a TBR >1.2 (HV{sub 1.2}). Bland Altman analysis of the uptake parameters was performed and coefficients of repeatability were calculated. To evaluate the spatial repeatability of the uptake, the PET/CT images were registered and a voxel-wise comparison of the uptake was performed, providing a correlation coefficient. All parameters of [{sup 18}F]HX4 uptake were significantly correlated between scans: SUV{sub max} (r = 0.958, p < 0.001), SUV{sub mean} (r = 0.946, p < 0.001), TBR{sub max} (r = 0.962, p < 0.001) and HV{sub 1.2} (r = 0.995, p < 0.001). The relative coefficients of repeatability were 15 % (SUV{sub mean}), 17 % (SUV{sub max}) and 17 % (TBR{sub max}). Voxel-wise analysis of the spatial uptake pattern within the tumors provided an average correlation of 0.65 ± 0.14. Repeated hypoxia PET scans with [{sup 18}F]HX4 provide reproducible and spatially stable results in patients with head and neck cancer and patients with lung cancer. [{sup 18}F]HX4 PET imaging can be used to assess the hypoxic status of tumors and has the potential to aid hypoxia-targeted treatments. (orig.)

  4. Radiosynthesis and preclinical evaluation of [{sup 18}F] 4-(2-fluoroethoxy)-2H-chromen-2-one as a novel myocardial perfusion imaging agent

    Energy Technology Data Exchange (ETDEWEB)

    Bhusari, Arun M.; Degani, Mariam S. [Institute of Chemical Technology, Mumbai (India). Dept. of Pharmaceutical Sciences and Technology; Lakshminarayanan, N.; Pawar, Yogita P.; Moghe, Surendra H.; Rajan, M.G.R. [Bhabha Atomic Research Centre, Mumbai (India). Radiation Medicine Center

    2017-07-01

    Recently we developed [{sup 18}F] 4-(2-fluoroethoxy)-2H-chromen-2-one as a novel {sup 18}F myocardial perfusion imaging radiotracer. It was synthesized in good radiochemical yield (>90%). The total time from radiosynthesis to its purification was less than 40 min, with excellent radiochemical purity (≥99%). It showed good stability over a period of 5 h at room temperature. The partition coefficient (log P) of radiotracer was found to be 2.70, suggesting the lipophilic nature of radiotracer. Ex vivo biodistribution study of radiotracer in normal Wistar rats for 30 min post-injection, demonstrated a good heart uptake (>1.3% ID/g) and favorable pharmacokinetics. Additionally, the radiotracer showed significant excretion (>11% ID) by liver, which is indicative of its rapid clearance. Further, in vivo biodistribution study of radiotracer in New Zealand White rabbit provided the clear PET/CT images of cardiomyocytes and myocardial perfusion. All these experimental findings suggest that [{sup 18}F] 4-(2-fluoroethoxy)-2H-chromen-2-one could be used as a potential hit for myocardial perfusion imaging.

  5. Clinical studies of 18F-FDG and 18F-FP-β-CIT PET imaging in hemi-Parkinson's disease

    International Nuclear Information System (INIS)

    Zhao Jun; Lin Xiangtong; Guan Yihui; Zuo Chuantao; Zhang Zhengwei; Wang Jian; Sun Bomin; Chen Zhengping

    2003-01-01

    Objective: To study the characteristics of 18 F-fluorodeoxyglucose (FDG) and 18 F-N-3-fluoro-propyl-2β-carbomethoxy-3β-(4-iodophenyl) nortropane ( 18 F-FP-β-CIT) PET imaging in patients with hemi-Parkinson's disease (hemi-PD) and to assess their value in early diagnosis. Methods: 34 cases of hemi-PD (Hoehn and Yahr stage I-II) and 16 normal control subjects were selected for this study. 16 patients were performed with 18 F-FDG PET imaging, 18 patients with 18 F-FP-β-CIF, while 6 patients of them both 18 F-FDG and 18 F-FP-β-CIT. 30 min after injection of 185-259 MBq 18 F-FDG, 3D brain scans were acquired. Region of interest (ROI) analysis and statistical parametric mapping (SPM) were applied. 18 F-FP-β-CIT PET imaging was carried out 2-3 h post injection, and (ROI-cerebellum)/cerebellum ratio was calculated. Results: In right hemi-PD, reductions in 18 F-FDG metabolism were observed in the left basal ganglia compared with control group, but with no significant difference (P>0.05). The results of SPM analysis showed that a significant reduction in FDG uptake in the left superior frontal gyrus, middle frontal gyrus, inferior frontal gyrus and left middle temporal gyrus, whereas a significant increase in the bilateral precentral gyrus , superior parietal lobule, left middle occipital gyrus and left thalamus as compared with the control group. There was a significant reduction in 18 F-FP-β-CIT uptake in putamen, its reduction was found not only in the contralateral putamen, but also in the ipsilateral ones, and more pronounced in the contralateral posterior putamen. Conclusions: 18 F-FDG PET imaging is non-specific for the early diagnosis of PD. 18 F-FP-β-CIT PET imaging could find the changes of striatum dopamine transporter at early stage, therefore it was helpful for early diagnosis and differential diagnosis of PD. Combined with 18 F-FDG PET imaging, the changes of local cerebral glucose metabolism in PD could also be evaluated

  6. Evaluation of tumour hypoxia during radiotherapy using [{sup 18}F]HX4 PET imaging and blood biomarkers in patients with head and neck cancer

    Energy Technology Data Exchange (ETDEWEB)

    Zegers, Catharina M.L.; Hoebers, Frank J.P.; Elmpt, Wouter van; Oellers, Michel C.; Eekers, Danielle; Balmaekers, Leo; Arts-Pechtold, Marlies; Lambin, Philippe [Maastricht University Medical Centre, Department of Radiation Oncology (MAASTRO), GROW - School for Oncology and Developmental Biology, Maastricht (Netherlands); Bons, Judith A. [Maastricht University Medical Centre, Central Diagnostic Laboratory, Maastricht (Netherlands); Troost, Esther G.C. [Maastricht University Medical Centre, Department of Radiation Oncology (MAASTRO), GROW - School for Oncology and Developmental Biology, Maastricht (Netherlands); Helmholtz Zentrum Dresden-Rossendorf, Dresden (Germany); Technische Universitaet Dresden, OncoRay, Department of Radiation Oncology, Medical Faculty and University Hospital Carl Gustav Carus, Dresden (Germany); Mottaghy, Felix M. [Maastricht University Medical Centre, Department of Nuclear Medicine, Maastricht (Netherlands); RWTH Aachen University, University Hospital, Department of Nuclear Medicine, Aachen (Germany)

    2016-11-15

    Increased tumour hypoxia is associated with a worse overall survival in patients with head and neck squamous cell carcinoma (HNSCC). The aims of this study were to evaluate treatment-associated changes in [{sup 18}F]HX4-PET, hypoxia-related blood biomarkers, and their interdependence. [{sup 18}F]HX4-PET/CT scans of 20 patients with HNSCC were acquired at baseline and after ±20 Gy of radiotherapy. Within the gross-tumour-volumes (GTV; primary and lymph nodes), mean and maximum standardized uptake values, the hypoxic fraction (HF) and volume (HV) were calculated. Also, the changes in spatial uptake pattern were evaluated using [{sup 18}F]HX4-PET/CT imaging. For all patients, the plasma concentration of CAIX, osteopontin and VEGF was assessed. At baseline, tumour hypoxia was detected in 69 % (22/32) of the GTVs. During therapy, we observed a significant decrease in all image parameters. The HF decreased from 21.7 ± 19.8 % (baseline) to 3.6 ± 10.0 % (during treatment; P < 0.001). Only two patients had a HV > 1 cm{sup 3} during treatment, which was located for >98 % within the baseline HV. During treatment, no significant changes in plasma CAIX or VEGF were observed, while osteopontin was increased. [{sup 18}F]HX4-PET/CT imaging allows monitoring changes in hypoxia during (chemo)radiotherapy whereas the blood biomarkers were not able to detect a treatment-associated decrease in hypoxia. (orig.)

  7. 18F-FAC PET selectively images hepatic infiltrating CD4 and CD8 T cells in a mouse model of autoimmune hepatitis.

    Science.gov (United States)

    Salas, Jessica R; Chen, Bao Ying; Wong, Alicia; Cheng, Donghui; Van Arnam, John S; Witte, Owen N; Clark, Peter M

    2018-04-26

    Immune cell-mediated attack on the liver is a defining feature of autoimmune hepatitis and hepatic allograft rejection. Despite an assortment of diagnostic tools, invasive biopsies remain the only method for identifying immune cells in the liver. We evaluated whether PET imaging with radiotracers that quantify immune activation ( 18 F-FDG and 18 F-FAC) and hepatocyte biology ( 18 F-DFA) can visualize and quantify hepatic infiltrating immune cells and hepatocyte inflammation, respectively, in a preclinical model of autoimmune hepatitis. Methods: Mice treated with Concanavalin A (ConA) to induce a model of autoimmune hepatitis or vehicle were imaged with 18 F-FDG, 18 F-FAC, and 18 F-DFA PET. Immunohistochemistry, digital autoradiography, and ex vivo accumulation assays were used to localize areas of altered radiotracer accumulation in the liver. For comparison, mice treated with an adenovirus to induce a viral hepatitis or vehicle were imaged with 18 F-FDG, 18 F-FAC, and 18 F-DFA PET. 18 F-FAC PET was performed on mice treated with ConA, and vehicle or dexamethasone. Biopsy samples of patients suffering from autoimmune hepatitis were immunostained for deoxycytidine kinase (dCK). Results: Hepatic accumulation of 18 F-FDG and 18 F-FAC was 173% and 61% higher, respectively, and hepatic accumulation of 18 F-DFA was 41% lower in a mouse model of autoimmune hepatitis compared to control mice. Increased hepatic 18 F-FDG accumulation was localized to infiltrating leukocytes and inflamed sinusoidal endothelial cells, increased hepatic 18 F-FAC accumulation was concentrated in infiltrating CD4 and CD8 cells, and decreased hepatic 18 F-DFA accumulation was apparent in hepatocytes throughout the liver. In contrast, viral hepatitis increased hepatic 18 F-FDG accumulation by 109% and decreased hepatic 18 F-DFA accumulation by 20% but had no effect on hepatic 18 F-FAC accumulation (non-significant 2% decrease). 18 F-FAC PET provided a non-invasive biomarker of the efficacy of

  8. Syntheses of 2-nitroimidazole derivatives conjugated with 1,4,7-triazacyclononane-N,N'-diacetic acid labeled with F-18 using an aluminum complex method for hypoxia imaging.

    Science.gov (United States)

    Hoigebazar, Lathika; Jeong, Jae Min; Lee, Ji-Youn; Shetty, Dinesh; Yang, Bo Yeun; Lee, Yun-Sang; Lee, Dong Soo; Chung, June-Key; Lee, Myung Chul

    2012-04-12

    Hypoxia imaging is important for diagnosis of ischemic diseases, and thus various (18)F-labeled radiopharmaceuticals have been developed. However, (18)F-labeling requires multistep procedures including azeotropic distillation, which is complicated and difficult to automate. Recently, (18)F-labeling method using Al-F complex in aqueous solution was devised that offered a straightforward (18)F-labeling procedure. We synthesized nitroimidazole derivatives conjugated with 1,4,7-triazacyclononane-1,4-diacetic acid (NODA) that can be labeled with (18)F using Al-F complex and examined their radiochemistries, in vitro and in vivo biological properties, and animal PET imaging characteristics. We found that the synthesized derivatives have excellent (18)F-labeling efficiencies, high stabilities, specific uptakes in cultured hypoxic tumor cells, and high tumor to nontumor ratios in xenografted mice. Furthermore, the derivatives were labeled with (18)F in a straightforward manner within 15 min at high labeling efficiencies and radiochemical purities. In conclusion, (18)F-labeled NODA-nitroimidazole conjugates were developed and proved to be promising hypoxia PET agents. © 2012 American Chemical Society

  9. Ion conductivities of ZrF4-BaF2-CsF glasses

    International Nuclear Information System (INIS)

    Kawamoto, Yoji; Nohara, Ichiro

    1987-01-01

    The glass-forming region in the ZrF 4 -BaF 2 -CsF glass system has been determined and the ac conductivity and the transport number of fluoride ions have been measured. The conductivities of compounds β-Cs 2 ZrF 6 , α-SrZrF 6 , α-BaZrF 6 , β-BaZrF 6 and α-PbZrF 6 have also been measured. These results and a previous study of ZrF 4 -BaF 2 -MF n (M: the groups I-IV metals) glasses revealed the following: (1) the ZrF 4 -BaF 2 -CsF glasses are exclusively fluoride-ion conductors; (2) the ionic conductivities of ZrF 4 -based glasses are predominantly determined by the activation energies for conduction; (3) the activation energy for conduction decreases with an increase in the average polarizability of glass-constituting cations; (4) a decrease in average Zr-F bond length and a lowering of the average F coordination number of Zr are presumed to increase the activation energy for conduction. Principles of developing ZrF 4 -based glasses with higher conductivities have also been proposed. (Auth.)

  10. Imaging of heart acoustic based on the sub-space methods using a microphone array.

    Science.gov (United States)

    Moghaddasi, Hanie; Almasganj, Farshad; Zoroufian, Arezoo

    2017-07-01

    Heart disease is one of the leading causes of death around the world. Phonocardiogram (PCG) is an important bio-signal which represents the acoustic activity of heart, typically without any spatiotemporal information of the involved acoustic sources. The aim of this study is to analyze the PCG by employing a microphone array by which the heart internal sound sources could be localized, too. In this paper, it is intended to propose a modality by which the locations of the active sources in the heart could also be investigated, during a cardiac cycle. In this way, a microphone array with six microphones is employed as the recording set up to be put on the human chest. In the following, the Group Delay MUSIC algorithm which is a sub-space based localization method is used to estimate the location of the heart sources in different phases of the PCG. We achieved to 0.14cm mean error for the sources of first heart sound (S 1 ) simulator and 0.21cm mean error for the sources of second heart sound (S 2 ) simulator with Group Delay MUSIC algorithm. The acoustical diagrams created for human subjects show distinct patterns in various phases of the cardiac cycles such as the first and second heart sounds. Moreover, the evaluated source locations for the heart valves are matched with the ones that are obtained via the 4-dimensional (4D) echocardiography applied, to a real human case. Imaging of heart acoustic map presents a new outlook to indicate the acoustic properties of cardiovascular system and disorders of valves and thereby, in the future, could be used as a new diagnostic tool. Copyright © 2017. Published by Elsevier B.V.

  11. The 4s- and 4p- XPS spectra of Xe, XeF2 and XeF4

    International Nuclear Information System (INIS)

    Ohno, Masahide

    2003-01-01

    The 4s- and 4p- XPS spectra of Xe gas, XeF 2 molecule and XeF 4 molecule are calculated by an ab-initio atomic many-body theory. The 4s-peak and the prominent '4p'-peak are predicted well by the present theory. In XeF 2 and XeF 4 the spectral lines observed below the 4d-double ionization threshold are the 4d -2 4f multiplet states strongly perturbed by the interaction with the initial 4p 1/2 -hole state. They are very similar to the spectral lines which emerge with an increase in atomic number (e.g. Ba)

  12. Application of acoustical holography for construction shadow images in ultrasonic testing

    International Nuclear Information System (INIS)

    Kutzner, J.; Zimpfer, J.

    1977-01-01

    The full-scale, three-dimensional presentation of material defects by means of acoustical holography is limited on the one hand by an insufficient resolving power in depth of the procedure and, on the other hand, by the fact that the defects of the material to be examined often reflect mirror-like. Examined is the possible range of reducing these limitations by means of constructing shadow images of defects in ultrasonic testing without - as it is usually done - reconstructing the sonic field reflected by the flow but reconstructing the sonic field diffracted at the flow by means of acoustical holography. It has been shown that acoustical holography, during which the amplitude information is always analyzed as well as - on principle - the phase information, improves the efficiency of ultrasonic testing to a large extent. (orig.) [de

  13. (18)F-nanobody for PET imaging of HER2 overexpressing tumors.

    Science.gov (United States)

    Xavier, Catarina; Blykers, Anneleen; Vaneycken, Ilse; D'Huyvetter, Matthias; Heemskerk, Jan; Lahoutte, Tony; Devoogdt, Nick; Caveliers, Vicky

    2016-04-01

    Radiolabeled nanobodies are exciting new probes for molecular imaging due to high affinity, high specificity and fast washout from the blood. Here we present the labeling of an anti-HER2 nanobody with (18)F and its validation for in vivo assessment of HER2 overexpression. The GMP grade anti-HER2 nanobody was labeled with the prosthetic group, N-succinimidyl-4-[(18)F]fluorobenzoate ([(18)F]-SFB), and its biodistribution, tumor targeting and specificity were evaluated in mouse and rat tumor models. [(18)F]FB-anti-HER2 nanobody was prepared with a 5-15% global yield (decay corrected) and a specific activity of 24.7 ± 8.2 MBq/nmol. In vivo studies demonstrated a high specific uptake for HER2 positive xenografts (5.94 ± 1.17 and 3.74 ± 0.52%IA/g, 1 and 3h p.i.) with high tumor-to-blood and tumor-to-muscle ratios generating high contrast PET imaging. The probe presented fast clearance through the kidneys (4%IA/g at 3h p.i.). [(18)F]FB-anti-HER2 nanobody is able to image HER2 expressing tumors when co-administered with the anti-HER2 therapeutic antibody trastuzumab (Herceptin), indicating the possibility of using the tracer in patients undergoing Herceptin therapy. The GMP grade anti-HER2 nanobody was labeled with (18)F. This new PET probe for imaging HER2 overexpression in tumors has ample potential for clinical translation. Copyright © 2016 Elsevier Inc. All rights reserved.

  14. 18F-nanobody for PET imaging of HER2 overexpressing tumors

    International Nuclear Information System (INIS)

    Xavier, Catarina; Blykers, Anneleen; Vaneycken, Ilse; D'Huyvetter, Matthias; Heemskerk, Jan; Lahoutte, Tony; Devoogdt, Nick; Caveliers, Vicky

    2016-01-01

    Introduction: Radiolabeled nanobodies are exciting new probes for molecular imaging due to high affinity, high specificity and fast washout from the blood. Here we present the labeling of an anti-HER2 nanobody with 18 F and its validation for in vivo assessment of HER2 overexpression. Methods: The GMP grade anti-HER2 nanobody was labeled with the prosthetic group, N-succinimidyl-4-[ 18 F]fluorobenzoate ([ 18 F]-SFB), and its biodistribution, tumor targeting and specificity were evaluated in mouse and rat tumor models. Results: [ 18 F]FB-anti-HER2 nanobody was prepared with a 5–15% global yield (decay corrected) and a specific activity of 24.7 ± 8.2 MBq/nmol. In vivo studies demonstrated a high specific uptake for HER2 positive xenografts (5.94 ± 1.17 and 3.74 ± 0.52%IA/g, 1 and 3 h p.i.) with high tumor-to-blood and tumor-to-muscle ratios generating high contrast PET imaging. The probe presented fast clearance through the kidneys (4%IA/g at 3 h p.i.). [ 18 F]FB-anti-HER2 nanobody is able to image HER2 expressing tumors when co-administered with the anti-HER2 therapeutic antibody trastuzumab (Herceptin), indicating the possibility of using the tracer in patients undergoing Herceptin therapy. Conclusions: The GMP grade anti-HER2 nanobody was labeled with 18 F. This new PET probe for imaging HER2 overexpression in tumors has ample potential for clinical translation.

  15. SU-F-I-14: 3D Breast Digital Phantom for XACT Imaging

    Energy Technology Data Exchange (ETDEWEB)

    Tang, S; Laaroussi, R; Chen, J; Samant, P; Xiang, L [University of Oklahoma, Norman, OK (United States); Chen, Y; Ahmad, S [University of Oklahoma Health Sciences Center, Oklahoma City, OK (United States); Yang, K [Massachusetts General Hospital, Boston, MA (United States)

    2016-06-15

    Purpose: The X-ray induced acoustic computed tomography (XACT) is a new imaging modality which combines X-ray contrast and high ultrasonic resolution in a single modality. Using XACT in breast imaging, a 3D breast volume can be imaged by only one pulsed X-ray radiation, which could dramatically reduce the imaging dose for patients undergoing breast cancer screening and diagnosis. A 3D digital phantom that contains both X-ray properties and acoustic properties of different tissue types is indeed needed for developing and optimizing the XACT system. The purpose of this study is to offer a realistic breast digital phantom as a valuable tool for improving breast XACT imaging techniques and potentially leading to better diagnostic outcomes. Methods: A series of breast CT images along the coronal plane from a patient who has breast calcifications are used as the source images. A HU value based segmentation algorithm is employed to identify breast tissues in five categories, namely the skin tissue, fat tissue, glandular tissue, chest bone and calcifications. For each pixel, the dose related parameters, such as material components and density, and acoustic related parameters, such as frequency-dependent acoustic attenuation coefficient and bandwidth, are assigned based on tissue types. Meanwhile, other parameters which are used in sound propagation, including the sound speed, thermal expansion coefficient, and heat capacity are also assigned to each tissue. Results: A series of 2D tissue type image is acquired first and the 3D digital breast phantom is obtained by using commercial 3D reconstruction software. When giving specific settings including dose depositions and ultrasound center frequency, the X-ray induced initial pressure rise can be calculated accordingly. Conclusion: The proposed 3D breast digital phantom represents a realistic breast anatomic structure and provides a valuable tool for developing and evaluating the system performance for XACT.

  16. of Nd3+ions in YLiF4 and LuLiF4 crystals

    Directory of Open Access Journals (Sweden)

    André Felipe Henriques Librantz

    2006-01-01

    Full Text Available Nd3+ ultraviolet (UV fluorescence induced by multiphotonic laser excitations was studied in doped Nd:YLiF4 (YLF and Nd:LuLiF4 (LLF crystals by using the time resolved spectroscopy technique. The UV luminescences are due to transitions between the 4f25d and the 4f3 electronic configurations of Nd3+ ions. The 4f25d configuration can be reached by direct pumping or by multiphotonic excitation, both processes give rise to the UV band emission with structure due to the strong phonon coupling expected for 5d orbital involvement in the transition. The multiphotonic excitation process is due to three photons (532 nanometers [nm] sequential absorptions by metastable levels of the 4f3 configuration split by crystalline local field. The sequential excitation of Nd by the laser excitation is attributed to the 4I9/2 + 532 nm t 4G7/2 ground state absorption followed by the 4G7/2 + 532 nm t 2F5/2 and 2F5/2 + 532 nm t 4f25d excited state absorptions. The UV emissions due to 4f25d configuration are parity allowed, having lifetime of 35 nanoseconds (ns in contrast to UV emissions from 4f3 configuration which are induced by two absorption steps and are parity forbidden showing longer lifetime of 8 microseconds (ms and narrow lines. The polarization effects of the UV emissions were studied and their behaviors are dependent on the excited state configuration involving or not involving the 5d orbital. The allowed UV emission positions were affected by the host variation more than the ones originated from the 4f3 configuration as expected. The electronic energy of the 4f25d configuration shifts to lower energy for increasing the crystal field.

  17. Differentiation of F4 receptor profiles in pigs based on their mucin 4 polymorphism, responsiveness to oral F4 immunization and in vitro binding of F4 to villi.

    Science.gov (United States)

    Nguyen, V U; Goetstouwers, T; Coddens, A; Van Poucke, M; Peelman, L; Deforce, D; Melkebeek, V; Cox, E

    2013-03-15

    F4(+) enterotoxigenic Escherichia coli (F4(+) ETEC) are an important cause of diarrhoea and mortality in piglets. F4(+) ETEC use their F4 fimbriae to adhere to specific receptors (F4Rs) on small intestinal brush borders, resulting in colonization of the small intestine. To prevent pigs from post-weaning diarrhoea, pigs should be vaccinated during the suckling period. Previously, we demonstrated that F4acR(+), but not F4acR(-) piglets could be orally immunized with purified F4 fimbriae resulting in a protective immunity against F4(+) ETEC infections, indicating that this immune response was F4R dependent. Recently, aminopeptidase N has been identified as a glycoprotein receptor important for this oral immune response. However, in some oral immunization experiments, a few F4acR(+) piglets did not show an antibody response upon oral immunization, suggesting additional receptors. Therefore, the binding profile of F4 to brush border membrane (glyco)proteins was determined for pigs differing in F4-specific antibody response upon oral immunization, in in vitro adhesion of F4(+)E. coli to small intestinal villi, and in Muc4 genotype. Six groups of pigs could be identified. Only two groups positive in all three assays showed two high molecular weight (MW) glycoprotein bands (>250kDa) suggesting that these high MW bands are linked to the MUC4 susceptible genotype. The fact that these bands were absent in the MUC4 resistant group which showed a positive immune response against F4 and was positive in the adhesion test confirm that at least one or perhaps more other F4Rs exist. Interestingly, two pigs that were positive in the villous adhesion assay did not show an immune response against F4 fimbriae. This suggests that a third receptor category might exist which allows the bacteria to adhere but does not allow effective immunization with soluble F4 fimbriae. Future research will be necessary to confirm or reveal the identity of these receptors. Copyright © 2012 Elsevier B

  18. 4-D imaging of seepage in earthen embankments with time-lapse inversion of self-potential data constrained by acoustic emissions localization

    Science.gov (United States)

    Rittgers, J. B.; Revil, A.; Planes, T.; Mooney, M. A.; Koelewijn, A. R.

    2015-02-01

    New methods are required to combine the information contained in the passive electrical and seismic signals to detect, localize and monitor hydromechanical disturbances in porous media. We propose a field experiment showing how passive seismic and electrical data can be combined together to detect a preferential flow path associated with internal erosion in a Earth dam. Continuous passive seismic and electrical (self-potential) monitoring data were recorded during a 7-d full-scale levee (earthen embankment) failure test, conducted in Booneschans, Netherlands in 2012. Spatially coherent acoustic emissions events and the development of a self-potential anomaly, associated with induced concentrated seepage and internal erosion phenomena, were identified and imaged near the downstream toe of the embankment, in an area that subsequently developed a series of concentrated water flows and sand boils, and where liquefaction of the embankment toe eventually developed. We present a new 4-D grid-search algorithm for acoustic emissions localization in both time and space, and the application of the localization results to add spatially varying constraints to time-lapse 3-D modelling of self-potential data in the terms of source current localization. Seismic signal localization results are utilized to build a set of time-invariant yet spatially varying model weights used for the inversion of the self-potential data. Results from the combination of these two passive techniques show results that are more consistent in terms of focused ground water flow with respect to visual observation on the embankment. This approach to geophysical monitoring of earthen embankments provides an improved approach for early detection and imaging of the development of embankment defects associated with concentrated seepage and internal erosion phenomena. The same approach can be used to detect various types of hydromechanical disturbances at larger scales.

  19. Acoustic anisotropy of acoustooptic TI(3)AsS(4) crystals.

    Science.gov (United States)

    Martynyuk-Lototska, Iryna; Kushnirevych, Marian; Zapeka, Bohdan; Krupych, Oleh; Kokhan, Oleksandr; Pogodin, Artem; Peresh, Eugen; Mys, Oksana; Vlokh, Rostyslav

    2015-02-20

    We present comprehensive experimental measurements and analysis of anisotropy of the acoustic wave velocities for TI(3)AsS(4) crystals, including the obliquity and nonorthogonality of the acoustic waves, and the deviations from purely longitudinal and transverse polarization types. We have found that the crystals under analysis are characterized by rather low transverse wave velocities v(23) and v(32), which are both equal to 630 m/s. It is shown that the efficiency of acoustooptic (AO) interactions in TI(3)AsS(4) can be notably increased when providing anisotropic interaction with the slowest transverse acoustic wave. Under the previously mentioned conditions, the AO figure-of-merit can be estimated to be extremely high, i.e., approximately 3×10(-12) s(3)/kg.

  20. Quantitative PET Imaging of Tissue Factor Expression Using 18F-Labeled Active Site-Inhibited Factor VII.

    Science.gov (United States)

    Nielsen, Carsten H; Erlandsson, Maria; Jeppesen, Troels E; Jensen, Mette M; Kristensen, Lotte K; Madsen, Jacob; Petersen, Lars C; Kjaer, Andreas

    2016-01-01

    Tissue factor (TF) is upregulated in many solid tumors, and its expression is linked to tumor angiogenesis, invasion, metastasis, and prognosis. A noninvasive assessment of tumor TF expression status is therefore of obvious clinical relevance. Factor VII is the natural ligand to TF. Here we report the development of a new PET tracer for specific imaging of TF using an (18)F-labeled derivative of factor VII. Active site-inhibited factor VIIa (FVIIai) was obtained by inactivation with phenylalanine-phenylalanine-arginine-chloromethyl ketone. FVIIai was radiolabeled with N-succinimidyl 4-(18)F-fluorobenzoate and purified. The corresponding product, (18)F-FVIIai, was injected into nude mice with subcutaneous human pancreatic xenograft tumors (BxPC-3) and investigated using small-animal PET/CT imaging 1, 2, and 4 h after injection. Ex vivo biodistribution was performed after the last imaging session, and tumor tissue was preserved for molecular analysis. A blocking experiment was performed in a second set of mice. The expression pattern of TF in the tumors was visualized by immunohistochemistry and the amount of TF in tumor homogenates was measured by enzyme-linked immunosorbent assay and correlated with the uptake of (18)F-FVIIai in the tumors measured in vivo by PET imaging. The PET images showed high uptake of (18)F-FVIIai in the tumor regions, with a mean uptake of 2.5 ± 0.3 percentage injected dose per gram (%ID/g) (mean ± SEM) 4 h after injection of 7.3-9.3 MBq of (18)F-FVIIai and with an average maximum uptake in the tumors of 7.1 ± 0.7 %ID/g at 4 h. In comparison, the muscle uptake was 0.2 ± 0.01 %ID/g at 4 h. At 4 h, the tumors had the highest uptake of any organ. Blocking with FVIIai significantly reduced the uptake of (18)F-FVIIai from 2.9 ± 0.1 to 1.4 ± 0.1 %ID/g (P < 0.001). The uptake of (18)F-FVIIai measured in vivo by PET imaging correlated (r = 0.72, P < 0.02) with TF protein level measured ex vivo. (18)F-FVIIai is a promising PET tracer for

  1. An Optimal Image-Based Method for Identification of Acoustic Emission (AE) Sources in Plate-Like Structures Using a Lead Zirconium Titanate (PZT) Sensor Array

    Science.gov (United States)

    Zhou, Li

    2018-01-01

    This paper proposes an innovative method for identifying the locations of multiple simultaneous acoustic emission (AE) events in plate-like structures from the view of image processing. By using a linear lead zirconium titanate (PZT) sensor array to record the AE wave signals, a reverse-time frequency-wavenumber (f-k) migration is employed to produce images displaying the locations of AE sources by back-propagating the AE waves. Lamb wave theory is included in the f-k migration to consider the dispersive property of the AE waves. Since the exact occurrence time of the AE events is usually unknown when recording the AE wave signals, a heuristic artificial bee colony (ABC) algorithm combined with an optimal criterion using minimum Shannon entropy is used to find the image with the identified AE source locations and occurrence time that mostly approximate the actual ones. Experimental studies on an aluminum plate with AE events simulated by PZT actuators are performed to validate the applicability and effectiveness of the proposed optimal image-based AE source identification method. PMID:29466310

  2. An Optimal Image-Based Method for Identification of Acoustic Emission (AE) Sources in Plate-Like Structures Using a Lead Zirconium Titanate (PZT) Sensor Array.

    Science.gov (United States)

    Yan, Gang; Zhou, Li

    2018-02-21

    This paper proposes an innovative method for identifying the locations of multiple simultaneous acoustic emission (AE) events in plate-like structures from the view of image processing. By using a linear lead zirconium titanate (PZT) sensor array to record the AE wave signals, a reverse-time frequency-wavenumber (f-k) migration is employed to produce images displaying the locations of AE sources by back-propagating the AE waves. Lamb wave theory is included in the f-k migration to consider the dispersive property of the AE waves. Since the exact occurrence time of the AE events is usually unknown when recording the AE wave signals, a heuristic artificial bee colony (ABC) algorithm combined with an optimal criterion using minimum Shannon entropy is used to find the image with the identified AE source locations and occurrence time that mostly approximate the actual ones. Experimental studies on an aluminum plate with AE events simulated by PZT actuators are performed to validate the applicability and effectiveness of the proposed optimal image-based AE source identification method.

  3. Declarative Intonation in Korean: AN Acoustical Study of F(o) Declination.

    Science.gov (United States)

    Ko, Do-Heung

    This dissertation investigates some acoustic features of declarative intonation in standard Korean based on the hypothesis that fundamental frequency (F_0 ) declination can be syntactically determined. In the course of this study, the following major issues are addressed: (i) What is the relation between sentence length and F_0 contours? (ii) Is there any difference in F_0 patterns between male and female speakers? (iii) Is F_0 declination exclusively a surface structure phenomenon? (iv) Are F_0 contours of parentheticals independent from those of the main clause? (v) What is the effect of word order on variations in F_0 ?. Ten subjects (seven male and three female speakers of the Seoul dialect) read sentences with various types of syntactic structure. In order to analyze F _0 declination phenomena, a software program, DoReMi, and an Impulse Audio Digitizer were used with a Macintosh computer. After obtaining the results from the computer, the Visi-Pitch was also used to confirm some F_0 traces. Major results from this research may be summarized as follows: (i) The rate of declination is not affected by the length of the syntactic unit. Particularly, initial and final values are nearly constant in both progressively longer simplex sentences and expanded embedded sentences. (ii) F_0 contours for male and female subjects are strikingly similar except for the different ranges. (iii) The deletion site plays a certain role in the process of F_0 contours, suggesting that declination may be determined at an underlying or abstract level. (iv) As in English, a parenthetical phrase or clause in Korean has a separate F_0 pattern in its own right, and the parenthetical does not perturb the F_0 pattern of the main clause. (v) Sentences with word orders which are used most frequently in discourse have shown the standard pattern of F_0 declination while orders which are used less frequently have unpredictable F _0 patterns in general.

  4. Synthesis of a dopamine transporter imaging agent, N-(3-[18F]fluoropropyl)-2β-carbomethoxy-3β-(4-iodophenyl)nortropane

    International Nuclear Information System (INIS)

    Choi, Yearn Seong; Oh, Seung Jun; Kim, Sang Eun; Choi, Yong; Lee, Kyung Han; Kim, Byung Tae; Chi, Dae Yoon

    1999-01-01

    N-(3-[ 18 F]fluoropropyl)-2β-carbomethoxy-3β-(4-iodophenyl)nortropane ([ 18 F]FP-CIT) has been shown to be very useful for imaging the dopamine transporter. However, synthesis of this radiotracer is somewhat troublesome. In this study, we used a new method for the preparation of ([ 18 F]FP-CIT) to increse radiochemical yield and effective specific activity. ([ 18 F]FP-CIT) was prepared by N-alkylation of nor β-CIT (2 mg) with 3-bromo-1 ([ 18 F]fluoropropane in the presence of Et 3 N (5-6 drops of DMF/CH 3 CN, 140 .deg. C, 20 min). 3-Bromo-1-[ 18 F]fluropropane was synthesized from 5 μL of 3-bromo-1-trifluoromethanesulfonyloxypropane (3-bromopropyl-1-triflate) and nBu 4 N 18 F at 80 .deg. C.The final compound was purified by reverse phase HPLC and formulated in 13% ethanol in saline. 3-Bromo-1-[ 18 F]fluoropropane was obtained from 3-bromopropyl-1-triflate and nBu 4 N 18 F in 77-80% yield. N-Alkylation of nor β-CIT with 3-bromo-1-[ 18 F]fluoropropane was carried out at 140 .deg. C using acetonitrile containing a small volume of DMF as the solvents. The overall yield of [ 18 F]FP-CIT was 5-10% (decay-corrected ) with a radiochemical purity higher than 99% and effective specific activity higher than the one reported in the literature based on their HPLC data. The final [ 18 F]FP-CIT solution had the optimal pH (7.0) and it was pyrogen-free. In this study, 3-bromopropyl-1-triflate was used as the precursor for the [ 18 F]fluorination reaction and new conditions were developed for purification of [ 18 F]FP-CIT by HPLC. We established this new method for the preparation of [ 18 F]FP-CIT, which gave high effective specific activity and relatively good yield.

  5. Neodymium-doped Sr5(PO4)3F and Sr5(VO4)3F

    International Nuclear Information System (INIS)

    Corker, D.L.; Nicholls, J.; Loutts, G.B.

    1995-01-01

    Neodymium-doped Sr 5 (PO 4 ) 3 F [neodymium strontium fluoride phosphate, (Nd,Sr) 5 (PO 4 ) 3 F] and neodymium-doped Sr 5 (VO 4 ) 3 F [neodymium strontium fluoride vanadate, (Nd,Sr) 5 (VO 4 ) 3 F] crystallize in space group P6 3 /m and are isostructural with calcium fluorophosphate, Ca 5 (PO 4 ) 3 F. There are two different Sr sites in Sr 5 (XO 4 ) 3 F, denoted Sr(1) and Sr(2). Using single-crystal X-ray diffraction the two structures were refined to R factors of 2.3 and 2.2%, respectively, showing that Nd is present at both Sr sites in (Sr,Nd) 5 (VO 4 ) 3 F but only at the Sr(2) site in (Sr,Nd) 5 (PO 4 ) 3 F. (orig.)

  6. Performance of a C4F8O gas radiator ring imaging Cherenkov detector using multi-anode photomultiplier tubes

    International Nuclear Information System (INIS)

    Artuso, M.; Boulahouache, C.; Blusk, S.; Butt, J.; Dorjkhaidav, O.; Menaa, N.; Mountain, R.; Muramatsu, H.; Nandakumar, R.; Randrianarivony, K.; Sia, R.; Skwarnicki, T.; Stone, S.; Wang, J.C.; Zhang, K.

    2006-01-01

    We report on tests of a novel ring imaging Cherenkov (RICH) detection system consisting of a 3-m-long gaseous C 4 F 8 O radiator, a focusing mirror, and a photon detector array based on Hamamatsu multi-anode photomultiplier tubes. This system was developed to identify charged particles in the momentum range from 3 to 70GeV/c for the BTeV experiment

  7. HULU SUNGAI PERAK BED SEDIMENT MAPPING USING UNDERWATER ACOUSTIC SONAR

    Directory of Open Access Journals (Sweden)

    N. Arriafdi

    2016-09-01

    Full Text Available Development in acoustic survey techniques in particular side scan sonar have revolutionized the way we are able to image, map and understand the riverbed environment. It is now cost effective to image large areas of the riverbed using these techniques and the backscatter image created from surveys provides base line data from which thematic maps of the riverbed environment including maps of morphological geology, can be derived when interpreted in conjunction with in situ sampling data. This article focuses on investigation characteristics of sediments and correlation of side scan backscatter image with signal strength. The interpretation of acoustic backscatter rely on experienced interpretation by eye of grey scale images produced from the data. A 990F Starfish Side Scan Sonar was used to collect and develop a series of sonar images along 6 km of Hulu Sungai Perak. Background sediments could be delineated accurately and the image textures could be linked to the actual river floor appearance through grab sampling. A major difference was found in the acoustic returns from the two research area studies: the upstream area shows much rougher textures. This is due to an actual differences in riverbed roughness, caused by a difference in bottom currents and sediment dynamics in the two areas. The highest backscatter correlates with coarsest and roughness sediment. Result suggest that image based backscatter classification shows considerable promise for interpretation of side scan sonar data for the production of geological maps.

  8. 18F-Labelled metomidate analogues as adrenocortical imaging agents

    International Nuclear Information System (INIS)

    Erlandsson, Maria; Karimi, Farhad; Lindhe, Orjan; Langstroem, Bengt

    2009-01-01

    Introduction: Two- and one-step syntheses of 18 F-labelled analogues of metomidate, such as 2-[ 18 F]fluoroethyl 1-[(1R)-1-phenylethyl]-1H-imidazole-5-carboxylate (1), 2-[ 18 F]fluoroethyl 1-[(1R)-1-(4-chlorophenyl)ethyl]-1H-imidazole-5-carboxylate (2), 2-[ 18 F]fluoroethyl 1-[(1R)-1-(4-bromophenyl)ethyl]-1H-imidazole-5-carboxylate (3), 3-[ 18 F]fluoropropyl 1-[(1R)-1-(4-bromophenyl)ethyl]-1H-imidazole-5-carboxylate (4) and 3-[ 18 F]fluoropropyl 1-[(1R)-1-phenylethyl]-1H-imidazole-5-carboxylate (5) are presented. Methods: Analogues 1-5 were prepared by a two-step reaction sequence that started with the synthesis of either 2-[ 18 F]fluoroethyl 4-methylbenzenesulfonate or 3-[ 18 F]fluoropropyl 4-methylbenzenesulfonate. These were used as 18 F-alkylating agents in the second step, in which they reacted with the ammonium salt of a 1-[(1R)-1-phenylethyl]-1H-imidazole-5-carboxylic acid. One-step-labelling syntheses of 1, 2 and 5 were also explored. Analogues 1-4 were biologically validated by frozen-section autoradiography and organ distribution. Metabolite analysis was performed for 2 and 3. Results: The radiochemical yield of the two-step synthesis was in the range of 10-29% and that of the one-step synthesis was 25-37%. Using microwave irradiation in the one-step synthesis of 1 and 2 increased the radiochemical yield to 46±3% and 79±30%, respectively. Conclusion: Both the frozen-section autoradiography and organ distribution results indicated that analogue 2 has a potential as an adrenocortical imaging agent, having the highest degree of specific adrenal binding and best ratio of adrenal to organ uptake among the compounds studied.

  9. Piezoelectric Zinc Oxide Based MEMS Acoustic Sensor

    Directory of Open Access Journals (Sweden)

    Aarti Arora

    2008-04-01

    Full Text Available An acoustic sensors exhibiting good sensitivity was fabricated using MEMS technology having piezoelectric zinc oxide as a dielectric between two plates of capacitor. Thin film zinc oxide has structural, piezoelectric and optical properties for surface acoustic wave (SAW and bulk acoustic wave (BAW devices. Oxygen effficient films are transparent and insulating having wide applications for sensors and transducers. A rf sputtered piezoelectric ZnO layer transforms the mechanical deflection of a thin etched silicon diaphragm into a piezoelectric charge. For 25-micron thin diaphragm Si was etched in tetramethylammonium hydroxide solution using bulk micromachining. This was followed by deposition of sandwiched structure composed of bottom aluminum electrode, sputtered 3 micron ZnO film and top aluminum electrode. A glass having 1 mm diameter hole was bonded on backside of device to compensate sound pressure in side the cavity. The measured value of central capacitance and dissipation factor of the fabricated MEMS acoustic sensor was found to be 82.4pF and 0.115 respectively, where as the value of ~176 pF was obtained for the rim capacitance with a dissipation factor of 0.138. The response of the acoustic sensors was reproducible for the devices prepared under similar processing conditions under different batches. The acoustic sensor was found to be working from 30Hz to 8KHz with a sensitivity of 139µV/Pa under varying acoustic pressure.

  10. TH-302 in Combination with Radiotherapy Enhances the Therapeutic Outcome and Is Associated with Pretreatment [18F]HX4 Hypoxia PET Imaging.

    Science.gov (United States)

    Peeters, Sarah G J A; Zegers, Catharina M L; Biemans, Rianne; Lieuwes, Natasja G; van Stiphout, Ruud G P M; Yaromina, Ala; Sun, Jessica D; Hart, Charles P; Windhorst, Albert D; van Elmpt, Wouter; Dubois, Ludwig J; Lambin, Philippe

    2015-07-01

    Conventional anticancer treatments are often impaired by the presence of hypoxia. TH-302 selectively targets hypoxic tumor regions, where it is converted into a cytotoxic agent. This study assessed the efficacy of the combination treatment of TH-302 and radiotherapy in two preclinical tumor models. The effect of oxygen modification on the combination treatment was evaluated and the effect of TH-302 on the hypoxic fraction (HF) was monitored using [(18)F]HX4-PET imaging and pimonidazole IHC stainings. Rhabdomyosarcoma R1 and H460 NSCLC tumor-bearing animals were treated with TH-302 and radiotherapy (8 Gy, single dose). The tumor oxygenation status was altered by exposing animals to carbogen (95% oxygen) and nicotinamide, 21% or 7% oxygen breathing during the course of the treatment. Tumor growth and treatment toxicity were monitored until the tumor reached four times its start volume (T4×SV). Both tumor models showed a growth delay after TH-302 treatment, which further increased when combined with radiotherapy (enhancement ratio rhabdomyosarcoma 1.23; H460 1.49). TH-302 decreases the HF in both models, consistent with its hypoxia-targeting mechanism of action. Treatment efficacy was dependent on tumor oxygenation; increasing the tumor oxygen status abolished the effect of TH-302, whereas enhancing the HF enlarged TH-302's therapeutic effect. An association was observed in rhabdomyosarcoma tumors between the pretreatment HF as measured by [(18)F]HX4-PET imaging and the T4×SV. The combination of TH-302 and radiotherapy is promising and warrants clinical testing, preferably guided by the companion biomarker [(18)F]HX4 hypoxia PET imaging for patient selection. ©2015 American Association for Cancer Research.

  11. Exploratory clinical trial of (4S)-4-(3-[18F]fluoropropyl)-L-glutamate for imaging xC- transporter using positron emission tomography in patients with non-small cell lung or breast cancer.

    Science.gov (United States)

    Baek, Sora; Choi, Chang-Min; Ahn, Sei Hyun; Lee, Jong Won; Gong, Gyungyub; Ryu, Jin-Sook; Oh, Seung Jun; Bacher-Stier, Claudia; Fels, Lüder; Koglin, Norman; Hultsch, Christina; Schatz, Christoph A; Dinkelborg, Ludger M; Mittra, Erik S; Gambhir, Sanjiv S; Moon, Dae Hyuk

    2012-10-01

    (4S)-4-(3-[(18)F]fluoropropyl)-l-glutamate (BAY 94-9392, alias [(18)F]FSPG) is a new tracer to image x(C)(-) transporter activity with positron emission tomography (PET). We aimed to explore the tumor detection rate of [(18)F]FSPG in patients relative to 2-[(18)F]fluoro-2-deoxyglucose ([(18)F]FDG). The correlation of [(18)F]FSPG uptake with immunohistochemical expression of x(C)(-) transporter and CD44, which stabilizes the xCT subunit of system x(C)(-), was also analyzed. Patients with non-small cell lung cancer (NSCLC, n = 10) or breast cancer (n = 5) who had a positive [(18)F]FDG uptake were included in this exploratory study. PET images were acquired following injection of approximately 300 MBq [(18)F]FSPG. Immunohistochemistry was done using xCT- and CD44-specific antibody. [(18)F]FSPG PET showed high uptake in the kidney and pancreas with rapid blood clearance. [(18)F]FSPG identified all 10 NSCLC and three of the five breast cancer lesions that were confirmed by pathology. [(18)F]FSPG detected 59 of 67 (88%) [(18)F]FDG lesions in NSCLC, and 30 of 73 (41%) in breast cancer. Seven lesions were additionally detected only on [(18)F]FSPG in NSCLC. The tumor-to-blood pool standardized uptake value (SUV) ratio was not significantly different from that of [(18)F]FDG in NSCLC; however, in breast cancer, it was significantly lower (P < 0.05). The maximum SUV of [(18)F]FSPG correlated significantly with the intensity of immunohistochemical staining of x(C)(-) transporter and CD44 (P < 0.01). [(18)F]FSPG seems to be a promising tracer with a relatively high cancer detection rate in patients with NSCLC. [(18)F]FSPG PET may assess x(C)(-) transporter activity in patients with cancer.

  12. Violin f-hole contribution to far-field radiation via patch near-field acoustical holography.

    Science.gov (United States)

    Bissinger, George; Williams, Earl G; Valdivia, Nicolas

    2007-06-01

    The violin radiates either from dual ports (f-holes) or via surface motion of the corpus (top+ribs+back), with no clear delineation between these sources. Combining "patch" near-field acoustical holography over just the f-hole region of a violin with far-field radiativity measurements over a sphere, it was possible to separate f-hole from surface motion contributions to the total radiation of the corpus below 2.6 kHz. A0, the Helmholtz-like lowest cavity resonance, radiated essentially entirely through the f-holes as expected while A1, the first longitudinal cavity mode with a node at the f-holes, had no significant f-hole radiation. The observed A1 radiation comes from an indirect radiation mechanism, induced corpus motion approximately mirroring the cavity pressure profile seen for violinlike bowed string instruments across a wide range of sizes. The first estimates of the fraction of radiation from the f-holes F(f) indicate that some low frequency corpus modes thought to radiate only via surface motion (notably the first corpus bending modes) had significant radiation through the f-holes, in agreement with net volume changes estimated from experimental modal analysis. F(f) generally trended lower with increasing frequency, following corpus mobility decreases. The f-hole directivity (top/back radiativity ratio) was generally higher than whole-violin directivity.

  13. Comparing a phased combination of acoustical radiosity and the image source method with other simulation tools

    DEFF Research Database (Denmark)

    Marbjerg, Gerd Høy; Brunskog, Jonas; Jeong, Cheol-Ho

    2015-01-01

    A phased combination of acoustical radiosity and the image source method (PARISM) has been developed in order to be able to model both specular and diffuse reflections with angle-dependent and complex-valued acoustical descriptions of the surfaces. It is of great interest to model both specular...

  14. Reactions UF{sub 4} - ClF, UF{sub 4} - ClF{sub 3}, UF{sub 5} - ClF, UF{sub 5} - ClF{sub 3}; Reactions UF{sub 4} - ClF, UF{sub 4} - ClF{sub 3}, UF{sub 5} - ClF, UF{sub 5} - ClF{sub 3}

    Energy Technology Data Exchange (ETDEWEB)

    Luce, M; Benoit, R; Hartmanshenn, O [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1968-07-01

    The reaction between ClF{sub 3} and UF{sub 4} is partially explained by the study of the reactions of the three systems: UF{sub 4}-ClF, UF{sub 5}-ClF and UF{sub 5}-ClF{sub 3}. The analytical techniques used are: the micro-sublimation, the infra-red spectroscopy and the thermogravimetry. The origin of the by-products is indicated. (authors) [French] La reaction entre ClF{sub 3} et UF{sub 4} est partiellement expliquee grace a l'etude des reactions des trois systemes UF{sub 4}-ClF, UF{sub 5}-ClF et UF{sub 5}-ClF{sub 3}. Les techniques analytiques utilisees sont: la micro-sublimation, la spectroscopie infrarouge et la thermogravimetrie. L'origine des sous-produits est indiquee. (auteurs)

  15. Detection of Breast Microcalcifications Under Ultrasound Using Power Doppler and Acoustic Resonance Imaging

    National Research Council Canada - National Science Library

    Weinstein, Susan

    2003-01-01

    .... Our goal with our current project was to utilize breast sonography coupled with the technique of acoustic resonance to image and evaluate the breast micorcalcifications in patients prior to biopsy...

  16. Evaluation of F-18-labeled 5-iodocytidine ({sup 18}F-FIAC) as a new potential positron emission tomography probe for herpes simplex virus type 1 thymidine kinase imaging

    Energy Technology Data Exchange (ETDEWEB)

    Chan, Pei-Chia; Wu, Chun-Yi; Chang, Wen-Yi; Chang, Wei-Ting [Department of Biomedical Imaging and Radiological Sciences, National Yang-Ming University, Taipei, 11221, Taiwan (China); Alauddin, Mian [Department of Experimental Diagnostic Imaging, MD Anderson Cancer Center, University of Texas, TX, 77054 (United States); Liu, Ren-Shan [Department of Biomedical Imaging and Radiological Sciences, National Yang-Ming University, Taipei, 11221, Taiwan (China); Department of Nuclear Medicine, Faculty of Medicine, National Yang-Ming University, Taipei, 11221, Taiwan (China); Department of Nuclear Medicine and National PET/Cyclotron Center, Taipei Veterans General Hospital, Taipei, 11217, Taiwan (China); Lin, Wuu-Jyh [Institute of Nuclear Energy Research, Atomic Energy Council, Taoyuan, 32546, Taiwan (China); Chen, Fu-Du [College of Health and Leisure Science, TransWorld University, Yunlin, 64063, Taiwan (China); Chen, Chuan-Lin, E-mail: clchen2@ym.edu.tw [Department of Biomedical Imaging and Radiological Sciences, National Yang-Ming University, Taipei, 11221, Taiwan (China); Wang, Hsin-Ell, E-mail: hewang@ym.edu.tw [Department of Biomedical Imaging and Radiological Sciences, National Yang-Ming University, Taipei, 11221, Taiwan (China)

    2011-10-15

    Objective: Herpes simplex virus type 1 thymidine kinase (HSV1-tk) gene in combination with radiolabeled nucleoside substrates is the most widely used reporter system. This study characterized 1-(2'-deoxy-2'-[{sup 18}F]fluoro-{beta}-D-arabinofuranosyl)-5-iodocytosine ({sup 18}F-FIAC) as a new potential positron emission tomography (PET) probe for HSV1-tk gene imaging and compared it with 2'-deoxy-2'-[{sup 18}F]fluoro-5-iodo-1-{beta}-D-arabinofuranosyluracil ({sup 18}F-FIAU) and 2'-deoxy-2'-[{sup 18}F]fluoro-5-ethyl-1-{beta}-D-arabinofuranosyluracil({sup 18}F-FEAU) (thymidine analogues) in an NG4TL4-WT/STK sarcoma-bearing mouse model. Methods: A cellular uptake assay, biodistribution study, radioactive metabolites assay and microPET imaging of NG4TL4-WT/STK tumor-bearing mice post administration of {sup 18}F-FIAC, {sup 18}F-FIAU and {sup 18}F-FEAU were conducted to characterize the biological properties of these tracers. Results: Highly specific uptake of {sup 18}F-FIAC, {sup 18}F-FIAU and {sup 18}F-FEAU in tk-transfected [tk(+)] cells was observed. The tk(+)-to-tk(-) cellular uptake ratio after a 2-h incubation was 66.6{+-}25.1, 76.3{+-}18.2 and 247.2{+-}37.2, respectively. In biodistribution studies, {sup 18}F-FIAC showed significant tk(+) tumor specificity (12.6; expressed as the tk(+)-to-tk(-) tumor uptake ratio at 2 h postinjection) comparable with {sup 18}F-FIAU (15.8) but lower than {sup 18}F-FEAU (48.0). The results of microPET imaging also revealed the highly specific accumulation of these three radioprobes in the NG4TL4-tk(+) tumor. Conclusion: Our findings suggested that the cytidine analogue {sup 18}F-FIAC is a new potential PET probe for the imaging of HSV1-tk gene expression. {sup 18}F-FIAC may be regarded as the prodrug of {sup 18}F-FIAU in vivo.

  17. Water-stable NaLuF4-based upconversion nanophosphors with long-term validity for multimodal lymphatic imaging.

    Science.gov (United States)

    Zhou, Jing; Zhu, Xingjun; Chen, Min; Sun, Yun; Li, Fuyou

    2012-09-01

    Multimodal imaging is rapidly becoming an important tool for biomedical applications because it can compensate for the deficiencies of individual imaging modalities. Herein, multifunctional NaLuF(4)-based upconversion nanoparticles (Lu-UCNPs) were synthesized though a facile one-step microemulsion method under ambient condition. The doping of lanthanide ions (Gd(3+), Yb(3+) and Er(3+)/Tm(3+)) endows the Lu-UCNPs with high T(1)-enhancement, bright upconversion luminescence (UCL) emissions, and excellent X-ray absorption coefficient. Moreover, the as-prepared Lu-UCNPs are stable in water for more than six months, due to the protection of sodium glutamate and diethylene triamine pentacetate acid (DTPA) coordinating ligands on the surface. Lu-UCNPs have been successfully applied to the trimodal CT/MR/UCL lymphatic imaging on the modal of small animals. It is worth noting that Lu-UCNPs could be used for imaging even after preserving for over six months. In vitro transmission electron microscope (TEM), methyl thiazolyl tetrazolium (MTT) assay and histological analysis demonstrated that Lu-UCNPs exhibited low toxicity on living systems. Therefore, Lu-UCNPs could be multimodal agents for CT/MR/UCL imaging, and the concept can be served as a platform technology for the next-generation of probes for multimodal imaging. Copyright © 2012 Elsevier Ltd. All rights reserved.

  18. Effect of 18F-FDG dosage alternation on final PET image

    International Nuclear Information System (INIS)

    Yin Dayi; Yao Shulin; Chen Yingmao; Shao Mingzhe; Tian Jiahe

    2002-01-01

    Objective: To assess PET reconstructed image effected by different 18 F-FDG dosages with quantitative and qualitative analysis. Methods: To perform PET phantom acquisition by routine clinical parameters after filled with different doses of 18 F-FDG solution. An identical slice was extracted from reconstructed image for doing following analysis: the hot area standard uptake value (SUV), the ratio of hot area to cold area, the standard deviation on background area, the ratio of true coincidence to random. Results: 296 MBq: The image uniformity was terribly worse, T/R=0.83, other indexes were irregular. 148 MBq: The image presentation looked like the image without attenuation correction, T/R=1.64, other indexes were moderate. 74, 37 and 18.5 MBq: The images were with excellent uniformity, resolution and contrast, the background noise was suitable, all of the quantitative indexes were good. 9.25 and 4.625 MBq: The uniformity and resolution was degraded terribly because of the higher noise and lower information. Conclusion: Combining above results with other considerations, such as radiation exposure, information amount and acquisition time, the authors think the optimal dosage should be 4.625-11.1 MBq/kg

  19. Imaging malignant melanoma with {sup 18}F-5-FPN

    Energy Technology Data Exchange (ETDEWEB)

    Feng, Hongyan; Xia, Xiaotian; Li, Chongjiao; Song, Yiling; Qin, Chunxia; Liu, Qingyao; Zhang, Yongxue; Lan, Xiaoli [Department of Nuclear Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology (China); Hubei Key Laboratory of Molecular Imaging (China)

    2016-01-15

    Radiolabelled benzamides are attractive candidates for targeting melanoma because they bind to melanin and exhibit high tumour uptake and retention. {sup 18}F-5-Fluoro-N-(2-[diethylamino]ethyl)picolinamide ({sup 18}F-5-FPN), a benzamide analogue, was prepared and its pharmacokinetics and binding affinity evaluated both in vitro and in vivo to assess its clinical potential in the diagnosis and staging of melanoma. {sup 18}F-5-FPN was prepared and purified. Its binding specificity was measured in vitro in two different melanoma cell lines, one pigmented (B16F10 cells) and one nonpigmented (A375m cells), and in vivo in mice xenografted with the same cell lines. Dynamic and static PET images using {sup 18}F-5-FPN were obtained in the tumour-bearing mice, and the static images were also compared with those acquired with {sup 18}F-FDG. PET imaging with {sup 18}F-5-FPN was also performed in B16F10 tumour-bearing mice with lung metastases. {sup 18}F-5-FPN was successfully prepared with radiochemical yields of 5 - 10 %. Binding of {sup 18}F-5-FPN to B16F10 cells was much higher than to A375m cells. On dynamic PET imaging B16F10 tumours were visible about 1 min after injection of the tracer, and the uptake gradually increased over time. {sup 18}F-5-FPN was rapidly excreted via the kidneys. B16F10 tumours were clearly visible on static images acquired 1 and 2 h after injection, with high uptake values of 24.34 ± 6.32 %ID/g and 16.63 ± 5.41 %ID/g, respectively, in the biodistribution study (five mice). However, there was no visible uptake by A375m tumours. {sup 18}F-5-FPN and {sup 18}F-FDG PET imaging were compared in B16F10 tumour xenografts, and the tumour-to-background ratio of {sup 18}F-5-FPN was ten times higher than that of {sup 18}F-FDG (35.22 ± 7.02 vs. 3.29 ± 0.53, five mice). {sup 18}F-5-FPN PET imaging also detected simulated lung metastases measuring 1 - 2 mm. {sup 18}F-5-FPN specifically targeted melanin in vitro and in vivo with high retention and affinity

  20. In vivo19F MR imaging and spectroscopy for the BNCT optimization

    International Nuclear Information System (INIS)

    Porcari, P.; Capuani, S.; D'Amore, E.; Lecce, M.; La Bella, A.; Fasano, F.; Migneco, L.M.; Campanella, R.; Maraviglia, B.; Pastore, F.S.

    2009-01-01

    The aim of this study was to evaluate in vivo the boron biodistribution and pharmacokinetics of 4-borono-2-fluorophenylalanine ( 19 F-BPA) using 19 F MR Imaging ( 19 F MRI) and Spectroscopy ( 19 F MRS). The correlation between the results obtained by both techniques, 19 F MRI on rat brain and 19 F MRS on blood samples, showed the maximum 19 F-BPA uptake in C6 glioma model at 2.5 h after infusion determining the optimal irradiation time. Moreover, the effect of L-DOPA as potential enhancer of 19 F-BPA tumour intake was assessed using 19 F MRI.

  1. N-(N-benzylpiperidin-4-yl)-2-[18F]fluorobenzamide: A potential ligand for PET imaging of σ receptors

    International Nuclear Information System (INIS)

    Shiue Chyngyann; Shiue, Grace G.; Zhang, Sue X.; Wilder, Susan; Greenberg, Joel H.; Benard, Francois; Wortman, Jeffrey A.; Alavi, Abass A.

    1997-01-01

    Four nitro- and fluorobenzamides (1-4) have been synthesized in good yields from nitro- and fluoro-substituted benzoyl chloride with 4-amino-1-benzylpiperidine. In vitro studies showed that these compounds have high affinities to σ receptors. N-(N-Benzylpiperidin-4-yl)-2-fluorobenzamide (3), in particular, bound to σ receptors with high affinity (K i = 3.4 nM, guinea pig brain membranes) and high selectivity (σ-2/σ-1 = 120). It was, therefore, labeled with 18 F and evaluated as a σ receptor radioligand. N-(N-Benzylpiperidin-4-yl)-2-[ 18 F]fluorobenzamide (3a) was synthesized in one step by nucleophilic substitution of the 2-nitro precursor (1) with [ 18 F]fluoride in DMSO at 140 deg. C for 20 min followed by purification with HPLC in 4-10% yield (decay corrected). The synthesis time was 90 min and the specific activity was 0.4-1.0 Ci/μmol. Tissue distribution in mice revealed that the uptakes of 3a in the brain, heart, liver, lungs, spleen, kidneys and small intestine were high, and the radioactivity in these organs remained constant from 60 to 120 min post-injection. The radioactivity in the bone did not significantly increase, suggesting in vivo defluorination may not be the major route of metabolism of 3a in mice. Blocking studies with haloperidol in rats indicated that the uptake of compound 3a in the rat brain was selective to haloperidol-sensitive σ sites. These results suggest that compound 3a is a potent σ receptor radioligand and may be a potential ligand for PET imaging of σ receptors in humans

  2. Auralisations with loudspeaker arrays from a phased combination of the image source method and acoustical radiosity

    DEFF Research Database (Denmark)

    Marbjerg, Gerd Høy

    2017-01-01

    In order to create a simulation tool that is well-suited for small rooms with low diffusion and highly absorbing ceilings, a new room acoustic simulation tool has been developed that combines a phased version of the image source with acoustical radiosity and that considers the angle dependence...... impulse response, because more directional information is available with acoustical radiosity. Small rooms with absorbing surfaces are tested, because this is the room type that PARISM is particularly useful for....

  3. Acoustic emission linear pulse holography

    Science.gov (United States)

    Collins, H.D.; Busse, L.J.; Lemon, D.K.

    1983-10-25

    This device relates to the concept of and means for performing Acoustic Emission Linear Pulse Holography, which combines the advantages of linear holographic imaging and Acoustic Emission into a single non-destructive inspection system. This unique system produces a chronological, linear holographic image of a flaw by utilizing the acoustic energy emitted during crack growth. The innovation is the concept of utilizing the crack-generated acoustic emission energy to generate a chronological series of images of a growing crack by applying linear, pulse holographic processing to the acoustic emission data. The process is implemented by placing on a structure an array of piezoelectric sensors (typically 16 or 32 of them) near the defect location. A reference sensor is placed between the defect and the array.

  4. Effect of Genetic Variability in the CYP4F2, CYP4F11, and CYP4F12 Genes on Liver mRNA Levels and Warfarin Response

    Directory of Open Access Journals (Sweden)

    J. E. Zhang

    2017-05-01

    Full Text Available Genetic polymorphisms in the gene encoding cytochrome P450 (CYP 4F2, a vitamin K oxidase, affect stable warfarin dose requirements and time to therapeutic INR. CYP4F2 is part of the CYP4F gene cluster, which is highly polymorphic and exhibits a high degree of linkage disequilibrium, making it difficult to define causal variants. Our objective was to examine the effect of genetic variability in the CYP4F gene cluster on expression of the individual CYP4F genes and warfarin response. mRNA levels of the CYP4F gene cluster were quantified in human liver samples (n = 149 obtained from a well-characterized liver bank and fine mapping of the CYP4F gene cluster encompassing CYP4F2, CYP4F11, and CYP4F12 was performed. Genome-wide association study (GWAS data from a prospective cohort of warfarin-treated patients (n = 711 was also analyzed for genetic variations across the CYP4F gene cluster. In addition, SNP-gene expression in human liver tissues and interactions between CYP4F genes were explored in silico using publicly available data repositories. We found that SNPs in CYP4F2, CYP4F11, and CYP4F12 were associated with mRNA expression in the CYP4F gene cluster. In particular, CYP4F2 rs2108622 was associated with increased CYP4F2 expression while CYP4F11 rs1060467 was associated with decreased CYP4F2 expression. Interestingly, these CYP4F2 and CYP4F11 SNPs showed similar effects with warfarin stable dose where CYP4F11 rs1060467 was associated with a reduction in daily warfarin dose requirement (∼1 mg/day, Pc = 0.017, an effect opposite to that previously reported with CYP4F2 (rs2108622. However, inclusion of either or both of these SNPs in a pharmacogenetic algorithm consisting of age, body mass index (BMI, gender, baseline clotting factor II level, CYP2C9∗2 rs1799853, CYP2C9∗3 rs1057910, and VKORC1 rs9923231 improved warfarin dose variability only by 0.5–0.7% with an improvement in dose prediction accuracy of ∼1–2%. Although there is complex

  5. One-Step 18F-Labeling of Estradiol Derivative for PET Imaging of Breast Cancer

    Directory of Open Access Journals (Sweden)

    Hongbo Huang

    2018-01-01

    Full Text Available Positron emission tomography (PET imaging is a useful method to evaluate in situ estrogen receptor (ER status for the early diagnosis of breast cancer and optimization of the appropriate treatment strategy. The 18F-labeled estradiol derivative has been successfully used to clinically assess the ER level of breast cancer. In order to simplify the radiosynthesis process, one-step 18F-19F isotope exchange reaction was employed for the 18F-fluorination of the tracer of [18F]AmBF3-TEG-ES. The radiotracer was obtained with the radiochemical yield (RCY of ~61% and the radiochemical purity (RCP of >98% within 40 min. Cell uptake and blocking assays indicated that the tracer could selectively accumulate in the ER-positive human breast cancer cell lines MCF-7 and T47D. In vivo PET imaging on the MCF-7 tumor-bearing mice showed relatively high tumor uptake (1.4~2.3 %D/g and tumor/muscle uptake ratio (4~6. These results indicated that the tracer is a promising PET imaging agent for ER-positive breast cancers.

  6. Evaluation of 4-[(18)F]fluorobenzoyl-FALGEA-NH(2) as a positron emission tomography tracer for epidermal growth factor receptor mutation variant III imaging in cancer

    DEFF Research Database (Denmark)

    Denholt, Charlotte Lund; Binderup, Tina; Stockhausen, Marie-Thérése

    2011-01-01

    This study describes the radiosynthesis, in vitro and in vivo evaluation of the novel small peptide radioligand, 4-[(18)F]fluorobenzoyl-Phe-Ala-Leu-Gly-Glu-Ala-NH(2,) ([(18)F]FBA-FALGEA-NH(2)) as a positron emission tomography (PET) tracer for imaging of the cancer specific epidermal growth facto...

  7. Multi-crack imaging using nonclassical nonlinear acoustic method

    Science.gov (United States)

    Zhang, Lue; Zhang, Ying; Liu, Xiao-Zhou; Gong, Xiu-Fen

    2014-10-01

    Solid materials with cracks exhibit the nonclassical nonlinear acoustical behavior. The micro-defects in solid materials can be detected by nonlinear elastic wave spectroscopy (NEWS) method with a time-reversal (TR) mirror. While defects lie in viscoelastic solid material with different distances from one another, the nonlinear and hysteretic stress—strain relation is established with Preisach—Mayergoyz (PM) model in crack zone. Pulse inversion (PI) and TR methods are used in numerical simulation and defect locations can be determined from images obtained by the maximum value. Since false-positive defects might appear and degrade the imaging when the defects are located quite closely, the maximum value imaging with a time window is introduced to analyze how defects affect each other and how the fake one occurs. Furthermore, NEWS-TR-NEWS method is put forward to improve NEWS-TR scheme, with another forward propagation (NEWS) added to the existing phases (NEWS and TR). In the added phase, scanner locations are determined by locations of all defects imaged in previous phases, so that whether an imaged defect is real can be deduced. NEWS-TR-NEWS method is proved to be effective to distinguish real defects from the false-positive ones. Moreover, it is also helpful to detect the crack that is weaker than others during imaging procedure.

  8. Folic acid-targeted magnetic Tb-doped CeF3 fluorescent nanoparticles as bimodal probes for cellular fluorescence and magnetic resonance imaging.

    Science.gov (United States)

    Ma, Zhi-Ya; Liu, Yu-Ping; Bai, Ling-Yu; An, Jie; Zhang, Lin; Xuan, Yang; Zhang, Xiao-Shuai; Zhao, Yuan-Di

    2015-10-07

    Magnetic fluorescent nanoparticles (NPs) have great potential applications for diagnostics, imaging and therapy. We developed a facile polyol method to synthesize multifunctional Fe3O4@CeF3:Tb@CeF3 NPs with small size (CA) to obtain carboxyl-functionalized NPs (Fe3O4@CeF3:Tb@CeF3-COOH). Folic acid (FA) as an affinity ligand was then covalently conjugated onto NPs to yield Fe3O4@CeF3:Tb@CeF3-FA NPs. They were then applied as multimodal imaging agents for simultaneous in vitro targeted fluorescence imaging and magnetic resonance imaging (MRI) of HeLa cells with overexpressed folate receptors (FR). The results indicated that these NPs had strong luminescence and enhanced T2-weighted MR contrast and would be promising candidates as multimodal probes for both fluorescence and MRI imaging.

  9. Auralizations with loudspeaker arrays from a phased combination of the image source method and acoustical radiosity

    DEFF Research Database (Denmark)

    Marbjerg, Gerd Høy; Brunskog, Jonas; Jeong, Cheol-Ho

    2017-01-01

    In order to create a simulation tool that is well-suited for small rooms with low diffusion and highly absorbing ceilings, a new room acoustic simulation tool has been developed that combines a phased version of the image source with acoustical radiosity and that considers the angle dependence...... of the PARISM impulse response, because more directional information is available with acoustical radiosity. Small rooms with absorbing surfaces are tested, because this is the room type that PARISM is particularly useful for....

  10. Imaging Bone–Cartilage Interactions in Osteoarthritis Using [18F]-NaF PET-MRI

    Directory of Open Access Journals (Sweden)

    Dragana Savic MSc

    2016-12-01

    Full Text Available Purpose: Simultaneous positron emission tomography–magnetic resonance imaging (PET-MRI is an emerging technology providing both anatomical and functional images without increasing the scan time. Compared to the traditional PET/computed tomography imaging, it also exposes the patient to significantly less radiation and provides better anatomical images as MRI provides superior soft tissue characterization. Using PET-MRI, we aim to study interactions between cartilage composition and bone function simultaneously, in knee osteoarthritis (OA. Procedures: In this article, bone turnover and remodeling was studied using [18F]-sodium fluoride (NaF PET data. Quantitative MR-derived T1ρ relaxation times characterized the biochemical cartilage degeneration. Sixteen participants with early signs of OA of the knee received intravenous injections of [18F]-NaF at the onset of PET-MR image acquisition. Regions of interest were identified, and kinetic analysis of dynamic PET data provided the rate of uptake (Ki and the normalized uptake (standardized uptake value of [18F]-NaF in the bone. Morphological MR images and quantitative voxel-based T1ρ maps of cartilage were obtained using an atlas-based registration technique to segment cartilage automatically. Voxel-by-voxel statistical parameter mapping was used to investigate the relationship between bone and cartilage. Results: Increases in cartilage T1ρ, indicating degenerative changes, were associated with increased turnover in the adjoining bone but reduced turnover in the nonadjoining compartments. Associations between pain and increased bone uptake were seen in the absence of morphological lesions in cartilage, but the relationship was reversed in the presence of incident cartilage lesions. Conclusion: This study shows significant cartilage and bone interactions in OA of the knee joint using simultaneous [18F]-NaF PET-MR, the first in human study. These observations highlight the complex biomechanical and

  11. Biodistribution and PET imaging of [18F]-fluoroadenosine derivatives

    International Nuclear Information System (INIS)

    Alauddin, Mian M.; Shahinian, Antranik; Park, Ryan; Tohme, Michael; Fissekis, John D.; Conti, Peter S.

    2007-01-01

    Introduction: Many fluorinated analogues of adenosine nucleoside have been synthesized and studied as potential antitumor and antiviral agents. Earlier, we reported radiosynthesis of 2'-deoxy-2'-[ 18 F]fluoro-1-β-D-arabinofuranosyl-adenine ([ 18 F]-FAA) and 3'-deoxy-3'-[ 18 F]fluoro-1-β-D-xylofuranosyl-adenine ([ 18 F]FXA). Now, we report their in vivo studies including blood clearance, biodistribution and micro-PET imaging in tumor-bearing nude mice. Methods: Tumors were grown in 6-week-old athymic nude mice (Harlan, Indianapolis, IN, USA) by inoculation of HT-29 cells, wild-type cells in the left flank and transduced cells with HSV-tk on the right flank. When the tumor was about 1 cm in size, animals were injected with these radiotracers for in vivo studies, including blood clearance, micro-PET imaging and biodistribution. Results: Uptake of [ 18 F]FAA in tumor was 3.3-fold higher than blood, with highest uptake in the spleen. Maximum uptake of [ 18 F]FXA was observed in the heart compared to other organs. There was no tumor uptake of [ 18 F]FXA. Biodistribution results were supported by micro-PET images, which also showed very high uptake of [ 18 F]FAA in spleen and visualization of tumors, and high uptake of [ 18 F]FXA in the heart. Conclusion: These results suggest that [ 18 F]FAA may be useful for tumor imaging, while [ 18 F]FXA may have potential as a heart imaging agent with PET

  12. Nicotinic α4β2 receptor imaging agents

    International Nuclear Information System (INIS)

    Pichika, Rama; Easwaramoorthy, Balasubramaniam; Collins, Daphne; Christian, Bradley T.; Shi, Bingzhi; Narayanan, Tanjore K.; Potkin, Steven G.; Mukherjee, Jogeshwar

    2006-01-01

    The α4β2 nicotinic acetylcholine receptor (nAChR) has been implicated in various neurodegenerative diseases. Optimal positron emission tomography (PET) imaging agents are therefore highly desired for this receptor. We report here the development and initial evaluation of 2-fluoro-3-[2-((S)-3-pyrrolinyl)methoxy]pyridine (nifene). In vitro binding affinity of nifene in rat brain homogenate using 3 H-cytisine exhibited a K i =0.50 nM for the α4β2 sites. The radiosynthesis of 2- 18 F-fluoro-3-[2-((S)-3-pyrrolinyl)methoxy]pyridine ( 18 F-nifene) was accomplished in 2.5 h with an overall radiochemical yield of 40-50%, decay corrected. The specific activity was estimated to be approx. 37-185 GBq/μmol. In vitro autoradiography in rat brain slices indicated selective binding of 18 F-nifene to anteroventral thalamic (AVT) nucleus, thalamus, subiculum, striata, cortex and other regions consistent with α4β2 receptor distribution. Rat cerebellum showed some binding, whereas regions in the hippocampus had the lowest binding. The highest ratio of >13 between AVT and cerebellum was measured for 18 F-nifene in rat brain slices. The specific binding was reduced (>95%) by 300 μM nicotine in these brain regions. Positron emission tomography imaging study of 18 F-nifene (130 MBq) in anesthetized rhesus monkey was carried out using an ECAT EXACT HR+ scanner. PET study showed selective maximal uptake in the regions of the anterior medial thalamus, ventro-lateral thalamus, lateral geniculate, cingulate gyrus, temporal cortex including the subiculum. The cerebellum in the monkeys showed lower binding than the other regions. Thalamus-to-cerebellum ratio peaked at 30-35 min postinjection to a value of 2.2 and subsequently reduced. The faster binding profile of 18 F-nifene indicates promise as a PET imaging agent and thus needs further evaluation

  13. Oncological applications of 18F-FDG PET imaging

    International Nuclear Information System (INIS)

    Li Lin

    2000-01-01

    Considering normal distribution of 18 F-FDG in human body, 18 F-FDG imaging using PET can be applied to brain tumors, colorectal cancer, lymphoma, melanoma, lung cancer and head and neck cancer. The author briefly focuses on application of 18 F-FDG PET imaging to breast cancer, pancreatic cancer, hepatocellular carcinoma, musculoskeletal neoplasms, endocrine neoplasms, genitourinary neoplasms, esophageal and gastric carcinomas

  14. Radiopharmacological evaluation of 18F-labeled phosphatidylserine-binding peptides for molecular imaging of apoptosis

    International Nuclear Information System (INIS)

    Wuest, Melinda; Perreault, Amanda; Kapty, Janice; Richter, Susan; Foerster, Christian; Bergman, Cody; Way, Jenilee; Mercer, John; Wuest, Frank

    2015-01-01

    Introduction: Radiolabeled phosphatidylserine (PS)-binding peptides represent an innovative strategy for molecular imaging of apoptosis with positron emission tomography (PET). The goal of this study was the radiopharmacological evaluation of radiolabeled peptides for their binding to PS on apoptotic cancer cells, involving metabolic stability, cellular uptake, biodistribution, and dynamic PET imaging experiments. Methods: Binding of peptides LIKKPF, PGDLSR, FBz-LIKKPF, FBz-PGDLSR, FBAM-CLIKKPF and FBAM-CPGDLSR to PS was analyzed in a newly developed radiometric binding assay using 64 Cu-labeled wild-type annexin-V as radiotracer. Radiolabeling of most potent peptides with fluorine-18 was carried out with thiol-selective prosthetic group [ 18 F]FBAM to give [ 18 F]FBAM-CLIKKPF and [ 18 F]FBAM-CPGDLSR. [ 18 F]FBAM-labeled peptides were studied in camptothecin-induced apoptotic human T lymphocyte Jurkat cells, and in a murine EL4 tumor model of apoptosis using dynamic PET imaging and biodistribution. Results: Peptides LIKKPF and PGDLSR inhibited binding of 64 Cu-labeled annexin-V to immobilized PS in the millimolar range (IC 50 10–15 mM) compared to annexin-V (45 nM). Introduction of FBAM prosthetic group slightly increased inhibitory potencies (FBAM-CLIKKPF: IC 50 = 1 mM; FBAM-CPGDLSR: IC 50 = 6 mM). Radiolabeling succeeded in good radiochemical yields of 50–54% using a chemoselective alkylation reaction of peptides CLIKKPF and CPGDLSR with [ 18 F]FBAM. In vivo metabolic stability studies in mice revealed 40–60% of intact peptides at 5 min p.i. decreasing to 25% for [ 18 F]FBAM-CLIKKPF and less than 5% for [ 18 F]FBAM-CPGDLSR at 15 min p.i.. Cell binding of [ 18 F]FBAM-CLIKKPF in drug-treated Jurkat cells was significantly higher compared to untreated cells, but this was not observed for [ 18 F]FBAM-CPGDLSR. Dynamic PET imaging experiments showed that baseline uptake of [ 18 F]FBAM-CLIKKPF in EL4 tumors was higher (SUV 5min 0.46, SUV 60min 0.13) compared to

  15. The Acoustic Lens Design and in Vivo Use of a Multifunctional Catheter Combining Intracardiac Ultrasound Imaging and Electrophysiology Sensing

    Science.gov (United States)

    Stephens, Douglas N.; Cannata, Jonathan; Liu, Ruibin; Zhao, Jian Zhong; Shung, K. Kirk; Nguyen, Hien; Chia, Raymond; Dentinger, Aaron; Wildes, Douglas; Thomenius, Kai E.; Mahajan, Aman; Shivkumar, Kalyanam; Kim, Kang; O’Donnell, Matthew; Sahn, David

    2009-01-01

    A multifunctional 9F intracardiac imaging and electrophysiology mapping catheter was developed and tested to help guide diagnostic and therapeutic intracardiac electrophysiology (EP) procedures. The catheter tip includes a 7.25-MHz, 64-element, side-looking phased array for high resolution sector scanning. Multiple electrophysiology mapping sensors were mounted as ring electrodes near the array for electrocardiographic synchronization of ultrasound images. The catheter array elevation beam performance in particular was investigated. An acoustic lens for the distal tip array designed with a round cross section can produce an acceptable elevation beam shape; however, the velocity of sound in the lens material should be approximately 155 m/s slower than in tissue for the best beam shape and wide bandwidth performance. To help establish the catheter’s unique ability for integration with electrophysiology interventional procedures, it was used in vivo in a porcine animal model, and demonstrated both useful intracardiac echocardiographic visualization and simultaneous 3-D positional information using integrated electroanatomical mapping techniques. The catheter also performed well in high frame rate imaging, color flow imaging, and strain rate imaging of atrial and ventricular structures. PMID:18407850

  16. Statistics of the acoustic emission signals parameters from Zircaloy-4 fuel cladding

    International Nuclear Information System (INIS)

    Oliveto, Maria E.; Lopez Pumarega, Maria I.; Ruzzante, Jose E.

    2000-01-01

    Statistic analysis of acoustic emission signals parameters: amplitude, duration and risetime was carried out. CANDU type Zircaloy-4 fuel claddings were pressurized up to rupture, one set of five normal pieces and six with defects included, acoustic emission was used on-line. Amplitude and duration frequency distributions were fitted with lognormal distribution functions, and risetime with an exponential one. Using analysis of variance, acoustic emission was appropriated to distinguish between defective and non-defective subsets. Clusters analysis applied on mean values of acoustic emission signal parameters were not effective to distinguish two sets of fuel claddings studied. (author)

  17. 4-[18F]Fluorophenylpiperazines by Improved Hartwig-Buchwald N-Arylation of 4-[18F]fluoroiodobenzene, Formed via Hypervalent λ3-Iodane Precursors: Application to Build-Up of the Dopamine D4 Ligand [18F]FAUC 316

    Directory of Open Access Journals (Sweden)

    Fabian Kügler

    2014-12-01

    Full Text Available Substituted phenylpiperazines are often neuropharmacologically active compounds and in many cases are essential pharmacophores of neuroligands for different receptors such as D2-like dopaminergic, serotoninergic and other receptors. Nucleophilic, no-carrier-added (n.c.a. 18F-labelling of these ligands in an aromatic position is desirable for studying receptors with in vivo molecular imaging. 1-(4-[18F]Fluorophenylpiperazine was synthesized in two reaction steps starting by 18F-labelling of a iodobenzene-iodonium precursor, followed by Pd-catalyzed N-arylation of the intermediate 4-[18F]fluoro-iodobenzene. Different palladium catalysts and solvents were tested with particular attention to the polar solvents dimethylformamide (DMF and dimethylsulfoxide (DMSO. Weak inorganic bases like potassium phosphate or cesium carbonate seem to be essential for the arylation step and lead to conversation rates above 70% in DMF which is comparable to those in typically used toluene. In DMSO even quantitative conversation was observed. Overall radiochemical yields of up to 40% and 60% in DMF and DMSO, respectively, were reached depending on the labelling yield of the first step. The fluorophenylpiperazine obtained was coupled in a third reaction step with 2-formyl-1H-indole-5-carbonitrile to yield the highly selective dopamine D4 ligand [18F]FAUC 316.

  18. Auditory processing in the brainstem and audiovisual integration in humans studied with fMRI

    NARCIS (Netherlands)

    Slabu, Lavinia Mihaela

    2008-01-01

    Functional magnetic resonance imaging (fMRI) is a powerful technique because of the high spatial resolution and the noninvasiveness. The applications of the fMRI to the auditory pathway remain a challenge due to the intense acoustic scanner noise of approximately 110 dB SPL. The auditory system

  19. Thermodynamic assessment of the LiF-NaF-ThF4-UF4 system

    International Nuclear Information System (INIS)

    Benes, O.; Beilmann, M.; Konings, R.J.M.

    2010-01-01

    A thermodynamic assessment of the LiF-NaF-ThF 4 -UF 4 system is presented in this study. The binary phase diagrams are optimized based on the known experimental data and the excess Gibbs energies of liquid and solid solutions are described using a modified quasi chemical model and polynomial formalism respectively. The higher order systems are extrapolated according to asymmetric Toop mathematical formalism. Based on the developed thermodynamic database the fuel composition of the molten salt fast reactor is optimized. In total three different fuel compositions are identified. Properties of these fuel compositions such as melting point, vapour pressure and the boiling temperature are derived from the obtained thermodynamic assessment and are presented in this study.

  20. [68Ga]pentixafor for CXCR4 imaging in a PC-3 prostate cancer xenograft model - comparison with [18F]FDG PET/CT, MRI and ex vivo receptor expression.

    Science.gov (United States)

    Schwarzenböck, Sarah M; Stenzel, Jan; Otto, Thomas; Helldorff, Heike V; Bergner, Carina; Kurth, Jens; Polei, Stefan; Lindner, Tobias; Rauer, Romina; Hohn, Alexander; Hakenberg, Oliver W; Wester, Hans J; Vollmar, Brigitte; Krause, Bernd J

    2017-11-10

    The aim was to characterize the properties of [ 68 Ga]Pentixafor as tracer for prostate cancer imaging in a PC-3 prostate cancer xenograft mouse model and to investigate its correlation with [ 18 F]FDG PET/CT, magnetic resonance imaging (MRI) and ex vivo analyses. Static [ 68 Ga]Pentixafor and [ 18 F]FDG PET as well as morphological/ diffusion weighted MRI and 1 H MR spectroscopy was performed. Imaging data were correlated with ex vivo biodistribution and CXCR4 expression in PC-3 tumors (immunohistochemistry (IHC), mRNA analysis). Flow cytometry was performed for evaluation of localization of CXCR4 receptors ( in vitro PC-3 cell experiments). Tumor uptake of [ 68 Ga]Pentixafor was significantly lower compared to [ 18 F]FDG. Ex vivo CXCR4 mRNA expression of tumors was shown by PCR. Only faint tumor CXCR4 expression was shown by IHC (immuno reactive score of 3). Accordingly, flow cytometry of PC-3 cells revealed only a faint signal, cell membrane permeabilisation showed a slight signal increase. There was no significant correlation of [ 68 Ga]Pentixafor tumor uptake and ex vivo receptor expression. Spectroscopy showed typical spectra of prostate cancer. PC-3 tumor uptake of [ 68 Ga]Pentixafor was existent but lower compared to [ 18 F]FDG. No significant correlation of ex vivo tumor CXCR4 receptor expression and [ 68 Ga]Pentixafor tumor uptake was shown. CXCR4 receptor expression on the surface of PC-3 cells was existent but rather low possibly explaining the limited [ 68 Ga]Pentixafor tumor uptake; receptor localization in the interior of PC-3 cells is presumable as shown by cell membrane permeabilisation. Further studies are necessary to define the role of [ 68 Ga]Pentixafor in prostate cancer imaging.

  1. {sup 18}F-Labelled metomidate analogues as adrenocortical imaging agents

    Energy Technology Data Exchange (ETDEWEB)

    Erlandsson, Maria; Karimi, Farhad [Department of Biochemistry and Organic Chemistry, Uppsala University, Box 576, S-751 23 Uppsala (Sweden); Lindhe, Orjan [Uppsala Imanet, GE Healthcare, Box 967, S-751 09 Uppsala (Sweden); Langstroem, Bengt [Department of Biochemistry and Organic Chemistry, Uppsala University, Box 576, S-751 23 Uppsala (Sweden)], E-mail: bengt.langstrom@biorg.uu.se

    2009-05-15

    Introduction: Two- and one-step syntheses of {sup 18}F-labelled analogues of metomidate, such as 2-[{sup 18}F]fluoroethyl 1-[(1R)-1-phenylethyl]-1H-imidazole-5-carboxylate (1), 2-[{sup 18}F]fluoroethyl 1-[(1R)-1-(4-chlorophenyl)ethyl]-1H-imidazole-5-carboxylate (2), 2-[{sup 18}F]fluoroethyl 1-[(1R)-1-(4-bromophenyl)ethyl]-1H-imidazole-5-carboxylate (3), 3-[{sup 18}F]fluoropropyl 1-[(1R)-1-(4-bromophenyl)ethyl]-1H-imidazole-5-carboxylate (4) and 3-[{sup 18}F]fluoropropyl 1-[(1R)-1-phenylethyl]-1H-imidazole-5-carboxylate (5) are presented. Methods: Analogues 1-5 were prepared by a two-step reaction sequence that started with the synthesis of either 2-[{sup 18}F]fluoroethyl 4-methylbenzenesulfonate or 3-[{sup 18}F]fluoropropyl 4-methylbenzenesulfonate. These were used as {sup 18}F-alkylating agents in the second step, in which they reacted with the ammonium salt of a 1-[(1R)-1-phenylethyl]-1H-imidazole-5-carboxylic acid. One-step-labelling syntheses of 1, 2 and 5 were also explored. Analogues 1-4 were biologically validated by frozen-section autoradiography and organ distribution. Metabolite analysis was performed for 2 and 3. Results: The radiochemical yield of the two-step synthesis was in the range of 10-29% and that of the one-step synthesis was 25-37%. Using microwave irradiation in the one-step synthesis of 1 and 2 increased the radiochemical yield to 46{+-}3% and 79{+-}30%, respectively. Conclusion: Both the frozen-section autoradiography and organ distribution results indicated that analogue 2 has a potential as an adrenocortical imaging agent, having the highest degree of specific adrenal binding and best ratio of adrenal to organ uptake among the compounds studied.

  2. A study on the acoustical holography

    International Nuclear Information System (INIS)

    Shin, S.H.; Lee, J.H.; Jang, M.S.

    1979-01-01

    Theoretical and experimental investigations of acoustical holograms, and the optical reconstruction of their images are described. Acoustical holograms are constructed through the use of sound waves of 14 KHz-16 KHz frequency range. The virtual images and conjugate images are reconstructed using He-Ne gas laser(Wavelength 6,328A) light. The effect on the reconstructed images of the wavelength of the sound waves and of the scanning plane are discussed. Furthermore, the three dimensional information memory in acoustical holograms is discussed. (author)

  3. Scale Model Acoustic Test Validation of IOP-SS Water Prediction using Loci-STREAM-VoF

    Science.gov (United States)

    Nielsen, Tanner; West, Jeff

    2015-01-01

    The Scale Model Acoustic Test (SMAT) is a 5% scale test of the Space Launch System (SLS), which is currently being designed at Marshall Space Flight Center (MSFC). SMAT consists of a 5% scale representation of the ignition overpressure sound-suppression system (IOP-SS) that is being tested to quantify the water flow and induced air entrainment in and around the mobile launcher exhaust hole. This data will be compared with computational fluid dynamics (CFD) simulations using the newly developed Loci-STREAM Volume of Fluid (VoF) methods. Compressible and incompressible VoF methods have been formulated, and are currently being used to simulate the water flow of SMAT IOP-SS. The test data will be used to qualitatively and quantitatively assess and validate the VoF methods.

  4. Density Functional Study of Structures and Electron Affinities of BrO4F/BrO4F-

    Directory of Open Access Journals (Sweden)

    Wei Li

    2009-07-01

    Full Text Available The structures, electron affinities and bond dissociation energies of BrO4F/BrO4F− species have been investigated with five density functional theory (DFT methods with DZP++ basis sets. The planar F-Br…O2…O2 complexes possess 3A' electronic state for neutral molecule and 4A' state for the corresponding anion. Three types of the neutral-anion energy separations are the adiabatic electron affinity (EAad, the vertical electron affinity (EAvert, and the vertical detachment energy (VDE. The EAad value predicted by B3LYP method is 4.52 eV. The bond dissociation energies De (BrO4F → BrO4-mF + Om (m = 1-4 and De- (BrO4F- → BrO4-mF- + Om and BrO4F- → BrO4-mF + Om- are predicted. The adiabatic electron affinities (EAad were predicted to be 4.52 eV for F-Br…O2…O2 (3A'← 4A' (B3LYP method.

  5. Spectroscopic analysis of LiHoF4 and LiErF4

    DEFF Research Database (Denmark)

    Christensen, H.P.

    1979-01-01

    The polarized absorption spectra for Ho3+ and Er3+ in LiHoF4 and LiErF4, respectively, have been recorded in the spectral interval 4000-26 000 cm-1 at 2 K. Parts of the spectra were examined at higher temperatures. The experimental levels for Ho3+ and Er3+ in LiRF4 were close to those found in Li...

  6. Perturbation measurement of waveguides for acoustic thermometry

    Science.gov (United States)

    Lin, H.; Feng, X. J.; Zhang, J. T.

    2013-09-01

    Acoustic thermometers normally embed small acoustic transducers in the wall bounding a gas-filled cavity resonator. At high temperature, insulators of transducers loss electrical insulation and degrade the signal-to-noise ratio. One essential solution to this technical trouble is to couple sound by acoustic waveguides between resonator and transducers. But waveguide will break the ideal acoustic surface and bring perturbations(Δf+ig) to the ideal resonance frequency. The perturbation model for waveguides was developed based on the first-order acoustic theory in this paper. The frequency shift Δf and half-width change g caused by the position, length and radius of waveguides were analyzed using this model. Six different length of waveguides (52˜1763 mm) were settled on the cylinder resonator and the perturbation (Δf+ig) were measured at T=332 K and p=250˜500 kPa. The experiment results agreed with the theoretical prediction very well.

  7. In vivo biodistribution of two [18F]-labelled muscarinic cholinergic receptor ligands: 2-[18F]- and 4-[18F]-fluorodexetimide

    International Nuclear Information System (INIS)

    Wilson, A.A.; Scheffel, U.A.; Dannals, R.F.; Stathis, M.; Ravert, H.T.; Wagner, H.N. Jr.

    1991-01-01

    Two [ 18 F]-labelled analogues of the potent muscarinic cholinergic receptor (m-AChR) antagonist, dexetimide, were evaluated as potential ligands for imaging m-AChR by positron emission tomography (PET). Intravenous administration of both 2-[ 18 F]- or 4-[ 18 F]-fluorodexetimide resulted in high brain uptake of radioactivity in mice. High binding levels were observed in m-AChR rich areas, such as cortex and striatum, with low levels in the receptor-poor cerebellum. Uptake of radioactivity was saturable and could be blocked by pre-administration of dexetimide or atropine. Drugs with different sites of action were ineffective at blocking receptor binding. The results indicate that both radiotracers are promising candidates for use in PET studies

  8. One-step preparation of [18F]FPBM for PET imaging of serotonin transporter (SERT) in the brain

    International Nuclear Information System (INIS)

    Qiao, Hongwen; Zhang, Yan; Wu, Zehui; Zhu, Lin; Choi, Seok Rye; Ploessl, Karl; Kung, Hank F.

    2016-01-01

    Serotonin transporters (SERT) in the brain play an important role in normal brain function. Selective serotonin reuptake inhibitors such as fluoxetine, sertraline, paroxetine, escitalopram, etc., specifically target SERT binding in the brain. Development of SERT imaging agents may be useful for studying the function of SERT by in vivo imaging. A one-step preparation of [ 18 F]FPBM, 2-(2′-(dimethylamino)methyl)-4′-(3-([ 18 F]fluoropropoxy)phenylthio) benzenamine, for positron emission tomography (PET) imaging of SERT binding in the brain was achieved. An active OTs intermediate, 9, was reacted with [ 18 F]F − /K 222 to produce [ 18 F]FPBM in one step and in high radiochemical yield. This labeling reaction was evaluated and optimized under different temperatures, bases, solvents, and varying amounts of precursor 9. The radiolabeling reaction led to the desired [ 18 F]FPBM in one step and the crude product was purified by HPLC purification to give no-carrier-added [ 18 F]FPBM (radiochemical yield, 24–33%, decay corrected; radiochemical purity > 99%). PET imaging studies in normal monkeys (n = 4) showed fast, pronounced uptakes in the midbrain and thalamus, regions known to be rich in SERT binding sites. A displacement experiment with escitalopram (5 mg/kg iv injection at 30 min after [ 18 F]FPBM injection) showed a rapid and complete reversal of SERT binding, suggesting that binding by [ 18 F]FPBM was highly specific and reversible. A one-step radiolabeling method coupled with HPLC purification for preparation of [ 18 F]FPBM was developed. Imaging studies suggest that it is feasible to use this method to prepare [ 18 F]FPBM for in vivo PET imaging of SERT binding in the brain.

  9. Thermodynamic assessment of the LiF–ThF4–PuF3–UF4 system

    NARCIS (Netherlands)

    Capelli, E.; Benes, O.; Konings, R.J.M.

    2015-01-01

    The LiF–ThF4–PuF3–UF4 system is the reference salt mixture considered for the Molten Salt Fast Reactor (MSFR) concept started with PuF3. In order to obtain the complete thermodynamic description of this quaternary system, two binary systems (ThF4–PuF3 and UF4–PuF3) and two ternary systems

  10. Time domain localization technique with sparsity constraint for imaging acoustic sources

    Science.gov (United States)

    Padois, Thomas; Doutres, Olivier; Sgard, Franck; Berry, Alain

    2017-09-01

    This paper addresses source localization technique in time domain for broadband acoustic sources. The objective is to accurately and quickly detect the position and amplitude of noise sources in workplaces in order to propose adequate noise control options and prevent workers hearing loss or safety risk. First, the generalized cross correlation associated with a spherical microphone array is used to generate an initial noise source map. Then a linear inverse problem is defined to improve this initial map. Commonly, the linear inverse problem is solved with an l2 -regularization. In this study, two sparsity constraints are used to solve the inverse problem, the orthogonal matching pursuit and the truncated Newton interior-point method. Synthetic data are used to highlight the performances of the technique. High resolution imaging is achieved for various acoustic sources configurations. Moreover, the amplitudes of the acoustic sources are correctly estimated. A comparison of computation times shows that the technique is compatible with quasi real-time generation of noise source maps. Finally, the technique is tested with real data.

  11. Acoustically modulated magnetic resonance imaging of gas-filled protein nanostructures

    Science.gov (United States)

    Lu, George J.; Farhadi, Arash; Szablowski, Jerzy O.; Lee-Gosselin, Audrey; Barnes, Samuel R.; Lakshmanan, Anupama; Bourdeau, Raymond W.; Shapiro, Mikhail G.

    2018-05-01

    Non-invasive biological imaging requires materials capable of interacting with deeply penetrant forms of energy such as magnetic fields and sound waves. Here, we show that gas vesicles (GVs), a unique class of gas-filled protein nanostructures with differential magnetic susceptibility relative to water, can produce robust contrast in magnetic resonance imaging (MRI) at sub-nanomolar concentrations, and that this contrast can be inactivated with ultrasound in situ to enable background-free imaging. We demonstrate this capability in vitro, in cells expressing these nanostructures as genetically encoded reporters, and in three model in vivo scenarios. Genetic variants of GVs, differing in their magnetic or mechanical phenotypes, allow multiplexed imaging using parametric MRI and differential acoustic sensitivity. Additionally, clustering-induced changes in MRI contrast enable the design of dynamic molecular sensors. By coupling the complementary physics of MRI and ultrasound, this nanomaterial gives rise to a distinct modality for molecular imaging with unique advantages and capabilities.

  12. N-(N-benzylpiperidin-4-yl)-2-[{sup 18}F]fluorobenzamide: A potential ligand for PET imaging of {sigma} receptors

    Energy Technology Data Exchange (ETDEWEB)

    Chyngyann, Shiue; Shiue, Grace G; Zhang, Sue X; Wilder, Susan; Greenberg, Joel H; Benard, Francois; Wortman, Jeffrey A; Alavi, Abass A

    1997-10-01

    Four nitro- and fluorobenzamides (1-4) have been synthesized in good yields from nitro- and fluoro-substituted benzoyl chloride with 4-amino-1-benzylpiperidine. In vitro studies showed that these compounds have high affinities to {sigma} receptors. N-(N-Benzylpiperidin-4-yl)-2-fluorobenzamide (3), in particular, bound to {sigma} receptors with high affinity (K{sub i} = 3.4 nM, guinea pig brain membranes) and high selectivity ({sigma}-2/{sigma}-1 = 120). It was, therefore, labeled with {sup 18}F and evaluated as a {sigma} receptor radioligand. N-(N-Benzylpiperidin-4-yl)-2-[{sup 18}F]fluorobenzamide (3a) was synthesized in one step by nucleophilic substitution of the 2-nitro precursor (1) with [{sup 18}F]fluoride in DMSO at 140 deg. C for 20 min followed by purification with HPLC in 4-10% yield (decay corrected). The synthesis time was 90 min and the specific activity was 0.4-1.0 Ci/{mu}mol. Tissue distribution in mice revealed that the uptakes of 3a in the brain, heart, liver, lungs, spleen, kidneys and small intestine were high, and the radioactivity in these organs remained constant from 60 to 120 min post-injection. The radioactivity in the bone did not significantly increase, suggesting in vivo defluorination may not be the major route of metabolism of 3a in mice. Blocking studies with haloperidol in rats indicated that the uptake of compound 3a in the rat brain was selective to haloperidol-sensitive {sigma} sites. These results suggest that compound 3a is a potent {sigma} receptor radioligand and may be a potential ligand for PET imaging of {sigma} receptors in humans.

  13. On the focusing conditions in time-reversed acoustics, seismic interferometry, and Marchenko imaging

    NARCIS (Netherlands)

    Wapenaar, C.P.A.; Van der Neut, J.R.; Thorbecke, J.W.; Vasconcelos, I.; Van Manen, D.J.; Ravasi, M.

    2014-01-01

    Despite the close links between the fields of time-reversed acoustics, seismic interferometry and Marchenko imaging, a number of subtle differences exist. This paper reviews the various focusing conditions of these methods, the causality/acausality aspects of the corresponding focusing wavefields,

  14. 18F-FLT Positron Emission Tomography/Computed Tomography Imaging in Pancreatic Cancer: Determination of Tumor Proliferative Activity and Comparison with Glycolytic Activity as Measured by 18F-FDG Positron Emission Tomography/Computed Tomography Imaging

    Directory of Open Access Journals (Sweden)

    Senait Aknaw Debebe

    2016-02-01

    Full Text Available Objective: This phase-I imaging study examined the imaging characteristic of 3’-deoxy-3’-(18F-fluorothymidine (18F-FLT positron emission tomography (PET in patients with pancreatic cancer and comparisons were made with (18F-fluorodeoxyglucose (18F-FDG. The ultimate aim was to develop a molecular imaging tool that could better define the biologic characteristics of pancreas cancer, and to identify the patients who could potentially benefit from surgical resection who were deemed inoperable by conventional means of staging. Methods: Six patients with newly diagnosed pancreatic cancer underwent a combined FLT and FDG computed tomography (CT PET/CT imaging protocol. The FLT PET/CT scan was performed within 1 week of FDG PET/CT imaging. Tumor uptake of a tracer was determined and compared using various techniques; statistical thresholding (z score=2.5, and fixed standardized uptake value (SUV thresholds of 1.4 and 2.5, and applying a threshold of 40% of maximum SUV (SUVmax and mean SUV (SUVmean. The correlation of functional tumor volumes (FTV between 18F-FDG and 18F-FLT was assessed using linear regression analysis. Results: It was found that there is a correlation in FTV due to metabolic and proliferation activity when using a threshold of SUV 2.5 for FDG and 1.4 for FLT (r=0.698, p=ns, but a better correlation was obtained when using SUV of 2.5 for both tracers (r=0.698, p=ns. The z score thresholding (z=2.5 method showed lower correlation between the FTVs (r=0.698, p=ns of FDG and FLT PET. Conclusion: Different tumor segmentation techniques yielded varying degrees of correlation in FTV between FLT and FDGPET images. FLT imaging may have a different meaning in determining tumor biology and prognosis.

  15. Negative refraction imaging of solid acoustic waves by two-dimensional three-component phononic crystal

    International Nuclear Information System (INIS)

    Li Jing; Liu Zhengyou; Qiu Chunyin

    2008-01-01

    By using of the multiple scattering methods, we study the negative refraction imaging effect of solid acoustic waves by two-dimensional three-component phononic crystals composed of coated solid inclusions placed in solid matrix. We show that localized resonance mechanism brings on a group of flat single-mode bands in low-frequency region, which provides two equivalent frequency surfaces (EFS) close to circular. The two constant frequency surfaces correspond to two Bloch modes, a right-handed and a left-handed, whose leading mode are respectively transverse (T) and longitudinal (L) modes. The negative refraction behaviors of the two kinds of modes have been demonstrated by simulation of a Gaussian beam through a finite system. High-quality far-field imaging by a planar lens for transverse or longitudinal waves has been realized separately. This three-component phononic crystal may thus serve as a mode selector in negative refraction imaging of solid acoustic waves

  16. 18F-FPYBF-2, a new F-18 labelled amyloid imaging PET tracer: biodistribution and radiation dosimetry assessment of first-in-man 18F-FPYBF-2 PET imaging.

    Science.gov (United States)

    Nishii, Ryuichi; Higashi, Tatsuya; Kagawa, Shinya; Okuyama, Chio; Kishibe, Yoshihiko; Takahashi, Masaaki; Okina, Tomoko; Suzuki, Norio; Hasegawa, Hiroshi; Nagahama, Yasuhiro; Ishizu, Koichi; Oishi, Naoya; Kimura, Hiroyuki; Watanabe, Hiroyuki; Ono, Masahiro; Saji, Hideo; Yamauchi, Hiroshi

    2018-05-01

    Recently, a benzofuran derivative for the imaging of β-amyloid plaques, 5-(5-(2-(2-(2- 18 F-fluoroethoxy)ethoxy)ethoxy)benzofuran-2-yl)- N-methylpyridin-2-amine ( 18 F-FPYBF-2) has been validated as a tracer for amyloid imaging and it was found that 18 F-FPYBF-2 PET/CT is a useful and reliable diagnostic tool for the evaluation of AD (Higashi et al. Ann Nucl Med, https://doi.org/10.1007/s12149-018-1236-1 , 2018). The aim of this study was to assess the biodistribution and radiation dosimetry of diagnostic dosages of 18 F-FPYBF-2 in normal healthy volunteers as a first-in-man study. Four normal healthy volunteers (male: 3, female: 1; mean age: 40 ± 17; age range 25-56) were included and underwent 18 F-FPYBF-2 PET/CT study for the evaluation of radiation exposure and pharmacokinetics. A 10-min dynamic PET/CT scan of the body (chest and abdomen) was performed at 0-10 min and a 15-min whole-body static scan was performed six times after the injection of 18 F-FPYBF-2. After reconstructing PET and CT image data, individual organ time-activity curves were estimated by fitting volume of interest data from the dynamic scan and whole-body scans. The OLINDA/EXM version 2.0 software was used to determine the whole-body effective doses. Dynamic PET imaging demonstrated that the hepatobiliary and renal systems were the principal pathways of clearance of 18 F-FPYBF-2. High uptake in the liver and the gall bladder, the stomach, and the kidneys were demonstrated, followed by the intestines and the urinary bladder. The ED for the adult dosimetric model was estimated to be 8.48 ± 1.25 µSv/MBq. The higher absorbed doses were estimated for the liver (28.98 ± 12.49 and 36.21 ± 15.64 µGy/MBq), the brain (20.93 ± 4.56 and 23.05 ± 5.03µ Gy/MBq), the osteogenic cells (9.67 ± 1.67 and 10.29 ± 1.70 µGy/MBq), the small intestines (9.12 ± 2.61 and 11.12 ± 3.15 µGy/MBq), and the kidneys (7.81 ± 2.62 and 8.71 ± 2.90 µGy/MBq) for

  17. 18F-labelled annexin V: a PET tracer for apoptosis imaging

    International Nuclear Information System (INIS)

    Murakami, Yoshihiro; Tatsumi, Mitsuyoshi; Ichise, Rikiya; Nishimura, Shintaro; Takamatsu, Hiroyuki; Noda, Akihiro; Taki, Junichi; Tait, Jonathan F.

    2004-01-01

    Annexin V can be used to detect apoptotic cells in vitro and in vivo, based on its ability to identify extracellular phosphatidylserine, which arises during apoptosis. In the present study, we examined the synthesis of fluorine-18 labelled annexin V as a positron emission tomography tracer for apoptosis imaging. The distribution of [ 18 F]annexin V and technetium-99m labelled annexin V, a well-characterised SPET tracer for apoptosis imaging, was compared. [ 18 F]annexin V was synthesised using N-succinimidyl 4-[ 18 F]fluorobenzoate as an 18 F labelling reagent. Synthesised and purified [ 18 F]annexin V was confirmed by SDS-PAGE. In an ex vivo imaging experiment, [ 18 F]annexin V was intravenously injected into rats 24 h after the induction of myocardial ischaemia, and accumulation in the left ventricle was examined. [ 18 F]annexin V accumulated in the infarct area of the left ventricle, where apoptotic cells were observed. In separate experiments, [ 18 F]annexin V or [ 99m Tc]annexin V was intravenously injected into ischaemic or normal animals, and the distribution of the tracers was compared. In ischaemic animals, accumulation of [ 18 F]annexin V and [ 99m Tc]annexin V in the infarct area was about threefold higher than in the non-infarct area. Furthermore, the ratio of accumulation in the normal heart to the blood radioactivity was not significantly different between the tracers. In normal animals, however, the uptake of [ 18 F]annexin V in the liver, spleen and kidney was much lower than that of [ 99m Tc]annexin V. The low uptake of [ 18 F]annexin V in these organs might represent an advantage over [ 99m Tc]annexin V. (orig.)

  18. Schlieren imaging of the standing wave field in an ultrasonic acoustic levitator

    Science.gov (United States)

    Rendon, Pablo Luis; Boullosa, Ricardo R.; Echeverria, Carlos; Porta, David

    2015-11-01

    We consider a model of a single axis acoustic levitator consisting of two cylinders immersed in air and directed along the same axis. The first cylinder has a flat termination and functions as a sound emitter, and the second cylinder, which is simply a refector, has the side facing the first cylinder cut out by a spherical surface. By making the first cylinder vibrate at ultrasonic frequencies a standing wave is produced in the air between the cylinders which makes it possible, by means of the acoustic radiation pressure, to levitate one or several small objects of different shapes, such as spheres or disks. We use schlieren imaging to observe the acoustic field resulting from the levitation of one or several objects, and compare these results to previous numerical approximations of the field obtained using a finite element method. The authors acknowledge financial support from DGAPA-UNAM through project PAPIIT IN109214.

  19. {sup 18}F-labeled RGD peptide: initial evaluation for imaging brain tumor angiogenesis

    Energy Technology Data Exchange (ETDEWEB)

    Chen Xiaoyuan; Park, Ryan; Shahinian, Anthony H.; Tohme, Michel; Khankaldyyan, Vazgen; Bozorgzadeh, Mohammed H.; Bading, James R.; Moats, Rex; Laug, Walter E.; Conti, Peter S. E-mail: pconti@usc.edu

    2004-02-01

    Brain tumors are highly angiogenesis dependent. The cell adhesion receptor integrin {alpha}{sub v}{beta}{sub 3} is overexpressed in glioma and activated endothelial cells and plays an important role in brain tumor growth, spread and angiogenesis. Suitably labeled {alpha}{sub v}{beta}{sub 3}-integrin antagonists may therefore be useful for imaging brain tumor associated angiogenesis. Cyclic RGD peptide c(RGDyK) was labeled with {sup 18}F via N-succinimidyl-4-[{sup 18}F]fluorobenzoate through the side-chain {epsilon}-amino group of the lysine residue. The radiotracer was evaluated in vivo for its tumor targeting efficacy and pharmacokinetics in subcutaneously implanted U87MG and orthotopically implanted U251T glioblastoma nude mouse models by means of microPET, quantitative autoradiography and direct tissue sampling. The N-4-[{sup 18}F]fluorobenzoyl-RGD ([{sup 18}F]FB-RGD) was produced in less than 2 h with 20-25% decay-corrected yields and specific activity of 230 GBq/{mu}mol at end of synthesis. The tracer showed very rapid blood clearance and both hepatobiliary and renal excretion. Tumor-to-muscle uptake ratio at 30 min was approximately 5 in the subcutaneous U87MG tumor model. MicroPET imaging with the orthotopic U251T brain tumor model revealed very high tumor-to-brain ratio, with virtually no uptake in the normal brain. Successful blocking of tumor uptake of [{sup 18}F]FB-RGD in the presence of excess amount of c(RGDyK) revealed receptor specific activity accumulation. Hence, N-4-[{sup 18}F]fluorobenzoyl labeled cyclic RGD peptide [{sup 18}F]FB-RGD is a potential tracer for imaging {alpha}{sub v}{beta}{sub 3}-integrin positive tumors in brain and other anatomic locations.

  20. Development and validation of a combined phased acoustical radiosity and image source model for predicting sound fields in rooms

    DEFF Research Database (Denmark)

    Marbjerg, Gerd Høy; Brunskog, Jonas; Jeong, Cheol-Ho

    2015-01-01

    A model, combining acoustical radiosity and the image source method, including phase shifts on reflection, has been developed. The model is denoted Phased Acoustical Radiosity and Image Source Method (PARISM), and it has been developed in order to be able to model both specular and diffuse...... radiosity by regarding the model as being stochastic. Three methods of implementation are proposed and investigated, and finally, recommendations are made for their use. Validation of the image source method is done by comparison with finite element simulations of a rectangular room with a porous absorber...

  1. Linear Stability Analysis of an Acoustically Vaporized Droplet

    Science.gov (United States)

    Siddiqui, Junaid; Qamar, Adnan; Samtaney, Ravi

    2015-11-01

    Acoustic droplet vaporization (ADV) is a phase transition phenomena of a superheat liquid (Dodecafluoropentane, C5F12) droplet to a gaseous bubble, instigated by a high-intensity acoustic pulse. This approach was first studied in imaging applications, and applicable in several therapeutic areas such as gas embolotherapy, thrombus dissolution, and drug delivery. High-speed imaging and theoretical modeling of ADV has elucidated several physical aspects, ranging from bubble nucleation to its subsequent growth. Surface instabilities are known to exist and considered responsible for evolving bubble shapes (non-spherical growth, bubble splitting and bubble droplet encapsulation). We present a linear stability analysis of the dynamically evolving interfaces of an acoustically vaporized micro-droplet (liquid A) in an infinite pool of a second liquid (liquid B). We propose a thermal ADV model for the base state. The linear analysis utilizes spherical harmonics (Ynm, of degree m and order n) and under various physical assumptions results in a time-dependent ODE of the perturbed interface amplitudes (one at the vapor/liquid A interface and the other at the liquid A/liquid B interface). The perturbation amplitudes are found to grow exponentially and do not depend on m. Supported by KAUST Baseline Research Funds.

  2. The receptor locus for escherichia coli F4ab/F4ac in the pig maps distal to the MUC4-LMLN region

    DEFF Research Database (Denmark)

    Rampoldi, Antonio; Jacobsen, Mette Juul; Bertschinger, Hans U.

    2011-01-01

    antigenic variants, F4ab, F4ac, and F4ad, of which F4ac is the most common. Resistance to ETEC F4ab/F4ac adhesion in pigs has been shown to be inherited as an autosomal recessive trait. In previous studies the ETEC F4ab/F4ac receptor locus (F4bcR) was mapped to the q41 region on pig chromosome 13....... A polymorphism within an intron of the mucin 4 (MUC4) gene, which is one of the possible candidate genes located in this region, was shown earlier to cosegregate with the F4bcR alleles. Recently, we discovered a Large White boar from a Swiss experimental herd with a recombination between F4bcR and MUC4. A three...... a newly detected SNP in the leishmanolysin-like gene (LMLN g.15920) and SNP ALGA0072075. In this study the six SNPs ALGA0072075, ALGA0106330, MUC13-226, MUC13-813, DIA0000584, and MARC0006918 were in complete linkage disequilibrium with F4bcR. Based on this finding and earlier investigations, we suggest...

  3. Simultaneous functional imaging using fPET and fMRI

    Energy Technology Data Exchange (ETDEWEB)

    Villien, Marjorie [CERMEP (France)

    2015-05-18

    Brain mapping of task-associated changes in metabolism with PET has been accomplished by subtracting scans acquired during two distinct static states. We have demonstrated that PET can provide truly dynamic information on cerebral energy metabolism using constant infusion of FDG and multiple stimuli in a single experiment. We demonstrate here that the functional PET (fPET-FDG) method accomplished simultaneously with fMRI, can enable the first direct comparisons in time, space and magnitude of hemodynamics and oxygen and glucose consumption. The imaging studies were performed on a 3T Tim-Trio MR scanner modified to support an MR-compatible BrainPET insert. Ten healthy subjects were included. The total PET acquisition and infusion time was 90 minutes. We did 3 blocks of right hand fingers tapping for 10 minutes at 30, 50 and 70 minutes after the beginning of the PET acquisition. ASL and BOLD imaging were acquired simultaneously during the motor paradigm. Changes in glucose utilization are easily observed as changes in the TAC slope of the PET data (FDG utilization rate) and in the derivative signal during motor stimuli in the activated voxels. PET and MRI (ASL, and BOLD) activations are largely colocalized but with very different statistical significance and temporal dynamic, especially in the ipsilateral side of the stimuli. This study demonstrated that motor activation can be measured dynamically during a single FDG PET scan. The complementary nature of fPET-FDG to fMRI capitalizes on the emerging technology of hybrid MR-PET scanners. fPET-FDG, combined with quantitative fMRI methods, allow us to simultaneously measure dynamic changes in glucose utilization and hemodynamic, addressing vital questions about neurovascular coupling.

  4. Simultaneous functional imaging using fPET and fMRI

    International Nuclear Information System (INIS)

    Villien, Marjorie

    2015-01-01

    Brain mapping of task-associated changes in metabolism with PET has been accomplished by subtracting scans acquired during two distinct static states. We have demonstrated that PET can provide truly dynamic information on cerebral energy metabolism using constant infusion of FDG and multiple stimuli in a single experiment. We demonstrate here that the functional PET (fPET-FDG) method accomplished simultaneously with fMRI, can enable the first direct comparisons in time, space and magnitude of hemodynamics and oxygen and glucose consumption. The imaging studies were performed on a 3T Tim-Trio MR scanner modified to support an MR-compatible BrainPET insert. Ten healthy subjects were included. The total PET acquisition and infusion time was 90 minutes. We did 3 blocks of right hand fingers tapping for 10 minutes at 30, 50 and 70 minutes after the beginning of the PET acquisition. ASL and BOLD imaging were acquired simultaneously during the motor paradigm. Changes in glucose utilization are easily observed as changes in the TAC slope of the PET data (FDG utilization rate) and in the derivative signal during motor stimuli in the activated voxels. PET and MRI (ASL, and BOLD) activations are largely colocalized but with very different statistical significance and temporal dynamic, especially in the ipsilateral side of the stimuli. This study demonstrated that motor activation can be measured dynamically during a single FDG PET scan. The complementary nature of fPET-FDG to fMRI capitalizes on the emerging technology of hybrid MR-PET scanners. fPET-FDG, combined with quantitative fMRI methods, allow us to simultaneously measure dynamic changes in glucose utilization and hemodynamic, addressing vital questions about neurovascular coupling.

  5. Nicotinic {alpha}4{beta}2 receptor imaging agents

    Energy Technology Data Exchange (ETDEWEB)

    Pichika, Rama [Brain Imaging Center, Department of Psychiatry and Human Behavior, University of California, Irvine, CA 92697-3960 (United States); Easwaramoorthy, Balasubramaniam [Brain Imaging Center, Department of Psychiatry and Human Behavior, University of California, Irvine, CA 92697-3960 (United States); Collins, Daphne [Brain Imaging Center, Department of Psychiatry and Human Behavior, University of California, Irvine, CA 92697-3960 (United States); Christian, Bradley T. [Department of Nuclear Medicine, Kettering Medical Center, Dayton, OH 45429 (United States); Shi, Bingzhi [Department of Nuclear Medicine, Kettering Medical Center, Dayton, OH 45429 (United States); Narayanan, Tanjore K. [Department of Nuclear Medicine, Kettering Medical Center, Dayton, OH 45429 (United States); Potkin, Steven G. [Brain Imaging Center, Department of Psychiatry and Human Behavior, University of California, Irvine, CA 92697-3960 (United States); Mukherjee, Jogeshwar [Brain Imaging Center, Department of Psychiatry and Human Behavior, University of California, Irvine, CA 92697-3960 (United States)]. E-mail: j.mukherjee@uci.edu

    2006-04-15

    The {alpha}4{beta}2 nicotinic acetylcholine receptor (nAChR) has been implicated in various neurodegenerative diseases. Optimal positron emission tomography (PET) imaging agents are therefore highly desired for this receptor. We report here the development and initial evaluation of 2-fluoro-3-[2-((S)-3-pyrrolinyl)methoxy]pyridine (nifene). In vitro binding affinity of nifene in rat brain homogenate using {sup 3}H-cytisine exhibited a K {sub i}=0.50 nM for the {alpha}4{beta}2 sites. The radiosynthesis of 2-{sup 18}F-fluoro-3-[2-((S)-3-pyrrolinyl)methoxy]pyridine ({sup 18}F-nifene) was accomplished in 2.5 h with an overall radiochemical yield of 40-50%, decay corrected. The specific activity was estimated to be approx. 37-185 GBq/{mu}mol. In vitro autoradiography in rat brain slices indicated selective binding of {sup 18}F-nifene to anteroventral thalamic (AVT) nucleus, thalamus, subiculum, striata, cortex and other regions consistent with {alpha}4{beta}2 receptor distribution. Rat cerebellum showed some binding, whereas regions in the hippocampus had the lowest binding. The highest ratio of >13 between AVT and cerebellum was measured for {sup 18}F-nifene in rat brain slices. The specific binding was reduced (>95%) by 300 {mu}M nicotine in these brain regions. Positron emission tomography imaging study of {sup 18}F-nifene (130 MBq) in anesthetized rhesus monkey was carried out using an ECAT EXACT HR+ scanner. PET study showed selective maximal uptake in the regions of the anterior medial thalamus, ventro-lateral thalamus, lateral geniculate, cingulate gyrus, temporal cortex including the subiculum. The cerebellum in the monkeys showed lower binding than the other regions. Thalamus-to-cerebellum ratio peaked at 30-35 min postinjection to a value of 2.2 and subsequently reduced. The faster binding profile of {sup 18}F-nifene indicates promise as a PET imaging agent and thus needs further evaluation.

  6. Effect of MRI acoustic noise on cerebral fludeoxyglucose uptake in simultaneous MR-PET imaging.

    Science.gov (United States)

    Chonde, Daniel B; Abolmaali, Nasreddin; Arabasz, Grae; Guimaraes, Alexander R; Catana, Ciprian

    2013-05-01

    Integrated scanners capable of simultaneous positron emission tomography (PET) and magnetic resonance imaging (MRI) data acquisition are now available for human use. Although the scanners' manufacturers have made substantial efforts to understand and minimize the mutual electromagnetic interference between the 2 modalities, the potential physiological inference has not been evaluated. In this study, we have studied the influence of the acoustic noise produced by the magnetic resonance (MR) gradients on brain fludeoxyglucose (FDG) uptake in the Siemens MR-BrainPET prototype. Although particular attention was paid to the primary auditory cortex (PAC), a brain-wide analysis was also performed. The effects of the MR on the PET count rate and image quantification were first investigated in phantoms. Next, 10 healthy volunteers underwent 2 simultaneous FDG-PET/MR scans in the supine position with the FDG injection occurring inside the MR-BrainPET, alternating between a "quiet" (control) environment in which no MR sequences were run during the FDG uptake phase (the first 40 minutes after radiotracer administration) and a "noisy" (test) environment in which MR sequences were run for the entire time. Cortical and subcortical regions of interest were derived from the high-resolution morphological MR data using FreeSurfer. The changes in the FDG uptake in the FreeSurfer-derived regions of interest between the 2 conditions were analyzed from parametric and static PET images, and on a voxel-by-voxel basis using SPM8 and FreeSurfer. Only minimal to no electromagnetic interference was observed for most of the MR sequences tested, with a maximum drop in count rate of 1.5% and a maximum change in the measured activity of 1.1% in the corresponding images. The region of interest-based analysis showed statistically significant increases in the right PAC in both the parametric (9.13% [4.73%]) and static (4.18% [2.87%]) images. The SPM8 analysis showed no statistically significant

  7. Parallel feedback active noise control of MRI acoustic noise with signal decomposition using hybrid RLS-NLMS adaptive algorithms.

    Science.gov (United States)

    Ganguly, Anshuman; Krishna Vemuri, Sri Hari; Panahi, Issa

    2014-01-01

    This paper presents a cost-effective adaptive feedback Active Noise Control (FANC) method for controlling functional Magnetic Resonance Imaging (fMRI) acoustic noise by decomposing it into dominant periodic components and residual random components. Periodicity of fMRI acoustic noise is exploited by using linear prediction (LP) filtering to achieve signal decomposition. A hybrid combination of adaptive filters-Recursive Least Squares (RLS) and Normalized Least Mean Squares (NLMS) are then used to effectively control each component separately. Performance of the proposed FANC system is analyzed and Noise attenuation levels (NAL) up to 32.27 dB obtained by simulation are presented which confirm the effectiveness of the proposed FANC method.

  8. Acoustic Characterization and Enhanced Ultrasound Imaging of Long-Circulating Lipid-Coated Microbubbles.

    Science.gov (United States)

    Li, Hongbo; Yang, Yanye; Zhang, Meimei; Yin, Liping; Tu, Juan; Guo, Xiasheng; Zhang, Dong

    2018-05-01

    A long-circulating lipid-coated ultrasound (US) contrast agent was fabricated to achieve a longer wash-out time and gain more resistance against higher-mechanical index sonication. Systemic physical, acoustic, and in vivo imaging experiments were performed to better understand the underlying mechanism enabling the improvement of contrast agent performance by adjusting the physical and acoustic properties of contrast agent microbubbles. By simply altering the gas core, a kind of US contrast agent microbubble was synthesized with a similar lipid-coating shell as SonoVue microbubbles (Bracco SpA, Milan, Italy) to achieve a longer wash-out time and higher inertial cavitation threshold. To bridge the structure-performance relationship of the synthesized microbubbles, the imaging performance of the microbubbles was assessed in vivo with SonoVue as a control group. The size distribution and inertial cavitation threshold of the synthesized microbubbles were characterized, and the shell parameters of the microbubbles were determined by acoustic attenuation measurements. All of the measurements were compared with SonoVue microbubbles. The synthesized microbubbles had a spherical shape, a smooth, consistent membrane, and a uniform distribution, with an average diameter of 1.484 μm. According to the measured attenuation curve, the synthesized microbubbles resonated at around 2.8 MHz. Although the bubble's shell elasticity (0.2 ± 0.09 N/m) was comparable with SonoVue, it had relatively greater viscosity and inertial cavitation because of the different gas core. Imaging studies showed that the synthesized microbubbles had a longer circulation time and a better chance of fighting against rapid collapse than SonoVue. Nano/micrometer long-circulating lipid-coated microbubbles could be fabricated by simply altering the core composition of SonoVue microbubbles with a higher-molecular weight gas. The smaller diameter and higher inertial cavitation threshold of the

  9. Hypoxia imaging of uterine cervix carcinoma with (18)F-FETNIM PET/CT.

    Science.gov (United States)

    Vercellino, Laetitia; Groheux, David; Thoury, Anne; Delord, Marc; Schlageter, Marie-Hélène; Delpech, Yann; Barré, Emmanuelle; Baruch-Hennequin, Valérie; Tylski, Perrine; Homyrda, Laurence; Walker, Francine; Barranger, Emmanuel; Hindié, Elif

    2012-11-01

    Our aims were to assess the feasibility of imaging hypoxia in cervical carcinoma with (18)F-fluoroerythronitroimidazole ((18)F-FETNIM) and to compare (18)F-FETNIM uptake with metabolic uptake of (18)F-FDG. We included 16 patients with cervical carcinoma. After imaging with FDG, (18)F-FETNIM PET/CT was performed and tumor-to-muscle (T/M) ratio uptake was assessed. (18)F- FETNIM uptake was correlated to FDG uptake and osteopontin (OPN), a marker of hypoxia, and patients' outcomes. All tumors were detected by (18)F-FDG PET. (18)F-FETNIM T/M ratios ranged from 1.3 to 5.4. There was no significant correlation between (18)F-FETNIM and (18)F-FDG uptake. High (18)F-FETNIM uptake (T/M > 3.2) was associated with reduced progression-free survival (log-rank = 0.002) and overall survival (log-rank = 0.02). Osteopontin ranged from 39 to 662 μg/L (median, 102.5 μg/L). Patients with OPN greater than 144 μg/L had reduced progression-free survival compared with those with OPN less than 144 μg/L (log-rank = 0.03). We found no significant correlation between (18)F-FETNIM uptake and OPN blood levels. Our preliminary results showed that a high uptake of (18)F-FETNIM was associated with a worse progression-free and overall survival.

  10. Recognition of fibrous dysplasia of bone mimicking skeletal metastasis on 18F-FDG PET/CT imaging

    International Nuclear Information System (INIS)

    Su, Ming Gang; Tian, Rong; Fan, Qiu Ping; Tian, Ye; Li, Fang Lan; Li, Lin; Kuang, An Ren; Miller, John Howard

    2011-01-01

    Fibrous dysplasia of bone (FDB) reveals intense 18F-FDG uptake mimicking metastases on 18F-FDG PET/CT. We reviewed sites of FDB revealed by 18F-FDG PET/CT imaging to allow identification of this abnormality. Eleven patients (7 male, 4 female, aged 16-78 years) were evaluated after 55 MBq (0.15 mCi)/kg 18F-FDG utilizing a 16-slice multiple detector CT (MDCT) whole-body PET scanner, with LOR algorithm 3D reconstruction. One- and 2-h imaging was performed in 9 patients. Standard uptake value (SUV) for each lesion, on early and delayed imaging, was calculated. Lesions were confirmed in 6 patients by biopsy. The PET images correlated with MDCT to establish the imaging characteristics. Solitary lesions were found in 4 patients, two lesions in 1 patient, and in 6 patients there were multiple bone lesions. The SUV early ranged from 1.23 to 9.64 with an average of 3.76 ± 2.40. The SUV delayed ranged from 1.76 to 11.42 with an average of 4.51 ± 3.07. The SUV delayed decreased or increased slightly (-31% to 5%) in 6 of our patients, and increased significantly (11% to 39%) in 3. There was a negative correlation between SUVs and age, as well as the number of affected bones. In our study, FDB had wide skeletal distribution with variability of 18F-FDG uptake and CT appearance. SUV in the delayed stage was seen to either decrease or increase on dual-time 18F-FDG PET scanning. It is very important to recognize the characteristics of this skeletal dysplasia to allow differentiation from skeletal metastasis. (orig.)

  11. TU-AB-BRA-05: Repeatability of [F-18]-NaF PET Imaging Biomarkers for Bone Lesions: A Multicenter Study

    International Nuclear Information System (INIS)

    Lin, C; Bradshaw, T; Perk, T; Harmon, S; Jeraj, R; Liu, G

    2015-01-01

    Purpose: Quantifying the repeatability of imaging biomarkers is critical for assessing therapeutic response. While therapeutic efficacy has been traditionally quantified by SUV metrics, imaging texture features have shown potential for use as quantitative biomarkers. In this study we evaluated the repeatability of quantitative "1"8F-NaF PET-derived SUV metrics and texture features in bone lesions from patients in a multicenter study. Methods: Twenty-nine metastatic castrate-resistant prostate cancer patients received whole-body test-retest NaF PET/CT scans from one of three harmonized imaging centers. Bone lesions of volume greater than 1.5 cm"3 were identified and automatically segmented using a SUV>15 threshold. From each lesion, 55 NaF PET-derived texture features (including first-order, co-occurrence, grey-level run-length, neighbor gray-level, and neighbor gray-tone difference matrix) were extracted. The test-retest repeatability of each SUV metric and texture feature was assessed with Bland-Altman analysis. Results: A total of 315 bone lesions were evaluated. Of the traditional SUV metrics, the repeatability coefficient (RC) was 12.6 SUV for SUVmax, 2.5 SUV for SUVmean, and 4.3 cm"3 for volume. Their respective intralesion coefficients of variation (COVs) were 12%, 17%, and 6%. Of the texture features, COV was lowest for entropy (0.03%) and highest for kurtosis (105%). Lesion intraclass correlation coefficient (ICC) was lowest for maximum correlation coefficient (ICC=0.848), and highest for entropy (ICC=0.985). Across imaging centers, repeatability of texture features and SUV varied. For example, across imaging centers, COV for SUVmax ranged between 11–23%. Conclusion: Many NaF PET-derived SUV metrics and texture features for bone lesions demonstrated high repeatability, such as SUVmax, entropy, and volume. Several imaging texture features demonstrated poor repeatability, such as SUVtotal and SUVstd. These results can be used to establish response criteria

  12. Utility of [18F]FSPG PET to Image Hepatocellular Carcinoma: First Clinical Evaluation in a US Population.

    Science.gov (United States)

    Kavanaugh, Gina; Williams, Jason; Morris, Andrew Scott; Nickels, Michael L; Walker, Ronald; Koglin, Norman; Stephens, Andrew W; Washington, M Kay; Geevarghese, Sunil K; Liu, Qi; Ayers, Dan; Shyr, Yu; Manning, H Charles

    2016-12-01

    Non-invasive imaging is central to hepatocellular carcinoma (HCC) diagnosis; however, conventional modalities are limited by smaller tumors and other chronic diseases that are often present in patients with HCC, such as cirrhosis. This pilot study evaluated the feasibility of (4S)-4-(3-[ 18 F]fluoropropyl)-L-glutamic acid ([ 18 F]FSPG) positron emission tomography (PET)/X-ray computed tomography (CT) to image HCC. [ 18 F]FSPG PET/CT was compared to standard-of-care (SOC) magnetic resonance imaging (MRI) and CT, and [ 11 C]acetate PET/CT, commonly used in this setting. We report the largest cohort of HCC patients imaged to date with [ 18 F]FSPG PET/CT and present the first comparison to [ 11 C]acetate PET/CT and SOC imaging. This study represents the first in a US HCC population, which is distinguished by different underlying comorbidities than non-US populations. x C- transporter RNA and protein levels were evaluated in HCC and matched liver samples from The Cancer Genome Atlas (n = 16) and a tissue microarray (n = 83). Eleven HCC patients who underwent prior MRI or CT scans were imaged by [ 18 F]FSPG PET/CT, with seven patients also imaged with [ 11 C]acetate PET/CT. x C- transporter RNA and protein levels were elevated in HCC samples compared to background liver. Over 50 % of low-grade HCCs and ~70 % of high-grade tumors exceeded background liver protein expression. [ 18 F]FSPG PET/CT demonstrated a detection rate of 75 %. [ 18 F]FSPG PET/CT also identified an HCC devoid of typical MRI enhancement pattern. Patients scanned with [ 18 F]FSPG and [ 11 C]acetate PET/CT exhibited a 90 and 70 % detection rate, respectively. In dually positive tumors, [ 18 F]FSPG accumulation consistently resulted in significantly greater tumor-to-liver background ratios compared with [ 11 C]acetate PET/CT. [ 18 F]FSPG PET/CT is a promising modality for HCC imaging, and larger studies are warranted to examine [ 18 F]FSPG PET/CT impact on diagnosis and management of HCC. [ 18 F

  13. Synthesis and kinetics of [18F]4'-fluoroantipyrine in normal mice

    International Nuclear Information System (INIS)

    Robbins, P.J.; Fortman, D.L.; Scholz, K.L.; Fusaro, G.A.; Sodd, V.J.

    1978-01-01

    Antipyrine labeled with radioiodine has proven useful for studying the symmetry of human brain perfusion by gamma-camera techniques. The feasibility of preparing F-18-labeled antipyrine for eventual use with a positron camera was investigated. The preparation of [ 18 F] 4'-fluoroantipyrine and its distribution in normal mice were used to evaluate this potential. 4'-Fluoroantipyrine was prepared in 7 to 20% chemical yield by the pyrolysis of the 4'-diazonium fluoroborate salt of antipyrine. This Schiemann salt was prepared by a five-step synthesis from 1-(4'-nitrophenyl)-3-methyl-5-chloro-pyrazole. Fluorine-18 labeling of the diazonium fluoroborate salt by exchange with aqueous F-18 and pyrolysis of the dried labeled salt produced [ 18 F] 4'-fluoroantipyrine with specific activities of 0.83 to 2.7 μCi/mg. The incorporated F-18 activity ranged from 0.53 to 1.9%. The labeling procedure took about 3 hr. The labeled antipyrine was administered by tail vein to fasting female Swiss-Cox mice. Distribution of F-18 at 12, 30, 60, and 120 sec, and 10 min, after injection showed that radioactivity persisted in the brain up to 120 sec at a level greater than that of the skin and the bone. (Skin and bone samples were chosen as representative of activities in the scalp and skull surrounding the brain.) Thus, perfusion imaging of the CNS should be possible when greater quantities of high-specific-activity F-18-labeled antipyrine becomes available

  14. Velocity map imaging of ion-molecule reaction products: Co+(3F4)+isobutane

    Science.gov (United States)

    Reichert, Emily L.; Thurau, Gert; Weisshaar, James C.

    2002-07-01

    The velocity map imaging technique is applied to mass-selected CoC3H6++CH4 and CoC4H8++H2 elimination products from the Co+(3F4)+isobutane reaction studied under crossed-beam conditions at 0.21 eV collision energy. For both reactions we obtain the joint scattering probability distribution P(E,Θ), where E and Θ are the product translational energy and scattering angle. The fraction of available energy deposited into product translation is 0.4 for H2, compared with 0.1 for CH4. For the CH4 product, the angular distribution is forward-backwards symmetric and sharply peaked at Θ=0 and 180°. P(E,Θ) is not separable into the product of an energy and an angular function; rather, the angular distribution peaks more sharply at higher translational energy. Evidently, incipient CoC3H6++CH4 products equilibrate in the Co+(C3H6)(CH4) exit-channel well, from which they decay statistically. The product translational energy distribution P(E) is consistent with orbiting-transition state phase-space theory with no exit-channel barrier. In addition, the energy-integrated angular distribution T(Θ) is consistent with the predictions of the early statistical complex decay model of Miller and Herschbach for fragmentation from a transition state that is a prolate top. In sharp contrast, P(E) for the CoC4H8++H2 products exhibits a substantial hot, nonstatistical tail towards high energy. Perhaps the H2 channel has a late potential energy barrier some 0.5 eV above products, but we view this explanation as highly unlikely. Instead, we suggest that the potential energy from an earlier multicenter transition state is funneled efficiently, and highly nonstatistically, into product translation. This surprising conclusion may apply to H2 products for the entire family of reactions of the late-3D series transition metal cations Fe+, Co+, and Ni+ with alkanes.

  15. Fiber-optic system for dual-modality imaging of glucose probes 18F-FDG and 6-NBDG in atherosclerotic plaques.

    Directory of Open Access Journals (Sweden)

    Raiyan T Zaman

    Full Text Available Atherosclerosis is a progressive inflammatory condition that underlies coronary artery disease (CAD-the leading cause of death in the United States. Thus, the ultimate goal of this research is to advance our understanding of human CAD by improving the characterization of metabolically active vulnerable plaques within the coronary arteries using a novel catheter-based imaging system. The aims of this study include (1 developing a novel fiber-optic imaging system with a scintillator to detect both 18F and fluorescent glucose probes, and (2 validating the system on ex vivo murine plaques.A novel design implements a flexible fiber-optic catheter consisting of both a radio-luminescence and a fluorescence imaging system to detect radionuclide 18F-fluorodeoxyglucose (18F-FDG and the fluorescent analog 6-(N-(7-Nitrobenz-2-oxa-1,3-diazol-4-ylamino-6-Deoxyglucose (6-NBDG, respectively. Murine macrophage-rich atherosclerotic carotid plaques were imaged ex vivo after intravenous delivery of 18F-FDG or 6-NBDG. Confirmatory optical imaging by IVIS-200 and autoradiography were also performed.Our fiber-optic imaging system successfully visualized both 18F-FDG and 6-NBDG probes in atherosclerotic plaques. For 18F-FDG, the ligated left carotid arteries (LCs exhibited 4.9-fold higher radioluminescence signal intensity compared to the non-ligated right carotid arteries (RCs (2.6 × 10(4 ± 1.4 × 10(3 vs. 5.4 × 10(3 ± 1.3 × 10(3 A.U., P = 0.008. Similarly, for 6-NBDG, the ligated LCs emitted 4.3-fold brighter fluorescent signals than the control RCs (1.6 × 10(2 ± 2.7 × 10(1 vs. 3.8 × 10(1 ± 5.9 A.U., P = 0.002. The higher uptake of both 18F-FDG and 6-NBDG in ligated LCs were confirmed with the IVIS-200 system. Autoradiography further verified the higher uptake of 18F-FDG by the LCs.This novel fiber-optic imaging system was sensitive to both radionuclide and fluorescent glucose probes taken up by murine atherosclerotic plaques. In addition, 6-NBDG is a

  16. F4+ ETEC infection and oral immunization with F4 fimbriae elicits an IL-17-dominated immune response.

    Science.gov (United States)

    Luo, Yu; Van Nguyen, Ut; de la Fe Rodriguez, Pedro Y; Devriendt, Bert; Cox, Eric

    2015-10-21

    Enterotoxigenic Escherichia coli (ETEC) are an important cause of post-weaning diarrhea (PWD) in piglets. Porcine-specific ETEC strains possess different fimbrial subtypes of which F4 fimbriae are the most frequently associated with ETEC-induced diarrhea in piglets. These F4 fimbriae are potent oral immunogens that induce protective F4-specific IgA antibody secreting cells at intestinal tissues. Recently, T-helper 17 (Th17) cells have been implicated in the protection of the host against extracellular pathogens. However, it remains unknown if Th17 effector responses are needed to clear ETEC infections. In the present study, we aimed to elucidate if ETEC elicits a Th17 response in piglets and if F4 fimbriae trigger a similar response. F4(+) ETEC infection upregulated IL-17A, IL-17F, IL-21 and IL-23p19, but not IL-12 and IFN-γ mRNA expression in the systemic and mucosal immune system. Similarly, oral immunization with F4 fimbriae triggered a Th17 signature evidenced by an upregulated mRNA expression of IL-17F, RORγt, IL-23p19 and IL-21 in the peripheral blood mononuclear cells (PBMCs). Intriguingly, IL-17A mRNA levels were unaltered. To further evaluate this difference between systemic and mucosal immune responses, we assayed the cytokine mRNA profile of F4 fimbriae stimulated PBMCs. F4 fimbriae induced IL-17A, IL-17F, IL-22 and IL-23p19, but downregulated IL-17B mRNA expression. Altogether, these data indicate a Th17 dominated response upon oral immunization with F4 fimbriae and F4(+) ETEC infection. Our work also highlights that IL-17B and IL-17F participate in the immune response to protect the host against F4(+) ETEC infection and could aid in the design of future ETEC vaccines.

  17. Molecular beam electric deflection of the tetrahalides CF4, CCl4, SiF4, SiCl4, GeCl4, TiF4, TiCl4, VF4, and VCl4

    International Nuclear Information System (INIS)

    Muenter, A.A.; Dyke, T.R.; Falconer, W.E.; Klemperer, W.

    1975-01-01

    Using molecular beam electric deflection, the temperature dependence of polar behavior has been studied for the molecules CF 4 , CCl 4 , SiF 4 , SiCl 4 , GeCl 4 , TiF 4 TiCl 4 , VF 4 , VF 4 , and VCl 4 . A number of these molecules show polar behavior consistent with a vibrationally induced dipole moment for states with one or both of the triply degenerate vibrations excited. In four of the tetrachloride species, the presence of a vibrationally induced dipole moment was confirmed by the change in polar behavior with isotopic substituion of the Cl atoms. The deflection behavior of the transition metal tetrahalides varied from nonpolar in VCl 4 to very polar in TiF 4

  18. Fluorine-18 NaF PET imaging of child abuse

    Energy Technology Data Exchange (ETDEWEB)

    Drubach, Laura A. [Children' s Hospital Boston and Harvard Medical School, Department of Radiology, Division of Nuclear Medicine/PET, Boston, MA (United States); Sapp, Mark.V. [School of Osteopathic Medicine, Child Abuse Research Education and Services (CARES) Institute University of Medicine and Dentistry of New Jersey, New Jersey (United States); Laffin, Stephen [Children' s Hospital Boston, Department of Radiology, Division of Nuclear Medicine/PET, Boston, MA (United States); Kleinman, Paul K. [Children' s Hospital Boston and Harvard Medical School, Department of Radiology, Division of Musculoskeletal Imaging, Boston, MA (United States)

    2008-07-15

    We describe the use of {sup 18}F-NaF positron emission tomography (PET) whole-body imaging for the evaluation of skeletal trauma in a case of suspected child abuse. To our knowledge, 18F NaF PET has not been used in the past for the evaluation of child abuse. In our patient, this technique detected all sites of trauma shown by initial and follow-up skeletal surveys, including bilateral metaphyseal fractures of the proximal humeri. Fluorine-18 NaF PET has potential advantage over Tc-99m-labeled methylene diphosphonate (MDP) based upon superior image contrast and spatial resolution. (orig.)

  19. Fluorine-18 NaF PET imaging of child abuse

    International Nuclear Information System (INIS)

    Drubach, Laura A.; Sapp, Mark V.; Laffin, Stephen; Kleinman, Paul K.

    2008-01-01

    We describe the use of 18 F-NaF positron emission tomography (PET) whole-body imaging for the evaluation of skeletal trauma in a case of suspected child abuse. To our knowledge, 18F NaF PET has not been used in the past for the evaluation of child abuse. In our patient, this technique detected all sites of trauma shown by initial and follow-up skeletal surveys, including bilateral metaphyseal fractures of the proximal humeri. Fluorine-18 NaF PET has potential advantage over Tc-99m-labeled methylene diphosphonate (MDP) based upon superior image contrast and spatial resolution. (orig.)

  20. Longitudinal imaging of Alzheimer pathology using [11C]PIB, [18F]FDDNP and [18F]FDG PET

    International Nuclear Information System (INIS)

    Ossenkoppele, Rik; Tolboom, Nelleke; Adriaanse, Sofie F.; Foster-Dingley, Jessica C.; Boellaard, Ronald; Yaqub, Maqsood; Windhorst, Albert D.; Lammertsma, Adriaan A.; Berckel, Bart N.M. van; Barkhof, Frederik; Scheltens, Philip; Flier, Wiesje M. van der

    2012-01-01

    [ 11 C]PIB and [ 18 F]FDDNP are PET tracers for in vivo detection of the neuropathology underlying Alzheimer's disease (AD). [ 18 F]FDG is a glucose analogue and its uptake reflects metabolic activity. The purpose of this study was to examine longitudinal changes in these tracers in patients with AD or mild cognitive impairment (MCI) and in healthy controls. Longitudinal, paired, dynamic [ 11 C]PIB and [ 18 F]FDDNP (90 min each) and static [ 18 F]FDG (15 min) PET scans were obtained in 11 controls, 12 MCI patients and 8 AD patients. The mean interval between baseline and follow-up was 2.5 years (range 2.0-4.0 years). Parametric [ 11 C]PIB and [ 18 F]FDDNP images of binding potential (BP ND ) and [ 18 F]FDG standardized uptake value ratio (SUVr) images were generated. A significant increase in global cortical [ 11 C]PIB BP ND was found in MCI patients, but no changes were observed in AD patients or controls. Subsequent regional analysis revealed that this increase in [ 11 C]PIB BP ND in MCI patients was most prominent in the lateral temporal lobe (p 18 F]FDDNP, no changes in global BP ND were found. [ 18 F]FDG uptake was reduced at follow-up in the AD group only, especially in frontal, parietal and lateral temporal lobes (all p 11 C]PIB binding (ρ = -0.42, p 18 F]FDG uptake (ρ = 0.54, p 18 F]FDDNP binding (ρ = -0.18, p = 0.35) were not. [ 11 C]PIB and [ 18 F]FDG track molecular changes in different stages of AD. We found increased amyloid load in MCI patients and progressive metabolic impairment in AD patients. [ 18 F]FDDNP seems to be less useful for examining disease progression. (orig.)

  1. Refined localization of the Escherichia coli F4ab/F4ac receptor locus on pig chromosome 13

    DEFF Research Database (Denmark)

    Joller, D.; Jørgensen, Claus Bøttcher; Bertschinger, H.U.

    2009-01-01

    Diarrhoea in newborn and weaned pigs caused by enterotoxigenic Escherichia coli (ETEC) expressing F4 fimbriae leads to considerable losses in pig production. In this study, we refined the mapping of the receptor locus for ETEC F4ab/F4ac adhesion (F4bcR) by joint analysis of Nordic and Swiss data...... (MUC4-8227) were used to create the linkage map. The region for F4bcR was refined to the interval SW207-S0075 on pig chromosome 13. The most probable position of F4bcR was in the SW207-MUC4 region. The order of six markers was supported by physical mapping on the BAC fingerprint contig from...

  2. Thoracic staging in lung cancer: prospective comparison of 18F-FDG PET/MR imaging and 18F-FDG PET/CT.

    Science.gov (United States)

    Heusch, Philipp; Buchbender, Christian; Köhler, Jens; Nensa, Felix; Gauler, Thomas; Gomez, Benedikt; Reis, Henning; Stamatis, Georgios; Kühl, Hilmar; Hartung, Verena; Heusner, Till A

    2014-03-01

    Therapeutic decisions in non-small cell lung cancer (NSCLC) patients depend on the tumor stage. PET/CT with (18)F-FDG is widely accepted as the diagnostic standard of care. The purpose of this study was to compare a dedicated pulmonary (18)F-FDG PET/MR imaging protocol with (18)F-FDG PET/CT for primary and locoregional lymph node staging in NSCLC patients using histopathology as the reference. Twenty-two patients (12 men, 10 women; mean age ± SD, 65.1 ± 9.1 y) with histopathologically confirmed NSCLC underwent (18)F-FDG PET/CT, followed by (18)F-FDG PET/MR imaging, including a dedicated pulmonary MR imaging protocol. T and N staging according to the seventh edition of the American Joint Committee on Cancer staging manual was performed by 2 readers in separate sessions for (18)F-FDG PET/CT and PET/MR imaging, respectively. Results from histopathology were used as the standard of reference. The mean and maximum standardized uptake value (SUV(mean) and SUV(max), respectively) and maximum diameter of the primary tumor was measured and compared in (18)F-FDG PET/CT and PET/MR imaging. PET/MR imaging and (18)F-FDG PET/CT agreed on T stages in 16 of 16 of patients (100%). All patients were correctly staged by (18)F-FDG PET/CT and PET/MR (100%), compared with histopathology. There was no statistically significant difference between (18)F-FDG PET/CT and (18)F-FDG PET/MR imaging for lymph node metastases detection (P = 0.48). For definition of thoracic N stages, PET/MR imaging and (18)F-FDG PET/CT were concordant in 20 of 22 patients (91%). PET/MR imaging determined the N stage correctly in 20 of 22 patients (91%). (18)F-FDG PET/CT determined the N stage correctly in 18 of 22 patients (82%). The mean differences for SUV(mean) and SUV(max) of NSCLC in (18)F-FDG PET/MR imaging and (18)F-FDG PET/CT were 0.21 and -5.06. These differences were not statistically significant (P > 0.05). The SUV(mean) and SUV(max) measurements derived from (18)F-FDG PET/CT and (18)F-FDG PET

  3. Effect of MRI Acoustic Noise on Cerebral FDG Uptake in Simultaneous MR-PET Imaging

    Science.gov (United States)

    Abolmaali, Nasreddin; Arabasz, Grae; Guimaraes, Alexander R.; Catana, Ciprian

    2013-01-01

    Integrated scanners capable of simultaneous PET and MRI data acquisition are now available for human use. Although the scanners’ manufacturers have made substantial efforts to understand and minimize the mutual electromagnetic interference between the two modalities, the potential physiological inference has not been evaluated. In this work, we have studied the influence of the acoustic noise produced by the MR gradients on brain FDG uptake in the Siemens MR-BrainPET prototype. While particular attention was paid to the primary auditory cortex (PAC), a brain-wide analysis was also performed. Methods The effects of the MR on the PET count rate and image quantification were first investigated in phantoms. Next, ten healthy volunteers underwent two simultaneous FDG-PET/MR scans in the supine position with the FDG injection occurring inside the MR-BrainPET, alternating between a “quiet” (control) environment in which no MR sequences were run during the FDG uptake phase (the first 40 minutes after radiotracer administration) and a “noisy” (test) case in which MR sequences were run for the entire time. Cortical and subcortical regions of interest (ROIs) were derived from the high-resolution morphological MR data using FreeSurfer. The changes in FDG uptake in the FreeSurfer-derived ROIs between the two conditions were analyzed from parametric and static PET images, and on a voxel-by-voxel basis using SPM8 and FreeSurfer. Results Only minimal to no electromagnetic interference was observed for most of the MR sequences tested, with a maximum drop in count rate of 1.5% and a maximum change in the measured activity of 1.1% in the corresponding images. The ROI-based analysis showed statistically significant increases in the right PAC in both the parametric (9.13±4.73%) and static (4.18±2.87%) images. SPM8 analysis showed no statistically significant clusters in any images when a p<0.05 (corrected) was used; however, a p<0.001 (uncorrected) resolved bilateral

  4. Evaluation of TSPO PET Ligands [18F]VUIIS1009A and [18F]VUIIS1009B: Tracers for Cancer Imaging.

    Science.gov (United States)

    Tang, Dewei; Li, Jun; Buck, Jason R; Tantawy, Mohamed Noor; Xia, Yan; Harp, Joel M; Nickels, Michael L; Meiler, Jens; Manning, H Charles

    2017-08-01

    Positron emission tomography (PET) ligands targeting translocator protein (TSPO) are potential imaging diagnostics of cancer. In this study, we report two novel, high-affinity TSPO PET ligands that are 5,7 regioisomers, [ 18 F]VUIIS1009A ([ 18 F]3A) and [ 18 F]VUIIS1009B ([ 18 F]3B), and their initial in vitro and in vivo evaluation in healthy mice and glioma-bearing rats. VUIIS1009A/B was synthesized and confirmed by X-ray crystallography. Interactions between TSPO binding pocket and novel ligands were evaluated and compared with contemporary TSPO ligands using 2D 1 H- 15 N heteronuclear single quantum coherence (HSQC) spectroscopy. In vivo biodistribution of [ 18 F]VUIIS1009A and [ 18 F]VUIIS1009B was carried out in healthy mice with and without radioligand displacement. Dynamic PET imaging data were acquired simultaneously with [ 18 F]VUIIS1009A/B injections in glioma-bearing rats, with binding reversibility and specificity evaluated by radioligand displacement. In vivo radiometabolite analysis was performed using radio-TLC, and quantitative analysis of PET data was performed using metabolite-corrected arterial input functions. Imaging was validated with histology and immunohistochemistry. Both VUIIS1009A (3A) and VUIIS1009B (3B) were found to exhibit exceptional binding affinity to TSPO, with observed IC 50 values against PK11195 approximately 500-fold lower than DPA-714. However, HSQC NMR suggested that VUIIS1009A and VUIIS1009B share a common binding pocket within mammalian TSPO (mTSPO) as DPA-714 and to a lesser extent, PK11195. [ 18 F]VUIIS1009A ([ 18 F]3A) and [ 18 F]VUIIS1009B ([ 18 F]3B) exhibited similar biodistribution in healthy mice. In rats bearing C6 gliomas, both [ 18 F]VUIIS1009A and [ 18 F]VUIIS1009B exhibited greater binding potential (k 3 /k 4 )in tumor tissue compared to [ 18 F]DPA-714. Interestingly, [ 18 F]VUIIS1009B exhibited significantly greater tumor uptake (V T ) than [ 18 F]VUIIS1009A, which was attributed primarily to greater plasma

  5. Preparation and biological evaluation of 2-amino-6-[{sup 18}F]fluoro-9-(4-hydroxy-3-hydroxy-methylbutyl) purine (6-[{sup 18}F]FPCV) as a novel PET probe for imaging HSV1-tk reporter gene expression

    Energy Technology Data Exchange (ETDEWEB)

    Cai Hancheng [Research Center of Radiopharmaceuticals, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800 (China); Graduate School of the Chinese Academy of Sciences, Beijing 100049 (China); Yin Duanzhi [Research Center of Radiopharmaceuticals, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800 (China)], E-mail: chcbati@yahoo.com.cn; Zhang Lan [Research Center of Radiopharmaceuticals, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800 (China); Zhejiang California International NanoSystems Institute, Hangzhou 310029 (China); Yang, Xiaofeng; Xu Xiaoyan; Liu Weiguo; Zheng Xuesheng [Institute of Brain Medical Science, Second affiliated Hospital, Medicine School of Zhejiang University, Hangzhou 310009 (China); Zhang Hong [Department of Nuclear Medicine, Second Affiliated Hospital, Zhejiang University Medical PET Center, Medicine School of Zhejiang University, Hangzhou 310009 (China); Wang Jing [Department of Nuclear Medicine, Second Affiliated Hospital, Zhejiang University Medical PET Center, Medicine School of Zhejiang University, Hangzhou 310009 (China); Zhejiang California International NanoSystems Institute, Hangzhou 310029 (China); Xu Yuhong [Zhejiang California International NanoSystems Institute, Hangzhou 310029 (China); Cheng Dengfeng; Zheng Mingqiang; Han Yanjiang; Wu Mingxing; Wang Yongxian [Research Center of Radiopharmaceuticals, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800 (China)

    2007-08-15

    Introduction: 2-Amino-6-[{sup 18}F]fluoro-9-(4-hydroxy-3-hydroxy-methylbutyl) purine (6-[{sup 18}F]FPCV) was prepared via a one-step nucleophilic substitution and evaluated as a novel probe for imaging the expression of herpes simplex virus type 1 thymidine kinase (HSV1-tk) reporter gene. Methods: Log P of 6-[{sup 18}F]FPCV was calculated in octanol/phosphate-buffered saline (PBS). Stability studies were performed in PBS and bovine serum albumin (BSA). Cell uptake was performed at various time points in wild-type cells and transduced cells. For in vivo studies, tumors were grown in nude mice by inoculation with C6 cells, wild type and tk positive. The radiotracer was intravenously injected to animals, and micro-PET imaging was performed. Biodistribution of 6-[{sup 18}F]FPCV was performed on another group of animals at different time points. Results: Log P of 6-[{sup 18}F]FPCV was -0.517. 6-[{sup 18}F]FPCV was fairly stable in PBS and BSA at 6 h. The tracer uptake in C6-tk cells was 5.5-18.8 times higher than that in wild-type cells. The plasma half-life of 6-[{sup 18}F]FPCV was as follows: {alpha} t{sub 1/2}=1.2 min and {beta} t{sub 1/2}=73.7 min. The average ratio of tumor uptake between the transduced tumor and the wild-type tumor was 1.69 at 15 min. Conclusion: Biological evaluation showed that 6-[{sup 18}F]FPCV is a potential probe for imaging HSV1-tk gene expression. However, its in vivo defluorination may limit its application in PET imaging of gene expression.

  6. A magnetic resonance imaging study on the articulatory and acoustic speech parameters of Malay vowels.

    Science.gov (United States)

    Zourmand, Alireza; Mirhassani, Seyed Mostafa; Ting, Hua-Nong; Bux, Shaik Ismail; Ng, Kwan Hoong; Bilgen, Mehmet; Jalaludin, Mohd Amin

    2014-07-25

    The phonetic properties of six Malay vowels are investigated using magnetic resonance imaging (MRI) to visualize the vocal tract in order to obtain dynamic articulatory parameters during speech production. To resolve image blurring due to the tongue movement during the scanning process, a method based on active contour extraction is used to track tongue contours. The proposed method efficiently tracks tongue contours despite the partial blurring of MRI images. Consequently, the articulatory parameters that are effectively measured as tongue movement is observed, and the specific shape of the tongue and its position for all six uttered Malay vowels are determined.Speech rehabilitation procedure demands some kind of visual perceivable prototype of speech articulation. To investigate the validity of the measured articulatory parameters based on acoustic theory of speech production, an acoustic analysis based on the uttered vowels by subjects has been performed. As the acoustic speech and articulatory parameters of uttered speech were examined, a correlation between formant frequencies and articulatory parameters was observed. The experiments reported a positive correlation between the constriction location of the tongue body and the first formant frequency, as well as a negative correlation between the constriction location of the tongue tip and the second formant frequency. The results demonstrate that the proposed method is an effective tool for the dynamic study of speech production.

  7. High susceptibility prevalence for F4+ and F18+Escherichia coli in Flemish pigs.

    Science.gov (United States)

    Nguyen, Ut V; Coddens, Annelies; Melkebeek, Vesna; Devriendt, Bert; Goetstouwers, Tiphanie; Poucke, Mario Van; Peelman, Luc; Cox, Eric

    2017-04-01

    F4 and/or F18 enterotoxigenic Escherichia coli (F4 + /F18 + ETEC) are responsible for diarrhea while F18 + verotoxigenic E. coli (F18 + VTEC) cause edema disease in pigs. Both infections can result in severe economic losses, which are mainly the result of the medication, growth retardation and mortality. The susceptibility of piglets to these pathogens is determined by the presence of F4 and F18 receptors (F4R and F18R). Understanding the composition of the susceptibility phenotypes of pigs is useful for animal health and breeding management. This study aimed to determine the prevalence of the F4 ETEC susceptibility phenotypes and F18 + E. coli susceptibility among Flemish pig breeds by using the in vitro villous adhesion assay. In this study, seven F4 ETEC susceptibility phenotypes were found, namely A (F4 ab R + , ac R + , ad R + ; 59.16%), B (F4 ab R + , ac R + , ad R - ; 6.28%), C (F4 ab R + , ac R - , ad R + ; 2.62%), D (F4 ab R - , ac R - , ad R + ; 6.28%), E (F4 ab R - , ac R - , ad R - ; 24.08%), F (F4 ab R + , ac R - , ad R - ; 1.05%) and G (F4 ab R - , ac R + , ad R - ; 0.52%). F4ab and F4ac E. coli showed a stronger degree of adhesion to the intestinal villi (53.40% and 52.88% strong adhesion, respectively), compared to F4ad E. coli (43.46% strong adhesion). Furthermore, the correlation between F4ac and F4ab adhesion was higher (r=0.78) than between F4ac and F4ad adhesion (r=0.41) and between F4ab and F4ad adhesion (r=0.57). For F18 + E. coli susceptibility, seven out of 82 pigs were F18R negative (8.54%), but only two of these seven pigs (2.44%) were also negative for F4R. As such, the chance to identify a pig that is positive for a F4 ETEC variant or F18 + E. coli is 97.56%. Therefore, significant economic losses will arise due to F4 + and/or F18 + E. coli infections in the Flemish pig population due to the high susceptibility prevalence. Copyright © 2016 Elsevier B.V. All rights reserved.

  8. Characterizing IgG4-related disease with 18F-FDG PET/CT: a prospective cohort study

    International Nuclear Information System (INIS)

    Zhang, Jingjing; Ma, Yanru; Niu, Na; Wang, Xinwei; Li, Fang; Zhu, Zhaohui; Chen, Hua; Lin, Wei; Zhang, Fengchun; Zhang, Wen; Xiao, Yu; Liang, Zhiyong

    2014-01-01

    IgG4-related disease (IgG4-RD) is an increasingly recognized clinicopathological disorder with immune-mediated inflammatory lesions mimicking malignancies. A cohort study was prospectively designed to investigate the value of 18 F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) in characterizing IgG4-RD. Thirty-five patients diagnosed with IgG4-RD according to the consensus criteria were enrolled with informed consent. All patients underwent baseline 18 F-FDG PET/CT evaluation. Among them, 29 patients underwent a second 18 F-FDG PET/CT scan after 2 to 4 weeks of steroid-based therapy. All 35 patients were found with 18 F-FDG-avid hypermetabolic lesion(s); 97.1 % (34/35) of these patients showed multi-organ involvement. Among the 35 patients, 71.4 % (25/35) patients were found with more organ involvement on 18 F-FDG PET/CT than conventional evaluations including physical examination, ultrasonography, and computed tomography (CT). 18 F-FDG PET/CT demonstrated specific image characteristics and pattern of IgG4-RD, including diffusely elevated 18 F-FDG uptake in the pancreas and salivary glands, patchy lesions in the retroperitoneal region and vascular wall, and multi-organ involvement that cannot be interpreted as metastasis. Comprehensive understanding of all involvement aided the biopsy-site selection in seven patients and the recanalization of ureteral obstruction in five patients. After 2 to 4 weeks of steroid-based therapy at 40 mg to 50 mg prednisone per day, 72.4 % (21/29) of the patients showed complete remission, whereas the others exhibited > 81.8 % decrease in 18 F-FDG uptake. F-FDG PET/CT is a useful tool for assessing organ involvement, monitoring therapeutic response, and guiding interventional treatment of IgG4-RD. The image pattern is suggested to be updated into the consensus diagnostic criteria for IgG4-RD. (orig.)

  9. 28 CFR 55.5 - Coverage under section 4(f)(4).

    Science.gov (United States)

    2010-07-01

    ... THE VOTING RIGHTS ACT REGARDING LANGUAGE MINORITY GROUPS Nature of Coverage § 55.5 Coverage under section 4(f)(4). (a) Coverage formula. Section 4(f)(4) applies to any State or political subdivision in...) Coverage may be determined with regard to section 4(f)(4) on a statewide or political subdivision basis. (1...

  10. N-(n-benzylpiperidin-4-yl)-2-[18f]fluorobenzamide: a potential ligand for PET imaging of breast cancer

    International Nuclear Information System (INIS)

    Shiue, Chyng-Yann; Shiue, Grace G.; Benard, Francois; Visonneau, Sophie; Santoli, Daniela; Alavi, Abass A.

    2000-01-01

    N-(N-Benzylpiperidin-4-yl)-2-[ 18 F]fluorobenzamide (2), a potential ligand for PET imaging of sigma receptor, has been found to be a potential agent for detection of breast cancer. In vivo studies in severe combined immunodeficient (SCID) mice bearing MDA-MB231 tumors showed that the uptake of compound 2 in these tumors was high (3.8%/g); the ratios of tumor/muscle and tumor/blood were 6.2 and 7.0, respectively, at 1 h postinjection. Pretreatment of SCID mice with haldol increased the uptake of compound 2 in blood, muscle, and other well-perfused organs while decreasing its uptake in tumors. The ratios of tumor/muscle and tumor/blood decreased from 6.2 and 7.0 to 1.3 and 1.1, respectively, at 1 h postinjection. At 2 h postinjection, the ratios of tumor/muscle and tumor/blood decreased from 4.9 and 7.8 to 1.4 and 1.4, respectively. The tumor uptake of compound 2 in SCID mice bearing primary tumor explants from a human breast cancer patient was lower than that in MDA-MB231 tumors (1.66%/g versus 3.78%/g), and the ratios of tumor/muscle and tumor/blood were 3.5 and 3.7, respectively, at 1 h postinjection. These results suggest that compound 2 may be a potential ligand for PET imaging of breast cancer

  11. Complexation and extraction of series 4f, 5f and 4d ions by dialkyldithiophosphoric acids

    International Nuclear Information System (INIS)

    Fitoussi, Richard.

    1982-04-01

    A study was carried out on the complexing and extracting properties of various dialkyldithiophosphoric acids towards ions of the 4f, 5f and 4d series. Sulphurated donors complex and extract ions of the 4f and 5f series less strongly than their oxygenated homologues. However the affinity of trivalent actinide ions for dialkythiophosphate ions is shown to be greater than that of lanthanides. The conditions of ruthenium extraction from nitric acid are defined [fr

  12. Isometries and binary images of linear block codes over ℤ4 + uℤ4 and ℤ8 + uℤ8

    Science.gov (United States)

    Sison, Virgilio; Remillion, Monica

    2017-10-01

    Let {{{F}}}2 be the binary field and ℤ2 r the residue class ring of integers modulo 2 r , where r is a positive integer. For the finite 16-element commutative local Frobenius non-chain ring ℤ4 + uℤ4, where u is nilpotent of index 2, two weight functions are considered, namely the Lee weight and the homogeneous weight. With the appropriate application of these weights, isometric maps from ℤ4 + uℤ4 to the binary spaces {{{F}}}24 and {{{F}}}28, respectively, are established via the composition of other weight-based isometries. The classical Hamming weight is used on the binary space. The resulting isometries are then applied to linear block codes over ℤ4+ uℤ4 whose images are binary codes of predicted length, which may or may not be linear. Certain lower and upper bounds on the minimum distances of the binary images are also derived in terms of the parameters of the ℤ4 + uℤ4 codes. Several new codes and their images are constructed as illustrative examples. An analogous procedure is performed successfully on the ring ℤ8 + uℤ8, where u 2 = 0, which is a commutative local Frobenius non-chain ring of order 64. It turns out that the method is possible in general for the class of rings ℤ2 r + uℤ2 r , where u 2 = 0, for any positive integer r, using the generalized Gray map from ℤ2 r to {{{F}}}2{2r-1}.

  13. Canine study on myocardial ischemic memory with 18F-FDG PET/CT imaging

    International Nuclear Information System (INIS)

    Xie Boqia; Yang Minfu; Dou Kefei; Han Chunlei; Tian Yi; Zhang Ping; Yang Zihe; Yin Jiye; Wang Hao

    2012-01-01

    Objective: To explore whether the existence and duration of ischemia measured by dynamic 18 F-FDG PET/CT imaging correlated with the extent of myocardial ischemia in a canine model of myocardial ischemia-reperfusion. Methods: Canine coronary artery occlusion was carried out for 20 min (n=4) and for 40 min (n=4) followed by 24 h of open-artery reperfusion. All dogs underwent dynamic 18 F-FDG PET/CT and 99 Tc m -MIBI SPECT imaging at baseline and 1 h and 24 h after reperfusion.Quantitative analysis of myocardial 18 F-FDG uptake was performed using Carimas Core software,and the extraction ratio of 18 F-FDG (K) was calculated by the ratio of 18 F-FDG uptake rate in the ischemic area (k ischemia ) and normoperfused region (k normoperfused ). Echocardiographic data were also acquired between each PET/CT imaging study to detect the wall motion in the ischemic and normoperfused myocardium. Paired t test and non-parametric statistical tests, measured by SPSS 19.0, were used to analyze the data. Results: Coronary occlusion produced sustained, abnormal wall motion in the ischemic region for more than 1 h. Similar K values were demonstrated between the 20 min and 40 min groups at baseline (1.02 ±0.06 and 1.03 ±0.05, Z=-0.29, P>0.05). At 1 h after reperfusion, the reperfusion regions showed normal perfusion but with increased 18 F-FDG uptake, which was higher in the 40 min ischemic group than in the 20 min ischemic group (2.31 ±0.13 and 1.87 ±0.09, Z=-2.31, P<0.05). At 24 h after reperfusion, however, only the 40 min ischemic group showed slightly higher 18 F-FDG uptake than baseline (1.15 ± 0.02 and 1.03 ±0.05, t=4.32, P<0.05), whereas no significant difference was found in the 20 min ischemic group (1.05 ± 0.04 and 1.02 ± 0.06, t=0.87, P>0.05). Histological examination of the ischemic myocardium from both groups revealed neatly arranged cells without interstitial edema, hemorrhage nor inflammatory response. Conclusions: Myocardial 'ischemic memory' was

  14. Automated Synthesis of 18F-Fluoropropoxytryptophan for Amino Acid Transporter System Imaging

    Directory of Open Access Journals (Sweden)

    I-Hong Shih

    2014-01-01

    Full Text Available Objective. This study was to develop a cGMP grade of [18F]fluoropropoxytryptophan (18F-FTP to assess tryptophan transporters using an automated synthesizer. Methods. Tosylpropoxytryptophan (Ts-TP was reacted with K18F/kryptofix complex. After column purification, solvent evaporation, and hydrolysis, the identity and purity of the product were validated by radio-TLC (1M-ammonium acetate : methanol = 4 : 1 and HPLC (C-18 column, methanol : water = 7 : 3 analyses. In vitro cellular uptake of 18F-FTP and 18F-FDG was performed in human prostate cancer cells. PET imaging studies were performed with 18F-FTP and 18F-FDG in prostate and small cell lung tumor-bearing mice (3.7 MBq/mouse, iv. Results. Radio-TLC and HPLC analyses of 18F-FTP showed that the Rf and Rt values were 0.9 and 9 min, respectively. Radiochemical purity was >99%. The radiochemical yield was 37.7% (EOS 90 min, decay corrected. Cellular uptake of 18F-FTP and 18F-FDG showed enhanced uptake as a function of incubation time. PET imaging studies showed that 18F-FTP had less tumor uptake than 18F-FDG in prostate cancer model. However, 18F-FTP had more uptake than 18F-FDG in small cell lung cancer model. Conclusion. 18F-FTP could be synthesized with high radiochemical yield. Assessment of upregulated transporters activity by 18F-FTP may provide potential applications in differential diagnosis and prediction of early treatment response.

  15. Imaging of human tooth using ultrasound based chirp-coded nonlinear time reversal acoustics

    Czech Academy of Sciences Publication Activity Database

    Dos Santos, S.; Převorovský, Zdeněk

    2011-01-01

    Roč. 51, č. 6 (2011), s. 667-674 ISSN 0041-624X Institutional research plan: CEZ:AV0Z20760514 Keywords : TR-NEWS * chirp-coded excitation * echodentography * ultrasonic imaging Subject RIV: BI - Acoustics Impact factor: 1.838, year: 2011 http://www.sciencedirect.com/science/article/pii/S0041624X11000229

  16. 4- 18F]fluoroarylalkylethers via an improved synthesis of n.c.a. 4- 18F]fluorophenol

    International Nuclear Information System (INIS)

    Ludwig, Thomas; Ermert, Johannes; Coenen, Heinz H.

    2002-01-01

    This paper describes the improved synthesis of n.c.a. 4- 18 F]fluorophenol for the preparation of 18 F-labeled alkylarylethers. Nucleophilic fluorination of substituted benzophenone derivatives yielded n.c.a. 4- 18 F]fluoro-4'-substituted benzophenones with 80- 90 % RCY, which were converted to benzoic acid phenylesters by treatment with peracetic acid. Strong electron-withdrawing substituents like nitro, cyano and trifluoromethyl favor a fluorophenyl-to-oxygen migration resulting in the formation of corresponding benzoic acid fluorophenylesters. N.c.a. 18 F]fluorophenol is almost quantitatively formed after hydrolysis and can easily be converted with alkylhalides into n.c.a. 18 F]fluoroarylalkylethers

  17. Using acoustic analysis to presort warp-prone ponderosa pine 2 by 4s before kiln-drying

    Science.gov (United States)

    Xiping Wang; William T. Simpson

    2006-01-01

    This study evaluated the potential of acoustic analysis as presorting criteria to identify warp-prone boards before kiln-drying. Dimension lumber, 38 by 89 mm (nominal 2 by 4 in.) and 2.44 m (8 it) long, sawn from open-grown small-diameter ponderosa pine trees, was acoustically tested lengthwise at green condition. Three acoustic properties (acoustic speed, rate of...

  18. Radiosynthesis and biological evaluation of 5-(3-[18F]Fluoropropyloxy)-L-tryptophan for tumor PET imaging

    International Nuclear Information System (INIS)

    He, Shanzhen; Tang, Ganghua; Hu, Kongzhen; Wang, Hongliang; Wang, Shuxia; Huang, Tingting; Liang, Xiang; Tang, Xiaolan

    2013-01-01

    Introduction: [ 18 F]FDG PET has difficulty distinguishing tumor from inflammation in the clinic because of the same high uptake in nonmalignant and inflammatory tissue. In contrast, amino acid tracers do not accumulate in inflamed tissues and thus provide an excellent opportunity for their use in clinical cancer imaging. In this study, we developed a new amino acid tracer 5-(3-[ 18 F]Fluoropropyloxy)-L-tryptophan ([ 18 F]-L-FPTP) by two-step reactions and performed its biologic evaluation. Methods: [ 18 F]-L-FPTP was prepared by [ 18 F]fluoropropylation of 5-hydroxy-L-tryptophan disodium salt and purification on C18 cartridges. The biodistribution of [ 18 F]-L-FPTP was determined in normal mice and the incorporation of [ 18 F]-L-FPTP into tissue proteins was investigated. In vitro competitive inhibition experiments were performed with Hepa1-6 hepatoma cell lines. [ 18 F]-L-FPTP PET imaging was performed on tumor-bearing and inflammation mice and compared with [ 18 F]-L-FEHTP PET. Results: The overall uncorrected radiochemical yield of [ 18 F]-L-FPTP was 21.1 ± 4.4% with a synthesis time of 60 min, the radiochemical purity was more than 99%. Biodistribution studies demonstrate high uptake of [ 18 F]-L-FPTP in liver, kidney, pancreas, and blood at the early phase, and fast clearance in most tissues over the whole observed time. The uptake studies in Hepa1-6 cells suggest that [ 18 F]-L-FPTP is transported by the amino acid transport system B 0,+ , LAT2 and ASC. [ 18 F]-L-FPTP displays good stability and is not incorporated into proteins in vitro. PET imaging shows that [ 18 F]-L-FPTP can be a better potential PET tracer for differentiating tumor from inflammation than [ 18 F]FDG and 5-(3-[ 18 F]fluoroethyloxy)-L-tryptophan ([ 18 F]-L-FEHTP), with high [ 18 F]-L-FPTP uptake ratio (2.53) of tumor to inflammation at 60 min postinjection. Conclusions: Using [ 18 F]fluoropropyl derivatives as intermediates, the new tracer [ 18 F]-L-FPTP was achieved with good yield and

  19. Spectral estimation for characterization of acoustic aberration.

    Science.gov (United States)

    Varslot, Trond; Angelsen, Bjørn; Waag, Robert C

    2004-07-01

    Spectral estimation based on acoustic backscatter from a motionless stochastic medium is described for characterization of aberration in ultrasonic imaging. The underlying assumptions for the estimation are: The correlation length of the medium is short compared to the length of the transmitted acoustic pulse, an isoplanatic region of sufficient size exists around the focal point, and the backscatter can be modeled as an ergodic stochastic process. The motivation for this work is ultrasonic imaging with aberration correction. Measurements were performed using a two-dimensional array system with 80 x 80 transducer elements and an element pitch of 0.6 mm. The f number for the measurements was 1.2 and the center frequency was 3.0 MHz with a 53% bandwidth. Relative phase of aberration was extracted from estimated cross spectra using a robust least-mean-square-error method based on an orthogonal expansion of the phase differences of neighboring wave forms as a function of frequency. Estimates of cross-spectrum phase from measurements of random scattering through a tissue-mimicking aberrator have confidence bands approximately +/- 5 degrees wide. Both phase and magnitude are in good agreement with a reference characterization obtained from a point scatterer.

  20. In vivo imaging of vesicular monoamine transporter 2 in pancreas using an {sup 18}F epoxide derivative of tetrabenazine

    Energy Technology Data Exchange (ETDEWEB)

    Kung, Hank F. [Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104 (United States); Department of Pharmacology, University of Pennsylvania, Philadelphia, PA 19104 (United States)], E-mail: kunghf@sunmac.spect.upenn.edu; Lieberman, Brian P. [Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104 (United States); Zhuang Zhiping [Avid Radiopharmaceuticals, Inc., Philadelphia, PA 19104 (United States); Oya, Shunichi; Kung Meiping [Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104 (United States); Choi, Seok Rye [Avid Radiopharmaceuticals, Inc., Philadelphia, PA 19104 (United States); Poessl, Karl; Blankemeyer, Eric; Hou, Catherine [Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104 (United States); Skovronsky, Daniel [Avid Radiopharmaceuticals, Inc., Philadelphia, PA 19104 (United States); Kilbourn, Michael [Department of Radiology, University of Michigan, Ann Arbor, MI 48109 (United States)

    2008-11-15

    Objectives: Development of imaging agents for pancreatic beta cell mass may provide tools for studying insulin-secreting beta cells and their relationship with diabetes mellitus. In this paper, a new imaging agent, [{sup 18}F](+)-2-oxiranyl-3-isobutyl-9-(3-fluoropropoxy)-10-methoxy-2,3,4,6,7, 11b-hexahydro-1H-pyrido[2,1-a]isoquinoline [{sup 18}F](+)4, which displays properties targeting vesicular monoamine transporter 2 (VMAT2) binding sites of beta cells in the pancreas, was evaluated as a positron emission tomography (PET) agent for estimating beta cell mass in vivo. The hydrolyzable epoxide group of (+)4 may provide a mechanism for shifting biodistribution from liver to kidney, thus reducing the background signal. Methods: Both {sup 18}F- and {sup 19}F-labeled (+) and (-) isomers of 4 were synthesized and evaluated. Organ distribution was carried out in normal rats. Uptake of [{sup 18}F](+)4 in pancreas of normal rats was measured and correlated with blocking studies using competing drugs, (+)dihydrotetrabenazine [(+)-DTBZ] or 9-fluoropropyl-(+)dihydro tetrabenazine [FP-(+)-DTBZ, (+)2]. Results: In vitro binding study of VMAT2 using rat brain striatum showed a K{sub i} value of 0.08 and 0.15 nM for the (+)4 and ({+-})4, respectively. The in vivo biodistribution of [{sup 18}F](+)4 in rats showed the highest uptake in the pancreas (2.68 %ID/g at 60 min postinjection). In vivo competition experiments with cold FP-(+)-DTBZ, (+)2, (3.5 mg/kg, 5 min iv pretreatment) led to a significant reduction of pancreas uptake (85% blockade at 60 min). The inactive isomer [{sup 18}F](-)4 showed significantly lower pancreas uptake (0.22 %ID/g at 30 min postinjection). Animal PET imaging studies of [{sup 18}F](+)4 in normal rats demonstrated an avid pancreatic uptake in rats. Conclusion: The preliminary results suggest that the epoxide, [{sup 18}F](+)4, is highly selective in binding to VMAT2 and it has an excellent uptake in the pancreas of rats. The liver uptake was significantly

  1. On the use of [18F]DOPA as an imaging biomarker for transplanted islet mass

    International Nuclear Information System (INIS)

    Eriksson, Olof; Mintz, Akiva; Liu, Chengyang; Yu, Ming; Naji, Ali; Alavi, Abass

    2014-01-01

    Islet transplantation is being developed as a potential cure for patients with type 1 diabetes. There is a need for non-invasive imaging techniques for the quantification of transplanted islets, as current transplantation sites are associated with a substantial loss of islet viability. The dopaminergic metabolic pathway is present in the islets; therefore, we propose Fluorine-18 labeled L-3,4-dihydroxyphenylalanine ([ 18 F]DOPA) as a biomarker for transplanted islet mass. The expression of enzymes involved in the dopaminergic metabolic pathway was investigated in both native and transplanted human islets. The specific uptake of [ 18 F]DOPA in islets and immortalized beta cells was studied in vitro by selective blocking of dopa decarboxylase (DDC). Initial in vivo positron emission tomography (PET) imaging of viable subcutaneous human islets was performed using [ 18 F]DOPA. DDC and vesicular monoamine transporter 2 are co-localized with insulin in the native human pancreas, and the expression is retained after transplantation. Islet uptake of the [ 18 F]DOPA could be modulated by inhibiting DDC, indicating that the uptake followed the normal dopaminergic metabolic pathway. In vivo imaging revealed [ 18 F]DOPA uptake at the site of the functional islet graft. Based on the in vitro and in vivo results presented in this study, we propose to further validate [ 18 F]DOPA-PET as a sensitive imaging modality for imaging extrahepatically transplanted islets. (author)

  2. Thermodynamic assessment of the LiF–ThF{sub 4}–PuF{sub 3}–UF{sub 4} system

    Energy Technology Data Exchange (ETDEWEB)

    Capelli, E. [European Commission, Joint Research Centre, Institute for Transuranium Elements, P.O. Box 2340, 76125 Karlsruhe (Germany); Department of Radiation Science and Technology, Faculty of Applied Physics, Delft University of Technology, Delft 2629JB (Netherlands); Beneš, O., E-mail: ondrej.benes@ec.europa.eu [European Commission, Joint Research Centre, Institute for Transuranium Elements, P.O. Box 2340, 76125 Karlsruhe (Germany); Konings, R.J.M. [European Commission, Joint Research Centre, Institute for Transuranium Elements, P.O. Box 2340, 76125 Karlsruhe (Germany); Department of Radiation Science and Technology, Faculty of Applied Physics, Delft University of Technology, Delft 2629JB (Netherlands)

    2015-07-15

    The LiF–ThF{sub 4}–PuF{sub 3}–UF{sub 4} system is the reference salt mixture considered for the Molten Salt Fast Reactor (MSFR) concept started with PuF{sub 3}. In order to obtain the complete thermodynamic description of this quaternary system, two binary systems (ThF{sub 4}–PuF{sub 3} and UF{sub 4}–PuF{sub 3}) and two ternary systems (LiF–ThF{sub 4}–PuF{sub 3} and LiF–UF{sub 4}–PuF{sub 3}) have been assessed for the first time. The similarities between CeF{sub 3}/PuF{sub 3} and ThF{sub 4}/UF{sub 4} compounds have been taken into account for the presented optimization as well as in the experimental measurements performed, which have confirmed the temperatures predicted by the model. Moreover, the experimental results and the thermodynamic database developed have been used to identify potential compositions for the MSFR fuel and to evaluate the influence of partial substitution of ThF{sub 4} by UF{sub 4} in the salt.

  3. Radiosynthesis and biological evaluation of 18F-labeled 4-anilinoquinazoline derivative (18F-FEA-Erlotinib) as a potential EGFR PET agent.

    Science.gov (United States)

    Huang, Shun; Han, Yanjiang; Chen, Min; Hu, Kongzhen; Qi, Yongshuai; Sun, Penghui; Wang, Men; Wu, Hubing; Li, Guiping; Wang, Quanshi; Du, Zhiyun; Zhang, Kun; Zhao, Suqing; Zheng, Xi

    2018-04-01

    Epidermal growth factor receptor (EGFR) has gained significant attention as a therapeutic target. Several EGFR targeting drugs (Gefitinib and Erlotinib) have been approved by US Food and Drug Administration (FDA) and have received high approval in clinical treatment. Nevertheless, the curative effect of these medicines varied in many solid tumors because of the different levels of expression and mutations of EGFR. Therefore, several PET radiotracers have been developed for the selective treatment of responsive patients who undergo PET/CT imaging for tyrosine kinase inhibitor (TKI) therapy. In this study, a novel fluorine-18 labeled 4-anilinoquinazoline based PET tracer, 1N-(3-(1-(2- 18 F-fluoroethyl)-1H-1,2,3-triazol-4-yl)phenyl)-6,7-bis(2-methoxyethoxy)quinazolin-4-amine ( 18 F-FEA-Erlotinib), was synthesized and biological evaluation was performed in vitro and in vivo. 18 F-FEA-Erlotinib was achieved within 50min with over 88% radiochemical yield (decay corrected RCY), an average specific activity over 50GBq/μmol, and over 99% radiochemical purity. In vitro stability study showed no decomposition of 18 F-FEA-Erlotinib after incubated in PBS and FBS for 2h. Cellular uptake and efflux experiment results indicated the specific binding of 18 F-FEA-Erlotinib to HCC827 cell line with EGFR exon 19 deletions. In vivo, Biodistribution studies revealed that 18 F-FEA-Erlotinib exhibited rapid blood clearance both through hepatobiliary and renal excretion. The tumor uptake of 18 F-FEA-Erlotinib in HepG2, HCC827, and A431 tumor xenografts, with different EGFR expression and mutations, was visualized in PET images. Our results demonstrate the feasibility of using 18 F-FEA-Erlotinib as a PET tracer for screening EGFR TKIs sensitive patients. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. One-step radiosynthesis of {sup 18}F-AlF-NOTA-RGD{sub 2} for tumor angiogenesis PET imaging

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Shuanglong; Liu, Hongguang; Xu, Yingding; Cheng, Zhen [Stanford University, Molecular Imaging Program at Stanford (MIPS), Canary Center at Stanford for Cancer Early Detection, Bio-X Program, Department of Radiology, Stanford, CA (United States); Jiang, Han [Stanford University, Molecular Imaging Program at Stanford (MIPS), Canary Center at Stanford for Cancer Early Detection, Bio-X Program, Department of Radiology, Stanford, CA (United States); Institute of Nuclear Medicine and Molecular Imaging, and the Second Affiliated Hospital of Zhejiang University School of Medicine, Key Laboratory of Medical Molecular Imaging of Zhejiang Province, Department of Nuclear Medicine, Medical PET Center, Hangzhou, Zhejiang (China); Zhang, Hong [Institute of Nuclear Medicine and Molecular Imaging, and the Second Affiliated Hospital of Zhejiang University School of Medicine, Key Laboratory of Medical Molecular Imaging of Zhejiang Province, Department of Nuclear Medicine, Medical PET Center, Hangzhou, Zhejiang (China)

    2011-09-15

    One of the major obstacles of the clinical translation of {sup 18}F-labeled arginine-glycine-aspartic acid (RGD) peptides has been the laborious multistep radiosynthesis. In order to facilitate the application of RGD-based positron emission tomography (PET) probes in the clinical setting we investigated in this study the feasibility of using the chelation reaction between Al{sup 18}F and a macrocyclic chelator-conjugated dimeric RGD peptide as a simple one-step {sup 18}F labeling strategy for development of a PET probe for tumor angiogenesis imaging. Dimeric cyclic peptide E[c(RGDyK)]{sub 2} (RGD{sub 2}) was first conjugated with a macrocyclic chelator, 1,4,7-triazacyclononane-1,4,7-triacetic acid (NOTA), and the resulting bioconjugate NOTA-RGD{sub 2} was then radiofluorinated via Al{sup 18}F intermediate to synthesize {sup 18}F-AlF-NOTA-RGD{sub 2}. Integrin binding affinities of the peptides were assessed by a U87MG cell-based receptor binding assay using {sup 125}I-echistatin as the radioligand. The tumor targeting efficacy and in vivo profile of {sup 18}F-AlF-NOTA-RGD{sub 2} were further evaluated in a subcutaneous U87MG glioblastoma xenograft model by microPET and biodistribution. NOTA-RGD{sub 2} was successfully {sup 18}F-fluorinated with good yield within 40 min using the Al{sup 18}F intermediate. The IC{sub 50} of {sup 19}F-AlF-NOTA-RGD{sub 2} was determined to be 46 {+-} 4.4 nM. Quantitative microPET studies demonstrated that {sup 18}F-AlF-NOTA-RGD{sub 2} showed high tumor uptake, fast clearance from the body, and good tumor to normal organ ratios. NOTA-RGD{sub 2} bioconjugate has been successfully prepared and labeled with Al{sup 18}F in one single step of radiosynthesis. The favorable in vivo performance and the short radiosynthetic route of {sup 18}F-AlF-NOTA-RGD{sub 2} warrant further optimization of the probe and the radiofluorination strategy to accelerate the clinical translation of {sup 18}F-labeled RGD peptides. (orig.)

  5. Contrast-enhanced 18F-fluorodeoxyglucose positron emission tomography/computed tomography in immunoglobulin G4-related retroperitoneal fibrosis

    International Nuclear Information System (INIS)

    Sharma, Punit; Chatterjee, Piyali

    2015-01-01

    Immunoglobulin G4 (IgG4)-related disease encompasses a wide variety of immune disorders previously thought be distinct. IgG4-related retroperitoneal fibrosis is one such entity. Metabolic imaging with 18 F-fluorodeoxyglucose ( 18 F-FDG) positron emission tomography/computed tomography (PET/CT) can be useful in the management of IgG4-related retroperitoneal fibrosis. We here discuss the case of 63-year-old male with IgG4-related retroperitoneal fibrosis and the role, 18 F-FDG PET/CT played in his management

  6. Imaging Radiation-Induced Gastrointestinal, Bone Marrow Injury and Recovery Kinetics Using 18F-FDG PET.

    Science.gov (United States)

    Tang, Tien T; Rendon, David A; Zawaski, Janice A; Afshar, Solmaz F; Kaffes, Caterina K; Sabek, Omaima M; Gaber, M Waleed

    2017-01-01

    Positron emission tomography using 18F-Fluro-deoxy-glucose (18F-FDG) is a useful tool to detect regions of inflammation in patients. We utilized this imaging technique to investigate the kinetics of gastrointestinal recovery after radiation exposure and the role of bone marrow in the recovery process. Male Sprague-Dawley rats were either sham irradiated, irradiated with their upper half body shielded (UHBS) at a dose of 7.5 Gy, or whole body irradiated (WBI) with 4 or 7.5 Gy. Animals were imaged using 18F-FDG PET/CT at 5, 10 and 35 days post-radiation exposure. The gastrointestinal tract and bone marrow were analyzed for 18F-FDG uptake. Tissue was collected at all-time points for histological analysis. Following 7.5 Gy irradiation, there was a significant increase in inflammation in the gastrointestinal tract as indicated by the significantly higher 18F-FDG uptake compared to sham. UHBS animals had a significantly higher activity compared to 7.5 Gy WBI at 5 days post-exposure. Animals that received 4 Gy WBI did not show any significant increase in uptake compared to sham. Analysis of the bone marrow showed a significant decrease of uptake in the 7.5 Gy animals 5 days post-irradiation, albeit not observed in the 4 Gy group. Interestingly, as the metabolic activity of the gastrointestinal tract returned to sham levels in UHBS animals it was accompanied by an increase in metabolic activity in the bone marrow. At 35 days post-exposure both gastrointestinal tract and bone marrow 18F-FDG uptake returned to sham levels. 18F-FDG imaging is a tool that can be used to study the inflammatory response of the gastrointestinal tract and changes in bone marrow metabolism caused by radiation exposure. The recovery of the gastrointestinal tract coincides with an increase in bone marrow metabolism in partially shielded animals. These findings further demonstrate the relationship between the gastrointestinal syndrome and bone marrow recovery, and that this interaction can be studied

  7. Imaging Radiation-Induced Gastrointestinal, Bone Marrow Injury and Recovery Kinetics Using 18F-FDG PET.

    Directory of Open Access Journals (Sweden)

    Tien T Tang

    Full Text Available Positron emission tomography using 18F-Fluro-deoxy-glucose (18F-FDG is a useful tool to detect regions of inflammation in patients. We utilized this imaging technique to investigate the kinetics of gastrointestinal recovery after radiation exposure and the role of bone marrow in the recovery process. Male Sprague-Dawley rats were either sham irradiated, irradiated with their upper half body shielded (UHBS at a dose of 7.5 Gy, or whole body irradiated (WBI with 4 or 7.5 Gy. Animals were imaged using 18F-FDG PET/CT at 5, 10 and 35 days post-radiation exposure. The gastrointestinal tract and bone marrow were analyzed for 18F-FDG uptake. Tissue was collected at all-time points for histological analysis. Following 7.5 Gy irradiation, there was a significant increase in inflammation in the gastrointestinal tract as indicated by the significantly higher 18F-FDG uptake compared to sham. UHBS animals had a significantly higher activity compared to 7.5 Gy WBI at 5 days post-exposure. Animals that received 4 Gy WBI did not show any significant increase in uptake compared to sham. Analysis of the bone marrow showed a significant decrease of uptake in the 7.5 Gy animals 5 days post-irradiation, albeit not observed in the 4 Gy group. Interestingly, as the metabolic activity of the gastrointestinal tract returned to sham levels in UHBS animals it was accompanied by an increase in metabolic activity in the bone marrow. At 35 days post-exposure both gastrointestinal tract and bone marrow 18F-FDG uptake returned to sham levels. 18F-FDG imaging is a tool that can be used to study the inflammatory response of the gastrointestinal tract and changes in bone marrow metabolism caused by radiation exposure. The recovery of the gastrointestinal tract coincides with an increase in bone marrow metabolism in partially shielded animals. These findings further demonstrate the relationship between the gastrointestinal syndrome and bone marrow recovery, and that this

  8. Quantitative PET Imaging of Tissue Factor Expression Using 18F-labled Active Site Inhibited Factor VII

    DEFF Research Database (Denmark)

    Nielsen, Carsten H; Erlandsson, Maria; Jeppesen, Troels E

    2016-01-01

    Tissue factor (TF) is up regulated in many solid tumors and its expression is linked to tumor angiogenesis, invasion, metastasis and prognosis. A non-invasive assessment of tumor TF expression status is therefore of obvious clinical relevance. Factor VII (FVII) is the natural ligand to TF. Here we...... report the development of a new PET tracer for specific imaging of TF using an (18)F-labeled derivative of FVII. METHODS: Active site inhibited factor VIIa (FVIIai) was obtained by inactivation with phenylalanine-phenylalanine-arginine-chloromethyl ketone. FVIIai was radiolabeled with N-succinimidyl 4......-[(18)F]-fluorobenzoate ([(18)F]SFB) and purified. The corresponding product, [(18)F]FVIIai, was injected into nude mice with subcutaneous human pancreatic xenograft tumors (BxPC-3) and investigated using small animal PET/CT imaging 1, 2 and 4 hours after injection. Ex vivo biodistribution was performed...

  9. Methodological development of topographic correction in 2D/3D ToF-SIMS images using AFM images

    Science.gov (United States)

    Jung, Seokwon; Lee, Nodo; Choi, Myungshin; Lee, Jungmin; Cho, Eunkyunng; Joo, Minho

    2018-02-01

    Time-of-flight secondary-ion mass spectrometry (ToF-SIMS) is an emerging technique that provides chemical information directly from the surface of electronic materials, e.g. OLED and solar cell. It is very versatile and highly sensitive mass spectrometric technique that provides surface molecular information with their lateral distribution as a two-dimensional (2D) molecular image. Extending the usefulness of ToF-SIMS, a 3D molecular image can be generated by acquiring multiple 2D images in a stack. These imaging techniques by ToF-SIMS provide an insight into understanding the complex structures of unknown composition in electronic material. However, one drawback in ToF-SIMS is not able to represent topographical information in 2D and 3D mapping images. To overcome this technical limitation, topographic information by ex-situ technique such as atomic force microscopy (AFM) has been combined with chemical information from SIMS that provides both chemical and physical information in one image. The key to combine two different images obtained from ToF-SIMS and AFM techniques is to develop the image processing algorithm, which performs resize and alignment by comparing the specific pixel information of each image. In this work, we present methodological development of the semiautomatic alignment and the 3D structure interpolation system for the combination of 2D/3D images obtained by ToF-SIMS and AFM measurements, which allows providing useful analytical information in a single representation.

  10. Use of Molecular Imaging Markers of Glycolysis, Hypoxia and Proliferation (18F-FDG, 64Cu-ATSM and 18F-FLT) in a Dog with Fibrosarcoma

    DEFF Research Database (Denmark)

    Zornhagen, Kamilla; Clausen, Malene; Hansen, Anders Elias

    2015-01-01

    of cancer patients. A dog with fibrosarcoma was imaged using 18F-FDG, 64Cu-ATSM, and 18F-FLT before, during, and after 10 fractions of 4.5 Gy radiotherapy. Uptake of all tracers decreased during treatment. Fluctuations in 18F-FDG and 18F-FLT PET uptakes and a heterogeneous spatial distribution of the three......Glycolysis, hypoxia, and proliferation are important factors in the tumor microenvironment contributing to treatment-resistant aggressiveness. Imaging these factors using combined functional positron emission tomography and computed tomography can potentially guide diagnosis and management...... tracers were seen. Tracer distributions partially overlapped. It appears that each tracer provides distinct information about tumor heterogeneity and treatment response....

  11. Localized Acoustic Surface Modes

    KAUST Repository

    Farhat, Mohamed

    2015-08-04

    We introduce the concept of localized acoustic surface modes (ASMs). We demonstrate that they are induced on a two-dimensional cylindrical rigid surface with subwavelength corrugations under excitation by an incident acoustic plane wave. Our results show that the corrugated rigid surface is acoustically equivalent to a cylindrical scatterer with uniform mass density that can be represented using a Drude-like model. This, indeed, suggests that plasmonic-like acoustic materials can be engineered with potential applications in various areas including sensing, imaging, and cloaking.

  12. Synthesis and biological evaluation of [18F]tetrafluoroborate: a PET imaging agent for thyroid disease and reporter gene imaging of the sodium/iodide symporter

    International Nuclear Information System (INIS)

    Jauregui-Osoro, Maite; Sunassee, Kavitha; Weeks, Amanda J.; Berry, David J.; Paul, Rowena L.; Cleij, Marcel; O'Doherty, Michael J.; Marsden, Paul K.; Szanda, Istvan; Blower, Philip J.; Banga, Jasvinder Paul; Clarke, Susan E.M.; Ballinger, James R.; Cheng, Sheue-Yann

    2010-01-01

    The human sodium/iodide symporter (hNIS) is a well-established target in thyroid disease and reporter gene imaging using gamma emitters 123 I-iodide, 131 I-iodide and 99m Tc-pertechnetate. However, no PET imaging agent is routinely available. The aim of this study was to prepare and evaluate 18 F-labelled tetrafluoroborate ([ 18 F]TFB) for PET imaging of hNIS. [ 18 F]TFB was prepared by isotopic exchange of BF 4 - with [ 18 F]fluoride in hot hydrochloric acid and purified using an alumina column. Its identity, purity and stability in serum were determined by HPLC, thin-layer chromatography (TLC) and mass spectrometry. Its interaction with NIS was assessed in vitro using FRTL-5 rat thyroid cells, with and without stimulation by thyroid-stimulating hormone (TSH), in the presence and absence of perchlorate. Biodistribution and PET imaging studies were performed using BALB/c mice, with and without perchlorate inhibition. [ 18 F]TFB was readily prepared with specific activity of 10 GBq/mg. It showed rapid accumulation in FRTL-5 cells that was stimulated by TSH and inhibited by perchlorate, and rapid specific accumulation in vivo in thyroid (SUV = 72 after 1 h) and stomach that was inhibited 95% by perchlorate. [ 18 F]TFB is an easily prepared PET imaging agent for rodent NIS and should be evaluated for hNIS PET imaging in humans. (orig.)

  13. Imaging of lung metastasis tumor mouse model using [{sup 18}F]FDG small animal PET and CT

    Energy Technology Data Exchange (ETDEWEB)

    Kim, June Youp; Woo, Sang Keun; Lee, Tae Sup [Korea Institute of Radiological and Medical Sciences (KIRAMS), Seoul (Korea, Republic of)] (and others)

    2007-02-15

    The purpose of this study is to image metastaic lung melanoma model with optimal pre-conditions for animal handling by using [{sup 18}F]FDG small animal PET and clinical CT. The pre-conditions for lung region tumor imaging were 16-22 h fasting and warming temperature at 30 .deg. C. Small animal PET image was obtained at 60 min postinjection of 7.4 MBq [{sup 18}F]FDG and compared pattern of [{sup 18}F]FDG uptake and glucose standard uptake value (SUVG) of lung region between Ketamine/Xylazine (Ke/Xy) and Isoflurane (Iso) anesthetized group in normal mice. Metastasis tumor mouse model to lung was established by intravenous injection of B16-F10 cells in C57BL/6 mice. In lung metastasis tumor model, [{sup 18}F]FDG image was obtained and fused with anatomical clinical CT image. Average blood glucose concentration in normal mice were 128.0 {+-} 22.87 and 86.0 {+-} 21.65 mg/dL in Ke/Xy group and Iso group, respectively. Ke/Xy group showed 1.5 fold higher blood glucose concentration than Iso group. Lung to Background ratio (L/B) in SUVG image was 8.6 {+-} 0.48 and 12.1 {+-}0.63 in Ke/Xy group and Iso group, respectively. In tumor detection in lung region, [{sup 18}F]FDG image of Iso group was better than that of Ke/Xy group, because of high L/B ratio. Metastatic tumor location in [{sup 18}F]FDG small animal PET image was confirmed by fusion image using clinical CT. Tumor imaging in small animal lung region with [{sup 18}F]FDG small animal PET should be considered pre-conditions which fasting, warming and an anesthesia during [{sup 18}F]FDG uptake. Fused imaging with small animal PET and CT image could be useful for the detection of metastatic tumor in lung region.

  14. Infection Imaging With 18F-FDS and First-in-Human Evaluation

    International Nuclear Information System (INIS)

    Yao, Shaobo; Xing, Haiqun; Zhu, Wenjia; Wu, Zhanhong; Zhang, Yingqiang; Ma, Yanru; Liu, Yimin; Huo, Li; Zhu, Zhaohui; Li, Zibo; Li, Fang

    2016-01-01

    Purpose: The noninvasive imaging of bacterial infections is critical in order to reduce mortality and morbidity caused by these diseases. The recently reported 18 F-FDS ( 18 F-2-fluorodeoxy sorbitol) as a PET (positron emission tomography) tracer can be used to image Enterobacteriaceae-specific infections and provides a potential alternative to this problem compared with other probes for imaging infections. In this study, automatic synthesis, validation of 18 F-FDS and a first-in-human study were performed and discussed. Methods: A multifunctional synthesis module was employed for the radiosynthesis of 18 F-FDG ( 18 F-2-fluorodeoxy glucose) and 18 F-FDS starting from 18 F ion using two-pot three-step fully automated reactions. The behavior of 18 F-FDS as an in vivo imaging probe for infections was evaluated in an Escherichia coli mouse infection model. The first detailed pharmacokinetic and biodistribution parameters were obtained from healthy human volunteers. Results: The uptake of 18 F-FDS in an E. coli mouse-myositis infection model was easily differentiated from other organs and normal muscle. Intensive lesion uptake declined after antibiotic treatment. In the pilot human study, no adverse effects due to 18 F-FDS were observed up to 24 h post-injection. The radiotracer was rapidly cleared from the circulation and excreted mainly through the urinary system. Conclusion: We conclude that 18 F-FDS PET holds great potential for appropriate and effective for the imaging of bacterial infections in vivo. These preliminary results indicate that further clinical studies are warranted.

  15. Estimating transmission parameters of F4 + E. coli for F4-receptor-positive and -negative piglets: one-to-one transmission experiment

    NARCIS (Netherlands)

    Geenen, P.L.; Meulen, van der J.; Bouma, A.; Jong, de M.C.M.

    2004-01-01

    F4+ Escherichia coli is an important agent of post-weaning diarrhoea in piglets. Piglets that express an adhesion site for F4+ E. coli in their small intestine (F4R+) shed higher numbers of F4+ E. coli than piglets lacking this site (F4R[minus sign]). We hypothesized that F4R+ piglets are more

  16. A spinal cord window chamber model for in vivo longitudinal multimodal optical and acoustic imaging in a murine model.

    Directory of Open Access Journals (Sweden)

    Sarah A Figley

    Full Text Available In vivo and direct imaging of the murine spinal cord and its vasculature using multimodal (optical and acoustic imaging techniques could significantly advance preclinical studies of the spinal cord. Such intrinsically high resolution and complementary imaging technologies could provide a powerful means of quantitatively monitoring changes in anatomy, structure, physiology and function of the living cord over time after traumatic injury, onset of disease, or therapeutic intervention. However, longitudinal in vivo imaging of the intact spinal cord in rodent models has been challenging, requiring repeated surgeries to expose the cord for imaging or sacrifice of animals at various time points for ex vivo tissue analysis. To address these limitations, we have developed an implantable spinal cord window chamber (SCWC device and procedures in mice for repeated multimodal intravital microscopic imaging of the cord and its vasculature in situ. We present methodology for using our SCWC to achieve spatially co-registered optical-acoustic imaging performed serially for up to four weeks, without damaging the cord or induction of locomotor deficits in implanted animals. To demonstrate the feasibility, we used the SCWC model to study the response of the normal spinal cord vasculature to ionizing radiation over time using white light and fluorescence microscopy combined with optical coherence tomography (OCT in vivo. In vivo power Doppler ultrasound and photoacoustics were used to directly visualize the cord and vascular structures and to measure hemoglobin oxygen saturation through the complete spinal cord, respectively. The model was also used for intravital imaging of spinal micrometastases resulting from primary brain tumor using fluorescence and bioluminescence imaging. Our SCWC model overcomes previous in vivo imaging challenges, and our data provide evidence of the broader utility of hybridized optical-acoustic imaging methods for obtaining

  17. (18)F-FDG PET imaging of murine atherosclerosis

    DEFF Research Database (Denmark)

    Hag, Anne Mette Fisker; Pedersen, Sune Folke; Christoffersen, Christina

    2012-01-01

    To study whether (18)F-FDG can be used for in vivo imaging of atherogenesis by examining the correlation between (18)F-FDG uptake and gene expression of key molecular markers of atherosclerosis in apoE(-/-) mice....

  18. Magnetic upconverting fluorescent NaGdF4:Ln3+ and iron-oxide@NaGdF4:Ln3+ nanoparticles

    Science.gov (United States)

    Shrivastava, Navadeep; Rocha, Uéslen; Muraca, Diego; Jacinto, Carlos; Moreno, Sergio; Vargas, J. M.; Sharma, S. K.

    2018-05-01

    Microwave assisted solvothermal method has been employed to synthesize multifunctional upconverting β-NaGdF4:Ln3+ and magnetic-upconverting Fe3O4/γ-Fe2O3@NaGdF4:Ln3+ (Ln = Yb and Er) nanoparticles. The powder x-ray diffraction data confirms the hexagonal structure of NaGdF4:Ln3+ and high resolution transmission electron microscopy shows the formation of rod shaped NaGdF4:Ln3+ (˜ 20 nm) and ovoid shaped Fe3O4/γ-Fe2O3@NaGdF4:Ln3+ (˜ 15 nm) nanoparticles. The magnetic hysteresis at 300 K for β-NaGdF4:Ln3+ demonstrates paramagnetic features, whereas iron-oxide@β-NaGdF4:Ln3+ exhibits superparamagnetic behavior along with a linear component at large applied field due to paramagnetic NaGdF4 matrix. Both nanoparticle samples provide an excellent green emitting [(2H11/2, 4S3/2)→4I15/2 (˜ 540 nm)] upconversion luminescence emission under excitation at 980 nm. The energy migration between Yb and Er in NaGdF4 matrix has been explored from 300-800 nm. Intensity variation of blue, green and red lines and the observed luminescence quenching due to the presence of Fe3O4/γ-Fe2O3 in the composite has been proposed. These kinds of materials contain magnetic and luminescence characteristics into single nanoparticle open new possibility for bioimaging applications.

  19. Evaluation of 4-[{sup 18}F]fluorobenzoyl-FALGEA-NH{sub 2} as a positron emission tomography tracer for epidermal growth factor receptor mutation variant III imaging in cancer

    Energy Technology Data Exchange (ETDEWEB)

    Lund Denholt, Charlotte, E-mail: charlotte.lund.denholt@rh.regionh.d [Department of Clinical Physiology, Nuclear Medicine and PET, Copenhagen University Hospital, Rigshospitalet, 2100 Copenhagen O (Denmark); Binderup, Tina [Department of Clinical Physiology, Nuclear Medicine and PET, Copenhagen University Hospital, Rigshospitalet, 2100 Copenhagen O (Denmark); Cluster for Molecular Imaging, Faculty of Health Sciences, University of Copenhagen, 2200 Copenhagen N (Denmark); Stockhausen, Marie-Therese; Skovgaard Poulsen, Hans [Department of Radiation Biology, Copenhagen University Hospital Rigshospitalet, 2100 Copenhagen O (Denmark); Spang-Thomsen, Mogens [Institute of Molecular Pathology, University of Copenhagen, 2200 Copenhagen N (Denmark); Hansen, Paul Robert [IGM-Bioorganic Chemistry, Faculty of Life Science, University of Copenhagen, 1871 Frederiksberg C (Denmark); Gillings, Nic [Department of Clinical Physiology, Nuclear Medicine and PET, Copenhagen University Hospital, Rigshospitalet, 2100 Copenhagen O (Denmark); Kjaer, Andreas [Department of Clinical Physiology, Nuclear Medicine and PET, Copenhagen University Hospital, Rigshospitalet, 2100 Copenhagen O (Denmark); Cluster for Molecular Imaging, Faculty of Health Sciences, University of Copenhagen, 2200 Copenhagen N (Denmark)

    2011-05-15

    Introduction: This study describes the radiosynthesis, in vitro and in vivo evaluation of the novel small peptide radioligand, 4-[{sup 18}F]fluorobenzoyl-Phe-Ala-Leu-Gly-Glu-Ala-NH{sub 2,} ([{sup 18}F]FBA-FALGEA-NH{sub 2}) as a positron emission tomography (PET) tracer for imaging of the cancer specific epidermal growth factor receptor (EGFR) variant III mutation, EGFRvIII. Methods: For affinity, stability and PET measurements, H-FALGEA-NH{sub 2} was radiolabelled using 4-[{sup 18}F]fluorobenzoic acid ([{sup 18}F]FBA). The binding affinity of ([{sup 18}F]FBA)-FALGEA-NH{sub 2} was measured on EGFRvIII expressing cells, NR6M. Stability studies in vitro and in vivo were carried out in blood plasma from nude mice. PET investigations of [{sup 18}F]FBA-FALGEA-NH{sub 2} were performed on a MicroPET scanner, using seven nude mice xenografted subcutaneously with human glioblastoma multiforme (GBM) tumours, expressing the EGFRvIII in its native form, and five nude mice xenografted subcutaneously with GBM tumours lacking EGFRvIII expression. Images of [{sup 18}F]FDG were also obtained for comparison. The mice were injected with 5-10 MBq of the radiolabelled peptide or [{sup 18}F]FDG. Furthermore, the gene expression of EGFRvIII in the tumours was determined using quantitative real-time PCR. Results: Radiolabelling and purification was achieved within 180 min, with overall radiochemical yields of 2.6-9.8% (decay-corrected) and an average specific radioactivity of 6.4 GBq/{mu}mol. The binding affinity (K{sub d}) of [{sup 18}F]FBA-FALGEA-NH{sub 2} to EGFRvIII expressing cells was determined to be 23 nM. The radiolabelled peptide was moderately stable in the plasma from nude mice where 53% of the peptide was intact after 60 min of incubation in plasma but rapidly degraded in vivo, where no intact peptide was observed in plasma 5 min post-injection. The PET imaging showed that [{sup 18}F]FBA-FALGEA-NH{sub 2} accumulated preferentially in the human GBM xenografts which expressed

  20. Differential diagnosis of Parkinsonism using dual phase F 18 FP CIT PET imaging

    International Nuclear Information System (INIS)

    Jin, So Young; Oh, Min Young; Ok, Seung Jun; Oh, Jung Su; Lee, Sang Ju; Chung, Sun Ju; Lee, Chong Sik; Kim, Jae Seung

    2012-01-01

    Dopamine transporter (DAT) imaging can demonstrate presynaptic dopaminergic neuronal loss in Parkinson's disease (PD). However, differentiating atypical parkinsonism (APD) from PD is often difficult. We investigated the usefulness of dual phase F 18 FP CIT positron emission tomography (PET) imaging in the differential diagnosis of parkinsonism. Ninety eight subjects [five normal, seven drug induced parkinsonism (DIP), five essential tremor (ET), 24 PD, 20 multiple system atrophy parkinson type (MSA-P), 13 multiple system atrophy cerebellar type (MSA-C), 13 progressive supranuclear palsy (PSP), and 11 dementia with Lewy bodies(DLB)] underwent F 18 FP CIT PET. PET images were acquired at 5 min (early phase) and 3 h (late phase) after F 18 FP CIT administration (185MBq). Regional uptake pattern of cerebral and cerebellar hemispheres was assessed on early phase images, using visual, quantitative, and statistical parametric mapping (SPM) analyses. Striatal DAT binding was normal in normal, ET, DIP, and MSA C groups, but abnormal in PD, MSA P PSP, and DLB groups. No difference was found in regional uptake on early phase images among normal DAT binding groups, except in the MSA C group. Abnormal DAT binding groups showed different regional uptake pattern on early phase images compared with PD in SPM analysis (FDR<0.05). When discriminating APD from PD, visual interpretation of the early phase image showed high diagnostic sensitivity and specificity (75.4% and 100%, respectively). Regarding the ability to distinguish specific APD, sensitivities were 81% for MSA P, 77% for MSA C, 23% for PSP, and 54.5% for DLB. Dual phase F 18 FP CIT PET imaging is useful in demonstrating striatal DAT loss in neurodegenerative parkinsonism, and also in differentiating APD, particularly MSA, from PD

  1. Differential diagnosis of Parkinsonism using dual phase F 18 FP CIT PET imaging

    Energy Technology Data Exchange (ETDEWEB)

    Jin, So Young; Oh, Min Young; Ok, Seung Jun; Oh, Jung Su; Lee, Sang Ju; Chung, Sun Ju; Lee, Chong Sik; Kim, Jae Seung [Univ. of Ulsan, Seoul (Korea, Republic of)

    2012-03-15

    Dopamine transporter (DAT) imaging can demonstrate presynaptic dopaminergic neuronal loss in Parkinson's disease (PD). However, differentiating atypical parkinsonism (APD) from PD is often difficult. We investigated the usefulness of dual phase F 18 FP CIT positron emission tomography (PET) imaging in the differential diagnosis of parkinsonism. Ninety eight subjects [five normal, seven drug induced parkinsonism (DIP), five essential tremor (ET), 24 PD, 20 multiple system atrophy parkinson type (MSA-P), 13 multiple system atrophy cerebellar type (MSA-C), 13 progressive supranuclear palsy (PSP), and 11 dementia with Lewy bodies(DLB)] underwent F 18 FP CIT PET. PET images were acquired at 5 min (early phase) and 3 h (late phase) after F 18 FP CIT administration (185MBq). Regional uptake pattern of cerebral and cerebellar hemispheres was assessed on early phase images, using visual, quantitative, and statistical parametric mapping (SPM) analyses. Striatal DAT binding was normal in normal, ET, DIP, and MSA C groups, but abnormal in PD, MSA P PSP, and DLB groups. No difference was found in regional uptake on early phase images among normal DAT binding groups, except in the MSA C group. Abnormal DAT binding groups showed different regional uptake pattern on early phase images compared with PD in SPM analysis (FDR<0.05). When discriminating APD from PD, visual interpretation of the early phase image showed high diagnostic sensitivity and specificity (75.4% and 100%, respectively). Regarding the ability to distinguish specific APD, sensitivities were 81% for MSA P, 77% for MSA C, 23% for PSP, and 54.5% for DLB. Dual phase F 18 FP CIT PET imaging is useful in demonstrating striatal DAT loss in neurodegenerative parkinsonism, and also in differentiating APD, particularly MSA, from PD.

  2. High-resolution acoustic imaging at low frequencies using 3D-printed metamaterials

    Directory of Open Access Journals (Sweden)

    S. Laureti

    2016-12-01

    Full Text Available An acoustic metamaterial has been constructed using 3D printing. It contained an array of air-filled channels, whose size and shape could be varied within the design and manufacture process. In this paper we analyze both numerically and experimentally the properties of this polymer metamaterial structure, and demonstrate its use for the imaging of a sample with sub-wavelength dimensions in the audible frequency range.

  3. Acoustic richness modulates the neural networks supporting intelligible speech processing.

    Science.gov (United States)

    Lee, Yune-Sang; Min, Nam Eun; Wingfield, Arthur; Grossman, Murray; Peelle, Jonathan E

    2016-03-01

    The information contained in a sensory signal plays a critical role in determining what neural processes are engaged. Here we used interleaved silent steady-state (ISSS) functional magnetic resonance imaging (fMRI) to explore how human listeners cope with different degrees of acoustic richness during auditory sentence comprehension. Twenty-six healthy young adults underwent scanning while hearing sentences that varied in acoustic richness (high vs. low spectral detail) and syntactic complexity (subject-relative vs. object-relative center-embedded clause structures). We manipulated acoustic richness by presenting the stimuli as unprocessed full-spectrum speech, or noise-vocoded with 24 channels. Importantly, although the vocoded sentences were spectrally impoverished, all sentences were highly intelligible. These manipulations allowed us to test how intelligible speech processing was affected by orthogonal linguistic and acoustic demands. Acoustically rich speech showed stronger activation than acoustically less-detailed speech in a bilateral temporoparietal network with more pronounced activity in the right hemisphere. By contrast, listening to sentences with greater syntactic complexity resulted in increased activation of a left-lateralized network including left posterior lateral temporal cortex, left inferior frontal gyrus, and left dorsolateral prefrontal cortex. Significant interactions between acoustic richness and syntactic complexity occurred in left supramarginal gyrus, right superior temporal gyrus, and right inferior frontal gyrus, indicating that the regions recruited for syntactic challenge differed as a function of acoustic properties of the speech. Our findings suggest that the neural systems involved in speech perception are finely tuned to the type of information available, and that reducing the richness of the acoustic signal dramatically alters the brain's response to spoken language, even when intelligibility is high. Copyright © 2015 Elsevier

  4. Magneto-thermal-acoustic differential-frequency imaging of magnetic nanoparticle with magnetic spatial localization: a theoretical prediction

    Science.gov (United States)

    Piao, Daqing

    2017-02-01

    The magneto-thermo-acoustic effect that we predicted in 2013 refers to the generation of acoustic-pressure wave from magnetic nanoparticle (MNP) when thermally mediated under an alternating magnetic field (AMF) at a pulsed or frequency-chirped application. Several independent experimental studies have since validated magneto-thermoacoustic effect, and a latest report has discovered acoustic-wave generation from MNP at the second-harmonic frequency of the AMF when operating continuously. We propose that applying two AMFs with differing frequencies to MNP will produce acoustic-pressure wave at the summation and difference of the two frequencies, in addition to the two second-harmonic frequencies. Analysis of the specific absorption dynamics of the MNP when exposed to two AMFs of differing frequencies has shown some interesting patterns of acoustic-intensity at the multiple frequency components. The ratio of the acoustic-intensity at the summation-frequency over that of the difference-frequency is determined by the frequency-ratio of the two AMFs, but remains independent of the AMF strengths. The ratio of the acoustic-intensity at the summation- or difference-frequency over that at each of the two second-harmonic frequencies is determined by both the frequency-ratio and the field-strength-ratio of the two AMFs. The results indicate a potential strategy for localization of the source of a continuous-wave magneto-thermalacoustic signal by examining the frequency spectrum of full-field non-differentiating acoustic detection, with the field-strength ratio changed continuously at a fixed frequency-ratio. The practicalities and challenges of this magnetic spatial localization approach for magneto-thermo-acoustic imaging using a simple envisioned set of two AMFs arranged in parallel to each other are discussed.

  5. Imaging tumor endothelial marker 8 using an 18F-labeled peptide

    International Nuclear Information System (INIS)

    Quan, Qimeng; Yang, Min; Gao, Haokao; Zhu, Lei; Lin, Xin; Guo, Ning; Chen, Xiaoyuan; Zhang, Guixiang; Eden, Henry S.; Niu, Gang

    2011-01-01

    Tumor endothelial marker 8 (TEM8) has been reported to be upregulated in both tumor cells and tumor-associated endothelial cells in several cancer types. TEM8 antagonists and TEM8-targeted delivery of toxins have been developed as effective cancer therapeutics. The ability to image TEM8 expression would be of use in evaluating TEM8-targeted cancer therapy. A 13-meric peptide, KYNDRLPLYISNP (QQM), identified from the small loop in domain IV of protective antigen of anthrax toxin was evaluated for TEM8 binding and labeled with 18 F for small-animal PET imaging in both UM-SCC1 head-and-neck cancer and MDA-MB-435 melanoma models. A modified ELISA showed that QQM peptide bound specifically to the extracellular vWA domain of TEM8 with an IC 50 value of 304 nM. Coupling 4-nitrophenyl 2- 18 F-fluoropropionate with QQM gave almost quantitative yield and a high specific activity (79.2 ± 7.4 TBq/mmol, n = 5) of 18 F-FP-QQM at the end of synthesis. 18 F-FP-QQM showed predominantly renal clearance and had significantly higher accumulation in TEM8 high-expressing UM-SCC1 tumors (2.96 ± 0.84 %ID/g at 1 h after injection) than TEM8 low-expressing MDA-MB-435 tumors (1.38 ± 0.56 %ID/g at 1 h after injection). QQM peptide bound specifically to the extracellular domain of TEM8. 18 F-FP-QQM peptide tracer would be a promising lead compound for measuring TEM8 expression. Further efforts to improve the affinity and specificity of the tracer and to increase its metabolic stability are warranted. (orig.)

  6. Fluorinated Polyurethane Scaffolds for 19F Magnetic Resonance Imaging

    NARCIS (Netherlands)

    Lammers, Twan; Mertens, Marianne E.; Schuster, Philipp; Rahimi, Khosrow; Shi, Yang; Schulz, Volkmar; Kuehne, Alexander J.C.; Jockenhoevel, Stefan; Kiessling, Fabian

    2017-01-01

    Researchers used fluorinated polyurethane scaffolds for 19F magnetic resonance imaging. They generated a novel fluorinated polymer based on thermoplastic polyurethane (19F -TPU) which possesses distinct properties rendering it suitable for fluorine-based MRI. The 19F -TPU is synthesized from a

  7. Molecular composition of vapor in the NaF-ZrF4 system

    International Nuclear Information System (INIS)

    Korenev, Yu.M.; Sidorov, L.N.; Rykov, A.N.; Novoselova, A.V.

    1980-01-01

    The NaF-ZrF 4 system is studied. It is established that Na 2 ZrF 6 , NaZrF 5 , (NaZrF 5 ) 2 , NaZr 2 F 9 complex molecules are present in the saturated vapor alongside with pure components. Partial pressures of all vapor components are determined. The values of partial pressure and evaporation heat have been used to calculate the vapor composition above the system; T-x and P-T projections of the phase diagram of the NaF-ZrF 4 system are plotted

  8. Spectroscopic study of the interaction of Nd+3 with amino acids: phenomenological 4f-4f intensity parameters

    International Nuclear Information System (INIS)

    Jerico, Soraya; Carubelli, Celia R.; Massabni, Ana M.G.; Stucchi, Elizabeth B.; Leite, Sergio R. de A.; Malta, Oscar

    1998-01-01

    We have studied behaviour of the phenomenological 4f-4f intensity parameters in compounds of the Nd 3+ ion with glycine, L-aspartic acid, L-glutamic acid, L-histidine, DL-malic acid and Aspartame TM in aqueous solution, as function of the pK values and partial charges on the oxygens of the carboxylate groups of these molecules. The results are discussed and qualitatively interpreted in terms of the forced electric dipole and dynamic coupling mechanisms of the 4f-4f intensities, thus indicating that the forced electric dipole mechanism is dominant. (author)

  9. PET imaging of angiogenesis after myocardial infarction/reperfusion using a one-step labeled integrin-targeted tracer {sup 18}F-AlF-NOTA-PRGD2

    Energy Technology Data Exchange (ETDEWEB)

    Gao, Haokao [The Fourth Military Medical University, Department of Cardiology, Xijing Hospital, Xi' an (China); National Institute of Biomedical Imaging and Bioengineering (NIBIB), National Institutes of Health (NIH), Laboratory of Molecular Imaging and Nanomedicine (LOMIN), Bethesda, MD (United States); Lang, Lixin; Guo, Ning; Quan, Qimeng; Hu, Shuo; Kiesewetter, Dale O.; Niu, Gang; Chen, Xiaoyuan [National Institute of Biomedical Imaging and Bioengineering (NIBIB), National Institutes of Health (NIH), Laboratory of Molecular Imaging and Nanomedicine (LOMIN), Bethesda, MD (United States); Cao, Feng [The Fourth Military Medical University, Department of Cardiology, Xijing Hospital, Xi' an (China)

    2012-04-15

    The {alpha}{sub v}{beta}{sub 3} integrin represents a potential target for noninvasive imaging of angiogenesis. The purpose of this study was to evaluate a novel one-step labeled integrin {alpha}{sub v}{beta}{sub 3}-targeting positron emission tomography (PET) probe, {sup 18}F-AlF-NOTA-PRGD2, for angiogenesis imaging in a myocardial infarction/reperfusion (MI/R) animal model. Male Sprague-Dawley rats underwent 45-min transient left coronary artery occlusion followed by reperfusion. The myocardial infarction was confirmed by ECG, {sup 18}F-fluorodeoxyglucose (FDG) imaging, and cardiac ultrasound. In vivo PET imaging was used to determine myocardial uptake of {sup 18}F-AlF-NOTA-PRGD2 at different time points following reperfusion. The control peptide RAD was labeled with a similar procedure and used to confirm the specificity. Ex vivo autoradiographic analysis and CD31/CD61 double immunofluorescence staining were performed to validate the PET results. Myocardial origin of the {sup 18}F-AlF-NOTA-PRGD2 accumulation was confirmed by {sup 18}F-FDG and autoradiography. PET imaging demonstrated increased focal accumulation of {sup 18}F-AlF-NOTA-PRGD2 in the infarcted area which started at day 3 (0.28 {+-} 0.03%ID/g, p < 0.05) and peaked between 1 and 3 weeks (0.59 {+-} 0.16 and 0.55 {+-} 0.13%ID/g, respectively). The focal accumulation decreased but still kept at a higher level than the sham group after 4 months of reperfusion (0.31 {+-} 0.01%ID/g, p < 0.05). Pretreatment with unlabeled arginine-glycine-aspartic acid (RGD) peptide significantly decreased tracer uptake, indicating integrin specificity of this tracer. At 1 week after MI/R, uptake of the control tracer {sup 18}F-AlF-NOTA-RAD that does not bind to integrin, in the infarcted area, was only 0.21 {+-} 0.01%ID/g. Autoradiographic imaging showed the same trend of uptake in the myocardial infarction area. The time course of focal tracer uptake was consistent with the pattern of vascular density and integrin {beta

  10. Multidirectional seismo-acoustic wavefield of strombolian explosions at Yasur, Vanuatu using a broadband seismo-acoustic network, infrasound arrays, and infrasonic sensors on tethered balloons

    Science.gov (United States)

    Matoza, R. S.; Jolly, A. D.; Fee, D.; Johnson, R.; Kilgour, G.; Christenson, B. W.; Garaebiti, E.; Iezzi, A. M.; Austin, A.; Kennedy, B.; Fitzgerald, R.; Key, N.

    2016-12-01

    Seismo-acoustic wavefields at volcanoes contain rich information on shallow magma transport and subaerial eruption processes. Acoustic wavefields from eruptions are predicted to be directional, but sampling this wavefield directivity is challenging because infrasound sensors are usually deployed on the ground surface. We attempt to overcome this observational limitation using a novel deployment of infrasound sensors on tethered balloons in tandem with a suite of dense ground-based seismo-acoustic, geochemical, and eruption imaging instrumentation. We present preliminary results from a field experiment at Yasur Volcano, Vanuatu from July 26th to August 4th 2016. Our observations include data from a temporary network of 11 broadband seismometers, 6 single infrasonic microphones, 7 small-aperture 3-element infrasound arrays, 2 infrasound sensor packages on tethered balloons, an FTIR, a FLIR, 2 scanning Flyspecs, and various visual imaging data. An introduction to the dataset and preliminary analysis of the 3D seismo-acoustic wavefield and source process will be presented. This unprecedented dataset should provide a unique window into processes operating in the shallow magma plumbing system and their relation to subaerial eruption dynamics.

  11. Ultrasonic phased array with surface acoustic wave for imaging cracks

    Directory of Open Access Journals (Sweden)

    Yoshikazu Ohara

    2017-06-01

    Full Text Available To accurately measure crack lengths, we developed a real-time surface imaging method (SAW PA combining an ultrasonic phased array (PA with a surface acoustic wave (SAW. SAW PA using a Rayleigh wave with a high sensitivity to surface defects was implemented for contact testing using a wedge with the third critical angle that allows the Rayleigh wave to be generated. Here, to realize high sensitivity imaging, SAW PA was optimized in terms of the wedge and the imaging area. The improved SAW PA was experimentally demonstrated using a fatigue crack specimen made of an aluminum alloy. For further verification in more realistic specimens, SAW PA was applied to stainless-steel specimens with a fatigue crack and stress corrosion cracks (SCCs. The fatigue crack was visualized with a high signal-to-noise ratio (SNR and its length was measured with a high accuracy of better than 1 mm. The SCCs generated in the heat-affected zones (HAZs of a weld were successfully visualized with a satisfactory SNR, although responses at coarse grains appeared throughout the imaging area. The SCC lengths were accurately measured. The imaging results also precisely showed complicated distributions of SCCs, which were in excellent agreement with the optically observed distributions.

  12. Near-Field Acoustic Power Level Analysis of F31/A31 Open Rotor Model at Simulated Cruise Conditions, Technical Report II

    Science.gov (United States)

    Sree, Dave

    2015-01-01

    Near-field acoustic power level analysis of F31A31 open rotor model has been performed to determine its noise characteristics at simulated cruise flight conditions. The non-proprietary parts of the test data obtained from experiments in the 8x6 supersonic wind tunnel were provided by NASA-Glenn Research Center. The tone and broadband components of total noise have been separated from raw test data by using a new data analysis tool. Results in terms of sound pressure levels, acoustic power levels, and their variations with rotor speed, freestream Mach number, and input shaft power, with different blade-pitch setting angles at simulated cruise flight conditions, are presented and discussed. Empirical equations relating models acoustic power level and input shaft power have been developed. The near-field acoustic efficiency of the model at simulated cruise conditions is also determined. It is hoped that the results presented in this work will serve as a database for comparison and improvement of other open rotor blade designs and also for validating open rotor noise prediction codes.

  13. A line array based near field imaging technique for characterising acoustical properties of elongated targets

    NARCIS (Netherlands)

    Driessen, F.P.G.

    1995-01-01

    With near field imaging techniques the acoustical pressure waves at distances other than the recorded can be calculated. Normally, acquisition on a two dimensional plane is necessary and extrapolation is performed by a Rayleigh integral. A near field single line instead of two dimensional plane

  14. Preliminary study of copper oxide nanoparticles acoustic and magnetic properties for medical imaging

    Science.gov (United States)

    Perlman, Or; Weitz, Iris S.; Azhari, Haim

    2015-03-01

    The implementation of multimodal imaging in medicine is highly beneficial as different physical properties may provide complementary information, augmented detection ability, and diagnosis verification. Nanoparticles have been recently used as contrast agents for various imaging modalities. Their significant advantage over conventional large-scale contrast agents is the ability of detection at early stages of the disease, being less prone to obstacles on their path to the target region, and possible conjunction to therapeutics. Copper ions play essential role in human health. They are used as a cofactor for multiple key enzymes involved in various fundamental biochemistry processes. Extremely small size copper oxide nanoparticles (CuO-NPs) are readily soluble in water with high colloidal stability yielding high bioavailability. The goal of this study was to examine the magnetic and acoustic characteristics of CuO-NPs in order to evaluate their potential to serve as contrast imaging agent for both MRI and ultrasound. CuO-NPs 7nm in diameter were synthesized by hot solution method. The particles were scanned using a 9.4T MRI and demonstrated a concentration dependent T1 relaxation time shortening phenomenon. In addition, it was revealed that CuO-NPs can be detected using the ultrasonic B-scan imaging. Finally, speed of sound based ultrasonic computed tomography was applied and showed that CuO-NPs can be clearly imaged. In conclusion, the preliminary results obtained, positively indicate that CuO-NPs may be imaged by both MRI and ultrasound. The results motivate additional in-vivo studies, in which the clinical utility of fused images derived from both modalities for diagnosis improvement will be studied.

  15. Prediction of standard-dose brain PET image by using MRI and low-dose brain [{sup 18}F]FDG PET images

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Jiayin [School of Electronics Engineering, Huaihai Institute of Technology, Lianyungang, Jiangsu 222005, China and IDEA Laboratory, Department of Radiology and BRIC, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599 (United States); Gao, Yaozong [IDEA Laboratory, Department of Radiology and BRIC, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599 and Department of Computer Science, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599 (United States); Shi, Feng [IDEA Laboratory, Department of Radiology and BRIC, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599 (United States); Lalush, David S. [Joint UNC-NCSU Department of Biomedical Engineering, North Carolina State University, Raleigh, North Carolina 27695 (United States); Lin, Weili [MRI Laboratory, Department of Radiology and BRIC, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599 (United States); Shen, Dinggang, E-mail: dgshen@med.unc.edu [IDEA Laboratory, Department of Radiology and BRIC, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599 and Department of Brain and Cognitive Engineering, Korea University, Seoul 136-713 (Korea, Republic of)

    2015-09-15

    Purpose: Positron emission tomography (PET) is a nuclear medical imaging technology that produces 3D images reflecting tissue metabolic activity in human body. PET has been widely used in various clinical applications, such as in diagnosis of brain disorders. High-quality PET images play an essential role in diagnosing brain diseases/disorders. In practice, in order to obtain high-quality PET images, a standard-dose radionuclide (tracer) needs to be used and injected into a living body. As a result, it will inevitably increase the patient’s exposure to radiation. One solution to solve this problem is predicting standard-dose PET images using low-dose PET images. As yet, no previous studies with this approach have been reported. Accordingly, in this paper, the authors propose a regression forest based framework for predicting a standard-dose brain [{sup 18}F]FDG PET image by using a low-dose brain [{sup 18}F]FDG PET image and its corresponding magnetic resonance imaging (MRI) image. Methods: The authors employ a regression forest for predicting the standard-dose brain [{sup 18}F]FDG PET image by low-dose brain [{sup 18}F]FDG PET and MRI images. Specifically, the proposed method consists of two main steps. First, based on the segmented brain tissues (i.e., cerebrospinal fluid, gray matter, and white matter) in the MRI image, the authors extract features for each patch in the brain image from both low-dose PET and MRI images to build tissue-specific models that can be used to initially predict standard-dose brain [{sup 18}F]FDG PET images. Second, an iterative refinement strategy, via estimating the predicted image difference, is used to further improve the prediction accuracy. Results: The authors evaluated their algorithm on a brain dataset, consisting of 11 subjects with MRI, low-dose PET, and standard-dose PET images, using leave-one-out cross-validations. The proposed algorithm gives promising results with well-estimated standard-dose brain [{sup 18}F]FDG PET

  16. Prediction of standard-dose brain PET image by using MRI and low-dose brain ["1"8F]FDG PET images

    International Nuclear Information System (INIS)

    Kang, Jiayin; Gao, Yaozong; Shi, Feng; Lalush, David S.; Lin, Weili; Shen, Dinggang

    2015-01-01

    Purpose: Positron emission tomography (PET) is a nuclear medical imaging technology that produces 3D images reflecting tissue metabolic activity in human body. PET has been widely used in various clinical applications, such as in diagnosis of brain disorders. High-quality PET images play an essential role in diagnosing brain diseases/disorders. In practice, in order to obtain high-quality PET images, a standard-dose radionuclide (tracer) needs to be used and injected into a living body. As a result, it will inevitably increase the patient’s exposure to radiation. One solution to solve this problem is predicting standard-dose PET images using low-dose PET images. As yet, no previous studies with this approach have been reported. Accordingly, in this paper, the authors propose a regression forest based framework for predicting a standard-dose brain ["1"8F]FDG PET image by using a low-dose brain ["1"8F]FDG PET image and its corresponding magnetic resonance imaging (MRI) image. Methods: The authors employ a regression forest for predicting the standard-dose brain ["1"8F]FDG PET image by low-dose brain ["1"8F]FDG PET and MRI images. Specifically, the proposed method consists of two main steps. First, based on the segmented brain tissues (i.e., cerebrospinal fluid, gray matter, and white matter) in the MRI image, the authors extract features for each patch in the brain image from both low-dose PET and MRI images to build tissue-specific models that can be used to initially predict standard-dose brain ["1"8F]FDG PET images. Second, an iterative refinement strategy, via estimating the predicted image difference, is used to further improve the prediction accuracy. Results: The authors evaluated their algorithm on a brain dataset, consisting of 11 subjects with MRI, low-dose PET, and standard-dose PET images, using leave-one-out cross-validations. The proposed algorithm gives promising results with well-estimated standard-dose brain ["1"8F]FDG PET image and substantially

  17. Mapping the geometry of the F4 group

    International Nuclear Information System (INIS)

    Bernardoni, Fabio; Cacciatori, Sergio L.; Scotti, Antonio; Cerchiai, Bianca L.

    2007-01-01

    In this paper, we present a construction of the compact form of the exceptional Lie group F4 by exponentiating the corresponding Lie algebra f4. We realize F4 as the automorphisms group of the exceptional Jordan algebra, whose elements are 3 x 3 Hermitian matrices with octonionic entries. We use a parametrization which generalizes the Euler angles for SU(2) and is based on the fibration of F4 via a Spin(9) subgroup as a fiber. This technique allows us to determine an explicit expression for the Haar invariant measure on the F4 group manifold. Apart from shedding light on the structure of F4 and its coset manifold OP2 = F4/Spin(9), the octonionic projective plane, these results are a prerequisite for the study of E6, of which F4 is a (maximal) subgroup

  18. Experimental demonstration of passive acoustic imaging in the human skull cavity using CT-based aberration corrections.

    Science.gov (United States)

    Jones, Ryan M; O'Reilly, Meaghan A; Hynynen, Kullervo

    2015-07-01

    Experimentally verify a previously described technique for performing passive acoustic imaging through an intact human skull using noninvasive, computed tomography (CT)-based aberration corrections Jones et al. [Phys. Med. Biol. 58, 4981-5005 (2013)]. A sparse hemispherical receiver array (30 cm diameter) consisting of 128 piezoceramic discs (2.5 mm diameter, 612 kHz center frequency) was used to passively listen through ex vivo human skullcaps (n = 4) to acoustic emissions from a narrow-band fixed source (1 mm diameter, 516 kHz center frequency) and from ultrasound-stimulated (5 cycle bursts, 1 Hz pulse repetition frequency, estimated in situ peak negative pressure 0.11-0.33 MPa, 306 kHz driving frequency) Definity™ microbubbles flowing through a thin-walled tube phantom. Initial in vivo feasibility testing of the method was performed. The performance of the method was assessed through comparisons to images generated without skull corrections, with invasive source-based corrections, and with water-path control images. For source locations at least 25 mm from the inner skull surface, the modified reconstruction algorithm successfully restored a single focus within the skull cavity at a location within 1.25 mm from the true position of the narrow-band source. The results obtained from imaging single bubbles are in good agreement with numerical simulations of point source emitters and the authors' previous experimental measurements using source-based skull corrections O'Reilly et al. [IEEE Trans. Biomed. Eng. 61, 1285-1294 (2014)]. In a rat model, microbubble activity was mapped through an intact human skull at pressure levels below and above the threshold for focused ultrasound-induced blood-brain barrier opening. During bursts that led to coherent bubble activity, the location of maximum intensity in images generated with CT-based skull corrections was found to deviate by less than 1 mm, on average, from the position obtained using source-based corrections. Taken

  19. Controlling sound with acoustic metamaterials

    DEFF Research Database (Denmark)

    Cummer, Steven A. ; Christensen, Johan; Alù, Andrea

    2016-01-01

    Acoustic metamaterials can manipulate and control sound waves in ways that are not possible in conventional materials. Metamaterials with zero, or even negative, refractive index for sound offer new possibilities for acoustic imaging and for the control of sound at subwavelength scales....... The combination of transformation acoustics theory and highly anisotropic acoustic metamaterials enables precise control over the deformation of sound fields, which can be used, for example, to hide or cloak objects from incident acoustic energy. Active acoustic metamaterials use external control to create......-scale metamaterial structures and converting laboratory experiments into useful devices. In this Review, we outline the designs and properties of materials with unusual acoustic parameters (for example, negative refractive index), discuss examples of extreme manipulation of sound and, finally, provide an overview...

  20. Reconstruction of an acoustic pressure field in a resonance tube by particle image velocimetry.

    Science.gov (United States)

    Kuzuu, K; Hasegawa, S

    2015-11-01

    A technique for estimating an acoustic field in a resonance tube is suggested. The estimation of an acoustic field in a resonance tube is important for the development of the thermoacoustic engine, and can be conducted employing two sensors to measure pressure. While this measurement technique is known as the two-sensor method, care needs to be taken with the location of pressure sensors when conducting pressure measurements. In the present study, particle image velocimetry (PIV) is employed instead of a pressure measurement by a sensor, and two-dimensional velocity vector images are extracted as sequential data from only a one- time recording made by a video camera of PIV. The spatial velocity amplitude is obtained from those images, and a pressure distribution is calculated from velocity amplitudes at two points by extending the equations derived for the two-sensor method. By means of this method, problems relating to the locations and calibrations of multiple pressure sensors are avoided. Furthermore, to verify the accuracy of the present method, the experiments are conducted employing the conventional two-sensor method and laser Doppler velocimetry (LDV). Then, results by the proposed method are compared with those obtained with the two-sensor method and LDV.

  1. Micromachined silicon acoustic delay line with 3D-printed micro linkers and tapered input for improved structural stability and acoustic directivity

    International Nuclear Information System (INIS)

    Cho, Y; Kumar, A; Xu, S; Zou, J

    2016-01-01

    Recent studies have shown that micromachined silicon acoustic delay lines can provide a promising solution to achieve real-time photoacoustic tomography without the need for complex transducer arrays and data acquisition electronics. To achieve deeper imaging depth and wider field of view, a longer delay time and therefore delay length are required. However, as the length of the delay line increases, it becomes more vulnerable to structural instability due to reduced mechanical stiffness. In this paper, we report the design, fabrication, and testing of a new silicon acoustic delay line enhanced with 3D printed polymer micro linker structures. First, mechanical deformation of the silicon acoustic delay line (with and without linker structures) under gravity was simulated by using finite element method. Second, the acoustic crosstalk and acoustic attenuation caused by the polymer micro linker structures were evaluated with both numerical simulation and ultrasound transmission testing. The result shows that the use of the polymer micro linker structures significantly improves the structural stability of the silicon acoustic delay lines without creating additional acoustic attenuation and crosstalk. In addition, the improvement of the acoustic acceptance angle of the silicon acoustic delay lines was also investigated to better suppress the reception of unwanted ultrasound signals outside of the imaging plane. These two improvements are expected to provide an effective solution to eliminate current limitations on the achievable acoustic delay time and out-of-plane imaging resolution of micromachined silicon acoustic delay line arrays. (paper)

  2. Density-near-zero using the acoustically induced transparency of a Fano acoustic resonator

    KAUST Repository

    Elayouch, A.

    2017-01-05

    We report experimental results of near-zero mass density involving an acoustic metamaterial supporting Fano resonance. For this, we designed and fabricated an acoustic resonator with two closely coupled modes and measured its transmission properties. Our study reveals that the phenomenon of acoustically induced transparency is accompanied by an effect of near-zero density. Indeed, the dynamic effective parameters obtained from experimental data show the presence of a frequency band where the effective mass density is close to zero, with high transmission levels reaching 0.7. Furthermore, we demonstrate that such effective parameters lead to wave guiding in a 90-degrees-bent channel. This kind of acoustic metamaterial can, therefore, give rise to acoustic functions like controlling the wavefront, which may lead to very promising applications in acoustic cloacking or imaging.

  3. Enlarging the angle of view in Michelson-interferometer-based shearography by embedding a 4f system.

    Science.gov (United States)

    Wu, Sijin; He, Xiaoyuan; Yang, Lianxiang

    2011-07-20

    Digital shearography based on Michelson interferometers suffers from the disadvantage of a small angle of view due to the structure. We demonstrate a novel digital shearography system with a large angle of view. In the optical arrangement, the imaging lens is in front of the Michelson interferometer rather than behind it as in traditional digital shearography. Thus, the angle of view is no longer limited by the Michelson interferometer. The images transmitting between the separate lens and camera are accomplished by a 4f system in the new style of shearography. The influences of the 4f system on shearography are also discussed. © 2011 Optical Society of America

  4. Seed-mediated synthesis of NaY F4:Y b, Er/NaGdF4 nanocrystals with improved upconversion fluorescence and MR relaxivity

    International Nuclear Information System (INIS)

    Guo Hai; Li Zhengquan; Qian Haisheng; Hu Yong; Muhammad, Idris Niagara

    2010-01-01

    Rational combination of different functional lanthanide materials within a single nanocrystal presents a feasible way to develop a multifunctional nanoplatform for various biomedical applications. The conventional methods of synthesizing and integrating two kinds of material together generally involve laborious procedures, whilst codoping different functional ions inside a single lanthanide nanocrystal usually results in a decrease in both its fluorescence and its magnetic resonance relaxivity. Here, we present a seed-mediated synthetic route to prepare core-shell structured NaY F 4 :Y b, Er/NaGdF 4 nanocrystals. Epitaxial growth of a gadolinium layer on an upconversion lanthanide seed not only improves its upconversion fluorescence, but also creates a paramagnetic shell with high magnetic resonance relaxivity. The prepared nanocrystals are uniform in size, stable in water and easy for conjugation after modification, which may have the potential to serve as a versatile imaging tool for smart detection or diagnosis in future biomedical engineering.

  5. Communication Acoustics

    DEFF Research Database (Denmark)

    Blauert, Jens

    Communication Acoustics deals with the fundamentals of those areas of acoustics which are related to modern communication technologies. Due to the advent of digital signal processing and recording in acoustics, these areas have enjoyed an enormous upswing during the last 4 decades. The book...... the book a source of valuable information for those who want to improve or refresh their knowledge in the field of communication acoustics - and to work their way deeper into it. Due to its interdisciplinary character Communication Acoustics is bound to attract readers from many different areas, such as......: acoustics, cognitive science, speech science, and communication technology....

  6. 4- {sup 18}F]fluoroarylalkylethers via an improved synthesis of n.c.a. 4- {sup 18}F]fluorophenol

    Energy Technology Data Exchange (ETDEWEB)

    Ludwig, Thomas; Ermert, Johannes E-mail: j.ermert@fz-juelich.de; Coenen, Heinz H

    2002-02-01

    This paper describes the improved synthesis of n.c.a. 4- {sup 18}F]fluorophenol for the preparation of {sup 18}F-labeled alkylarylethers. Nucleophilic fluorination of substituted benzophenone derivatives yielded n.c.a. 4- {sup 18}F]fluoro-4'-substituted benzophenones with 80- 90 % RCY, which were converted to benzoic acid phenylesters by treatment with peracetic acid. Strong electron-withdrawing substituents like nitro, cyano and trifluoromethyl favor a fluorophenyl-to-oxygen migration resulting in the formation of corresponding benzoic acid fluorophenylesters. N.c.a. {sup 18}F]fluorophenol is almost quantitatively formed after hydrolysis and can easily be converted with alkylhalides into n.c.a. {sup 18}F]fluoroarylalkylethers.

  7. Initial results of hypoxia imaging using 1-α-d-(5-deoxy-5-[18F]-fluoroarabinofuranosyl)-2-nitroimidazole (18F-FAZA)

    International Nuclear Information System (INIS)

    Postema, Ernst J.; McEwan, Alexander J.B.; Riauka, Terence A.; Kumar, Piyush; Richmond, Dacia A.; Abrams, Douglas N.; Wiebe, Leonard I.

    2009-01-01

    Tumour hypoxia is thought to play a significant role in the outcome of solid tumour therapy. Positron emission tomography (PET) is the best-validated noninvasive technique able to demonstrate the presence of hypoxia in vivo. The locally developed PET tracer for imaging hypoxia, 1-α-d-(5-deoxy-5-[ 18 F]-fluoroarabinofuranosyl)-2-nitroimidazole ( 18 F-FAZA), has been shown to accumulate in experimental models of tumour hypoxia and to clear rapidly from the circulation and nonhypoxic tissues. The safety and general biodistribution patterns of this radiopharmaceutical in patients with squamous cell carcinoma of the head and neck (HNSCC), small-cell lung cancer (SCLC) or non-small-cell lung cancer (NSCLC), malignant lymphoma, and high-grade gliomas, were demonstrated in this study. Patients with known primary or suspected metastatic HNSCC, SCLC or NSCLC, malignant lymphoma or high-grade gliomas were dosed with 5.2 MBq/kg of 18 F-FAZA, then scanned 2-3 h after injection using a PET or PET/CT scanner. Images were interpreted by three experienced nuclear medicine physicians. The location and relative uptake scores (graded 0 to 4) of normal and abnormal 18 F-FAZA biodistribution patterns, the calculated tumour-to-background (T/B) ratio, and the maximum standardized uptake value were recorded. Included in the study were 50 patients (32 men, 18 women). All seven patients with high-grade gliomas showed very high uptake of 18 F-FAZA in the primary tumour. In six out of nine patients with HNSCC, clear uptake of 18 F-FAZA was observed in the primary tumour and/or the lymph nodes in the neck. Of the 21 lymphoma patients (15 with non-Hodgkin's lymphoma and 6 with Hodgkin's disease), 3 demonstrated moderate lymphoma-related uptake. Of the 13 lung cancer patients (12 NSCLC, 1 SCLC), 7 had increased 18 F-FAZA uptake in the primary lung tumour. No side effects of the administration of 18 F-FAZA were observed. This study suggests that 18 F-FAZA may be a very useful radiopharmaceutical

  8. Overview of image reconstruction

    International Nuclear Information System (INIS)

    Marr, R.B.

    1980-04-01

    Image reconstruction (or computerized tomography, etc.) is any process whereby a function, f, on R/sup n/ is estimated from empirical data pertaining to its integrals, ∫f(x) dx, for some collection of hyperplanes of dimension k < n. The paper begins with background information on how image reconstruction problems have arisen in practice, and describes some of the application areas of past or current interest; these include radioastronomy, optics, radiology and nuclear medicine, electron microscopy, acoustical imaging, geophysical tomography, nondestructive testing, and NMR zeugmatography. Then the various reconstruction algorithms are discussed in five classes: summation, or simple back-projection; convolution, or filtered back-projection; Fourier and other functional transforms; orthogonal function series expansion; and iterative methods. Certain more technical mathematical aspects of image reconstruction are considered from the standpoint of uniqueness, consistency, and stability of solution. The paper concludes by presenting certain open problems. 73 references

  9. Small Animal [18F]FDG PET Imaging for Tumor Model Study

    International Nuclear Information System (INIS)

    Woo, Sang Keun; Kim, Kyeong Min; Cheon, Gi Jeong

    2008-01-01

    PET allows non-invasive, quantitative and repetitive imaging of biological function in living animals. Small animal PET imaging with [ 18 F]FDG has been successfully applied to investigation of metabolism, receptor, ligand interactions, gene expression, adoptive cell therapy and somatic gene therapy. Experimental condition of animal handling impacts on the biodistribution of [ 18 F]FDG in small animal study. The small animal PET and CT images were registered using the hardware fiducial markers and small animal contour point. Tumor imaging in small animal with small animal [ 18 F]FDG PET should be considered fasting, warming, and isoflurane anesthesia level. Registered imaging with small animal PET and CT image could be useful for the detection of tumor. Small animal experimental condition of animal handling and registration method will be of most importance for small lesion detection of metastases tumor model

  10. Thrombus imaging with indium-111 and iodine-131-labeled fibrin-specific monoclonal antibody and its F(ab')2 and Fab fragments

    International Nuclear Information System (INIS)

    Rosebrough, S.F.; Grossman, Z.D.; McAfee, J.G.

    1988-01-01

    We have previously reported successful imaging of fresh (2-4 hr old) and aged (1-5 days old) canine thrombi with 131 I-labeled intact monoclonal antibody (MAb) specific for fibrin. We now report thrombus imaging with 131 I-labeled F(ab')2 and Fab and 111 In-labeled intact MAb, F(ab')2, and Fab. Indium-111-labeled F(ab')2 proved to be the best imaging agent due to less nonspecific binding in the liver than whole IgG. Image quality was improved by the higher administered dose permissible with 111 In and its better physical characteristics for imaging, compared to 131 I. Immunofluorescence of fresh human histologic sections showed intact MAb and F(ab')2 binding to thrombi, pulmonary emboli, and atherosclerotic plaques, strengthening the feasibility of clinical thrombus imaging

  11. Acoustic emission from polycrystalline graphites

    International Nuclear Information System (INIS)

    Ioka, I.; Yoda, S.; Oku, T.; Miyamoto, Y.

    1987-01-01

    Acoustic emission was monitored from polycrystalline graphites with different microstructure (pore size and pore volume) subjected to compressive loading. The graphites used in this study comprised five brands, that is, PGX, ISEM-1, IG-11, IG-15, and ISO-88. A root mean square (RMS) voltage and event counts of acoustic emission for graphites were measured during compressive loading. The acoustic emission was measured using a computed-based data acquisition and analysis system. The graphites were first deformed up to 80 % of the average fracture stress, then unloaded and reloaded again until the fracture occured. During the first loading, the change in RMS voltage for acoustic emission was detected from the initial stage. During the unloading, the RMS voltage became zero level as soon as the applied stress was released and then gradually rose to a peak and declined. The behavior indicated that the reversed plastic deformation occured in graphites. During the second loading, the RMS voltage gently increased until the applied stress exceeded the maximum stress of the first loading; there is no Kaiser effect in the graphites. A bicrystal model could give a reasonable explanation of this results. The empirical equation between the ratio of σ AE to σ f and σ f was obtained. It is considered that the detection of microfracture by the acoustic emission technique is effective in macrofracture prediction of polycrystalline graphites. (author)

  12. Synthesis and biological evaluation of [{sup 18}F]tetrafluoroborate: a PET imaging agent for thyroid disease and reporter gene imaging of the sodium/iodide symporter

    Energy Technology Data Exchange (ETDEWEB)

    Jauregui-Osoro, Maite; Sunassee, Kavitha; Weeks, Amanda J.; Berry, David J.; Paul, Rowena L.; Cleij, Marcel; O' Doherty, Michael J.; Marsden, Paul K.; Szanda, Istvan; Blower, Philip J. [King' s College London, Division of Imaging Sciences, London (United Kingdom); Banga, Jasvinder Paul [King' s College London, Division of Cell and Gene Based Therapy, London (United Kingdom); Clarke, Susan E.M.; Ballinger, James R. [Guy' s and St Thomas' NHS Trust, Department of Nuclear Medicine, London (United Kingdom); Cheng, Sheue-Yann [National Cancer Institute, Laboratory of Molecular Biology, Bethesda (United States)

    2010-11-15

    The human sodium/iodide symporter (hNIS) is a well-established target in thyroid disease and reporter gene imaging using gamma emitters {sup 123}I-iodide, {sup 131}I-iodide and {sup 99m}Tc-pertechnetate. However, no PET imaging agent is routinely available. The aim of this study was to prepare and evaluate {sup 18}F-labelled tetrafluoroborate ([{sup 18}F]TFB) for PET imaging of hNIS. [{sup 18}F]TFB was prepared by isotopic exchange of BF{sub 4} {sup -} with [{sup 18}F]fluoride in hot hydrochloric acid and purified using an alumina column. Its identity, purity and stability in serum were determined by HPLC, thin-layer chromatography (TLC) and mass spectrometry. Its interaction with NIS was assessed in vitro using FRTL-5 rat thyroid cells, with and without stimulation by thyroid-stimulating hormone (TSH), in the presence and absence of perchlorate. Biodistribution and PET imaging studies were performed using BALB/c mice, with and without perchlorate inhibition. [{sup 18}F]TFB was readily prepared with specific activity of 10 GBq/mg. It showed rapid accumulation in FRTL-5 cells that was stimulated by TSH and inhibited by perchlorate, and rapid specific accumulation in vivo in thyroid (SUV = 72 after 1 h) and stomach that was inhibited 95% by perchlorate. [{sup 18}F]TFB is an easily prepared PET imaging agent for rodent NIS and should be evaluated for hNIS PET imaging in humans. (orig.)

  13. SU-D-201-03: Imaging Cellular Pharmacokinetics of 18F-FDG in Inflammatory/Stem Cells

    Energy Technology Data Exchange (ETDEWEB)

    Zaman, R; Tuerkcan, S; Mahmoudi, M; Toshinobu, T; Kosuge, H; Yang, P; Chin, F; McConnell, M; Xing, L [Stanford University School of Medicine, Stanford, CA (United States)

    2015-06-15

    Purpose: Atherosclerosis is a progressive inflammatory condition that underlies coronary artery disease (CAD)—the leading cause of death in the USA. Thus, understating the metabolism of inflammatory cells can be a valuable tool for investigating CAD. To the best of our knowledge, we are the first to successfully investigate the pharmacokinetics of [18F]fluoro-deoxyglucose (18F-FDG) uptake in a single macrophages and compared with induced pluripotent stem cells (iPSCs) and mesenchymal stem cells (MSCs) with a novel imaging technique, radioluminescence microscopy, initially developed for cancer imaging. Methods: Live cells were cultured sparsely on Matrigel in a glass-bottom dish and starved for 1 hour before incubation with 250 microCi of 18F-FDG for 45 minutes. Excess radiotracer was removed using DMEM medium without glucose. Before imaging, DMEM (1 mL) was added to the cell culture and a 100 microm-thin CdWO4 scintillator plate was placed on top of the cells. Light produced following beta decay was imaged with a highly sensitive inverted microscope (LV200, Olympus) fitted with a 40x/1.3 high-NA oil objective, and an EM-CCD camera. The images were collected over 18,000 frames with 4×4 binning (1200 MHz EM Gain, 300ms exposure). Custom-written software was developed in MATLAB for image processing (Figure 1). For statistical analysis 10 different region-of-interests (ROIs) were selected for each cell type. Results: Figures 2A–2B show bright-field/fusion images for all three different cell types. The relationship between cell-to-cell comparisons was found to be linear for macrophages unlike iPSCs and MSCs, which were best fitted with moving or rolling average (Figure 2C). The average observed decay of 18F-FDG in a single cell of MSCs per second (0.067) was 20% and 36% higher compared to iPSCs (0.054) and macrophages (0.043), respectively (Figure 2D). Conclusion: MSCs was found to be 2–3x more sensitive to glucose molecule despite constant parameters for each

  14. SU-D-201-03: Imaging Cellular Pharmacokinetics of 18F-FDG in Inflammatory/Stem Cells

    International Nuclear Information System (INIS)

    Zaman, R; Tuerkcan, S; Mahmoudi, M; Toshinobu, T; Kosuge, H; Yang, P; Chin, F; McConnell, M; Xing, L

    2015-01-01

    Purpose: Atherosclerosis is a progressive inflammatory condition that underlies coronary artery disease (CAD)—the leading cause of death in the USA. Thus, understating the metabolism of inflammatory cells can be a valuable tool for investigating CAD. To the best of our knowledge, we are the first to successfully investigate the pharmacokinetics of [18F]fluoro-deoxyglucose (18F-FDG) uptake in a single macrophages and compared with induced pluripotent stem cells (iPSCs) and mesenchymal stem cells (MSCs) with a novel imaging technique, radioluminescence microscopy, initially developed for cancer imaging. Methods: Live cells were cultured sparsely on Matrigel in a glass-bottom dish and starved for 1 hour before incubation with 250 microCi of 18F-FDG for 45 minutes. Excess radiotracer was removed using DMEM medium without glucose. Before imaging, DMEM (1 mL) was added to the cell culture and a 100 microm-thin CdWO4 scintillator plate was placed on top of the cells. Light produced following beta decay was imaged with a highly sensitive inverted microscope (LV200, Olympus) fitted with a 40x/1.3 high-NA oil objective, and an EM-CCD camera. The images were collected over 18,000 frames with 4×4 binning (1200 MHz EM Gain, 300ms exposure). Custom-written software was developed in MATLAB for image processing (Figure 1). For statistical analysis 10 different region-of-interests (ROIs) were selected for each cell type. Results: Figures 2A–2B show bright-field/fusion images for all three different cell types. The relationship between cell-to-cell comparisons was found to be linear for macrophages unlike iPSCs and MSCs, which were best fitted with moving or rolling average (Figure 2C). The average observed decay of 18F-FDG in a single cell of MSCs per second (0.067) was 20% and 36% higher compared to iPSCs (0.054) and macrophages (0.043), respectively (Figure 2D). Conclusion: MSCs was found to be 2–3x more sensitive to glucose molecule despite constant parameters for each

  15. Real-time contrast ultrasound muscle perfusion imaging with intermediate-power imaging coupled with acoustically durable microbubbles.

    Science.gov (United States)

    Seol, Sang-Hoon; Davidson, Brian P; Belcik, J Todd; Mott, Brian H; Goodman, Reid M; Ammi, Azzdine; Lindner, Jonathan R

    2015-06-01

    There is growing interest in limb contrast-enhanced ultrasound (CEU) perfusion imaging for the evaluation of peripheral artery disease. Because of low resting microvascular blood flow in skeletal muscle, signal enhancement during limb CEU is prohibitively low for real-time imaging. The aim of this study was to test the hypothesis that this obstacle can be overcome by intermediate- rather than low-power CEU when performed with an acoustically resilient microbubble agent. Viscoelastic properties of Definity and Sonazoid were assessed by measuring bulk modulus during incremental increases in ambient pressure to 200 mm Hg. Comparison of in vivo microbubble destruction and signal enhancement at a mechanical index (MI) of 0.1 to 0.4 was performed by sequential reduction in pulsing interval from 10 to 0.05 sec during limb CEU at 7 MHz in mice and 1.8 MHz in dogs. Destruction was also assessed by broadband signal generation during passive cavitation detection. Real-time CEU perfusion imaging with destruction-replenishment was then performed at 1.8 MHz in dogs using an MI of 0.1, 0.2, or 0.3. Sonazoid had a higher bulk modulus than Definity (66 ± 12 vs 29 ± 2 kPa, P = .02) and exhibited less inertial cavitation (destruction) at MIs ≥ 0.2. On in vivo CEU, maximal signal intensity increased incrementally with MI for both agents and was equivalent between agents except at an MI of 0.1 (60% and 85% lower for Sonazoid at 7 and 1.8 MHz, respectively, P power imaging coupled with a durable microbubble contrast agent. Copyright © 2015 American Society of Echocardiography. All rights reserved.

  16. Potential Hazards Relating to Pyrolysis of c-C4F8O, n-C4F10 and c-C4F8 in selected gaseous diffusion plant operations

    International Nuclear Information System (INIS)

    Trowbridge, L.D.

    2000-01-01

    As part of a program intended to replace the present evaporative coolant at the gaseous diffusion plants (GDPs) with a non-ozone-depleting alternate, a series of investigations of the suitability of candidate substitutes is under way. This report summarizes studies directed at estimating the chemical and thermal stability of three candidate coolants, c-C 4 F 8 O, n-C 4 F 10 and c-C 4 4F 8 , in a few specific environments to be found in gaseous diffusion plant operations

  17. Synthesis, biological evaluation, and baboon PET imaging of the potential adrenal imaging agent cholesteryl-p-[18f]fluorobenzoate

    International Nuclear Information System (INIS)

    Jonson, Stephanie D.; Welch, Michael J.

    1999-01-01

    Cholesteryl-p-[ 18 F]fluorobenzoate ([ 18 F]CFB) was investigated as a potential adrenal positron emission tomography (PET) imaging agent for the diagnostic imaging of adrenal disorders. We describe the synthesis, biodistribution, adrenal autoradiography, and baboon PET imaging of [ 18 F]CFB. The synthesis of [ 18 F]CFB was facilitated by the use of a specially designed microwave cavity that was instrumental in effecting 70-83% incorporation of fluorine-18 in 60 s via [ 18 F]fluoro-for-nitro exchange. Tissue distribution studies in mature female Sprague-Dawley rats showed good accumulation of [ 18 F]CFB in the steroid-secreting tissues, adrenals and ovaries, at 1 h postinjection. The effectiveness of [ 18 F]CFB to accumulate in diseased adrenals was shown through biodistribution studies in hypolipidemic rats, which showed a greater than threefold increase in adrenal uptake at 1 h and increased adrenal/liver and adrenal/kidney ratios. Analysis of the metabolites at 1 h in the blood, adrenals, spleen, and ovaries of hypolipidemic and control rats showed the intact tracer representing greater than 86%, 93%, 92%, and 82% of the accumulated activity, respectively. [ 18 F]CFB was confirmed to selectively accumulate in the adrenal cortex versus the adrenal medulla by autoradiography. Normal baboon PET imaging with [ 18 F]CFB effectively showed adrenal localization as early as 15 min after injection of the tracer, with enhanced adrenal contrast seen at 60-70 min. These results suggest that [ 18 F]CFB may be useful as an adrenal PET imaging agent for assessing adrenal disorders

  18. Progress of study on the dopamine D4 receptor imaging agent

    International Nuclear Information System (INIS)

    Tian Haibin; Zhang Lan; Zhang Chunfu; Li Junling; Yin Duanzhi

    2001-01-01

    Dopamine receptors were originally classified into five receptors subtypes, the dopamine D 4 receptor was included. Schizophrenic pathophysiology may be associated with expression and function of the dopamine D 4 receptor; it is of great importance to study the imaging agent of dopamine D 4 receptor. The study on radioactivity distribution and metabolize of radioligand remains hampered by the lack radioligand for the D 4 receptor which can be labeled using suitable nuclei. This paper reviews the progress of study on the dopamine D 4 receptor imaging agent, with particular emphasis vary nuclei, for example 11 C, 18 F, 123 I, labeled D 4 receptor ligands, antagonists and analogs as PET or SPECT imaging agents. Authors estimated affinity and selectivity of radioligands for the dopamine D 4 receptor in laboratory animal tests

  19. Acoustic Analysis of Nasal Vowels in Monguor Language

    Science.gov (United States)

    Zhang, Hanbin

    2017-09-01

    The purpose of the study is to analyze the spectrum characteristics and acoustic features for the nasal vowels [ɑ˜] and [ɔ˜] in Monguor language. On the base of acoustic parameter database of the Monguor speech, the study finds out that there are five main zero-pole pairs appearing for the nasal vowel [ɔ˜] and two zero-pole pairs appear for the nasal vowel [ɔ˜]. The results of regression analysis demonstrate that the duration of the nasal vowel [ɔ˜] or the nasal vowel [ɔ˜] can be predicted by its F1, F2 and F3 respectively.

  20. 18F-FDOPA PET/CT imaging of insulinoma revisited

    International Nuclear Information System (INIS)

    Imperiale, Alessio; Namer, Izzie-Jacques; Sebag, Frederic; Vix, Michel; Castinetti, Frederic; Kessler, Laurence; Moreau, Francois; Bachellier, Philippe; Guillet, Benjamin; Mundler, Olivier; Taieb, David

    2015-01-01

    18 F-FDOPA PET imaging is increasingly used in the work-up of patients with neuroendocrine tumours. It has been shown to be of limited value in localizing pancreatic insulin-secreting tumours in adults with hyperinsulinaemic hypoglycaemia (HH) mainly due to 18 F-FDOPA uptake by the whole pancreatic gland. The objective of this study was to review our experience with 18 F-FDOPA PET/CT imaging with carbidopa (CD) premedication in patients with HH in comparison with PET/CT studies performed without CD premedication in an independent population. A retrospective study including 16 HH patients who were investigated between January 2011 and December 2013 using 18 F-FDOPA PET/CT (17 examinations) in two academic endocrine tumour centres was conducted. All PET/CT examinations were performed under CD premedication (200 mg orally, 1 - 2 h prior to tracer injection). The PET/CT acquisition protocol included an early acquisition (5 min after 18 F-FDOPA injection) centred over the upper abdomen and a delayed whole-body acquisition starting 20 - 30 min later. An independent series of eight consecutive patients with HH and investigated before 2011 were considered for comparison. All patients had a reference whole-body PET/CT scan performed about 1 h after 18 F-FDOPA injection. In all cases, PET/CT was performed without CD premedication. In the study group, 18 F-FDOPA PET/CT with CD premedication was positive in 8 out of 11 patients with histologically proven insulinoma (73 %). All 18 F-FDOPA PET/CT-avid insulinomas were detected on early images and 5 of 11 (45 %) on delayed ones. The tumour/normal pancreas uptake ratio was not significantly different between early and delayed acquisitions. Considering all patients with HH, including those without imaging evidence of disease, the detection rate of the primary lesions using CD-assisted 18 F-FDOPA PET/CT was 53 %, showing 9 insulinomas in 17 studies performed. In the control group (without CD premedication, eight patients), the final

  1. The Role of 18F-FDG PET/CT Integrated Imaging in Distinguishing Malignant from Benign Pleural Effusion

    Science.gov (United States)

    Sun, Yajuan; Yu, Hongjuan; Ma, Jingquan

    2016-01-01

    Objective The aim of our study was to evaluate the role of 18F-FDG PET/CT integrated imaging in differentiating malignant from benign pleural effusion. Methods A total of 176 patients with pleural effusion who underwent 18F-FDG PET/CT examination to differentiate malignancy from benignancy were retrospectively researched. The images of CT imaging, 18F-FDG PET imaging and 18F-FDG PET/CT integrated imaging were visually analyzed. The suspected malignant effusion was characterized by the presence of nodular or irregular pleural thickening on CT imaging. Whereas on PET imaging, pleural 18F-FDG uptake higher than mediastinal activity was interpreted as malignant effusion. Images of 18F-FDG PET/CT integrated imaging were interpreted by combining the morphologic feature of pleura on CT imaging with the degree and form of pleural 18F-FDG uptake on PET imaging. Results One hundred and eight patients had malignant effusion, including 86 with pleural metastasis and 22 with pleural mesothelioma, whereas 68 patients had benign effusion. The sensitivities of CT imaging, 18F-FDG PET imaging and 18F-FDG PET/CT integrated imaging in detecting malignant effusion were 75.0%, 91.7% and 93.5%, respectively, which were 69.8%, 91.9% and 93.0% in distinguishing metastatic effusion. The sensitivity of 18F-FDG PET/CT integrated imaging in detecting malignant effusion was higher than that of CT imaging (p = 0.000). For metastatic effusion, 18F-FDG PET imaging had higher sensitivity (p = 0.000) and better diagnostic consistency with 18F-FDG PET/CT integrated imaging compared with CT imaging (Kappa = 0.917 and Kappa = 0.295, respectively). The specificities of CT imaging, 18F-FDG PET imaging and 18F-FDG PET/CT integrated imaging were 94.1%, 63.2% and 92.6% in detecting benign effusion. The specificities of CT imaging and 18F-FDG PET/CT integrated imaging were higher than that of 18F-FDG PET imaging (p = 0.000 and p = 0.000, respectively), and CT imaging had better diagnostic consistency with

  2. The Role of 18F-FDG PET/CT Integrated Imaging in Distinguishing Malignant from Benign Pleural Effusion.

    Science.gov (United States)

    Sun, Yajuan; Yu, Hongjuan; Ma, Jingquan; Lu, Peiou

    2016-01-01

    The aim of our study was to evaluate the role of 18F-FDG PET/CT integrated imaging in differentiating malignant from benign pleural effusion. A total of 176 patients with pleural effusion who underwent 18F-FDG PET/CT examination to differentiate malignancy from benignancy were retrospectively researched. The images of CT imaging, 18F-FDG PET imaging and 18F-FDG PET/CT integrated imaging were visually analyzed. The suspected malignant effusion was characterized by the presence of nodular or irregular pleural thickening on CT imaging. Whereas on PET imaging, pleural 18F-FDG uptake higher than mediastinal activity was interpreted as malignant effusion. Images of 18F-FDG PET/CT integrated imaging were interpreted by combining the morphologic feature of pleura on CT imaging with the degree and form of pleural 18F-FDG uptake on PET imaging. One hundred and eight patients had malignant effusion, including 86 with pleural metastasis and 22 with pleural mesothelioma, whereas 68 patients had benign effusion. The sensitivities of CT imaging, 18F-FDG PET imaging and 18F-FDG PET/CT integrated imaging in detecting malignant effusion were 75.0%, 91.7% and 93.5%, respectively, which were 69.8%, 91.9% and 93.0% in distinguishing metastatic effusion. The sensitivity of 18F-FDG PET/CT integrated imaging in detecting malignant effusion was higher than that of CT imaging (p = 0.000). For metastatic effusion, 18F-FDG PET imaging had higher sensitivity (p = 0.000) and better diagnostic consistency with 18F-FDG PET/CT integrated imaging compared with CT imaging (Kappa = 0.917 and Kappa = 0.295, respectively). The specificities of CT imaging, 18F-FDG PET imaging and 18F-FDG PET/CT integrated imaging were 94.1%, 63.2% and 92.6% in detecting benign effusion. The specificities of CT imaging and 18F-FDG PET/CT integrated imaging were higher than that of 18F-FDG PET imaging (p = 0.000 and p = 0.000, respectively), and CT imaging had better diagnostic consistency with 18F-FDG PET/CT integrated

  3. Methods And Systems For Using Reference Images In Acoustic Image Processing

    Science.gov (United States)

    Moore, Thomas L.; Barter, Robert Henry

    2005-01-04

    A method and system of examining tissue are provided in which a field, including at least a portion of the tissue and one or more registration fiducials, is insonified. Scattered acoustic information, including both transmitted and reflected waves, is received from the field. A representation of the field, including both the tissue and the registration fiducials, is then derived from the received acoustic radiation.

  4. A new assessment model for tumor heterogeneity analysis with [18]F-FDG PET images.

    Science.gov (United States)

    Wang, Ping; Xu, Wengui; Sun, Jian; Yang, Chengwen; Wang, Gang; Sa, Yu; Hu, Xin-Hua; Feng, Yuanming

    2016-01-01

    It has been shown that the intratumor heterogeneity can be characterized with quantitative analysis of the [18]F-FDG PET image data. The existing models employ multiple parameters for feature extraction which makes it difficult to implement in clinical settings for the quantitative characterization. This article reports an easy-to-use and differential SUV based model for quantitative assessment of the intratumor heterogeneity from 3D [18]F-FDG PET image data. An H index is defined to assess tumor heterogeneity by summing voxel-wise distribution of differential SUV from the [18]F-FDG PET image data. The summation is weighted by the distance of SUV difference among neighboring voxels from the center of the tumor and can thus yield increased values for tumors with peripheral sub-regions of high SUV that often serves as an indicator of augmented malignancy. Furthermore, the sign of H index is used to differentiate the rate of change for volume averaged SUV from its center to periphery. The new model with the H index has been compared with a widely-used model of gray level co-occurrence matrix (GLCM) for image texture characterization with phantoms of different configurations and the [18]F-FDG PET image data of 6 lung cancer patients to evaluate its effectiveness and feasibility for clinical uses. The comparison of the H index and GLCM parameters with the phantoms demonstrate that the H index can characterize the SUV heterogeneity in all of 6 2D phantoms while only 1 GLCM parameter can do for 1 and fail to differentiate for other 2D phantoms. For the 8 3D phantoms, the H index can clearly differentiate all of them while the 4 GLCM parameters provide complicated patterns in the characterization. Feasibility study with the PET image data from 6 lung cancer patients show that the H index provides an effective single-parameter metric to characterize tumor heterogeneity in terms of the local SUV variation, and it has higher correlation with tumor volume change after

  5. Spatial distribution of macroalgae along the shores of Kongsfjorden (West Spitsbergen using acoustic imaging

    Directory of Open Access Journals (Sweden)

    Kruss Aleksandra

    2017-06-01

    Full Text Available The identification of macroalgal beds is a crucial component for the description of fjord ecosystems. Direct, biological sampling is still the most popular investigation technique but acoustic methods are becoming increasingly recognized as a very efficient tool for the assessment of benthic communities. In 2007 we carried out the first acoustic survey of the littoral areas in Kongsfjorden. A 2.68 km2 area comprised within a 12.40 km2 euphotic zone was mapped along the fjord’s coast using single- and multi-beam echosounders. The singlebeam echosounder (SBES proved to be a very efficient and reliable tool for macroalgae detection in Arctic conditions. The multibeam echosounder (MBES was very useful in extending the SBES survey range, even though it’s ability in discriminating benthic communities was limited. The final result of our investigation is a map of the macroalgae distribution around the fjord, showing 39% macroalgae coverage (1.09 km2 of investigated area between isobaths -0.70 m and -30 m. Zonation analysis showed that most of the studied macroalgae areas occur up to 15 m depth (93%. These results were confirmed by biological sampling and observation in key areas. The potential of acoustic imaging of macrophytes, and a proposed methodology for the processing of acoustic data, are presented in this paper along with preliminary studies on the acoustic reflectivity of macroalgae, also highlighting differences among species. These results can be applied to future monitoring of the evolution of kelp beds in different areas of the Arctic, and in the rest of the world.

  6. Clostridium botulinum strains producing BoNT/F4 or BoNT/F5.

    Science.gov (United States)

    Raphael, Brian H; Bradshaw, Marite; Kalb, Suzanne R; Joseph, Lavin A; Lúquez, Carolina; Barr, John R; Johnson, Eric A; Maslanka, Susan E

    2014-05-01

    Botulinum neurotoxin type F (BoNT/F) may be produced by Clostridium botulinum alone or in combination with another toxin type such as BoNT/A or BoNT/B. Type F neurotoxin gene sequences have been further classified into seven toxin subtypes. Recently, the genome sequence of one strain of C. botulinum (Af84) was shown to contain three neurotoxin genes (bont/F4, bont/F5, and bont/A2). In this study, eight strains containing bont/F4 and seven strains containing bont/F5 were examined. Culture supernatants produced by these strains were incubated with BoNT/F-specific peptide substrates. Cleavage products of these peptides were subjected to mass spectral analysis, allowing detection of the BoNT/F subtypes present in the culture supernatants. PCR analysis demonstrated that a plasmid-specific marker (PL-6) was observed only among strains containing bont/F5. Among these strains, Southern hybridization revealed the presence of an approximately 242-kb plasmid harboring bont/F5. Genome sequencing of four of these strains revealed that the genomic backgrounds of strains harboring either bont/F4 or bont/F5 are diverse. None of the strains analyzed in this study were shown to produce BoNT/F4 and BoNT/F5 simultaneously, suggesting that strain Af84 is unusual. Finally, these data support a role for the mobility of a bont/F5-carrying plasmid among strains of diverse genomic backgrounds.

  7. Automated synthesis of the estrogen receptors imaging agent 18F-FES

    International Nuclear Information System (INIS)

    Guo Shen; Chen Guobao; Dai Hongfeng; Lin Meifu; Chen Wenxin

    2011-01-01

    Objective: 18 F-16α-17β-fluoroestradiol ( 18 F-FES), an estrogen receptors imaging agent, is synthesized with Tracerlab FX FN system. Methods: 18 F-FES is obtained by two steps reactions, including the nucleophilic displacement reaction of no-carrier-added 18 F-fluoride with 3-O-methoxymethyl-16, 17-O-sulfuryl-16-epiesteriol, then the intermediate is evaporated and hydrolyzed with HCI and finally gives 18 F-FES. Results: The synthesis of 18 F-FES can be completed in about 80 min.The radiochemical yield and radio-chemical purity are about 10% and 95% respectively. Conclusion: The procedure of synthesis is simple and automatical. 18 F-FES has an extremely low toxicity, which suggests that 18 F-FES may be a safe, a nd effective estrogen receptors imaging agent. (authors)

  8. The Use of Acoustic Radiation Force Decorrelation-Weighted Pulse Inversion for Enhanced Ultrasound Contrast Imaging.

    Science.gov (United States)

    Herbst, Elizabeth B; Unnikrishnan, Sunil; Wang, Shiying; Klibanov, Alexander L; Hossack, John A; Mauldin, Frank William

    2017-02-01

    The use of ultrasound imaging for cancer diagnosis and screening can be enhanced with the use of molecularly targeted microbubbles. Nonlinear imaging strategies such as pulse inversion (PI) and "contrast pulse sequences" (CPS) can be used to differentiate microbubble signal, but often fail to suppress highly echogenic tissue interfaces. This failure results in false-positive detection and potential misdiagnosis. In this study, a novel acoustic radiation force (ARF)-based approach was developed for superior microbubble signal detection. The feasibility of this technique, termed ARF decorrelation-weighted PI (ADW-PI), was demonstrated in vivo using a subcutaneous mouse tumor model. Tumors were implanted in the hindlimb of C57BL/6 mice by subcutaneous injection of MC38 cells. Lipid-shelled microbubbles were conjugated to anti-VEGFR2 antibody and administered via bolus injection. An image sequence using ARF pulses to generate microbubble motion was combined with PI imaging on a Verasonics Vantage programmable scanner. ADW-PI images were generated by combining PI images with interframe signal decorrelation data. For comparison, CPS images of the same mouse tumor were acquired using a Siemens Sequoia clinical scanner. Microbubble-bound regions in the tumor interior exhibited significantly higher signal decorrelation than static tissue (n = 9, P < 0.001). The application of ARF significantly increased microbubble signal decorrelation (n = 9, P < 0.01). Using these decorrelation measurements, ADW-PI imaging demonstrated significantly improved microbubble contrast-to-tissue ratio when compared with corresponding CPS or PI images (n = 9, P < 0.001). Contrast-to-tissue ratio improved with ADW-PI by approximately 3 dB compared with PI images and 2 dB compared with CPS images. Acoustic radiation force can be used to generate adherent microbubble signal decorrelation without microbubble bursting. When combined with PI, measurements of the resulting microbubble signal

  9. F-18 FDG PET/CT imaging of primary hepatic neuroendocrine tumor

    Directory of Open Access Journals (Sweden)

    Katsuya Mitamura

    2015-01-01

    Full Text Available Primary hepatic neuroendocrine tumors (PHNETs are extremely rare neoplasms. Herein, we report a case of a 70-year-old man with a hepatic mass. The non-contrast computed tomography (CT image showed a low-density mass, and dynamic CT images indicated the enhancement of the mass in the arterial phase and early washout in the late phase. F18- fluorodeoxyglucose (18F-FDG positron emission tomography (PET and fused PET/CT images showed increased uptake in the hepatic mass. Whole-body 18F-FDG PET images showed no abnormal activity except for the liver lesion. Presence of an extrahepatic tumor was also ruled out by performing upper gastrointestinal endoscopy, total colonoscopy, and chest and abdominal CT. A posterior segmentectomy was performed, and histologic examination confirmed a neuroendocrine tumor (grade 1. The patient was followed up for about 2 years after the resection, and no extrahepatic lesions were radiologically found. Therefore, the patient was diagnosed with PHNET. To the best of our knowledge, no previous case of PHNET have been detected by 18F-FDG PET imaging.

  10. PET imaging of α{sub 7} nicotinic acetylcholine receptors: a comparative study of [{sup 18}F]ASEM and [{sup 18}F]DBT-10 in nonhuman primates, and further evaluation of [{sup 18}F]ASEM in humans

    Energy Technology Data Exchange (ETDEWEB)

    Hillmer, Ansel T.; Li, Songye; Zheng, Ming-Qiang; Lin, Shu-fei; Nabulsi, Nabeel; Holden, Daniel; Pracitto, Richard; Labaree, David; Ropchan, Jim; Esterlis, Irina; Cosgrove, Kelly P.; Carson, Richard E.; Huang, Yiyun [Yale University, PET Center, New Haven, CT (United States); Scheunemann, Matthias; Teodoro, Rodrigo; Deuther-Conrad, Winnie; Brust, Peter [Helmholtz-Zentrum Dresden-Rossendorf, Institute of Radiopharmaceutical Cancer Research, Leipzig (Germany)

    2017-06-15

    The α{sub 7} nicotinic acetylcholine receptor (nAChR) is implicated in many neuropsychiatric disorders, making it an important target for positron emission tomography (PET) imaging. The first aim of this work was to compare two α{sub 7} nAChRs PET radioligands, [{sup 18}F]ASEM 3-(1,4-diazabicyclo[3.2.2]nonan-4-yl)-6-([{sup 18}F]fluorodibenzo[b,d]thiophene 5,5-dioxide) and [{sup 18}F]DBT-10 7-(1,4-diazabicyclo[3.2.2]nonan-4-yl)-2-([{sup 18}F]fluorodibenzo[b,d]thiophene 5,5-dioxide), in nonhuman primates. The second aim was to assess further the quantification and test-retest variability of [{sup 18}F]ASEM in humans. PET scans with high specific activity [{sup 18}F]ASEM or [{sup 18}F]DBT-10 were acquired in three rhesus monkeys (one male, two female), and the kinetic properties of these radiotracers were compared. Additional [{sup 18}F]ASEM PET scans with blocking doses of nicotine, varenicline, and cold ASEM were acquired separately in two animals. Next, six human subjects (five male, one female) were imaged with [{sup 18}F]ASEM PET for 180 min, and arterial sampling was used to measure the parent input function. Different modeling approaches were compared to identify the optimal analysis method and scan duration for quantification of [{sup 18}F]ASEM distribution volume (V{sub T}). In addition, retest scans were acquired in four subjects (three male, one female), and the test-retest variability of V{sub T} was assessed. In the rhesus monkey brain [{sup 18}F]ASEM and [{sup 18}F]DBT-10 exhibited highly similar kinetic profiles. Dose-dependent blockade of [{sup 18}F]ASEM binding was observed, while administration of either nicotine or varenicline did not change [{sup 18}F]ASEM V{sub T}. [{sup 18}F]ASEM was selected for further validation because it has been used in humans. Accurate quantification of [{sup 18}F]ASEM V{sub T} in humans was achieved using multilinear analysis with at least 90 min of data acquisition, resulting in V{sub T} values ranging from 19.6 ± 2

  11. Evidence from acoustic imaging for submarine volcanic activity in 2012 off the west coast of El Hierro (Canary Islands, Spain)

    Science.gov (United States)

    Pérez, Nemesio M.; Somoza, Luis; Hernández, Pedro A.; de Vallejo, Luis González; León, Ricardo; Sagiya, Takeshi; Biain, Ander; González, Francisco J.; Medialdea, Teresa; Barrancos, José; Ibáñez, Jesús; Sumino, Hirochika; Nogami, Kenji; Romero, Carmen

    2014-12-01

    We report precursory geophysical, geodetic, and geochemical signatures of a new submarine volcanic activity observed off the western coast of El Hierro, Canary Islands. Submarine manifestation of this activity has been revealed through acoustic imaging of submarine plumes detected on the 20-kHz chirp parasound subbottom profiler (TOPAS PS18) mounted aboard the Spanish RV Hespérides on June 28, 2012. Five distinct "filament-shaped" acoustic plumes emanating from the flanks of mounds have been recognized at water depth between 64 and 88 m on a submarine platform located NW El Hierro. These plumes were well imaged on TOPAS profiles as "flares" of high acoustic contrast of impedance within the water column. Moreover, visible plumes composed of white rafts floating on the sea surface and sourcing from the location of the submarine plumes were reported by aerial photographs on July 3, 2012, 5 days after acoustic plumes were recorded. In addition, several geophysical and geochemical data support the fact that these submarine vents were preceded by several precursory signatures: (i) a sharp increase of the seismic energy release and the number of daily earthquakes of magnitude ≥2.5 on June 25, 2012, (ii) significant vertical and horizontal displacements observed at the Canary Islands GPS network (Nagoya University-ITER-GRAFCAN) with uplifts up to 3 cm from June 25 to 26, 2012, (iii) an anomalous increase of the soil gas radon activity, from the end of April until the beginning of June reaching peak values of 2.7 kBq/m3 on June 3, 2012, and (iv) observed positive peak in the air-corrected value of 3He/4He ratio monitored in ground waters (8.5 atmospheric 3He/4He ratio ( R A)) at the northwestern El Hierro on June 16, 2012. Combining these submarine and subaerial information, we suggest these plumes are the consequence of submarine vents exhaling volcanic gas mixed with fine ash as consequence of an event of rapid rise of volatile-rich magma beneath the NW submarine ridge

  12. Spectroscopic study of the interaction of Nd{sup +3} with amino acids: phenomenological 4f-4f intensity parameters

    Energy Technology Data Exchange (ETDEWEB)

    Jerico, Soraya; Carubelli, Celia R.; Massabni, Ana M.G.; Stucchi, Elizabeth B.; Leite, Sergio R. de A. [UNESP, Araraquara, SP (Brazil). Inst. de Quimica; Malta, Oscar [Pernambuco Univ., Recife, PE (Brazil). Dept. de Quimica Fundamental

    1998-10-01

    We have studied behaviour of the phenomenological 4f-4f intensity parameters in compounds of the Nd{sup 3+} ion with glycine, L-aspartic acid, L-glutamic acid, L-histidine, DL-malic acid and Aspartame{sup TM} in aqueous solution, as function of the pK values and partial charges on the oxygens of the carboxylate groups of these molecules. The results are discussed and qualitatively interpreted in terms of the forced electric dipole and dynamic coupling mechanisms of the 4f-4f intensities, thus indicating that the forced electric dipole mechanism is dominant. (author)

  13. Synthesis and preliminary evaluation of 9-(4-[{sup 18}F]fluoro-3-hydroxymethylbutyl) guanine ([{sup 18}F]FHBG) in HSV1-tk gene transduced hepatoma cell

    Energy Technology Data Exchange (ETDEWEB)

    Moon, Byung Seok; Lee, Tae Sup [Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of); Lee, Myoung Keun [Yonsei University, Wonju (Korea, Republic of)] (and others)

    2006-08-15

    The HSV1-tk reporter gene system is the most widely used system because of its advantage that direct monitoring is possible without the introduction of a separate reporter gene in case of HSV1-tk suicide gene therapy. In this study, we investigate the usefulness of the reporter probe (substrate), 9-(4-[{sup 18}F]fluoro-3-hydroxymethylbutyl) guanine ([{sup 18}F]FHBG) for non-invasive reporter gene imaging using PET in HSV1-tk expressing hepatoma model. Radiolabeled FHBG was prepared in 8 steps from a commercially available triester. The labeling reaction was carried out by NCA nucleophilic substitution with K[{sup 18}F]/K2.2.2. in acetonitrile using N2-monomethoxytrityl-9-[4-(tosly)-3-monomethoxytritylmethylbutl] guanine as a precursor, followed by deprotection with 1 N HCI. Preliminary biological properties of the probe were evaluated with MCA cells and MCA-tk cells transduced with HSV1-tk reporter gene. In vitro uptake and release-out studies of [{sup 18}F]FHBG were performed, and was analyzed correlation between [{sup 18}F]FHBG uptake ratio according to increasing numeric count of MCA-tk cells and degree of gene expression. MicroPET scan image was obtained with MCA and MCA-tk tumor beating Balb/c-nude mouse model. [{sup 18}F]FHBG was purified by reverse phase semi-HPLC system and collected at around 16-18 min. Radiochemical yield was about 20-25% (corrected for decay), radiochemical purity was > 95% and specific activity was around > 55.5 GBq/ {mu} mol. Specific accumulation of [{sup 18}F]FHBG was observed in HSV1-tk gene transduced MCA-tk cells but not MCA cells, and consecutive 1 hour release-out results showed more than 86% of uptaked [{sup 18}F]FHBG was retained inside of cells. The uptake of [{sup 18}F]FHBG was showed a highly significant linear correlation (R{sup 2} = 0.995) with increasing percentage of MCA-tk numeric cell count. In microPET scan images, remarkable difference of accumulation was observed for the two type of tumors. [{sup 18}F]FHBG appears

  14. Effect of subcutaneous injection of insulin on 18F-FDG myocardial imaging in diabetics

    International Nuclear Information System (INIS)

    Tian Yueqin; Shi Rongfang; Guo Feng; Wei Hongxing; Wu Qingwen; Liu Xiujie

    2001-01-01

    Objective: To evaluate the effect of subcutaneous injection of insulin on 18 F-fluorodeoxyglucose (FDG) myocardial imaging in patients with diabetes mellitus. Methods: Fifty-seven patients with coronary artery disease complicated with diabetes mellitus [mean age (60 +- 8) years] underwent 18 F-FDG PET and dual isotope simultaneous acquisition SPECT with 99 Tc m -MIBI/ 18 F-FDG. Thirty minutes before FDG injection, blood glucose was measured with an automatic glucose analyzer and insulin was subcutaneously used, the dose was adjusted according to the level of blood glucose. Results: Regression analysis showed that the insulin was positively associated with blood glucose. The linear regression analysis showed that the correlation between dose of insulin (y) and blood glucose (x) was good, r 0.8172; the linear regression equation was y = -5.4 + 1.2x. 52 of 57 images were of good quality with 91% success rate. Conclusion: Subcutaneous injection of insulin is an effective and simple method for obtaining cardiac FDG images of good quality in patients with diabetes mellitus

  15. Modifying the size and uniformity of upconversion Yb/Er:NaGdF4 nanocrystals through alkaline-earth doping.

    Science.gov (United States)

    Lei, Lei; Chen, Daqin; Huang, Ping; Xu, Ju; Zhang, Rui; Wang, Yuansheng

    2013-11-21

    NaGdF4 is regarded as an ideal upconversion (UC) host material for lanthanide (Ln(3+)) activators because of its unique crystal structure, high Ln(3+) solubility, low phonon energy and high photochemical stability, and Ln(3+)-doped NaGdF4 UC nanocrystals (NCs) have been widely investigated as bio-imaging and magnetic resonance imaging agents recently. To realize their practical applications, controlling the size and uniformity of the monodisperse Ln(3+)-doped NaGdF4 UC NCs is highly desired. Unlike the routine routes by finely adjusting the multiple experimental parameters, herein we provide a facile and straightforward strategy to modify the size and uniformity of NaGdF4 NCs via alkaline-earth doping for the first time. With the increase of alkaline-earth doping content, the size of NaGdF4 NCs increases gradually, while the size-uniformity is still retained. We attribute this "focusing" of size distribution to the diffusion controlled growth of NaGdF4 NCs induced by alkaline-earth doping. Importantly, adopting the Ca(2+)-doped Yb/Er:NaGdF4 NCs as cores, the complete Ca/Yb/Er:NaGdF4@NaYF4 core-shell particles with excellent size-uniformity can be easily achieved. However, when taking the Yb/Er:NaGdF4 NCs without Ca(2+) doping as cores, they could not be perfectly covered by NaYF4 shells, and the obtained products are non-uniform in size. As a result, the UC emission intensity of the complete core-shell NCs increases by about 30 times in comparison with that of the cores, owing to the effective surface passivation of the Ca(2+)-doped cores and therefore protection of Er(3+) in the cores from the non-radiative decay caused by surface defects, whereas the UC intensity of the incomplete core-shell NCs is enhanced by only 3 times.

  16. Shallow Water Acoustics Studies

    Science.gov (United States)

    2017-11-19

    LE O CEAN RAPHIC I TITUTI Appli d Oc:ean Physics and E11gi1i,ering Depar1111,11t vember 9, 2017 Dr. Robert Headrick ffice of Naval Resear h, ode...UNIT NUMBER 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) 8. PERFORMING ORGANIZATION REPORT Applied Ocean Physics and Engineering Department...2015). [3] J.F. Lynch and A.E. Newhall, "Shallow water acoustics", book chapter in "Practical Underwater Acoustics," L. Bjorno, T. Neighbors, and D

  17. Brauer algebra of type F4

    NARCIS (Netherlands)

    Liu, S.

    2012-01-01

    We present an algebra related to the Coxeter group of type F4 which can be viewed as the Brauer algebra of type F4 and is obtained as a subalgebra of the Brauer algebra of type E6. We also describe some properties of this algebra.

  18. Brauer algebras of type F4

    NARCIS (Netherlands)

    Liu, S.

    2013-01-01

    We present an algebra related to the Coxeter group of type F4 which can be viewed as the Brauer algebra of type F4 and is obtained as a subalgebra of the Brauer algebra of type E6. We also describe some properties of this algebra.

  19. Ion-molecular equilibria and activity determination in the RbF-ZrF4 system

    International Nuclear Information System (INIS)

    Skokan, E.V.; Nikitin, M.I.; Sorokin, I.D.; Korenev, Yu.M.; Sidorov, L.N.

    1983-01-01

    Activity of zirconium tetrofluoride in 100-33.3 mol % ZrF 4 concentration range was determined during isothermal evaporation of samples of different initial composition of RbF-ZrF 4 system, using ion-molecular equilibrium method. It became possible, using the exchange ion-molecular reactions to determine ZrF 4 activity approximately 10 -10 in the region of state diagram of RbF-ZrF 4 system, adjoining to rubidium fluoride. The comparative analysis of results, obtained by the methods of isothermal evaporation, ion-molecular equilibria is given; the advantages and restrictions of ion-molecular equilibrium method are presented

  20. Synchronized imaging and acoustic analysis of the upper airway in patients with sleep-disordered breathing

    International Nuclear Information System (INIS)

    Chang, Yi-Chung; Pham, Van-Truong; Wang, Yung-Hung; Lin, Chen; Lo, Men-Tzung; Huon, Leh-Kiong; Wang, Pa-Chun; Chen, Yunn-Jy; Jiang, Sun-Fen; Shih, Tiffany Ting-Fang; Tran, Thi-Thao; Tsao, Jenho

    2014-01-01

    Progressive narrowing of the upper airway increases airflow resistance and can produce snoring sounds and apnea/hypopnea events associated with sleep-disordered breathing due to airway collapse. Recent studies have shown that acoustic properties during snoring can be altered with anatomic changes at the site of obstruction. To evaluate the instantaneous association between acoustic features of snoring and the anatomic sites of obstruction, a novel method was developed and applied in nine patients to extract the snoring sounds during sleep while performing dynamic magnetic resonance imaging (MRI). The degree of airway narrowing during the snoring events was then quantified by the collapse index (ratio of airway diameter preceding and during the events) and correlated with the synchronized acoustic features. A total of 201 snoring events (102 pure retropalatal and 99 combined retropalatal and retroglossal events) were recorded, and the collapse index as well as the soft tissue vibration time were significantly different between pure retropalatal (collapse index, 24  ±  11%; vibration time, 0.2  ±  0.3 s) and combined (retropalatal and retroglossal) snores (collapse index, 13  ±  7% [P ≤ 0.0001]; vibration time, 1.2  ±  0.7 s [P ≤ 0.0001]). The synchronized dynamic MRI and acoustic recordings successfully characterized the sites of obstruction and established the dynamic relationship between the anatomic site of obstruction and snoring acoustics. (paper)

  1. PERFORMA NEUTRONIK BAHAN BAKAR LiF-BeF2-ThF4-UF4 PADA SMALL MOBILE-MOLTEN SALT REACTOR

    Directory of Open Access Journals (Sweden)

    S. N. Rokhman

    2015-04-01

    Full Text Available Telah dilakukan analisis terhadap performa neutronik bahan bakar garam lebur LiF-BeF2-ThF4-UF4 pada Small Mobile-Molten Salt Reactor (SM-MSR. Penyesuaian konfigurasi teras dan temperatur operasi harus dilakukan untuk penggunaan bahan bakar baru tersebut agar mencapai keff > 1 dan CR (conversion ratio > 1 pada fraksi 0,5% 233U, 20% 232Th, 28% Li, 51,5% Be. Setelah didapat nilai keff ≈ 1 dan CR ≈ 1, dilakukan analisis pengaruh perubahan Th terhadap Be dan Be terhadap Li yang terlihat dalam perubahan parameter keff dan CR. Setelah itu fraksi 233U divariasi antara 0,5–0,46% untuk memperoleh keff > 1 dan CR > 1. Dalam perhitungan koefisien reaktifitas temperatur (αT, temperatur teras dinaikkan sebesar +25K dan +50K., dan untuk koefisien reaktifitas void (αV, densitas bahan bakar dikurangi hingga 90%. Hasil perhitungan menunjukkan bahwa pengurangan Th terhadap Be menyebabkan penurunan nilai CR dan naiknya keff akibat berkurangnya material fertil. Sebaliknya penambahan Be terhadap Li mengakibatkan terjadi kenaikan nilai keff dan menurunkan CR, akibat laju serapan Li lebih besar dari Be. Pada 5 (lima fraksi 233U dalam rentang 0,5–0,49%, hasil perhitungan keff dan CR masing-masing bervariasi dalam rentang 1,00001 - 1,00327 dan 1,00016 - 1,00731. Untuk faktor puncak daya (PPF, hasil perhitungan memberikan nilai dalam rentang 2,4311 -2,4714. Sedangkan untuk parameter keselamatan, koefisien reaktivitas temperatur (αT dan reaktivitas void (αV masingmasing bernilai negatif dalam rentang 4,972×10-5 - 5,909×10-5 dan 2,596×10-2- 2,8287×10-2 ∆k/k/K. Dapat disimpulkan bahwa teras SM-MSR memberikan nilai negatif di kedua koefisien reaktivitas tersebut untuk setiap fraksi,, sehingga memenuhi kriteria keselamatan dan keselamatan melekat. Kata kunci: SM-MSR (small mobile-molten salt reactor, bahan bakar LiF-BeF2-ThF4-UF4, keselamatan melekat, koefisien reaktivitas temperatur, koefisien reaktivitas void   The analysis of neutronic performance has

  2. Radiosynthesis and pre-clinical evaluation of [{sup 18}F]fluoro-[1,2-{sup 2}H{sub 4}]choline

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Graham [Comprehensive Cancer Imaging Centre, Faculty of Medicine, Imperial College London, Hammersmith Hospital, Du Cane Road, London W12 0NN (United Kingdom); Zhao Yongjun [MDx Discovery (part of GE Healthcare) at Hammersmith Imanet, Ltd., Hammersmith Hospital, Du Cane Road, London W12 0NN (United Kingdom); Leyton, Julius [Comprehensive Cancer Imaging Centre, Faculty of Medicine, Imperial College London, Hammersmith Hospital, Du Cane Road, London W12 0NN (United Kingdom); Shan Bo [MDx Discovery (part of GE Healthcare) at Hammersmith Imanet, Ltd., Hammersmith Hospital, Du Cane Road, London W12 0NN (United Kingdom); Nguyen, Quang-de; Perumal, Meg [Comprehensive Cancer Imaging Centre, Faculty of Medicine, Imperial College London, Hammersmith Hospital, Du Cane Road, London W12 0NN (United Kingdom); Turton, David [GE-Imanet, Hammersmith Hospital, Du Cane Road, London, W12 0NN (United Kingdom); Arstad, Erik; Luthra, Sajinder K.; Robins, Edward G. [MDx Discovery (part of GE Healthcare) at Hammersmith Imanet, Ltd., Hammersmith Hospital, Du Cane Road, London W12 0NN (United Kingdom); Aboagye, Eric O., E-mail: eric.aboagye@imperial.ac.u [Comprehensive Cancer Imaging Centre, Faculty of Medicine, Imperial College London, Hammersmith Hospital, Du Cane Road, London W12 0NN (United Kingdom)

    2011-01-15

    Introduction: Choline radiotracers are widely used for clinical PET diagnosis in oncology. [{sup 11}C]Choline finds particular utility in the imaging of brain and prostate tumor metabolic status, where 2-[{sup 18}F]fluoro-2-deoxy-D-glucose ('FDG') shows high background uptake. More recently we have extended the clinical utility of [{sup 11}C]choline to breast cancer where radiotracer uptake correlates with tumor aggressiveness (grade). In the present study, a new choline analog, [{sup 18}F]fluoro-[1,2-{sup 2}H{sub 4}]choline, was synthesized and evaluated as a potential PET imaging probe. Methods: [{sup 18}F]Fluorocholine, [{sup 18}F]fluoro-[1-{sup 2}H{sub 2}]choline and [{sup 18}F]fluoro-[1,2-{sup 2}H{sub 4}]choline were synthesized by alkylation of the relevant precursor with [{sup 18}F]fluorobromomethane or [{sup 18}F]fluoromethyl tosylate. Radiosynthesis of [{sup 18}F]fluoromethyl tosylate required extensive modification of the existing method. [{sup 18}F]Fluorocholine and [{sup 18}F]fluoro-[1,2-{sup 2}H{sub 4}]choline were then subjected to in vitro oxidative stability analysis in a chemical oxidation model using potassium permanganate and an enzymatic model using choline oxidase. The two radiotracers, together with the corresponding di-deuterated compound, [{sup 18}F]fluoro-[1-{sup 2}H{sub 2}]choline, were then evaluated in vivo in a time-course biodistribution study in HCT-116 tumor-bearing mice. Results: Alkylation with [{sup 18}F]fluoromethyl tosylate proved to be the most reliable radiosynthetic route. Stability models indicate that [{sup 18}F]fluoro-[1,2-{sup 2}H{sub 4}]choline possesses increased chemical and enzymatic (choline oxidase) oxidative stability relative to [{sup 18}F]fluorocholine. The distribution of the three radiotracers, [{sup 18}F]fluorocholine, [{sup 18}F]fluoro-[1-{sup 2}H{sub 2}]choline and [{sup 18}F]fluoro-[1,2-{sup 2}H{sub 4}]choline, showed a similar uptake profile in most organs. Crucially, tumor uptake of [{sup 18}F

  3. Development and validation of a combined phased acoustical radiosity and image source model for predicting sound fields in rooms.

    Science.gov (United States)

    Marbjerg, Gerd; Brunskog, Jonas; Jeong, Cheol-Ho; Nilsson, Erling

    2015-09-01

    A model, combining acoustical radiosity and the image source method, including phase shifts on reflection, has been developed. The model is denoted Phased Acoustical Radiosity and Image Source Method (PARISM), and it has been developed in order to be able to model both specular and diffuse reflections with complex-valued and angle-dependent boundary conditions. This paper mainly describes the combination of the two models and the implementation of the angle-dependent boundary conditions. It furthermore describes how a pressure impulse response is obtained from the energy-based acoustical radiosity by regarding the model as being stochastic. Three methods of implementation are proposed and investigated, and finally, recommendations are made for their use. Validation of the image source method is done by comparison with finite element simulations of a rectangular room with a porous absorber ceiling. Results from the full model are compared with results from other simulation tools and with measurements. The comparisons of the full model are done for real-valued and angle-independent surface properties. The proposed model agrees well with both the measured results and the alternative theories, and furthermore shows a more realistic spatial variation than energy-based methods due to the fact that interference is considered.

  4. Low carbohydrate diet before 18F-FDG tumor imaging contributes to reduce myocardial 18F-FDG uptake

    International Nuclear Information System (INIS)

    Miao Weibing; Chen Shaoming; Zheng Shan; Wu Jing; Peng Jiequan; Jiang Zhihong

    2014-01-01

    Objective: To evaluate whether low carbohydrate diet before 18 F-FDG tumor imaging could reduce myocardial 18 F-FDG uptake. Methods: From April 2011 to January 2012, 70 patients were enrolled in this study.They were randomly divided into control group (34 cases) and test group (36 cases). Patients in control group were on regular diet, while those in test group had low carbohydrate diet in the evening before imaging. Blood samples were taken before injection of 18 F-FDG for the measurement of serum glucose, free fatty acid,insulin and ketone body. Whole body 18 F-FDG tomography was performed with dual-head coincidence SPECT. The myocardial uptake of FDG was assessed visually and scored as 0 for no uptake, 1 for uptake lower than liver, 2 for uptake similar to liver, 3 for uptake higher than liver, and 4 for remarkable uptake.The ratio of myocardium to liver (H/L) was calculated. Two-sample t test, Wilcoxon rank sum test and linear correlation analysis were performed. Results: The myocardial uptake in test group was significantly lower than that in control group with H/L ratios of 0.94±0.57 and 1.50±1.04, respectively (t=-2.75, P<0.05). The concentrations of serum free fatty acid and ketone body in test group were significantly higher than those in control group: (0.671±0.229) mmol/L vs (0.547±0.207) mmol/L and (0.88±0.60) mmol/L vs (0.57±0.32) mmol/L, t=2.38 and 2.67, both P<0.05. The concentrations of glucose and insulin were (5.28±1.06) mmol/L and (35.16±33.70) pmol/L in test group, which showed no significant difference with those in control group ((5.19±0.78) mmol/L and (41.64±35.13) pmol/L, t=0.39 and-0.79, both P>0.05). A negative correlation was found between the myocardial uptake of 18 F-FDG and serum free fatty acid/ketone body concentration (r=-0.40, -0.33, both P<0.01), respectively. There was no correlation between the myocardial uptake of 18 F-FDG and glucose/insulin (r=-0.02, 0.13, both P>0.05), respectively. Conclusion: Low carbohydrate

  5. Analysis list: E2f4 [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available E2f4 Blood,Embryonic fibroblast,Liver,Muscle,Pluripotent stem cell + mm9 http://dba...rchive.biosciencedbc.jp/kyushu-u/mm9/target/E2f4.1.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/target/E2f4....5.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/target/E2f4.10.tsv http://dbarchive.biosciencedbc....jp/kyushu-u/mm9/colo/E2f4.Blood.tsv,http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/colo/E2f4....Embryonic_fibroblast.tsv,http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/colo/E2f4.Liver.tsv,htt

  6. Atmospheric histories and growth trends of C4F10, C5F12, C6F14, C7F16 and C8F18

    Directory of Open Access Journals (Sweden)

    R. F. Weiss

    2012-05-01

    Full Text Available Atmospheric observations and trends are presented for the high molecular weight perfluorocarbons (PFCs: decafluorobutane (C4F10, dodecafluoropentane (C5F12, tetradecafluorohexane (C6F14, hexadecafluoroheptane (C7F16 and octadecafluorooctane (C8F18. Their atmospheric histories are based on measurements of 36 Northern Hemisphere and 46 Southern Hemisphere archived air samples collected between 1973 to 2011 using the Advanced Global Atmospheric Gases Experiment (AGAGE "Medusa" preconcentration gas chromatography-mass spectrometry systems. A new calibration scale was prepared for each PFC, with estimated accuracies of 6.8% for C4F10, 7.8% for C5F12, 4.0% for C6F14, 6.6% for C7F16 and 7.9% for C8F18. Based on our observations the 2011 globally averaged dry air mole fractions of these heavy PFCs are: 0.17 parts-per-trillion (ppt, i.e., parts per 1012 for C4F10, 0.12 ppt for C5F12, 0.27 ppt for C6F14, 0.12 ppt for C7F16 and 0.09 ppt for C8F18. These atmospheric mole fractions combine to contribute to a global average radiative forcing of 0.35 mW m−2, which is 6% of the total anthropogenic PFC radiative forcing (Montzka and Reimann, 2011; Oram et al., 2012. The growth rates of the heavy perfluorocarbons were largest in the late 1990s peaking at 6.2 parts per quadrillion (ppq, i.e., parts per 1015 per year (yr for C4F10, at 5.0 ppq yr−1 for C5F12 and 16.6 ppq yr−1 for C6F14 and in the early 1990s for C7F16 at 4.7 ppq yr−1 and in the mid 1990s for C8F18 at 4.8 ppq yr−1. The 2011 globally averaged mean atmospheric growth rates of these PFCs are subsequently lower at 2.2 ppq yr−1 for C4F10, 1.4 ppq yr−1 for C5F12, 5.0 ppq yr−1 for C6F14, 3.4 ppq yr−1 for C7F16 and 0.9 ppq yr−1 for C8F18. The more recent slowdown in the growth rates suggests that emissions are declining as compared to the 1980s and 1990s.

  7. 18F-NaF PET/CT: EANM procedure guidelines for bone imaging

    International Nuclear Information System (INIS)

    Beheshti, M.; Langsteger, W.; Mottaghy, F.M.; Payche, F.; Behrendt, F.F.F.; Wyngaert, T.V. den; Fogelman, I.; Strobel, K.; Celli, M.; Fanti, S.; Giammarile, F.; Krause, B.

    2015-01-01

    The aim of this guideline is to provide minimum standards for the performance and interpretation of 18 F-NaF PET/CT scans. Standard acquisition and interpretation of nuclear imaging modalities will help to provide consistent data acquisition and numeric values between different platforms and institutes and to promote the use of PET/CT modality as an established diagnostic modality in routine clinical practice. This will also improve the value of scientific work and its contribution to evidence-based medicine. (orig.)

  8. Acoustic effects of single electrostatic discharges

    International Nuclear Information System (INIS)

    Orzech, Łukasz

    2015-01-01

    Electric discharges, depending on their character, can emit different types of energy, resulting in different effects. Single electrostatic discharges besides generation of electromagnetic pulses are also the source of N acoustic waves. Their specified parameters depending on amount of discharging charge enable determination of value of released charge in a function of acoustic descriptor (e.g. acoustic pressure). Presented approach is the basics of acoustic method for measurement of single electrostatic discharges, enabling direct and contactless measurement of value of charge released during ESD. Method for measurement of acoustic effect of impact of a single electrostatic discharge on the environment in a form of pressure shock wave and examples of acoustic descriptors in a form of equation Q=f(p a ) are described. The properties of measuring system as well as the results of regression static analyses used to determine the described relationships are analysed in details. (paper)

  9. Using oral 18F-FDG for infection imaging

    International Nuclear Information System (INIS)

    Bolwell, Jacob J.

    2009-01-01

    Full text:A 22-year-old female with a complex medical history presented to our department with a complaint of pain around the site her Portocath (PaC). Multiple imaging techniques failed to identify any sign of infection around the pac. A 99 m Tc-Phytate Colloid labelled white cell (LWC) scan was arranged to identify any infective processes in or around the pac. Severe difficulty was encountered attempting to gain IV access aside from the pac and the LWC scan had to aborted. In order to identify infection of the pac a Positron Emission Tomography (PET) scan using oral administration 18F-fluorodeoxyglucose (18F-FDG) was arranged. The oral 18F-FDG PET scan showed active glucose metabolism around the site of the pac port and along the cathe tubing near the medial right clavicle. As a result of this the pac was removed and replaced and the patient is now receiving continued antibiotics and medication through her new POC. In conclusion we found oral administration of 18F-FDG to be a suitable alternative to IV administered 18F-FDG in on to obtain functional imaging in a case where there was severe difficulty in obtaining venous access.

  10. Acoustic field modulation in regenerators

    Science.gov (United States)

    Hu, J. Y.; Wang, W.; Luo, E. C.; Chen, Y. Y.

    2016-12-01

    The regenerator is a key component that transfers energy between heat and work. The conversion efficiency is significantly influenced by the acoustic field in the regenerator. Much effort has been spent to quantitatively determine this influence, but few comprehensive experimental verifications have been performed because of difficulties in modulating and measuring the acoustic field. In this paper, a method requiring two compressors is introduced and theoretically investigated that achieves acoustic field modulation in the regenerator. One compressor outputs the acoustic power for the regenerator; the other acts as a phase shifter. A RC load dissipates the acoustic power out of both the regenerator and the latter compressor. The acoustic field can be modulated by adjusting the current in the two compressors and opening the RC load. The acoustic field is measured with pressure sensors instead of flow-field imaging equipment, thereby greatly simplifying the experiment.

  11. Positron emission tomography imaging of cardiomyocyte apoptosis with a novel molecule probe [18F]FP-DPAZn2

    Science.gov (United States)

    Sun, Ting; Tang, Ganghua; Tian, Hua; Hu, Kongzhen; Yao, Shaobo; Su, Yifan; Wang, Changqian

    2015-01-01

    Cardiomyocyte apoptosis plays a causal role in the development and progression of heart failure. Currently, there is no effective imaging agent that can be used to detect cardiomyocyte apoptosis in vivo. To target phosphatidylserine (PS) on the surface of the dying cell, we synthesized a novel 18F-labeled Zn2+-dipicolylamine (DPA) analog, [18F]FP-DPAZn2, and evaluated it for noninvasive imaging of cardiomyocyte apoptosis. In vitro, the fluorescence imaging of dansyl-DPAZn2 was suitable for detecting cardiomyocyte apoptosis, which was confirmed by confocal immunofluorescence imaging, terminal dUTP nick-end labeling (TUNEL) assay, and western blot assay. The in vivo biodistribution showed that the uptake ratios of [18F]FP-DPAZn2 in the heart were 4.41±0.29% ID/g at 5 min, 2.40 ± 0.43% ID/g at 30 min, 1.63 ± 0.26% ID/g at 60 min, and 1.43% ± 0.07 ID/g at 120 min post-injection. In vivo, the [18F]FP-DPAZn2 PET images showed more cardiac accumulation of radioactivity 60 min post-injection in acute myocardial infarction (AMI) rats than in normal rats, which was consistent with the findings of a histological analysis of the rat cardiac tissues in vitro. [18F]FP-DPAZn2 PET imaging has the capability for myocardial apoptosis detection, but the method will require improved myocardial uptake for the noninvasive evaluation of cardiomyocyte apoptosis in clinical settings. PMID:26416423

  12. Acoustic characteristics of modern Greek Orthodox Church music.

    Science.gov (United States)

    Delviniotis, Dimitrios S

    2013-09-01

    Some acoustic characteristics of the two types of vocal music of the Greek Orthodox Church Music, the Byzantine chant (BC) and ecclesiastical speech (ES), are studied in relation to the common Greek speech and the Western opera. Vocal samples were obtained, and their acoustic parameters of sound pressure level (SPL), fundamental frequency (F0), and the long-time average spectrum (LTAS) characteristics were analyzed. Twenty chanters, including two chanters-singers of opera, sang (BC) and read (ES) the same hymn of Byzantine music (BM), the two opera singers sang the same aria of opera, and common speech samples were obtained, and all audio were analyzed. The distribution of SPL values showed that the BC and ES have higher SPL by 9 and 12 dB, respectively, than common speech. The average F0 in ES tends to be lower than the common speech, and the smallest standard deviation (SD) of F0 values characterizes its monotonicity. The tone-scale intervals of BC are close enough to the currently accepted theory with SD equal to 0.24 semitones. The rate and extent of vibrato, which is rare in BC, equals 4.1 Hz and 0.6 semitones, respectively. The average LTAS slope is greatest in BC (+4.5 dB) but smaller than in opera (+5.7 dB). In both BC and ES, instead of a singer's formant appearing in an opera voice, a speaker's formant (SPF) was observed around 3300 Hz, with relative levels of +6.3 and +4.6 dB, respectively. The two vocal types of BM, BC, and ES differ both to each other and common Greek speech and opera style regarding SPL, the mean and SD of F0, the LTAS slope, and the relative level of SPF. Copyright © 2013 The Voice Foundation. Published by Mosby, Inc. All rights reserved.

  13. Whole-body radiation dosimetry of 2-[18F]Fluoro-A-85380 in human PET imaging studies

    International Nuclear Information System (INIS)

    Obrzut, Sebastian L.; Koren, Andrei O.; Mandelkern, Mark A.; Brody, Arthur L.; Hoh, Carl K.; London, Edythe D.

    2005-01-01

    2-[ 18 F]Fluoro-A-85380 (2-[ 18 F]fluoro-3-(2(S)-azetidinylmethoxy)pyridine, 2-[ 18 F]FA) is a recently developed PET radioligand for noninvasive imaging of nicotinic acetylcholine receptors. Previous radiation absorbed dose estimates for 2-[ 18 F]FA were limited to evaluation of activity in only several critical organs. Here, we performed 2-[ 18 F]FA radiation dosimetry studies on two healthy human volunteers to obtain data for all important body organs. Intravenous injection of 2.9 MBq/kg of 2-[ 18 F]FA was followed by dynamic PET imaging. Regions of interest were placed over images of each organ to generate time-activity curves, from which we computed residence times. Radiation absorbed doses were calculated from the residence times using the MIRDOSE 3.0 program (version 3.0, ORISE, Oak Ridge, TN). The urinary bladder wall receives the highest radiation absorbed dose (0.153 mGy/MBq, 0.566 rad/mCi, for a 2.4-h voiding interval), followed by the liver (0.0496 mGy/MBq, 0.184 rad/mCi) and the kidneys (0.0470 mGy/MBq, 0.174 rad/mCi). The mean effective dose equivalent is estimated to be 0.0278 mSv/MBq (0.103 rem/mCi), indicating that radiation dosimetry associated with 2-[ 18 F]FA is within acceptable limits

  14. Synthesis, biological evaluation, and baboon PET imaging of the potential adrenal imaging agent cholesteryl-p-[{sup 18}f]fluorobenzoate

    Energy Technology Data Exchange (ETDEWEB)

    Jonson, Stephanie D.; Welch, Michael J. E-mail: welch@mirlink.wustl.edu

    1999-01-01

    Cholesteryl-p-[{sup 18}F]fluorobenzoate ([{sup 18}F]CFB) was investigated as a potential adrenal positron emission tomography (PET) imaging agent for the diagnostic imaging of adrenal disorders. We describe the synthesis, biodistribution, adrenal autoradiography, and baboon PET imaging of [{sup 18}F]CFB. The synthesis of [{sup 18}F]CFB was facilitated by the use of a specially designed microwave cavity that was instrumental in effecting 70-83% incorporation of fluorine-18 in 60 s via [{sup 18}F]fluoro-for-nitro exchange. Tissue distribution studies in mature female Sprague-Dawley rats showed good accumulation of [{sup 18}F]CFB in the steroid-secreting tissues, adrenals and ovaries, at 1 h postinjection. The effectiveness of [{sup 18}F]CFB to accumulate in diseased adrenals was shown through biodistribution studies in hypolipidemic rats, which showed a greater than threefold increase in adrenal uptake at 1 h and increased adrenal/liver and adrenal/kidney ratios. Analysis of the metabolites at 1 h in the blood, adrenals, spleen, and ovaries of hypolipidemic and control rats showed the intact tracer representing greater than 86%, 93%, 92%, and 82% of the accumulated activity, respectively. [{sup 18}F]CFB was confirmed to selectively accumulate in the adrenal cortex versus the adrenal medulla by autoradiography. Normal baboon PET imaging with [{sup 18}F]CFB effectively showed adrenal localization as early as 15 min after injection of the tracer, with enhanced adrenal contrast seen at 60-70 min. These results suggest that [{sup 18}F]CFB may be useful as an adrenal PET imaging agent for assessing adrenal disorders.

  15. Automated synthesis of ["1"8F](2S,4R)-4-fluoroglutamine on a GE TRACERlab™ FX-N Pro module

    International Nuclear Information System (INIS)

    Zhang, Xiang; Basuli, Falguni; Shi, Zhen-Dan; Xu, Biying; Blackman, Burchelle; Choyke, Peter L.; Swenson, Rolf E.

    2016-01-01

    Glutamine (Gln) and its analogues may serve as imaging agents for tumor diagnosis using positron emission tomography (PET), especially for tumors with negative ["1"8F]FDG scan. We report the first automated synthesis of ["1"8F](2S,4R)-4-fluoroglutamine (["1"8F]FGln) on a GE TRACERlab™ FX-N Pro module. ["1"8F]FGln was obtained in 80±3 min with a radiochemical yield of 21±3% (n=5, uncorrected). The radiochemical purity was >98%, and optical purity 90±5%. The synthesis is highly reproducible with good chemical purity, radiochemical yield, and is suitable for translation to cGMP production. - Highlights: • The radiosynthesis of ["1"8F]fluoroglutamine was optimized with improved yield and purity. • Fully automated synthesis was established on a GE TRACERlab™ FX-N Pro module. • Radiochemical yield of 21±3% (uncorrected, n=5) was obtained with good reproducibility. • The automation could be easily adapted to cGMP production for routine clinical use.

  16. GMP-compliant automated synthesis of [{sup 18}F]AV-45 (Florbetapir F 18) for imaging {beta}-amyloid plaques in human brain

    Energy Technology Data Exchange (ETDEWEB)

    Yao, C.-H. [Department of Nuclear Medicine and Molecular Imaging Center, Chang Gung Memorial Hospital, Taiwan (China); Lin, K.-J. [Department of Nuclear Medicine and Molecular Imaging Center, Chang Gung Memorial Hospital, Taiwan (China); Department of Medical Imaging and Radiological Sciences, Chang Gung University, 259 Wen-Hua 1st Road, Kweishan, Taoyuan 333, Taiwan (China); Weng, C.-C. [Department of Medical Imaging and Radiological Sciences, Chang Gung University, 259 Wen-Hua 1st Road, Kweishan, Taoyuan 333, Taiwan (China); Hsiao, I.-T. [Department of Nuclear Medicine and Molecular Imaging Center, Chang Gung Memorial Hospital, Taiwan (China); Department of Medical Imaging and Radiological Sciences, Chang Gung University, 259 Wen-Hua 1st Road, Kweishan, Taoyuan 333, Taiwan (China); Ting, Y.-S. [Department of Nuclear Medicine and Molecular Imaging Center, Chang Gung Memorial Hospital, Taiwan (China); Yen, T.-C. [Department of Nuclear Medicine and Molecular Imaging Center, Chang Gung Memorial Hospital, Taiwan (China); Department of Medical Imaging and Radiological Sciences, Chang Gung University, 259 Wen-Hua 1st Road, Kweishan, Taoyuan 333, Taiwan (China); Jan, T.-R. [Department and Graduate Institute of Veterinary Medicine, National Taiwan University, Taipei, Taiwan (China); Skovronsky, Daniel [Avid Radiopharmaceuticals, Inc., Philadelphia, PA 19104 (United States); Kung, M.-P. [Department of Nuclear Medicine and Molecular Imaging Center, Chang Gung Memorial Hospital, Taiwan (China); Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104 (United States); Wey, S.-P., E-mail: spwey@mail.cgu.edu.t [Department of Nuclear Medicine and Molecular Imaging Center, Chang Gung Memorial Hospital, Taiwan (China); Department of Medical Imaging and Radiological Sciences, Chang Gung University, 259 Wen-Hua 1st Road, Kweishan, Taoyuan 333, Taiwan (China)

    2010-12-15

    We report herein the Good Manufacturing Practice (GMP)-compliant automated synthesis of {sup 18}F-labeled styrylpyridine, AV-45 (Florbetapir), a novel tracer for positron emission tomography (PET) imaging of {beta}-amyloid (A{beta}) plaques in the brain of Alzheimer's disease patients. [{sup 18}F]AV-45 was prepared in 105 min using a tosylate precursor with Sumitomo modules for radiosynthesis under GMP-compliant conditions. The overall yield was 25.4{+-}7.7% with a final radiochemical purity of 95.3{+-}2.2% (n=19). The specific activity of [{sup 18}F]AV-45 reached as high as 470{+-}135 TBq/mmol (n=19). The present studies show that [{sup 18}F]AV-45 can be manufactured under GMP-compliant conditions and could be widely available for routine clinical use.

  17. Semi-automated preparation of the dopamine transporter ligand [18F]FECNT for human PET imaging studies

    International Nuclear Information System (INIS)

    Voll, Ronald J.; McConathy, Jonathan; Waldrep, Michael S.; Crowe, Ronald J.; Goodman, Mark M.

    2005-01-01

    The fluorine-18 labeled dopamine transport (DAT) ligand 2β-carbomethoxy-3β-(4-chlorophenyl)-8-(2-fluoroethyl)nortropane (FECNT) has shown promising properties as an in vivo DAT imaging agent in human and monkey PET studies. A semi-automated synthesis has been developed to reliably produce [ 18 F]FECNT in a 16% decay corrected yield. This method utilizes a new [ 18 F]fluoralkylating agent and provides high purity [ 18 F]FECNT in a formulation suitable for human use

  18. Impact of motion compensation and partial volume correction for 18F-NaF PET/CT imaging of coronary plaque

    Science.gov (United States)

    Cal-González, J.; Tsoumpas, C.; Lassen, M. L.; Rasul, S.; Koller, L.; Hacker, M.; Schäfers, K.; Beyer, T.

    2018-01-01

    Recent studies have suggested that 18F-NaF-PET enables visualization and quantification of plaque micro-calcification in the coronary tree. However, PET imaging of plaque calcification in the coronary arteries is challenging because of the respiratory and cardiac motion as well as partial volume effects. The objective of this work is to implement an image reconstruction framework, which incorporates compensation for respiratory as well as cardiac motion (MoCo) and partial volume correction (PVC), for cardiac 18F-NaF PET imaging in PET/CT. We evaluated the effect of MoCo and PVC on the quantification of vulnerable plaques in the coronary arteries. Realistic simulations (Biograph TPTV, Biograph mCT) and phantom acquisitions (Biograph mCT) were used for these evaluations. Different uptake values in the calcified plaques were evaluated in the simulations, while three ‘plaque-type’ lesions of 36, 31 and 18 mm3 were included in the phantom experiments. After validation, the MoCo and PVC methods were applied in four pilot NaF-PET patient studies. In all cases, the MoCo-based image reconstruction was performed using the STIR software. The PVC was obtained from a local projection (LP) method, previously evaluated in preclinical and clinical PET. The results obtained show a significant increase of the measured lesion-to-background ratios (LBR) in the MoCo  +  PVC images. These ratios were further enhanced when using directly the tissue-activities from the LP method, making this approach more suitable for the quantitative evaluation of coronary plaques. When using the LP method on the MoCo images, LBR increased between 200% and 1119% in the simulated data, between 212% and 614% in the phantom experiments and between 46% and 373% in the plaques with positive uptake observed in the pilot patients. In conclusion, we have built and validated a STIR framework incorporating MoCo and PVC for 18F-NaF PET imaging of coronary plaques. First results indicate an improved

  19. Analyzing the Acoustic Beat with Mobile Devices

    Science.gov (United States)

    Kuhn, Jochen; Vogt, Patrik; Hirth, Michael

    2014-01-01

    In this column, we have previously presented various examples of how physical relationships can be examined by analyzing acoustic signals using smartphones or tablet PCs. In this example, we will be exploring the acoustic phenomenon of small beats, which is produced by the overlapping of two tones with a low difference in frequency ?f. The…

  20. Radiosynthesis and initial evaluation of [18F]-FEPPA for PET imaging of peripheral benzodiazepine receptors

    International Nuclear Information System (INIS)

    Wilson, Alan A.; Garcia, Armando; Parkes, Jun; McCormick, Patrick; Stephenson, Karin A.; Houle, Sylvain; Vasdev, Neil

    2008-01-01

    Introduction: A novel [ 18 F]-radiolabelled phenoxyanilide, [ 18 F]-FEPPA, has been synthesized and evaluated, in vitro and ex vivo, as a potential positron emission tomography imaging agent for the peripheral benzodiazepine receptor (PBR). Methods: [ 18 F]-FEPPA and two other radiotracers for imaging PBR, namely [ 11 C]-PBR28 and [ 11 C]-PBR28-d3, were synthesised and evaluated in vitro and ex vivo as potential PBR imaging agents. Results: [ 18 F]-FEPPA is efficiently prepared in one step from its tosylate precursor and [ 18 F]-fluoride in high radiochemical yields and at high specific activity. FEPPA displayed a K i of 0.07 nM for PBR in rat mitochondrial membrane preparations and a suitable lipophilicity for brain penetration (log P of 2.99 at pH 7.4). Upon intravenous injection into rats, [ 18 F]-FEPPA showed moderate brain uptake [standard uptake value (SUV) of 0.6 at 5 min] and a slow washout (SUV of 0.35 after 60 min). Highest uptake of radioactivity was seen in the hypothalamus and olfactory bulb, regions previously reported to be enriched in PBR in rat brain. Analysis of plasma and brain extracts demonstrated that [ 18 F]-FEPPA was rapidly metabolized, but no lipophilic metabolites were observed in either preparation and only 5% radioactive metabolites were present in brain tissue extracts. Blocking studies to determine the extent of specific binding of [ 18 F]-FEPPA in rat brain were problematic due to large perturbations in circulating radiotracer and the lack of a reference region. Conclusions: Further evaluation of the potential of [ 18 F]-FEPPA will require the employment of rigorous kinetic models and/or appropriate animal models

  1. Differential diagnosis of idiopathic granulomatous mastitis and breast cancer using acoustic radiation force impulse imaging.

    Science.gov (United States)

    Teke, Memik; Teke, Fatma; Alan, Bircan; Türkoğlu, Ahmet; Hamidi, Cihad; Göya, Cemil; Hattapoğlu, Salih; Gumus, Metehan

    2017-01-01

    Differentiation of idiopathic granulomatous mastitis (IGM) from carcinoma with routine imaging methods, such as ultrasonography (US) and mammography, is difficult. Therefore, we evaluated the value of a newly developed noninvasive technique called acoustic radiation force impulse imaging in differentiating IGM versus malignant lesions in the breast. Four hundred and eighty-six patients, who were referred to us with a presumptive diagnosis of a mass, underwent Virtual Touch tissue imaging (VTI; Siemens) and Virtual Touch tissue quantification (VTQ; Siemens) after conventional gray-scale US. US-guided percutaneous needle biopsy was then performed on 276 lesions with clinically and radiologically suspicious features. Malignant lesions (n = 122) and IGM (n = 48) were included in the final study group. There was a statistically significant difference in shear wave velocity marginal and internal values between the IGM and malignant lesions. The median marginal velocity for IGM and malignant lesions was 3.19 m/s (minimum-maximum 2.49-5.82) and 5.05 m/s (minimum-maximum 2.09-8.46), respectively (p < 0.001). The median internal velocity for IGM and malignant lesions was 2.76 m/s (minimum-maximum 1.14-4.12) and 4.79 m/s (minimum-maximum 2.12-8.02), respectively (p < 0.001). The combination of VTI and VTQ as a complement to conventional US provides viscoelastic properties of tissues, and thus has the potential to increase the specificity of US.

  2. TU-F-12A-05: Sensitivity of Textural Features to 3D Vs. 4D FDG-PET/CT Imaging in NSCLC Patients

    Energy Technology Data Exchange (ETDEWEB)

    Yang, F; Nyflot, M; Bowen, S; Kinahan, P; Sandison, G [University of Washington Medical Center, Seattle, WA (United States)

    2014-06-15

    Purpose: Neighborhood Gray-level difference matrices (NGLDM) based texture parameters extracted from conventional (3D) 18F-FDG PET scans in patients with NSCLC have been previously shown to associate with response to chemoradiation and poorer patient outcome. However, the change in these parameters when utilizing respiratory-correlated (4D) FDG-PET scans has not yet been characterized for NSCLC. The Objectives: of this study was to assess the extent to which NGLDM-based texture parameters on 4D PET images vary with reference to values derived from 3D scans in NSCLC. Methods: Eight patients with newly diagnosed NSCLC treated with concomitant chemoradiotherapy were included in this study. 4D PET scans were reconstructed with OSEM-IR in 5 respiratory phase-binned images and corresponding CT data of each phase were employed for attenuation correction. NGLDM-based texture features, consisting of coarseness, contrast, busyness, complexity and strength, were evaluated for gross tumor volumes defined on 3D/4D PET scans by radiation oncologists. Variation of the obtained texture parameters over the respiratory cycle were examined with respect to values extracted from 3D scans. Results: Differences between texture parameters derived from 4D scans at different respiratory phases and those extracted from 3D scans ranged from −30% to 13% for coarseness, −12% to 40% for contrast, −5% to 50% for busyness, −7% to 38% for complexity, and −43% to 20% for strength. Furthermore, no evident correlations were observed between respiratory phase and 4D scan texture parameters. Conclusion: Results of the current study showed that NGLDM-based texture parameters varied considerably based on choice of 3D PET and 4D PET reconstruction of NSCLC patient images, indicating that standardized image acquisition and analysis protocols need to be established for clinical studies, especially multicenter clinical trials, intending to validate prognostic values of texture features for NSCLC.

  3. 18F-FDG PET/CT imaging of 100 normal adrenal gland cases

    International Nuclear Information System (INIS)

    Yu Zhiguo; Qu Wanying; Yao Zhiming; Zheng Jianguo; Song Renhe; Liu Xiuqin

    2008-01-01

    Objective: The purpose of this study was to obtain the 18 F-fluorodeoxyglucose (FDG) uptake characteristics in normal adrenal gland as the criteria to diagnose abnormal glucose metabolism in ad- renal gland by 18 F-FDG PET or PET/CT imaging. Methods: One hundred healthy persons underwent 18 F- FDG PET/CT imaging in this study. The images were reviewed by visual judgement and measured by stand-ardized uptake value (SUV). With reference to normal liver, the uptake of adrenal gland was scored from 0 to 3, namely, 0=no uptake, 1=less than the uptake of normal liver, 2=equal to the uptake of normal liver, 3=more than the uptake of normal liver. SUV was measured on the trans-axial images. The regions of interest (ROIs) of adrenal glands and livers were manually drawn based on the CT images. Both average SUV (SUV avg ) and maximum SUV(SUV max ) were calculated. Results: (1) By visual judgment, 94% and 91% of left and right normal adrenal glands had uptake intensity less than that of livers. (2) The SUV avg of left and right adrenal glands were 1.39 and 1.65, and the SUV max 1.98 and 2.19, respectively with the up- per limit of 95% confidence interval (Cf). (3)The ratios of left and right adrenal glands SUV avg to livers SUV avg were 0.65 and 0.75 and left and right adrenal glands SUV max to livers SUV max were 0.76 and 0.83 respectively with the upper limit of 95% CI. (4)The uptake of right adrenal gland was higher than that of the left. (5)There was no significant difference of the SUVs between men and women, except that right ad- renal gland SUV max of men was higher than that of women. (6) There was no significant difference in 18 F- FDG uptake between persons younger and elder than 60 years old. Conclusion: The physiological FDG uptake of the adrenal gland in normal healthy individuals is generally lower than that of liver. (authors)

  4. CLEC4F is an inducible C-type lectin in F4/80-positive cells and is involved in alpha-galactosylceramide presentation in liver.

    Directory of Open Access Journals (Sweden)

    Chih-Ya Yang

    Full Text Available CLEC4F, a member of C-type lectin, was first purified from rat liver extract with high binding affinity to fucose, galactose (Gal, N-acetylgalactosamine (GalNAc, and un-sialylated glucosphingolipids with GalNAc or Gal terminus. However, the biological functions of CLEC4F have not been elucidated. To address this question, we examined the expression and distribution of murine CLEC4F, determined its binding specificity by glycan array, and investigated its function using CLEC4F knockout (Clec4f-/- mice. We found that CLEC4F is a heavily glycosylated membrane protein co-expressed with F4/80 on Kupffer cells. In contrast to F4/80, CLEC4F is detectable in fetal livers at embryonic day 11.5 (E11.5 but not in yolk sac, suggesting the expression of CLEC4F is induced as cells migrate from yolk cells to the liver. Even though CLEC4F is not detectable in tissues outside liver, both residential Kupffer cells and infiltrating mononuclear cells surrounding liver abscesses are CLEC4F-positive upon Listeria monocytogenes (L. monocytogenes infection. While CLEC4F has strong binding to Gal and GalNAc, terminal fucosylation inhibits CLEC4F recognition to several glycans such as Fucosyl GM1, Globo H, Bb3∼4 and other fucosyl-glycans. Moreover, CLEC4F interacts with alpha-galactosylceramide (α-GalCer in a calcium-dependent manner and participates in the presentation of α-GalCer to natural killer T (NKT cells. This suggests that CLEC4F is a C-type lectin with diverse binding specificity expressed on residential Kupffer cells and infiltrating monocytes in the liver, and may play an important role to modulate glycolipids presentation on Kupffer cells.

  5. Oxygen Consumption and Acoustic Activity of Adult Callosobruchus maculatus (F.) (Coleoptera: Chrysomelidae: Bruchinae) during Hermetic Storage.

    Science.gov (United States)

    Njoroge, Anastasia W; Mankin, Richard W; Smith, Bradley W; Baributsa, Dieudonne

    2018-04-20

    Acoustic monitoring was applied to consider hermetic exposure durations and oxygen levels required to stop adult Callosobruchus maculatus activity and economic damage on cowpea. A 15-d study was conducted with six treatments of 25, 50, and 100 C. maculatus adults in 500 and 1000 mL jars using acoustic probes inserted through stoppers sealing the jars. Acoustic activity as a result of locomotion, mating, and egg-laying was measured by identifying sound impulses with frequency spectra representative of known insect sounds, and counting trains (bursts) of impulses separated by intervals of <200 ms, that typically are produced only by insects. By the end of the first week of storage in all treatments, oxygen levels declined to levels below 4%, which has been demonstrated to cause mortality in previous studies. Concomitantly, insect sound burst rates dropped below an acoustic detection threshold of 0.02 bursts s −1 , indicating that the insects had ceased feeding. Statistically significant relationships were obtained between two different measures of the acoustic activity and the residual oxygen level. Based on the experimental results, a simple equation can be used to estimate the time needed for oxygen to decline to levels that limit insect feeding damage and thus grain losses in hermetic storage containers of different insect population levels and various volumes.

  6. ToF-SIMS measurements with topographic information in combined images.

    Science.gov (United States)

    Koch, Sabrina; Ziegler, Georg; Hutter, Herbert

    2013-09-01

    In 2D and 3D time-of-flight secondary ion mass spectrometric (ToF-SIMS) analysis, accentuated structures on the sample surface induce distorted element distributions in the measurement. The origin of this effect is the 45° incidence angle of the analysis beam, recording planar images with distortion of the sample surface. For the generation of correct element distributions, these artifacts associated with the sample surface need to be eliminated by measuring the sample surface topography and applying suitable algorithms. For this purpose, the next generation of ToF-SIMS instruments will feature a scanning probe microscope directly implemented in the sample chamber which allows the performance of topography measurements in situ. This work presents the combination of 2D and 3D ToF-SIMS analysis with topographic measurements by ex situ techniques such as atomic force microscopy (AFM), confocal microscopy (CM), and digital holographic microscopy (DHM). The concept of the combination of topographic and ToF-SIMS measurements in a single representation was applied to organic and inorganic samples featuring surface structures in the nanometer and micrometer ranges. The correct representation of planar and distorted ToF-SIMS images was achieved by the combination of topographic data with images of 2D as well as 3D ToF-SIMS measurements, using either AFM, CM, or DHM for the recording of topographic data.

  7. Non-Imaging Acoustical Properties in Monitoring Arteriovenous Hemodialysis Access. A Review

    Directory of Open Access Journals (Sweden)

    Anas Mohd Noor

    2015-12-01

    Full Text Available The limitations of the gold standard angiography technique in arteriovenous access surveillance have opened a gap for researchers to find the best way to monitor this condition with low-cost, non-invasive and continuous bedside monitoring. The phonoangiography technique has been developed prior to these limits. This measurement and monitoring technique, associated with intelligence signal processing, promises better analysis for early detection of hemodialysis access problems, such as stenosis and thrombosis. Some research groups have shown that the phonoangiography technique could identify as many as 20% of vascular diameter changes and also its frequency characteristics due to hemodialysis access problems. The frequency characteristics of these acoustical signals are presented and discussed in detail to understand the association with the stenosis level, blood flows, sensor locations, fundamental frequency bands of normal and abnormal conditions, and also the spectral energy produced. This promising technique could be used in the near future as a tool for pre-diagnosis of arteriovenous access before any further access correction by surgical techniques is required. This paper provides an extensive review of various arteriovenous access monitoring techniques based on non-imaging acoustical properties.

  8. Radiosynthesis of dimethyl-2-[{sup 18}F]-(fluoromethyl)-6-methyl-4-(2-nitrophenyl)-1,4-dihydropyridine-3,5-dicarboxylate for L-type calcium channel imaging

    Energy Technology Data Exchange (ETDEWEB)

    Sadeghpour, H. [Nuclear Medicine Research Group, Agricultural, Medical and Industrial Research School (AMIRS), Karaj (Iran); Faculty of Pharmacy and Pharmaceutical Sciences Research Center, Tehran Univ. of Medical Sciences, Tehran (Iran); Jalilian, A.R.; Akhlaghi, M.; Mirzaei, M. [Nuclear Medicine Research Group, Agricultural, Medical and Industrial Research School (AMIRS), Karaj (Iran); Shafiee, A. [Faculty of Pharmacy and Pharmaceutical Sciences Research Center, Tehran Univ. of Medical Sciences, Tehran (Iran); Miri, R. [Medicinal and Natural Products Chemistry Research Center, Shiraz Univ. of Medical Sciences, Shiraz (Iran)

    2008-07-01

    Dimethyl 2-(fluoromethyl)-6-methyl-4-(2-nitrophenyl)-1,4-dihydropyridine-3,5-dicarboxylate 4a, a fluorinated nifedipine analog, has been shown to elicit significant calcium channel blocker activity using a guinea pig ileal longitudinal smooth muscle model. In order to perform biological studies for detection of L-type calcium channel distribution, we decided to prepare the [{sup 18}F]-labeled compound. The latter compound was prepared in no-carrier-added (n.c.a.) form from dimethyl 2-(bromomethyl)-6-methyl-4-(2-nitrophenyl)-1,4-dihydropyridine-3,5-dicarboxylate 2 in one step at 80 C in Kryptofix[222]/K[{sup 18}F]F and acetonitrile as a solvent in 15 min. Column chromatography afforded the radiochemically pure compound in 20 min. Radiochemical purity of the {sup 18}F-nifedipine was determined by RTLC and HPLC (> 98%) and specific activity of 21-48 GBq/{mu}mol (EOB). (orig.)

  9. Synthesis and evaluation of ortho-[18F]fluorocelecoxib for COX-2 cholangiocarcinoma imaging

    Directory of Open Access Journals (Sweden)

    Chang CW

    2018-05-01

    Full Text Available Chi-Wei Chang,1,* Chun-Nan Yeh,2,* Yi-Hsiu Chung,3,* Yong-Ren Chen,4 Shi-Wei Tien,4 Tsung-Wen Chen,2 Shiou-Shiow Farn,4,5 Ying-Cheng Huang,6 Chung-Shan Yu4,7 1Department of Nuclear Medicine, Taipei Veterans General Hospital, Taipei, Taiwan; 2Department of Surgery, Liver Research Center, Chang-Gung Memorial Hospital at Linkou, Chang Gung University, Taoyuan, Taiwan; 3Center for Advanced Molecular Imaging and Translation, Chang Gung Memorial Hospital, Taoyuan, Taiwan; 4Department of Biomedical Engineering and Environmental Sciences, National Tsinghua University, Hsinchu, Taiwan; 5Isotope Application Division, Institute of Nuclear Energy Research, Taoyuan, Taiwan; 6Department of Neurosurgery, Chang-Gung Memorial Hospital at Linkou, Chang Gung University, Taoyuan, Taiwan; 7Institute of Nuclear Engineering and Science, National Tsinghua University, Hsinchu, Taiwan *These authors contributed equally to this work Background: An 18F-tagged NSAID analog was prepared for use as a probe for COX-2 expression, which is associated with tumor development. Methods: The in vivo uptake of celecoxib was monitored with ortho-[18F]fluorocelecoxib using positron emission tomography (PET. The binding affinity of ortho-[18F]fluorocelecoxib to COX-1 and COX-2 enzymes were assessed using the competitor celecoxib. Results: The IC50 values were 0.039 μM and 0.024 μM, respectively. A selectivity index of 1.63 was obtained (COX-2 vs COX-1. COX-2 overexpressed cholangiocarcinoma (CCA murine cells took up more ortho-[18F]fluorocelecoxib than that by usual CCA cells from 10 to 60 minutes post incubation. Competitive inhibition (blocking of the tracer uptake of ortho-[18F]fluorocelecoxib in the presence of celecoxib by the COX-2 overexpressed CCA cells and the usual CCA cells gave the IC50 values of 0.5 μM and 46.5 μM, respectively. Based on the in vitro accumulation data and in vivo metabolism half-life (30 min, PET scanning was performed 30–60 min after the

  10. Thermodynamic assessment of the LiF–NaF–BeF{sub 2}–ThF{sub 4}–UF{sub 4} system

    Energy Technology Data Exchange (ETDEWEB)

    Capelli, E.; Beneš, O., E-mail: ondrej.benes@ec.europa.eu; Konings, R.J.M.

    2014-06-01

    The present study describes the full thermodynamic assessment of the LiF–NaF–BeF{sub 2}–ThF{sub 4}–UF{sub 4} system which is one of the key systems considered for a molten salt reactor fuel. The work is an extension of the previously assessed LiF–NaF–ThF{sub 4}–UF{sub 4} system with addition of BeF{sub 2} which is characterized by very low neutron capture cross section and a relatively low melting point. To extend the database the binary BeF{sub 2}–ThF{sub 4} and BeF{sub 2}–UF{sub 4} systems were optimized and the novel data were used for the thermodynamic assessment of BeF{sub 2} containing ternary systems for which experimental data exist in the literature. The obtained database is used to optimize the molten salt reactor fuel composition and to assess its properties with the emphasis on the melting behaviour.

  11. Disruption of Mouse Cytochrome P450 4f14 (Cyp4f14 Gene) Causes Severe Perturbations in Vitamin E Metabolism*

    Science.gov (United States)

    Bardowell, Sabrina A.; Duan, Faping; Manor, Danny; Swanson, Joy E.; Parker, Robert S.

    2012-01-01

    Vitamin E is a family of naturally occurring and structurally related lipophilic antioxidants, one of which, α-tocopherol (α-TOH), selectively accumulates in vertebrate tissues. The ω-hydroxylase cytochrome P450–4F2 (CYP4F2) is the only human enzyme shown to metabolize vitamin E. Using cDNA cloning, cell culture expression, and activity assays, we identified Cyp4f14 as a functional murine ortholog of CYP4F2. We then investigated the effect of Cyp4f14 deletion on vitamin E metabolism and status in vivo. Cyp4f14-null mice exhibited substrate-specific reductions in liver microsomal vitamin E-ω-hydroxylase activity ranging from 93% (γ-TOH) to 48% (γ-tocotrienol). In vivo data obtained from metabolic cage studies showed whole-body reductions in metabolism of γ-TOH of 90% and of 68% for δ- and α-TOH. This metabolic deficit in Cyp4f14−/− mice was partially offset by increased fecal excretion of nonmetabolized tocopherols and of novel ω-1- and ω-2-hydroxytocopherols. 12′-OH-γ-TOH represented 41% of whole-body production of γ-TOH metabolites in Cyp4f14−/− mice fed a soybean oil diet. Despite these counterbalancing mechanisms, Cyp4f14-null mice fed this diet for 6 weeks hyper-accumulated γ-TOH (2-fold increase over wild-type littermates) in all tissues and appeared normal. We conclude that CYP4F14 is the major but not the only vitamin E-ω-hydroxylase in mice. Its disruption significantly impairs whole-body vitamin E metabolism and alters the widely conserved phenotype of preferential tissue deposition of α-TOH. This model animal and its derivatives will be valuable in determining the biological actions of specific tocopherols and tocotrienols in vivo. PMID:22665481

  12. F-19 MR imaging in vivo with FTPA

    International Nuclear Information System (INIS)

    Iriguchi, N.; Miyazaki, T.; Hasegawa, J.; Yamamoto, T.; Yamai, S.; Veshima, Y.; Iwasaki, A.; Toyoshima, H.; Maki, T.

    1986-01-01

    Perfluorotripropylamine (FTPA), together with perfluorodecalin (FDC), makes a blood substitute which has been known to be clinically safe for certain applications. A 1-m-bore, 2-T system (Asahi Mark-J Super 200) was used to image a young rabbit. After intravenous administration of FTPA emulsion, F-19 imaging was carried out. One hour after FTPA administration, a faint but certain image was obtained. Twenty-four hours after the administration of FTPA. the liver, spleen, and bone marrow were clearly recognized. Each image was obtained in 2 minutes

  13. Initial results of hypoxia imaging using 1-{alpha}-d-(5-deoxy-5-[{sup 18}F]-fluoroarabinofuranosyl)-2-nitroimidazole ({sup 18}F-FAZA)

    Energy Technology Data Exchange (ETDEWEB)

    Postema, Ernst J.; McEwan, Alexander J.B.; Riauka, Terence A.; Kumar, Piyush; Richmond, Dacia A.; Abrams, Douglas N. [University of Alberta, Department of Oncology, Edmonton, Alberta (Canada); Wiebe, Leonard I. [University of Alberta, Faculty of Pharmacy and Pharmaceutical Sciences, Edmonton, Alberta (Canada)

    2009-10-15

    Tumour hypoxia is thought to play a significant role in the outcome of solid tumour therapy. Positron emission tomography (PET) is the best-validated noninvasive technique able to demonstrate the presence of hypoxia in vivo. The locally developed PET tracer for imaging hypoxia, 1-{alpha}-d-(5-deoxy-5-[{sup 18}F]-fluoroarabinofuranosyl)-2-nitroimidazole ({sup 18}F-FAZA), has been shown to accumulate in experimental models of tumour hypoxia and to clear rapidly from the circulation and nonhypoxic tissues. The safety and general biodistribution patterns of this radiopharmaceutical in patients with squamous cell carcinoma of the head and neck (HNSCC), small-cell lung cancer (SCLC) or non-small-cell lung cancer (NSCLC), malignant lymphoma, and high-grade gliomas, were demonstrated in this study. Patients with known primary or suspected metastatic HNSCC, SCLC or NSCLC, malignant lymphoma or high-grade gliomas were dosed with 5.2 MBq/kg of {sup 18}F-FAZA, then scanned 2-3 h after injection using a PET or PET/CT scanner. Images were interpreted by three experienced nuclear medicine physicians. The location and relative uptake scores (graded 0 to 4) of normal and abnormal {sup 18}F-FAZA biodistribution patterns, the calculated tumour-to-background (T/B) ratio, and the maximum standardized uptake value were recorded. Included in the study were 50 patients (32 men, 18 women). All seven patients with high-grade gliomas showed very high uptake of {sup 18}F-FAZA in the primary tumour. In six out of nine patients with HNSCC, clear uptake of {sup 18}F-FAZA was observed in the primary tumour and/or the lymph nodes in the neck. Of the 21 lymphoma patients (15 with non-Hodgkin's lymphoma and 6 with Hodgkin's disease), 3 demonstrated moderate lymphoma-related uptake. Of the 13 lung cancer patients (12 NSCLC, 1 SCLC), 7 had increased {sup 18}F-FAZA uptake in the primary lung tumour. No side effects of the administration of {sup 18}F-FAZA were observed. This study suggests

  14. Synthesis and evaluation of 18f-labeled benzylideneaniline derivatives as new biomarkers for β-amyloid imaging in Alzheimer's disease

    International Nuclear Information System (INIS)

    B, Rai Ganeaha; Jeong, Jae Min; Lee, Yun Sang; Chang, Young Soo; Kim, Young Ju; Kim, Hyung Woo; Lee, Dong Soo; Chung, June Key; Lee, Myung Chul

    2005-01-01

    Noninvasive early detection of the Aβ plaques in Alzheimer's disease (AD) brain may be useful tool for the treatment of AD patients. We herein describe the synthesis of 18 F-labeled benzylideneaniline derivatives utilizing a novel labeling approach for imaging Aβ plaques in AD patients. Condensation of [ 18 F] 4-fluorobenzaldehyde with various aromatic amines afforded 18 F-labeled benzylideneaniline derivatives. The biodistribution of 18F-Iabeled benzylideneaniline derivatives was studied with ICR male mice. The binding affinities of the cold compounds to Aβ (1-40) were determined using [ 125 I] 2-(3'-iodo-4-methylaminophenyl) benzothiazole as a reference standard. The radiochemical yields were 32-44% and radiochemical purities were above 99% after purification. Log P values of the compounds were 1.56-1.58. Some of the benzylideneaniline derivatives showed relatively high binding affinity to Aβ (1-40) aggregates (Ki 149-304 nM). The 18 F-labeled benzylideneaniline derivatives displayed high brain uptake ratio in normal mice (2.9-24.93). The study suggests that these 18 F-labeled compounds may be suitable for Aβ plaque imaging in AD patients

  15. LiCa{sub 4}Si{sub 4}N{sub 8}F and LiSr{sub 4}Si{sub 4}N{sub 8}F. Nitridosilicate fluorides with a BCT-zeolite-type network structure

    Energy Technology Data Exchange (ETDEWEB)

    Horky, Katrin; Schnick, Wolfgang [Department of Chemistry, Inorganic Solid-State, Chemistry, University of Munich (LMU), Butenandtstrasse 5-13, 81377, Munich (Germany)

    2017-02-17

    LiCa{sub 4}Si{sub 4}N{sub 8}F and LiSr{sub 4}Si{sub 4}N{sub 8}F were synthesized from Si{sub 3}N{sub 4}, LiNH{sub 2}, CaH{sub 2}/SrH{sub 2}, and LiF through a metathesis reaction in a radiofrequency furnace. The crystal structures of both compounds were solved and refined on the basis of single-crystal X-ray diffraction data [LiCa{sub 4}Si{sub 4}N{sub 8}F: P2{sub 1}/c (no. 14), a = 10.5108(3), b = 9.0217(3), c = 10.3574(3) Aa, β = 117.0152(10) , R{sub 1} = 0.0422, wR{sub 2} = 0.0724, Z = 4; LiSr{sub 4}Si{sub 4}N{sub 8}F: P4nc (no. 104), a = 9.3118(4), b = 9.3118(4), c = 5.5216(2) Aa, R{sub 1} = 0.0160, wR{sub 2} = 0.0388, Z = 2]. The silicate substructure of both compounds is built up of vertex-sharing SiN{sub 4} tetrahedra, thereby forming a structure analogous to the BCT zeolite with Ca{sup 2+}/Sr{sup 2+}, Li{sup +}, and F{sup -} ions filling the voids. The crystal structure of LiSr{sub 4}Si{sub 4}N{sub 8}F is homeotypic with that of Li{sub 2}Sr{sub 4}Si{sub 4}N{sub 8}O as it exhibits the same zeolite-type [SiN{sub 2}]{sup 2-} framework, but incorporates LiF instead of Li{sub 2}O. In contrast to the respective Sr compound, LiCa{sub 4}Si{sub 4}N{sub 8}F shows a distortion of the BCT-zeolite-type network as well as an additional site for F. Both F sites in LiCa{sub 4}Si{sub 4}N{sub 8}F exhibit different coordination spheres to LiSr{sub 4}Si{sub 4}N{sub 8}F. The title compounds are the first reported lithium alkaline-earth nitridosilicates containing fluorine. The crystal structures were confirmed by lattice-energy calculations (MAPLE), energy-dispersive X-ray spectroscopy (EDX) measurements, and powder X-ray diffraction. IR spectra confirmed the absence of N-H bonds. (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  16. Application of nonlinear phenomena induced by focused ultrasound to bone imaging.

    Science.gov (United States)

    Callé, Samuel; Remenieras, Jean-Pierre; Bou Matar, Olivier; Defontaine, Marielle; Patat, Frederic

    2003-03-01

    A tissue deformability image is obtained with the vibroacoustography imaging method using mechanical low-frequency (LF) excitation. This ultrasonic excitation is created locally by means of a focused annular array emitting two primary beams at two close frequencies, f(1) and f(2) (f(2) = f(1) + f(LF)). The LF acoustic emission resulting from the vibration of the medium is detected by a sensitive hydrophone and then used to form the image. This noninvasive imaging method was demonstrated in this study to be suitable for bone imaging, with x and y transverse resolutions less than 300 micro m. Two bone sites susceptible to demineralization were tested: the calcaneus and the neck of the femur. The vibroacoustic method provides valuable ultrasonic images regarding the structure and the elastic properties of bone tissue. Correlation was made between vibroacoustic bone images, performed in vitro, and images acquired by other imaging methods (i.e., bone ultrasound attenuation and x-ray computerized tomography (CT)). Moreover, the amplitudes of vibroacoustic signals radiating from phosphocalcic ceramic samples (bone substitute) of different porosity were evaluated. The good correlation between these results and the description of our images and the quality of vibroacoustic images indicate that bone decalcification could be detected using vibroacoustography.

  17. 18F-labelling of oligonucleotides using succinimido 4-[18F]fluorobenzoat

    International Nuclear Information System (INIS)

    Hedberg, Elisabeth; Laangstroem, Bengt

    1998-01-01

    A general method for the labelling of oligodeoxynucleotide and oligonucleoside phosphorothioates in the 5'-position with the positron-emitting radionuclide 18 F (t 1/2 = 110 min) is described. The label was incorporated by the reaction of succinimido 4 -[ 18 F]fluorobenzoate 4 with oligonucleotides (18- and 20-mers) modified in the 5'-position with a hexylamine linker. Oligodeoxynucleotides 5'-GCT,AAG,CGA,TGC,CTC,CGT-3' (MTCa) and 5'-GAA,CCT,CTG,AGA,GTT,CAT,CT-3' (CROa) were labelled in 20±3 % (MTCa) and 13±3 % (CROa) radiochemical yields (non-isolated, decay-corrected and based on 4). Oligonucleoside phosphorotioates MTCa (S-MTCa) and CROa (S-CROa) were labelled in 9 and 7% isolated radiochemical yield, respectively (decay-corrected and based on 4). Labelled oligonucleotides and phosphorothioate analogues were separated from their unlabelled counterparts using reversed-phase perfusion chromatography. The molecular mass of a labelled oligonucleotide CROa was determined by ESI-MS after a mixed 18 F/ 19 F fluorobenzoate labelling experiment and corresponded with the expected structure. (au)

  18. Feasibility of an intracranial EEG-fMRI protocol at 3T: risk assessment and image quality.

    Science.gov (United States)

    Boucousis, Shannon M; Beers, Craig A; Cunningham, Cameron J B; Gaxiola-Valdez, Ismael; Pittman, Daniel J; Goodyear, Bradley G; Federico, Paolo

    2012-11-15

    Integrating intracranial EEG (iEEG) with functional MRI (iEEG-fMRI) may help elucidate mechanisms underlying the generation of seizures. However, the introduction of iEEG electrodes in the MR environment has inherent risk and data quality implications that require consideration prior to clinical use. Previous studies of subdural and depth electrodes have confirmed low risk under specific circumstances at 1.5T and 3T. However, no studies have assessed risk and image quality related to the feasibility of a full iEEG-fMRI protocol. To this end, commercially available platinum subdural grid/strip electrodes (4×5 grid or 1×8 strip) and 4 or 6-contact depth electrodes were secured to the surface of a custom-made phantom mimicking the conductivity of the human brain. Electrode displacement, temperature increase of electrodes and surrounding phantom material, and voltage fluctuations in electrode contacts were measured in a GE Discovery MR750 3T MR scanner during a variety of imaging sequences, typical of an iEEG-fMRI protocol. An electrode grid was also used to quantify the spatial extent of susceptibility artifact. The spatial extent of susceptibility artifact in the presence of an electrode was also assessed for typical imaging parameters that maximize BOLD sensitivity at 3T (TR=1500 ms; TE=30 ms; slice thickness=4mm; matrix=64×64; field-of-view=24 cm). Under standard conditions, all electrodes exhibited no measurable displacement and no clinically significant temperature increase (2.0°C) that in some cases exceeded 10°C. Induced voltages in the frequency range that could elicit neuronal stimulation (<10 kHz) were well below the threshold of 100 mV. fMRI signal intensity was significantly reduced within 20mm of the electrodes for the imaging parameters used in this study. Thus, for the conditions tested, a full iEEG-fMRI protocol poses a low risk at 3T; however, fMRI sensitivity may be reduced immediately adjacent to the electrodes. In addition, high SAR sequences

  19. Investigation of the multiphotonic excitation processes of the 4f2 5d configuration in LiYF4, LiLuF4 and BaY2F8 crystals doped with trivalent neodymium

    International Nuclear Information System (INIS)

    Librantz, Andre Felipe Henriques

    2004-01-01

    Ultraviolet (UV) fluorescence of Nd 3+ ions induced by multistep laser excitation was investigated in Nd-doped LiYF 4 (YLF), LiLuF 4 (LLF) and BaY 2 F 8 (BaYF) crystals using a technique of time-resolved spectroscopy. The observed UV luminescence was due to transitions between the bottom of 4f 2 5d configuration and the 4f 3 states of Nd 3+ ions. The lower excited state 4f 2 ( 3 H)5d [ 4 K 11/2 ] was reached by three stepwise absorptions of photons at 521 nm (green) and 478 nm (blue) of a short pulse laser excitation. The three sequential absorptions at 478 nm constitutes a new multiphoton excitation process of Nd 3+ in these crystals with the following excitation sequence: 4 I 9/2 + hv(480 nm)→ 2 G(1) 9/2 + hv(480 nm)→ 2 F(2) 7/2 + hv(480 nm)→ 4f 2 ( 3 H)5d [ 4 K 9/2 ] (excited state at ∼ 63000 cm -1 ). The observed UV emissions from [ 4 K 11/2 ] state have a lifetime of 35 ns (parity allowed) and are: broadband in contrast to UV emissions from 4f 3 configuration, which are also present in the luminescence investigation but having longer lifetime (8 μs) and structures composed of narrow lines. The excitation spectrum of fast UV luminescence exhibited different structure depending on the excitation geometry (σ or π) with respect to the c-axis of the crystal. It was seen two new emissions from [ 4 K 11/2 ] and 2 F(2) 5/2 states near 528 nm, which modified the branching ratio of the bottom of the 4f 2 5d configuration (∼ 55500 cm -1 for the YLF and LLF crystals and ∼-53700 cm -1 for the BaYF crystal). The equivalent cross-section of three and two excitation process was estimated at 521 nm by solving the rate equations of the system under short laser excitation, which leads us to infer that is possible to have laser action under pulsed laser pumping with intensity below the crystal damage threshold. (author)

  20. 18F-FDG PET imaging before and after capsulotomy in obsessive-compulsive disorder

    International Nuclear Information System (INIS)

    Guan Yihui; Sun Bomin; Zhang Haiying; Lin Xiangtong; Zuo Chuantao; Zhao Jun; Liu Yongchang

    2001-01-01

    Objective: To evaluate the therapeutic effect of surgery in obsessive-compulsive disorder (OCD) patients with 18 F-FDG PET imaging. Methods: 18 F-fluorodeoxyglucose (FDG)-PET images were obtained in 9 patients with OCD (6 male and 3 female) before and after 3 to 4 weeks of bilateral capsulotomy, PET images were also performed in 10 controls. Each OCD patient was also evaluated both before and after the surgery by various neuropsychiatric tests including Y-BOCS, HAMA and HAMD. Results: Compare with normal controls, 9 cases of OCD demonstrated high 18 F-FDG uptake in frontal, cingulate, orbital gyri, caudate and thalamus. After capsulotomy, 6 of 9 cases showed better results, the metabolic ratios were also significant decreased in the following areas: anterior cingule gyrus: right (P < 0.001) left (P < 0.05), caudate nuclei: right (P < 0.01) left (P < 0.05), anterolateral orbital frontal cortex: right (P < 0.01) left (P < 0.05), there is no significant changes in bilateral thalamus. Meanwhile, the OCD scales also have significant decreased values in Y-BOCS (P < 0.05) and HARS (P < 0.001). Conclusions: These results indicated that cingule-striatum-pallidum-thalamic circuit is closely related to OCD, and glucose metabolism in these areas decreases significantly after bilateral capsulotomy

  1. Preclinical Evaluation of 18F-Labeled Anti-HER2 Nanobody Conjugates for Imaging HER2 Receptor Expression by Immuno-PET.

    Science.gov (United States)

    Vaidyanathan, Ganesan; McDougald, Darryl; Choi, Jaeyeon; Koumarianou, Eftychia; Weitzel, Douglas; Osada, Takuya; Lyerly, H Kim; Zalutsky, Michael R

    2016-06-01

    The human growth factor receptor type 2 (HER2) is overexpressed in breast as well as other types of cancer. Immuno-PET, a noninvasive imaging procedure that could assess HER2 status in both primary and metastatic lesions simultaneously, could be a valuable tool for optimizing application of HER2-targeted therapies in individual patients. Herein, we have evaluated the tumor-targeting potential of the 5F7 anti-HER2 Nanobody (single-domain antibody fragment; ∼13 kDa) after (18)F labeling by 2 methods. The 5F7 Nanobody was labeled with (18)F using the novel residualizing label N-succinimidyl 3-((4-(4-(18)F-fluorobutyl)-1H-1,2,3-triazol-1-yl)methyl)-5-(guanidinomethyl)benzoate ((18)F-SFBTMGMB; (18)F-RL-I) and also via the most commonly used (18)F protein-labeling prosthetic agent N-succinimidyl 3-(18)F-fluorobenzoate ((18)F-SFB). For comparison, 5F7 Nanobody was also labeled using the residualizing radioiodination agent N-succinimidyl 4-guanidinomethyl-3-(125)I-iodobenzoate ((125)I-SGMIB). Paired-label ((18)F/(125)I) internalization assays and biodistribution studies were performed on HER2-expressing BT474M1 breast carcinoma cells and in mice with BT474M1 subcutaneous xenografts, respectively. Small-animal PET/CT imaging of 5F7 Nanobody labeled using (18)F-RL-I also was performed. Internalization assays indicated that intracellularly retained radioactivity for (18)F-RL-I-5F7 was similar to that for coincubated (125)I-SGMIB-5F7, whereas that for (18)F-SFB-5F7 was lower than coincubated (125)I-SGMIB-5F7 and decreased with time. BT474M1 tumor uptake of (18)F-RL-I-5F7 was 28.97 ± 3.88 percentage injected dose per gram of tissue (%ID/g) at 1 h and 36.28 ± 14.10 %ID/g at 2 h, reduced by more than 90% on blocking with trastuzumab, indicating HER2 specificity of uptake, and was also 26%-28% higher (P < 0.05) than that of (18)F-SFB-5F7. At 2 h, the tumor-to-blood ratio for (18)F-RL-I-5F7 (47.4 ± 13.1) was significantly higher (P < 0.05) than for (18)F-SFB-5F7 (25.4 ± 10

  2. Solvothermal indium fluoride chemistry: Syntheses and crystal structures of K5In3F14, β-(NH4)3InF6 and [NH4]3[C6H21N4]2[In4F21

    International Nuclear Information System (INIS)

    Jayasundera, Anil C.A.; Goff, Richard J.; Li Yang; Finch, Adrian A.; Lightfoot, Philip

    2010-01-01

    The solvothermal syntheses and crystal structures of three indium fluorides are presented. K 5 In 3 F 14 (1) and β-(NH 4 ) 3 InF 6 (2) are variants on known inorganic structure types chiolite and cryolite, respectively, with the latter exhibiting a complex and apparently novel structural distortion. [NH 4 ] 3 [C 6 H 21 N 4 ] 2 [In 4 F 21 ] (3) represents a new hybrid composition displaying a unique trimeric metal fluoride building unit. - Graphical abstract: Solvothermal synthesis has been used to prepare three indium fluorides, including a novel hybrid material containing a unique [In 3 F 15 ] trimer templated by tren.

  3. A 4-channel 3 Tesla phased array receive coil for awake rhesus monkey fMRI and diffusion MRI experiments.

    Science.gov (United States)

    Khachaturian, Mark Haig

    2010-01-01

    Awake monkey fMRI and diffusion MRI combined with conventional neuroscience techniques has the potential to study the structural and functional neural network. The majority of monkey fMRI and diffusion MRI experiments are performed with single coils which suffer from severe EPI distortions which limit resolution. By constructing phased array coils for monkey MRI studies, gains in SNR and anatomical accuracy (i.e., reduction of EPI distortions) can be achieved using parallel imaging. The major challenges associated with constructing phased array coils for monkeys are the variation in head size and space constraints. Here, we apply phased array technology to a 4-channel phased array coil capable of improving the resolution and image quality of full brain awake monkey fMRI and diffusion MRI experiments. The phased array coil is that can adapt to different rhesus monkey head sizes (ages 4-8) and fits in the limited space provided by monkey stereotactic equipment and provides SNR gains in primary visual cortex and anatomical accuracy in conjunction with parallel imaging and improves resolution in fMRI experiments by a factor of 2 (1.25 mm to 1.0 mm isotropic) and diffusion MRI experiments by a factor of 4 (1.5 mm to 0.9 mm isotropic).

  4. Acoustic radiation- and streaming-induced microparticle velocities determined by microparticle image velocimetry in an ultrasound symmetry plane

    DEFF Research Database (Denmark)

    Barnkob, Rune; Augustsson, Per; Laurell, Thomas

    2012-01-01

    We present microparticle image velocimetry measurements of suspended microparticles of diameters from 0.6 to 10μm undergoing acoustophoresis in an ultrasound symmetry plane in a microchannel. The motion of the smallest particles is dominated by the Stokes drag from the induced acoustic streaming...

  5. NH4HCO3 gas-generating liposomal nanoparticle for photoacoustic imaging in breast cancer

    Directory of Open Access Journals (Sweden)

    Xia J

    2017-03-01

    Full Text Available Jizhu Xia, Gang Feng, Xiaorong Xia, Lan Hao, Zhigang Wang Chongqing Key Laboratory of Ultrasound Molecular Imaging, Department of Ultrasound, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, People’s Republic of China Abstract: In this study, we have developed a biodegradable nanomaterial for photoacoustic imaging (PAI. Its biodegradation products can be fully eliminated from a living organism. It is a gas-generating nanoparticle of liposome-encapsulating ammonium bicarbonate (NH4HCO3 solution, which is safe, effective, inexpensive, and free of side effects. When lasers irradiate these nanoparticles, NH4HCO3 decomposes to produce CO2, which can absorb much of the light energy under laser irradiation with a specific wavelength, and then expand under heat to generate a thermal acoustic wave. An acoustic detector can detect this wave and show it as a photoacoustic signal on a display screen. The intensity of the photoacoustic signal is enhanced corresponding to an increase in time, concentration, and temperature. During in vivo testing, nanoparticles were injected into tumor-bearing nude mice through the caudal vein, and photoacoustic signals were detected from the tumor, reaching a peak in 4 h, and then gradually disappearing. There was no damage to the skin or subcutaneous tissue from laser radiation. Our developed gas-generating nanomaterial, NH4HCO3 nanomaterial, is feasible, effective, safe, and inexpensive. Therefore, it is a promising material to be used in clinical PAI. Keywords: Photoacoustic tomography, CO2, NH4HCO3, contrast agent, cancer

  6. Ion acoustic waves in one- and two-negative ion species plasmas

    International Nuclear Information System (INIS)

    Ichiki, Ryuta; Shindo, Masako; Yoshimura, Shinji; Watanabe, Tsuguhiro; Kawai, Yoshinobu

    2001-01-01

    Ion acoustic waves in multi-ion plasmas including two negative ion species are investigated both numerically and experimentally. Numerically, the kinetic dispersion relation in two-negative ion plasmas is investigated. There are three modes of the ion acoustic waves in two-negative ion plasmas. In an Ar + -F - -SF 6 - plasma, only one of the three modes is dominant, regardless of the values of the electron and the ion temperatures. In a Xe + -F - -SF 6 - plasma, on the other hand, two modes can be important for a certain range of the electron-ion temperature ratio. The results also imply the possibility of the coexistence of the fast mode and the slow mode in one-negative ion plasmas. Experimentally, ion acoustic waves are observed in an Ar + -F - -SF 6 - plasma and are found to show a mode transition that agrees with the theoretical prediction for one of the three ion acoustic modes

  7. 18F-F.D.G. PET imaging of infection and inflammation: intestinal, prosthesis replacements, fibrosis, sarcoidosis, tuberculosis.

    International Nuclear Information System (INIS)

    Fernandez, A.; Cortes, M.; Caresia, A.P.; Juan, R. de; Vidaller, A.; Mana, J.; Martinez-Yelamos, S.; Gamez, C.

    2008-01-01

    Nuclear medicine plays an important role in the evaluation of infection and inflammation. A variety of diagnostic methods are available for imaging this inflammation and infection, most notably computed tomography, 68 Ga scintigraphy or radionuclide labeled leucocytes. Fluorine 18 fluorodeoxyglucose ( 18 F-F.D.G.) is a readily available radiotracer that offers rapid, exquisitely sensitive high-resolution images by positron emission tomography (PET). Inflammation can be acute or chronic, the former showing predominantly neutrophilic granulocyte infiltrates, whereas in the latter, macrophages predominate. F.D.G. uptake in infection is based on the fact that mononuclear cells and granulocytes use large quantities of glucose by way of the hexose monophosphate shunts. 18 F-F.D.G. PET accurately helps diagnose spinal osteomyelitis, diabetic foot and in inflammatory conditions such as sarcoidosis and tuberculosis.(it appears to be useful for defining the extent of disease and monitoring response to treatment). 18 F-F.D.G. PET can also help localize the source of fever of undetermined origin, thereby guiding additional testing. 18 F-F.D.G. PET may be of limited usefulness in postoperative patients and in patients with a failed joint prosthesis or bowel inflammatory disease. In this review, we will focus on the role of 18 F-F.D.G. PET in the management of patients with inflammation or suspected or confirmed infection

  8. Modular Towed Acoustic Sonar Array

    Science.gov (United States)

    2014-02-04

    Dkt . No...d 11 5 11 0c 11 0d 11 5 14 0 16 0’ 1 60 ’’ 12 0 14 0 12 0 14 0 13 0 14 0 12 0 13 0 12 0 12 0 13 0 14 0 16 0 10 0 d 2 d 3 Dkt . No. 102060 Application...of Non-Acoustic Sensors in Second Sensor Array Dkt . No. 102060 Application No. ?? REPLACEMENT SHEET? /3 1st DRAFT 3 F IG . 3 11 5 16 4 16 8 16 2 16 6 11 5 1 50 11 0b 18 0 17 0 16 6a 16 4a 18 0 10 0 11 0a 15 0

  9. Ultrasonic superlensing jets and acoustic-fork sheets

    Energy Technology Data Exchange (ETDEWEB)

    Mitri, F.G., E-mail: F.G.Mitri@ieee.org

    2017-05-18

    Focusing acoustical (and optical) beams beyond the diffraction limit has remained a major challenge in imaging instruments and systems, until recent advances on “hyper” or “super” lensing and higher-resolution imaging techniques have shown the counterintuitive violation of this rule under certain circumstances. Nonetheless, the proposed technologies of super-resolution acoustical focusing beyond the diffraction barrier require complex tools such as artificially engineered metamaterials, and other hardware equipment that may not be easily synthesized or manufactured. The present contribution therefore suggests a simple and reliable method of using a sound-penetrable circular cylinder lens illuminated by a nonparaxial Gaussian acoustical sheet (i.e. finite beam in 2D) to produce non-evanescent ultrasonic superlensing jets (or bullets) and acoustical ‘snail-fork’ shaped wavefronts with limited diffraction. The generalized (near-field) scattering theory for acoustical sheets of arbitrary wavefronts and incidence is utilized to synthesize the incident beam based upon the angular spectrum decomposition method and the multipole expansion method in cylindrical wave functions to compute the scattered pressure around the cylinder with particular emphasis on its physical properties. The results show that depending on the beam and lens parameters, a tight focusing (with dimensions much smaller than the beam waist) can be achieved. Subwavelength resolution can be also achieved by selecting a lens material with a speed of sound exceeding that of the host fluid medium. The ultrasonic superlensing jets provide the impetus to develop improved subwavelength microscopy and acoustical image-slicing systems, cell lysis and surgery, and photoacoustic imaging to name a few examples. Moreover, an acoustical fork-sheet generation may open innovative avenues in reconfigurable on-chip micro/nanoparticle tweezers and surface acoustic waves devices. - Highlights: • Ultrasonic

  10. Transcytosis of F4 fimbriae by villous and dome epithelia in F4-receptor positive pigs supports importance of receptor-dependent endocytosis in oral immunization strategies.

    Science.gov (United States)

    Snoeck, Veerle; Van den Broeck, Wim; De Colvenaer, Veerle; Verdonck, Frank; Goddeeris, Bruno; Cox, Eric

    2008-07-15

    Very few antigens have been described that induce an intestinal immunity when given orally. Our laboratory demonstrated that oral administration of isolated F4 (K88) fimbriae of Escherichia coli to F4-receptor positive (F4R(+)) pigs induces protective mucosal immunity against challenge infection. However, presence of F4-receptors (F4R) on villous enterocytes is a prerequisite for inducing the immune response, as no F4-specific antibody-secreting cells (ASC) can be induced in F4R(-) pigs. In this study, the in vivo binding of isolated F4 fimbriae (F4) to the gut epithelium was examined in F4R(+) and F4R(-) pigs. It was further investigated whether binding of F4 to the F4R results in endocytosis in and translocation across the gut epithelium using microscopy. F4 did not adhere to the intestinal epithelium of F4R(-) pigs, whereas it strongly adhered to the villous epithelium and the follicle-associated epithelium (FAE) of the jejunum and ileum of F4R(+) pigs. Following binding to F4R, F4 was endocytosed by villous enterocytes, follicle-associated enterocytes and M cells. Transcytosis of F4 across the epithelium resulted in the appearance of F4 in the lamina propria and dome region of the jejunal and ileal PP. This is the first study showing transcytosis of fimbriae across the gut epithelium. This receptor-dependent transcytosis can explain the success of F4 fimbriae as oral immunogen for inducing protective immunity in F4R(+) pigs strengthening the importance of receptor-dependent endocytosis and translocation in oral vaccine strategies. Further identification of the receptor responsible for this transport is in progress.

  11. Clinical value of 18F-FDG coincidence imaging for diagnosis of nasopharyngeal carcinoma

    International Nuclear Information System (INIS)

    Ning Yanli; Lou Cen; Huang Zhongke; Shi Guohua; Chen Dongfang; Mu Da

    2012-01-01

    .05). T/NT ratios and tumor volumes between groups of different clinical stages (H=5.895 and 1.855, both P>0.05) and T stages (H=4.756 and 0.270, both P>0.05) were significantly different. Conclusions: 18 F-FDG coincidence imaging plays a role in the diagnosis of nasopharyngeal carcinoma. The cut-off value of T/NT ratio is helpful for the prognosis prediction of nasopharyngeal carcinoma. (authors)

  12. Evaluation of [18F]-ATRi as PET tracer for in vivo imaging of ATR in mouse models of brain cancer

    International Nuclear Information System (INIS)

    Carlucci, Giuseppe; Carney, Brandon; Sadique, Ahmad; Vansteene, Axel; Tang, Jun; Reiner, Thomas

    2017-01-01

    Rationale: Ataxia telangiectasia and Rad3-related (ATR) threonine serine kinase is one of the key elements in orchestrating the DNA damage response (DDR). As such, inhibition of ATR can amplify the effects of chemo- and radiation-therapy, and several ATR inhibitors (ATRi) have already undergone clinical testing in cancer. For more accurate patient selection, monitoring and staging, real-time in vivo imaging of ATR could be invaluable; the development of appropriate imaging agents has remained a major challenge. Methods: 3-amino-N-(4-[ 18 F]phenyl)-6-(4-(methylsulfonyl)phenyl) pyrazine-2-carboxamide ([ 18 F]-ATRi), a close analogue of Ve-821, (a clinical ATRi candidate), was readily accomplished similarly to already established synthetic procedures. Structurally, 18 F was introduced at the 4-position of the aromatic ring of Ve-821 for generating a labeled ATR inhibitor. In vitro experiments were conducted in U251 MG glioblastoma cell lines and ex vivo biodistribution were performed in subcutaneous U251 MG xenograft bearing athymic nude mice following microPET imaging. Results: [ 18 F]-ATRi has a similar pharmacokinetic profile to that of Ve-821. Using an U251 MG glioblastoma mouse model, we evaluated the in vivo binding efficiency of [ 18 F]-ATRi. Blood and tumor showed a statistically significant difference between mice injected with only the probe or following blocking experiment with Ve-821 (1.48 ± 0.40%ID/g vs. 0.46 ± 0.12%ID/g in tumor and 1.85 ± 0.47%ID/g vs. 0.84 ± 0.3%ID/g in blood respectively). Conclusions: [ 18 F]-ATRi represents the first 18 F positron emission tomography (PET) ATR imaging agent, and is designed on a low nanomolar and clinically relevant ATR inhibitor.

  13. {sup 18}F-FDOPA PET/CT imaging of insulinoma revisited

    Energy Technology Data Exchange (ETDEWEB)

    Imperiale, Alessio; Namer, Izzie-Jacques [University Hospitals of Strasbourg, Department of Biophysics and Nuclear Medicine, Strasbourg (France); University of Strasbourg/CNRS and FMTS, Faculty of Medicine, ICube - UMR 7357, Strasbourg (France); Sebag, Frederic [Aix-Marseille University, Department of Endocrine Surgery, La Timone University Hospital, Marseille (France); Vix, Michel [University of Strasbourg, Department of General, Digestive, and Endocrine Surgery, IRCAD-IHU, Strasbourg (France); Castinetti, Frederic [Aix-Marseille University, Department of Endocrinology, Diabetes and Metabolic Disorders, La Timone University Hospital, Marseille (France); Kessler, Laurence; Moreau, Francois [University of Strasbourg, Department of Diabetology, University Hospital of Strasbourg, Strasbourg (France); Bachellier, Philippe [University Hospitals of Strasbourg, Department of Visceral Surgery and Transplantation, Strasbourg (France); Guillet, Benjamin; Mundler, Olivier [Aix-Marseille University, Department of Nuclear Medicine, La Timone University Hospital, CERIMED, Marseille (France); Taieb, David [Aix-Marseille University, Department of Nuclear Medicine, La Timone University Hospital, CERIMED, Marseille (France); Aix-Marseille University, Biophysics and Nuclear Medecine, La Timone University Hospital, European Center for Research in Medical Imaging, Marseille (France)

    2014-11-01

    {sup 18}F-FDOPA PET imaging is increasingly used in the work-up of patients with neuroendocrine tumours. It has been shown to be of limited value in localizing pancreatic insulin-secreting tumours in adults with hyperinsulinaemic hypoglycaemia (HH) mainly due to {sup 18}F-FDOPA uptake by the whole pancreatic gland. The objective of this study was to review our experience with {sup 18}F-FDOPA PET/CT imaging with carbidopa (CD) premedication in patients with HH in comparison with PET/CT studies performed without CD premedication in an independent population. A retrospective study including 16 HH patients who were investigated between January 2011 and December 2013 using {sup 18}F-FDOPA PET/CT (17 examinations) in two academic endocrine tumour centres was conducted. All PET/CT examinations were performed under CD premedication (200 mg orally, 1 - 2 h prior to tracer injection). The PET/CT acquisition protocol included an early acquisition (5 min after {sup 18}F-FDOPA injection) centred over the upper abdomen and a delayed whole-body acquisition starting 20 - 30 min later. An independent series of eight consecutive patients with HH and investigated before 2011 were considered for comparison. All patients had a reference whole-body PET/CT scan performed about 1 h after {sup 18}F-FDOPA injection. In all cases, PET/CT was performed without CD premedication. In the study group, {sup 18}F-FDOPA PET/CT with CD premedication was positive in 8 out of 11 patients with histologically proven insulinoma (73 %). All {sup 18}F-FDOPA PET/CT-avid insulinomas were detected on early images and 5 of 11 (45 %) on delayed ones. The tumour/normal pancreas uptake ratio was not significantly different between early and delayed acquisitions. Considering all patients with HH, including those without imaging evidence of disease, the detection rate of the primary lesions using CD-assisted {sup 18}F-FDOPA PET/CT was 53 %, showing 9 insulinomas in 17 studies performed. In the control group (without

  14. Experimental study of the molecular mechanisms of myocardial ischemic memory with 18F-FDG PET/CT imaging

    International Nuclear Information System (INIS)

    Xie Boqia; Yang Minfu; Ye Jue; Yang Zihe; Dou Kefei; Tian Yi; Han Chunlei

    2012-01-01

    This study was aimed to explore whether the changes of mRNA and the existence and duration of ischemic 18 F-FDG uptake correlate with the extent of myocardial ischemia in ischemia-reperfusion canine model. The 20-minute (n= 4) and 40-minute (n=4) coronary artery occlusion followed by 24 h of open-artery reperfusion in canine model were per- formed. All dogs underwent fasting (>12 h) dynamic 18 F-FDG PET/CT and 99 Tc m -MIBI SPECT imaging at baseline, 1 h and 24 h after reperfusion. When all imaging were completed, myocardial samples from the ischemic and nonischemic region were obtained, and the mRNA expression of glucose transporter-l (GLUT-1), glucose transporter-4 (GLUT-4), and heart-fatty acid binding protein (H-FABP) were estimated by Real Time PCR. There was no difference in the ratio of hypoperfused region/nomoperfused region of 18 F-FDG up- take between the 20-minute group and 40-minute group at baseline. When examined at 1 h, increased 18 F-FDG uptake was observed in the 40-minute group. When estimated at 24 h, only the 40-minute group showed slightly higher 18 F-FDG uptake than baseline, whereas no such difference was demonstrated in the 20-minute group. Similar mRNA expression of GLUT-1, GLUT-4 and H-FABP were demonstrated in the nonischemic regions between the 2 groups, whereas increased expressions of GLUT-1 and GLUT-4, and decreased H-FABP mRNA were demonstrated in the ischemic regions. The changes of mRNA expression were more obvious in the 40 minute group than in the 20-minute group. The results showed that the existence and persistent period of ischemic 18 F-FDG uptake (ischemic memory) was correlated with the extent of myocardial ischemia. (authors)

  15. Acoustic Characteristics of Simulated Respiratory-Induced Vocal Tremor

    Science.gov (United States)

    Lester, Rosemary A.; Story, Brad H.

    2013-01-01

    Purpose: The purpose of this study was to investigate the relation of respiratory forced oscillation to the acoustic characteristics of vocal tremor. Method: Acoustical analyses were performed to determine the characteristics of the intensity and fundamental frequency (F[subscript 0]) for speech samples obtained by Farinella, Hixon, Hoit, Story,…

  16. MO-AB-BRA-05: [18F]NaF PET/CT Imaging Biomarkers in Metastatic Prostate Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Harmon, S; Perk, T; Lin, C; Eickhoff, J; Perlman, S; Liu, G; Jeraj, R [University of Wisconsin Madison, Madison, WI (United States); Choyke, P; Dahut, W; Apolo, A [National Cancer Institute at the National Institutes of Health, Bethesda, MD (United States); Humm, J; Larson, S; Morris, MJ [Memorial Sloan-Kettering Cancer Center, New York, NY (United States)

    2016-06-15

    Purpose: Clinical use of {sup 18}F-Sodium Fluoride (NaF) PET/CT in metastatic settings often lacks technology to quantitatively measure full disease dynamics due to high tumor burden. This study assesses radiomics-based extraction of NaF PET/CT measures, including global metrics of overall burden and local metrics of disease heterogeneity, in metastatic prostate cancer for correlation to clinical outcomes. Methods: Fifty-six metastatic Castrate-Resistant Prostate Cancer (mCRPC) patients had NaF PET/CT scans performed at baseline and three cycles into chemotherapy (N=16) or androgen-receptor (AR) inhibitors (N=39). A novel technology, Quantitative Total Bone Imaging (QTBI), was used for analysis. Employing hybrid PET/CT segmentation and articulated skeletal-registration, QTBI allows for response assessment of individual lesions. Various SUV metrics were extracted from each lesion (iSUV). Global metrics were extracted from composite lesion-level statistics for each patient (pSUV). Proportion of detected lesions and those with significant response (%-increase or %-decrease) was calculated for each patient based on test-retest limits for iSUV metrics. Cox proportional hazard regression analyses were conducted between imaging metrics and progression-free survival (PFS). Results: Functional burden (pSUV{sub total}) assessed mid-treatment was the strongest univariate predictor of PFS (HR=2.03; p<0.0001). Various global metrics outperformed baseline clinical markers, including fraction of skeletal burden, mean uptake (pSUV{sub mean}), and heterogeneity of average lesion uptake (pSUV{sub hetero}). Of 43 patients with paired baseline/mid-treatment imaging, 40 showed heterogeneity in lesion-level response, containing populations of lesions with both increasing/decreasing metrics. Proportion of lesions with significantly increasing iSUV{sub mean} was highly predictive of clinical PFS (HR=2.0; p=0.0002). Patients exhibiting higher proportion of lesions with decreasing i

  17. Investigation into the Effect of Acoustic Radiation Force and Acoustic Streaming on Particle Patterning in Acoustic Standing Wave Fields

    Directory of Open Access Journals (Sweden)

    Shilei Liu

    2017-07-01

    Full Text Available Acoustic standing waves have been widely used in trapping, patterning, and manipulating particles, whereas one barrier remains: the lack of understanding of force conditions on particles which mainly include acoustic radiation force (ARF and acoustic streaming (AS. In this paper, force conditions on micrometer size polystyrene microspheres in acoustic standing wave fields were investigated. The COMSOL® Mutiphysics particle tracing module was used to numerically simulate force conditions on various particles as a function of time. The velocity of particle movement was experimentally measured using particle imaging velocimetry (PIV. Through experimental and numerical simulation, the functions of ARF and AS in trapping and patterning were analyzed. It is shown that ARF is dominant in trapping and patterning large particles while the impact of AS increases rapidly with decreasing particle size. The combination of using both ARF and AS for medium size particles can obtain different patterns with only using ARF. Findings of the present study will aid the design of acoustic-driven microfluidic devices to increase the diversity of particle patterning.

  18. Investigation into the Effect of Acoustic Radiation Force and Acoustic Streaming on Particle Patterning in Acoustic Standing Wave Fields

    Science.gov (United States)

    Yang, Yanye; Ni, Zhengyang; Guo, Xiasheng; Luo, Linjiao; Tu, Juan; Zhang, Dong

    2017-01-01

    Acoustic standing waves have been widely used in trapping, patterning, and manipulating particles, whereas one barrier remains: the lack of understanding of force conditions on particles which mainly include acoustic radiation force (ARF) and acoustic streaming (AS). In this paper, force conditions on micrometer size polystyrene microspheres in acoustic standing wave fields were investigated. The COMSOL® Mutiphysics particle tracing module was used to numerically simulate force conditions on various particles as a function of time. The velocity of particle movement was experimentally measured using particle imaging velocimetry (PIV). Through experimental and numerical simulation, the functions of ARF and AS in trapping and patterning were analyzed. It is shown that ARF is dominant in trapping and patterning large particles while the impact of AS increases rapidly with decreasing particle size. The combination of using both ARF and AS for medium size particles can obtain different patterns with only using ARF. Findings of the present study will aid the design of acoustic-driven microfluidic devices to increase the diversity of particle patterning. PMID:28753955

  19. Syntheses of two potential dopamine D{sub 4} receptor radioligands: {sup 18}F labelled chromeno[3,4-c]pyridin-5-ones

    Energy Technology Data Exchange (ETDEWEB)

    Gu-Cai Li; Duan-Zhi Yin; Ming-Wei Wang; Deng-Feng Cheng; Yong-Xian Wang [Research Center of Radiopharmaceuticals, Shanghai Inst. of Applied Physics, Chinese Academy of Sciences, Shanghai, SH (China)

    2006-07-01

    The dopamine D{sub 4} receptor is hypothesized to relate with the pathophysiology and pharmacotherapy of schizophrenia while its level in brain regions is much lower and to date no suitable tracer is available for the study of D{sub 4} receptor in vivo. Therefore, selective imaging agents for the D{sub 4} subtype are badly needed. Based on the structure-activity analysis of chromeno[3,4-c]pyridin-5-ones as dopamine D{sub 4} receptor ligands, two fluorine-18 labelled chromeno[3,4-c] pyridin-5-one derivatives, 3-(4-[{sup 18}F]fluorobenzyl)-8-hydroxy-1,2,3,4-tetrahydrochromeno[3,4-c]pyridin-5-one and 3-(4-[{sup 18}F]fluorobenzyl)-8,9-dimethoxy-1,2,3,4-tetrahydrochromeno[3,4-c]pyridin-5-one were synthesized through a two-step one-pot method. Their radiochemical yields were around 19.7% (decay-corrected) and radiochemical purities were higher than 95% with specific activities of about 120 GBq/{mu}mol. (orig.)

  20. Systems and methods for biometric identification using the acoustic properties of the ear canal

    International Nuclear Information System (INIS)

    Bouchard, A.M.; Osbourn, G.C.

    1998-01-01

    The present invention teaches systems and methods for verifying or recognizing a person's identity based on measurements of the acoustic response of the individual's ear canal. The system comprises an acoustic emission device, which emits an acoustic source signal s(t), designated by a computer, into the ear canal of an individual, and an acoustic response detection device, which detects the acoustic response signal f(t). A computer digitizes the response (detected) signal f(t) and stores the data. Computer-implemented algorithms analyze the response signal f(t) to produce ear-canal feature data. The ear-canal feature data obtained during enrollment is stored on the computer, or some other recording medium, to compare the enrollment data with ear-canal feature data produced in a subsequent access attempt, to determine if the individual has previously been enrolled. The system can also be adapted for remote access applications. 5 figs

  1. Systems and methods for biometric identification using the acoustic properties of the ear canal

    Science.gov (United States)

    Bouchard, Ann Marie; Osbourn, Gordon Cecil

    1998-01-01

    The present invention teaches systems and methods for verifying or recognizing a person's identity based on measurements of the acoustic response of the individual's ear canal. The system comprises an acoustic emission device, which emits an acoustic source signal s(t), designated by a computer, into the ear canal of an individual, and an acoustic response detection device, which detects the acoustic response signal f(t). A computer digitizes the response (detected) signal f(t) and stores the data. Computer-implemented algorithms analyze the response signal f(t) to produce ear-canal feature data. The ear-canal feature data obtained during enrollment is stored on the computer, or some other recording medium, to compare the enrollment data with ear-canal feature data produced in a subsequent access attempt, to determine if the individual has previously been enrolled. The system can also be adapted for remote access applications.

  2. 12th Anglo-French Physical Acoustics Conference (AFPAC2013)

    Science.gov (United States)

    2014-04-01

    The Anglo-French Physical Acoustics Conference (AFPAC) had its 12th annual meeting in Villa Clythia, Fréjus, France, from 16th to 18th January 2013. This series of meetings is a collaboration between the Physical Acoustics Group (PAG) of the Institute of Physics and the Groupe d'Acoustique Physique, Sous-marine et UltraSonore (GAPSUS) of the Société Française d'Acoustique. This year, attendees got the opportunity to see the French Riviera with its Mediterranean vegetation covered by a nice thick snow layer. The participants heard 34 excellent oral presentations and saw 3 posters covering an exciting and diverse range of subjects and of frequencies, from ultrasonic wave propagation in chocolate to metamaterials applied to seismic waves for protecting buildings. Among them, invited talks were given by Pr F A Duck ( Enhanced healing by ultrasound: clinical effects and mechanisms), Pr. J-C Valiére, who actually gave two invited talks ( 1. Measurement of audible acoustic particle velocity using laser: Principles, signal processing and applications, 2. Acoustic pots in ancient and medieval buildings: Literary analysis of ancient texts and comparison with recent observations in French churches), Dr P Huthwaite ( Ultrasonic imaging through the resolution of inverse problems), Dr X Lurton ( Underwater acoustic systems on oceanographic research vessels: principles and applications), Dr S Guenneau ( From platonics to seismic metamaterials). For the fifth consecutive year AFPAC is followed by the publication of its proceedings with 12 peer-reviewed papers which cover the most recent research developments in the field of Physical Acoustics in the UK and France. Alain Lhémery (CEA, France) and Nader Saffari (UCL, United Kingdom) French Riviera 12th AFPAC — Villa Clythia, Fréjus (French Riviera), the 17th of January 2013

  3. Reactions UF4 - ClO2F and UF5 - ClO2F

    International Nuclear Information System (INIS)

    Benoit, Raymond; Besnard, Ginette; Hartmanshenn, Olivier; Luce, Michel; Mougin, Jacques; Pelissie, Jean

    1970-02-01

    The study of the reaction UF 4 - ClO 2 F between 0 deg. and 100 deg. C, by various techniques (micro-sublimation, isopiestic method, IR and UV spectrography, thermogravimetry and X-ray diffraction) shows that intermediate steps are possible before the production of UF 5 . The whole reaction may be schematised by two equations: (1) n UF 4 + ClO 2 F → n UF x + ClO 2 (4 4 + ClO 2 F → UF x + 1/2 Cl 2 + O 2 . The more the temperature rises, the more the second equation becomes experimentally verified. The reaction at 0 deg. C between UF 5 and ClO 2 F may be represented by: UF 5 + ClO 2 F → UF 6 ClO 2 . The reactions: UF 5 + ClO 2 F → UF 6 + ClO 2 , UF 5 + ClO 2 F → UF 6 + 1/2 Cl 2 + O 2 are verified, the first and the second at 25 deg. C., the second from 50 deg. to 150 deg. C. From the results of AGRON it is possible to predict the residual solids before complete volatilization as UF 6 . The IR spectra of ClO 2 F adsorbed on UF 4 and UF x at 60 deg. C have been compared with those of gaseous ClO 2 F and UF 6 adsorbed on UF 4 . (authors) [fr

  4. Missed causative tumors in diagnosing tumor-induced osteomalacia with (18)F-FDG PET/CT: a potential pitfall of standard-field imaging.

    Science.gov (United States)

    Kaneuchi, Yoichi; Hakozaki, Michiyuki; Yamada, Hitoshi; Hasegawa, Osamu; Tajino, Takahiro; Konno, Shinichi

    2016-01-01

    We describe herein two tumor-induced osteomalacia (TIO) cases for whom the causative lesions, located in their popliteal fossa, that were not identified in the standard field of fluorine-18-fluorodeoxyglucose positron emission tomography/computed tomography ((18)F-FDG PET/CT), which usually images only the head, trunk, and proximal parts of the extremities. A 47 years old Japanese man with multiple pathological fractures due to osteomalacia, accompanied by muscle weakness, hypophosphatemia, and an elevation of alkaline phosphatase (ALP) was referred to our hospital. A (18)F-FDG PET/CT scan was performed, but no (18)F-FDG uptake was detected in the standard field of imaging. Magnetic resonance imaging revealed a small subcutaneous tumor (1.9×1.2×0.6cm) of the left posteriomedial knee, displaying uniform enhancement on gadolinium-enhanced T1-weighted fat-suppression imaging. The tumor was resected widely and diagnosed as phosphaturic mesenchymal tumor, mixed connective tissue variant (PMTMCT). The other patient was a 31 years old Japanese woman with multiple pathological fractures, hypophosphatemia and elevated of ALP and was referred to our hospital on suspicion of TIO. Although the causative lesion was not identified in the standard field of (18)F-FDG PET/CT, (18)F-FDG uptake (SUVmax 2.9) was detected on the right knee in the additional whole-body (18)F-FDG PET/CT. Magnetic resonance imaging revealed a soft-tissue tumor (6.4×4.1×2.9cm) in the right posterior knee. Following biopsy, the tumor was marginally resected, and was pathologically diagnosed as PMTMCT. Once patients are suspected to have TIO, a whole-body nuclear imaging study such as (18)F-FDG PET/CT should be performed, in order not to miss the hidden causative tumor, especially occurring in the distal extremities.

  5. The manifestation of 18F-FDG imaging of coincidence SPECT in benign pulmonary diseases

    International Nuclear Information System (INIS)

    Miao Jisheng; Liu Jinjun; Wu Jiyong; Pan Huizhong; Wang Huoqiang; Shen Yi; Shi Degang

    2001-01-01

    Objective: To study the uptake of the 18 F-FDG in the benign pulmonary diseases with dual head SPECT coincidence detection system. Methods: Scanning were performed with dual head SPECT coincidence detection system for patients with pulmonary diseases,the uptake and the imaging characteristic of the diseases were analysed. Results: 1) In 28 tuberculosis (TB) patients, 19 cases with a negative imaging (68%, 19/28), whereas 9 cases with a positive result (32%, 9/28). The T/N value of the TB is 1.7 +- 1.2, but the T/N of the lung cancer is 4.1 +- 2.4, significantly different from them. In the skin PPD test, 9 cases with positive scans showed a 16.2 (12 - 22) mm diameter red spot, but 7 cases of negative scans with a 8.6 (0 - 15) mm diameter, both also have a significant difference. 2) Out of the 8 patients suffered from sarcoidosis, among them 5 active stage with positive scans, whereas another 3 remission cases with negative results. 3) In 18 inflammation cases, positive imagings were showed in 6 patients with cryptococcosis, mycoplasma pneumonia, mycosis, organized pneumonia, lung abscess and bacteria pneumonia. Conclusions: In some benign pulmonary diseases, 18 F-FDG imaging can be positive also. Analysing the characteristic of the imaging could rise specificity in lung cancer and also give some new clues to treatment of these benign pulmonary diseases

  6. {sup 18}F-NaF PET/CT: EANM procedure guidelines for bone imaging

    Energy Technology Data Exchange (ETDEWEB)

    Beheshti, M.; Langsteger, W. [St Vincent' s Hospital, PET - CT Center LINZ, Department of Nuclear Medicine and Endocrinology, Linz (Austria); Mottaghy, F.M. [University Hospital Aachen, RWTH Aachen University, Department of Nuclear Medicine, Aachen (Germany); Maastricht University Medical Center, Department of Nuclear Medicine, Maastricht (Netherlands); Payche, F. [Louis Mourier Hospital, Department of Nuclear Medicine, Colombes (France); Behrendt, F.F.F. [University Hospital Aachen, RWTH Aachen University, Department of Nuclear Medicine, Aachen (Germany); Wyngaert, T.V. den [Antwerp University Hospital, Department of Nuclear Medicine, Edegem (Belgium); Fogelman, I. [King' s College, Department of Nuclear Medicine, London (United Kingdom); Strobel, K. [Lucerne Cantonal Hospital, Department of Radiology and Nuclear Medicine, Lucerne (Switzerland); Celli, M.; Fanti, S. [Policlinico S. Orsola-Malpighi, Department of Nuclear Medicine, PET Unit, Bologna (Italy); Giammarile, F. [Centre Hospitalier Universitaire de Lyon, Department of Nuclear Medicine, Lyon (France); Krause, B. [University Hospital Rostock, Department of Nuclear Medicine, Rostock (Germany)

    2015-10-15

    The aim of this guideline is to provide minimum standards for the performance and interpretation of {sup 18}F-NaF PET/CT scans. Standard acquisition and interpretation of nuclear imaging modalities will help to provide consistent data acquisition and numeric values between different platforms and institutes and to promote the use of PET/CT modality as an established diagnostic modality in routine clinical practice. This will also improve the value of scientific work and its contribution to evidence-based medicine. (orig.)

  7. Azeotrope in LiF-HfF4 system

    International Nuclear Information System (INIS)

    Sorokin, I.D.; Korenev, Yu.M.; Sidorov, L.N.

    1975-01-01

    The gaseous phase of the system LiF-HfF 4 is investigated by means of isothermal evaporation. Using experimental data, p-X diagrams are constructed for 1125, 1075, 1025, 975 and 925 K. It is shown that the azeotrope with minimum total pressure observed at 1125 K degenerates upon lowering of the temperature and entry into the heterogeneous region. At 975 K the azeotrope corresponds to the point of inflexion from the horizontal tangent on the total pressure curve. At lower temperatures azeotropic distillation is absent from the system. (author)

  8. In Vivo 6-([18F]Fluoroacetamido-1-hexanoicanilide PET Imaging of Altered Histone Deacetylase Activity in Chemotherapy-Induced Neurotoxicity

    Directory of Open Access Journals (Sweden)

    Nobuyoshi Fukumitsu

    2018-01-01

    Full Text Available Background. Histone deacetylases (HDACs regulate gene expression by changing histone deacetylation status. Neurotoxicity is one of the major side effects of cisplatin, which reacts with deoxyribonucleic acid (DNA and has excellent antitumor effects. Suberoylanilide hydroxamic acid (SAHA is an HDAC inhibitor with neuroprotective effects against cisplatin-induced neurotoxicity. Purpose. We investigated how cisplatin with and without SAHA pretreatment affects HDAC expression/activity in the brain by using 6-([18F]fluoroacetamido-1-hexanoicanilide ([18F]FAHA as a positron emission tomography (PET imaging agent for HDAC IIa. Materials and Methods. [18F]FAHA and [18F]fluoro-2-deoxy-2-D-glucose ([18F]FDG PET studies were done in 24 mice on 2 consecutive days and again 1 week later. The mice were divided into three groups according to drug administration between the first and second imaging sessions (Group A: cisplatin 2 mg/kg, twice; Group B: cisplatin 4 mg/kg, twice; Group C: cisplatin 4 mg/kg, twice, and SAHA 300 mg/kg pretreatment, 4 times. Results. The Ki value of [18F]FAHA was increased and the percentage of injected dose/tissue g (% ID/g of [18F]FDG was decreased in the brains of animals in Groups A and B. The Ki value of [18F]FAHA and % ID/g of [18F]FDG were not significantly different in Group C. Conclusions. [18F]FAHA PET clearly showed increased HDAC activity suggestive of cisplatin neurotoxicity in vivo, which was blocked by SAHA pretreatment.

  9. Evaluation of 18F-labeled icotinib derivatives as potential PET agents for tumor imaging

    International Nuclear Information System (INIS)

    Hongyu Ren; Hongyu Ning; Jin Chang; Mingxia Zhao; Yong He; Yan Chong; Chuanmin Qi

    2016-01-01

    In this study, three 18 F-labeled crown ether fused anilinoquinazoline derivatives ([ 18 F]11a-c) were synthesized and evaluated as potential tumor imaging probes. The biodistribution results of [ 18 F]11b were good. Compared with [ 18 F]-fludeoxyglucose and l-[ 18 F]-fluoroethyltyrosine in the same animal model, [ 18 F]11b had better tumor/brain, tumor/muscle, and tumor/blood uptake ratios. Overall, these results suggest that [ 18 F]11b is promising as a tumor imaging agent for positron emission tomography. (author)

  10. Anesthesia condition for 18F-FDG imaging of lung metastasis tumors using small animal PET

    International Nuclear Information System (INIS)

    Woo, Sang-Keun; Lee, Tae Sup; Kim, Kyeong Min; Kim, June-Youp; Jung, Jae Ho; Kang, Joo Hyun; Cheon, Gi Jeong; Choi, Chang Woon; Lim, Sang Moo

    2008-01-01

    Small animal positron emission tomography (PET) with 18 F-FDG has been increasingly used for tumor imaging in the murine model. The aim of this study was to establish the anesthesia condition for imaging of lung metastasis tumor using small animal 18 F-FDG PET. Methods: To determine the impact of anesthesia on 18 F-FDG distribution in normal mice, five groups were studied under the following conditions: no anesthesia, ketamine and xylazine (Ke/Xy), 0.5% isoflurane (Iso 0.5), 1% isoflurane (Iso 1) and 2% isoflurane (Iso 2). The ex vivo counting, standard uptake value (SUV) image and glucose SUV of 18 F-FDG in various tissues were evaluated. The 18 F-FDG images in the lung metastasis tumor model were obtained under no anesthesia, Ke/Xy and Iso 0.5, and registered with CT image to clarify the tumor region. Results: Blood glucose concentration and muscle uptake of 18 F-FDG in the Ke/Xy group markedly increased more than in the other groups. The Iso 2 group increased 18 F-FDG uptake in heart compared with the other groups. The Iso 0.5 anesthesized group showed the lowest 18 F-FDG uptake in heart and chest wall. The small size of lung metastasis tumor (2 mm) was clearly visualized by 18 F-FDG image with the Iso 0.5 anesthesia. Conclusion: Small animal 18 F-FDG PET imaging with Iso 0.5 anesthesia was appropriate for the detection of lung metastasis tumor. To acquire 18 F-FDG PET images with small animal PET, the type and level of anesthetic should be carefully considered to be suitable for the visualization of target tissue in the experimental model

  11. Biodistribution, toxicity and radiation dosimetry studies of the serotonin transporter radioligand 4-[{sup 18}F]-ADAM in rats and monkeys

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Ya-Yao [Tri-Service General Hospital, PET Center, Department of Nuclear Medicine, Taipei (China); National Tsing Hua University, Department of Biomedical Engineering and Environmental Sciences, Hsinchu (China); Ma, Kuo-Hsing [National Defense Medical Center, Department of Biology and Anatomy, Taipei (China); Tseng, Ta-Wei; Chou, Ta-Kai; Huang, Wen-Sheng [Tri-Service General Hospital, PET Center, Department of Nuclear Medicine, Taipei (China); Ng, Hanna; Mirsalis, Jon C. [SRI International, Menlo Park, CA (United States); Fu, Ying-Kai [Institute of Nuclear Energy Research, Taoyuan (China); Chung Yuan Christian University, Department of Chemistry, Chung-Li (China); Chu, Tieh-Chi [National Tsing Hua University, Department of Biomedical Engineering and Environmental Sciences, Hsinchu (China); Yuanpei University, Department of Radiological Technology, Hsinchu (China); Shiue, Chyng-Yann [Tri-Service General Hospital, PET Center, Department of Nuclear Medicine, Taipei (China); University of Pennsylvania, Department of Radiology, Philadelphia, PA (United States)

    2010-03-15

    4-[{sup 18}F]-ADAM is a potent serotonin transport imaging agent. We studied its toxicity in rats and radiation dosimetry in monkeys before human studies are undertaken. Single and multiple-dosage toxicity studies were conducted in Sprague-Dawley rats. Male and female rats were injected intravenously with 4-F-ADAM as a single dose of 1,023.7 {mu}g/kg (1,000 times the human dose) or as five consecutive daily doses of 102.37 {mu}g/kg (100 times the human dose). PET/CT scans were performed in seven Formosa Rock monkeys (four males and three females) using a Siemens Biograph scanner. After injection of 4-[{sup 18}F]-ADAM (182{+-}8 MBq), a low dose CT scan and a series of eight whole-body PET scans were performed. Whole-body images were acquired in 3-D mode. Time-activity data of source organs were used to calculate the residence times and estimate the absorbed radiation dose using OLINDA/EXM software. In the rats neither the single dose nor the five daily doses of 4-F-ADAM produced overt adverse effects clinically. In the monkeys the radiation doses received by most organs ranged between 7.1 and 35.7 {mu}Gy/MBq, and the urinary bladder was considered to be the critical organ. The effective doses extrapolated to male and female adult humans were 17.4 and 21.8 {mu}Sv/MBq, respectively. Toxicity studies in Sprague-Dawley rats and radiation dosimetry studies in Formosa Rock monkeys suggested that 4-[{sup 18}F]-ADAM is safe for use in human PET imaging studies. (orig.)

  12. Both flagella and F4 fimbriae from F4ac+ enterotoxigenic Escherichia coli contribute to attachment to IPEC-J2 cells in vitro.

    Science.gov (United States)

    Zhou, Mingxu; Duan, Qiangde; Zhu, Xiaofang; Guo, Zhiyan; Li, Yinchau; Hardwidge, Philip R; Zhu, Guoqiang

    2013-05-13

    The role of flagella in the pathogenesis of F4ac+ Enterotoxigenic Escherichia coli (ETEC) mediated neonatal and post-weaning diarrhea (PWD) is not currently understood. We targeted the reference C83902 ETEC strain (O8:H19:F4ac+ LT+ STa+ STb+), to construct isogenic mutants in the fliC (encoding the major flagellin protein), motA (encoding the flagella motor), and faeG (encoding the major subunit of F4 fimbriae) genes. Both the ΔfliC and ΔfaeG mutants had a reduced ability to adhere to porcine intestinal epithelial IPEC-J2 cells. F4 fimbriae expression was significantly down-regulated after deleting fliC, which revealed that co-regulation exists between flagella and F4 fimbriae. However, there was no difference in adhesion between the ΔmotA mutant and its parent strain. These data demonstrate that both flagella and F4 fimbriae are required for efficient F4ac+ ETEC adhesion in vitro.

  13. Usefulness of [18F]-DA and [18F]-DOPA for PET imaging in a mouse model of pheochromocytoma

    International Nuclear Information System (INIS)

    Martiniova, Lucia; Cleary, Susannah; Lai, Edwin W.; Kiesewetter, Dale O.; Seidel, Jurgen; Dawson, Linda F.; Phillips, Jacqueline K.; Thomasson, David; Chen Xiaoyuan; Eisenhofer, Graeme; Powers, James F.; Kvetnansky, Richard

    2012-01-01

    Purpose: To evaluate the usefulness of [ 18 F]-6-fluorodopamine ([ 18 F]-DA) and [ 18 F]-L-6-fluoro-3,4-dihydroxyphenylalanine ([ 18 F]-DOPA) positron emission tomography (PET) in the detection of subcutaneous (s.c.) and metastatic pheochromocytoma in mice; to assess the expression of the norepinephrine transporter (NET) and vesicular monoamine transporters 1 and 2 (VMAT1 and VMAT2), all important for [ 18 F]-DA and [ 18 F]-DOPA uptake. Furthermore, to compare tumor detection by micro-computed tomography (microCT) to magnetic resonance imaging (MRI) in individual mouse. Methods: SUV max values were calculated from [ 18 F]-DA and [ 18 F]-DOPA PET, tumor-to-liver ratios (TLR) were obtained and expression of NET, VMAT1 and VMAT2 was evaluated. Results: [ 18 F]-DA detected less metastatic lesions compared to [ 18 F]-DOPA. TLR values for liver metastases were 2.26–2.71 for [ 18 F]-DOPA and 1.83–2.83 for [ 18 F]-DA. A limited uptake of [ 18 F]-DA was found in s.c. tumors (TLR=0.22-0.27) compared to [ 18 F]-DOPA (TLR=1.56-2.24). Overall, NET and VMAT2 were expressed in all organ and s.c. tumors. However, s.c. tumors lacked expression of VMAT1. We confirmed [ 18 F]-DA's high affinity for the NET for its uptake and VMAT1 and VMAT2 for its storage and retention in pheochromocytoma cell vesicles. In contrast, [ 18 F]-DOPA was found to utilize only VMAT2. Conclusion: MRI was superior in the detection of all organ tumors compared to microCT and PET. [ 18 F]-DOPA had overall better sensitivity than [ 18 F]-DA for the detection of metastases. Subcutaneous tumors were localized only with [ 18 F]-DOPA, a finding that may reflect differences in expression of VMAT1 and VMAT2, perhaps similar to some patients with pheochromocytoma where [ 18 F]-DOPA provides better visualization of lesions than [ 18 F]-DA.

  14. Imaging findings and literature review of 18F-FDG PET/CT in primary systemic AL amyloidosis

    International Nuclear Information System (INIS)

    Lee, Joo Hee; Lee, Ga Yeon; Kim, Seok Jin; Kim, Ki Hyun; Jeon, Eun Seok; Lee, Kyung Han; Kim, Byung Tae; Choi, Joon Young

    2015-01-01

    Although several case reports and case series have described 18 F-FDG PET/CT in amyloidosis, the value of 18 F-FDG PET/CT for diagnosing amyloidosis has not been clarified. We investigated the imaging findings of 18 F-FDG PET/CT in patients with primary systemic AL amyloidosis. Subjects were 15 patients (M:F = 12:3; age, 61.5 ± 7.4 years) with histologically confirmed primary systemic AL amyloidosis who underwent pretreatment 18 F-FDG PET/CT to rule out the possibility of malignancy or for initial workup of alleged cancer. For involved organs, visual and semiquantitative analyses were performed on 18 F-FDG PET/CT images. In total, 22 organs (10 hearts, 5 kidneys, 2 stomachs, 2 colons, 1 ileum, 1 pancreas, and 1 liver) were histologically confirmed to have primary systemic AL amyloidosis. F-FDG uptake was significantly increased in 15 of the 22 organs (68.2 %; 10 hearts, 2 kidneys, 1 colon, 1 ileum, and 1 liver; SUV max  = 7.0 ± 3.2, range 2.1–14.1). However, in 11 of 15 PET-positive organs (78.6 %; 10 hearts and the ileum), it was difficult to differentiate pathological uptake from physiological uptake. Definitely abnormal 18 F-FDG uptake was found in only 4 of the 22 organs (18.2 %; 2 kidneys, 1 colon, and the liver). 18 F-FDG uptake was negative for pancreas and gastric lesions. Although 18 F-FDG PET/CT showed high uptake in two-thirds of the organs involving primary systemic AL amyloidosis, its sensitivity appeared to be low to make differentiation of pathological uptake from physiological uptake. However, due to the small number of cases, further study for the role of 18 F-FDG PET/CT in amyloidosis will be warranted

  15. DPP-4 inhibitor des-F-sitagliptin treatment increased insulin exocytosis from db/db mice {beta} cells

    Energy Technology Data Exchange (ETDEWEB)

    Nagamatsu, Shinya, E-mail: shinya@ks.kyorin-u.ac.jp [Department of Biochemistry, Kyorin University School of Medicine, Mitaka, Tokyo 181-8611 (Japan); Ohara-Imaizumi, Mica; Nakamichi, Yoko; Aoyagi, Kyota; Nishiwaki, Chiyono [Department of Biochemistry, Kyorin University School of Medicine, Mitaka, Tokyo 181-8611 (Japan)

    2011-09-09

    Highlights: {yields} Anti-diabetic new drug, DPP-4 inhibitor, can affect the insulin exocytosis. {yields} DPP-4 inhibitor treatment altered syntaxin 1 expression. {yields} Treatment of db/db mice with DPP-4 inhibitor increased insulin release. -- Abstract: Incretin promotes insulin secretion acutely. Recently, orally-administered DPP-4 inhibitors represent a new class of anti-hyperglycemic agents. Indeed, inhibitors of dipeptidyl peptidase-IV (DPP-4), sitagliptin, has just begun to be widely used as therapeutics for type 2 diabetes. However, the effects of sitagliptin-treatment on insulin exocytosis from single {beta}-cells are yet unknown. We therefore investigated how sitagliptin-treatment in db/db mice affects insulin exocytosis by treating db/db mice with des-F-sitagliptin for 2 weeks. Perfusion studies showed that 2 weeks-sitagliptin treatment potentiated insulin secretion. We then analyzed insulin granule motion and SNARE protein, syntaxin 1, by TIRF imaging system. TIRF imaging of insulin exocytosis showed the increased number of docked insulin granules and increased fusion events from them during first-phase release. In accord with insulin exocytosis data, des-F-sitagliptin-treatment increased the number of syntaxin 1 clusters on the plasma membrane. Thus, our data demonstrated that 2-weeks des-F-sitagliptin-treatment increased the fusion events of insulin granules, probably via increased number of docked insulin granules and that of syntaxin 1 clusters.

  16. P-T and T-x projections of phase diagram of CsF-ZrF4 system

    International Nuclear Information System (INIS)

    Karasev, N.M.; Korenev, Yu.M.; Sidorov, L.N.

    1980-01-01

    The CsF-ZrF 4 system has been investigated by the Knudsen effusion method and mass-spectral analysis of vaporization products. A molecular composition of vapour was determined. CsF, Cs 2 F 2 , ZrF 4 , Cs 2 ZrF 6 , CsZrF 5 , CsZr 2 F 9 molecules were found in the saturated vapour of the system. Heats of phase transitions and partial pressures of the molecules detected were determined depending on the melt compositions. Dissociation enthalpies of complex molecules were calculated. P-T and T-x projections of the state diagram of the CsF-ZrF 4 system were constructed

  17. What does See the Impulse Acoustic Microscopy inside Nanocomposites?

    Science.gov (United States)

    Levin, V. M.; Petronyuk, Y. S.; Morokov, E. S.; Celzard, A.; Bellucci, S.; Kuzhir, P. P.

    The paper presents results of studying bulk microstructure in carbon nanocomposites by impulse acoustic microscopy technique. Nanocomposite materials are in the focus of interest because of their outstanding properties in minimal nanofiller content. Large surface area and high superficial activity cause strong interaction between nanoparticles that can result in formation of fractal conglomerates. This paper involves results of the first direct observation of nanoparticle conglomerates inside the bulk of epoxy-carbon nanocomposites. Diverse types of carbon nanofiller have been under investigation. The impulse acoustic microscope SIAM-1 (Acoustic Microscopy Lab, IBCP RAS) has been employed for 3D imaging bulk microstructure and measuring elastic properties of the nanocomposite specimens. The range of 50-200 MHz allows observing microstructure inside the entire specimen bulk. Acoustic images are obtained in the ultramicroscopic regime; they are formed by the Rayleigh type scattered radiation. It has been found the high-resolution acoustic vision (impulse acoustic microscopy) is an efficient technique to observe mesostructure formed by fractal cluster inside nanocomposites. The clusterization takes its utmost form in nanocomposites with graphite nanoplatelets as nanofiller. The nanoparticles agglomerate into micron-sized conglomerates distributed randomly over the material. Mesostructure in nanocomposites filled with carbon nanotubes is alternation of regions with diverse density of nanotube packing. Regions with alternative density of CNT packing are clearly seen in acoustical images as neighboring pixels of various brightness.

  18. Longitudinal imaging of Alzheimer pathology using [{sup 11}C]PIB, [{sup 18}F]FDDNP and [{sup 18}F]FDG PET

    Energy Technology Data Exchange (ETDEWEB)

    Ossenkoppele, Rik; Tolboom, Nelleke; Adriaanse, Sofie F. [VU University Medical Center, Department of Neurology and Alzheimer Center, PO Box 7057, Amsterdam (Netherlands); VU University Medical Center, Department of Nuclear Medicine and PET Research, Amsterdam (Netherlands); Foster-Dingley, Jessica C.; Boellaard, Ronald; Yaqub, Maqsood; Windhorst, Albert D.; Lammertsma, Adriaan A.; Berckel, Bart N.M. van [VU University Medical Center, Department of Nuclear Medicine and PET Research, Amsterdam (Netherlands); Barkhof, Frederik [VU University Medical Center, Department of Radiology, Amsterdam (Netherlands); Scheltens, Philip [VU University Medical Center, Department of Neurology and Alzheimer Center, PO Box 7057, Amsterdam (Netherlands); Flier, Wiesje M. van der [VU University Medical Center, Department of Neurology and Alzheimer Center, PO Box 7057, Amsterdam (Netherlands); VU University Medical Center, Department of Epidemiology and Biostatistics, Amsterdam (Netherlands)

    2012-06-15

    [{sup 11}C]PIB and [{sup 18}F]FDDNP are PET tracers for in vivo detection of the neuropathology underlying Alzheimer's disease (AD). [{sup 18}F]FDG is a glucose analogue and its uptake reflects metabolic activity. The purpose of this study was to examine longitudinal changes in these tracers in patients with AD or mild cognitive impairment (MCI) and in healthy controls. Longitudinal, paired, dynamic [{sup 11}C]PIB and [{sup 18}F]FDDNP (90 min each) and static [{sup 18}F]FDG (15 min) PET scans were obtained in 11 controls, 12 MCI patients and 8 AD patients. The mean interval between baseline and follow-up was 2.5 years (range 2.0-4.0 years). Parametric [{sup 11}C]PIB and [{sup 18}F]FDDNP images of binding potential (BP{sub ND}) and [{sup 18}F]FDG standardized uptake value ratio (SUVr) images were generated. A significant increase in global cortical [{sup 11}C]PIB BP{sub ND} was found in MCI patients, but no changes were observed in AD patients or controls. Subsequent regional analysis revealed that this increase in [{sup 11}C]PIB BP{sub ND} in MCI patients was most prominent in the lateral temporal lobe (p < 0.05). For [{sup 18}F]FDDNP, no changes in global BP{sub ND} were found. [{sup 18}F]FDG uptake was reduced at follow-up in the AD group only, especially in frontal, parietal and lateral temporal lobes (all p < 0.01). Changes in global [{sup 11}C]PIB binding ({rho} = -0.42, p < 0.05) and posterior cingulate [{sup 18}F]FDG uptake ({rho} = 0.54, p < 0.01) were correlated with changes in Mini-Mental-State Examination score over time across groups, whilst changes in [{sup 18}F]FDDNP binding ({rho} = -0.18, p = 0.35) were not. [{sup 11}C]PIB and [{sup 18}F]FDG track molecular changes in different stages of AD. We found increased amyloid load in MCI patients and progressive metabolic impairment in AD patients. [{sup 18}F]FDDNP seems to be less useful for examining disease progression. (orig.)

  19. Magnetoactive Acoustic Metamaterials.

    Science.gov (United States)

    Yu, Kunhao; Fang, Nicholas X; Huang, Guoliang; Wang, Qiming

    2018-04-11

    Acoustic metamaterials with negative constitutive parameters (modulus and/or mass density) have shown great potential in diverse applications ranging from sonic cloaking, abnormal refraction and superlensing, to noise canceling. In conventional acoustic metamaterials, the negative constitutive parameters are engineered via tailored structures with fixed geometries; therefore, the relationships between constitutive parameters and acoustic frequencies are typically fixed to form a 2D phase space once the structures are fabricated. Here, by means of a model system of magnetoactive lattice structures, stimuli-responsive acoustic metamaterials are demonstrated to be able to extend the 2D phase space to 3D through rapidly and repeatedly switching signs of constitutive parameters with remote magnetic fields. It is shown for the first time that effective modulus can be reversibly switched between positive and negative within controlled frequency regimes through lattice buckling modulated by theoretically predicted magnetic fields. The magnetically triggered negative-modulus and cavity-induced negative density are integrated to achieve flexible switching between single-negative and double-negative. This strategy opens promising avenues for remote, rapid, and reversible modulation of acoustic transportation, refraction, imaging, and focusing in subwavelength regimes. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. Neurofunctional imaging of the pancreas utilizing the cholinergic PET radioligand [18F]4-fluorobenzyltrozamicol

    International Nuclear Information System (INIS)

    Clark, P.B.; Gage, H.D.; Brown-Proctor, C.; Buchheimer, N.; Morton, K.A.; Calles-Escandon, J.; Mach, R.H.

    2004-01-01

    The pancreas is one of the most heavily innervated peripheral organs in the body. Parasympathetic and sympathetic neurons terminate in the pancreas and provide tight control of endocrine and exocrine functions. The aim of this study was to determine whether the pancreas can be imaged with a radioligand that binds to specific neuroreceptors. Using fluorine-18 4-fluorobenzyltrozamicol (FBT), which binds to the presynaptic vesicular acetylcholine transporter, positron emission tomography scans were performed in four adult mice, two adult rhesus monkeys, and one adult human. In these mammals, the pancreas is intensely FBT avid, with uptake greater than in any other organ at 30, 60, and 90 min. The maximum standardized uptake value (SUV) ratios of pancreas to liver, for example, ranged from 1.4 to 1.7 in rhesus monkeys (mean 1.6; median 1.7) and from 1.9 to 4.7 (mean 3.24; median 3.02) in mice. The maximum SUV ratio of pancreas to liver in the human was 1.8. These data suggest that neuroreceptor imaging of the pancreas in vivo is feasible in animal models and humans. This imaging could allow researchers to interrogate functions under control of the autonomic nervous system in the pancreas, with applications possible in transplanted and native pancreata. Also, as beta cell function is intimately related to parasympathetic cholinergic input, FBT activity in the pancreas may correlate with insulin-producing beta cell mass. This could ultimately provide a method of in vivo imaging in animal models and humans for diabetes research. (orig.)

  1. Synthesis and evaluation of 4-[F-18]fluoro thalidomide for the in vivo studies of angiogenesis

    International Nuclear Information System (INIS)

    Kim, D. H.; Choi, Y. S.; Jeong, K. H.; Lee, K. H.; Choi, Y.; Kim, B. T.

    2005-01-01

    Thalidomide has been recently rediscovered for its possible utility as an antitumor agent, although it was marketed as a sedative in the 1950s and later found to be a potent teratogen. In this study, therefore, F-18 labeled thalidomide was synthesized and evaluated for the in vivo studies of angiogenesis. 4-[F-18]Fluoro thalidomide ([F-18]1) was prepared by labeling of 4-trimethylammonium thalidomide triflate with TBA[F-18]F in DMSO (90 .deg. C, 10 min) and purified by HPLC. The triflate salt was prepared from 3-fluoro phthalic anhydride in 3 steps. [F-18]1 was incubated with HUVEC cells at 37 .deg. C for 15, 30, 60, and 120 min, respectively. Dynamic PET images of [F-18]1 was obtained in mice implanted with LLC cells. In vitro metabolism study of [F-18]1 was carried out using mouse, rabbit, or human liver microsomes in the presence of NADPH, and the metabolites obtained from the mouse liver microsomal incubation of 1 were analyzed using LC-MS. Radiochemical yield of [F-18]1 was 50-60%, and the specific activity was 42-120 GBq/imol. The HUVEC cell uptake of [F-18]1 increased with time (100% at 15 min and 241% at 120 min). PET images showed that the radioactivity was accumulated in the liver, the kidneys and the bladder of the mice, and brain uptake was shown from 40 min postinjection. However, there was low level of radioactivity uptake in tumor. [F-18]1 was not metabolized by mouse, rabbit, or human liver microsomes but was hydrolyzed significantly at physiological pH. The hydrolyzed product was further analyzed by LC-MS, showing a mass peak corresponding to that of 4-fluoro-N-(o-carboxybenzoyl)glutamic acid imide. This result suggests that [F-18]1 is easily hydrolyzed at physiological pH and thus may not be suitable for the in vivo studies of tumor angiogenesis at least in rodents, although it was reported that the hydrolysis product of thalidomide may be responsible for its angiogenesis activity in humans

  2. The use of Acoustic Radiation Force decorrelation-weighted pulse inversion (ADW-PI) for enhanced ultrasound contrast imaging

    Science.gov (United States)

    Herbst, Elizabeth; Unnikrishnan, Sunil; Wang, Shiying; Klibanov, Alexander L.; Hossack, John A.; Mauldin, F. William

    2016-01-01

    Objectives The use of ultrasound imaging for cancer diagnosis and screening can be enhanced with the use of molecularly targeted microbubbles. Nonlinear imaging strategies such as pulse inversion (PI) and “contrast pulse sequences” (CPS) can be used to differentiate microbubble signal, but often fail to suppress highly echogenic tissue interfaces. This failure results in false positive detection and potential misdiagnosis. In this study, a novel Acoustic Radiation Force (ARF) based approach was developed for superior microbubble signal detection. The feasibility of this technique, termed ARF-decorrelation-weighted PI (ADW-PI), was demonstrated in vivo using a subcutaneous mouse tumor model. Materials and Methods Tumors were implanted in the hindlimb of C57BL/6 mice by subcutaneous injection of MC38 cells. Lipid-shelled microbubbles were conjugated to anti-VEGFR2 antibody and administered via bolus injection. An image sequence using ARF pulses to generate microbubble motion was combined with PI imaging on a Verasonics Vantage programmable scanner. ADW-PI images were generated by combining PI images with inter-frame signal decorrelation data. For comparison, CPS images of the same mouse tumor were acquired using a Siemens Sequoia clinical scanner. Results Microbubble-bound regions in the tumor interior exhibited significantly higher signal decorrelation than static tissue (n = 9, p < 0.001). The application of ARF significantly increased microbubble signal decorrelation (n = 9, p < 0.01). Using these decorrelation measurements, ADW-PI imaging demonstrated significantly improved microbubble contrast-to-tissue ratio (CTR) when compared to corresponding CPS or PI images (n = 9, p < 0.001). CTR improved with ADW-PI by approximately 3 dB compared to PI images and 2 dB compared to CPS images. Conclusions Acoustic radiation force can be used to generate adherent microbubble signal decorrelation without microbubble bursting. When combined with pulse inversion

  3. High-speed photoacoustic imaging using an LED-based photoacoustic imaging system

    Science.gov (United States)

    Sato, Naoto; Kuniyil Ajith Singh, Mithun; Shigeta, Yusuke; Hanaoka, Takamitsu; Agano, Toshitaka

    2018-02-01

    Recently we developed a multispectral LED-based photoacoustic/ultrasound imaging system (AcousticX) and have been continuously working on its technical/functional improvements. AcousticX is a linear array ultrasound transducer (128 elements, 10 MHz)-based system in which LED arrays (selectable wavelengths, pulse repetition frequency: 4 kHz, pulse width: tunable from 40 - 100 ns) are fixed on both sides of the transducer to illuminate the tissue for photoacoustic imaging. The ultrasound/photoacoustic data from all 128 elements can be simultaneously acquired, processed and displayed. We already demonstrated our system's capability to perform photoacoustic/ultrasound imaging for dynamic imaging of the tissue at a frame rate of 10 Hz (for example to visualize the pulsation of arteries in vivo in human subjects). In this work, we present the development of a new high-speed imaging mode in AcousticX. In this mode, instead of toggling between ultrasound and photoacoustic measurements, it is possible to continuously acquire only photoacoustic data for 1.5 seconds with a time interval of 1 ms. With this improvement, we can record photoacoustic signals from the whole aperture (38 mm) at fast rate and can be reviewed later at different speeds for analyzing dynamic changes in the photoacoustic signals. We believe that AcousticX with this new high-speed mode opens up a feasible technical path for multiple dynamic studies, for example one which focus on imaging the response of voltage sensitive dyes. We envisage to improve the acquisition speed further in future for exploring ultra-high-speed applications.

  4. Volumetric BOLD fMRI simulation: from neurovascular coupling to multivoxel imaging

    International Nuclear Information System (INIS)

    Chen, Zikuan; Calhoun, Vince

    2012-01-01

    The blood oxygenation-level dependent (BOLD) functional magnetic resonance imaging (fMRI) modality has been numerically simulated by calculating single voxel signals. However, the observation on single voxel signals cannot provide information regarding the spatial distribution of the signals. Specifically, a single BOLD voxel signal simulation cannot answer the fundamental question: is the magnetic resonance (MR) image a replica of its underling magnetic susceptibility source? In this paper, we address this problem by proposing a multivoxel volumetric BOLD fMRI simulation model and a susceptibility expression formula for linear neurovascular coupling process, that allow us to examine the BOLD fMRI procedure from neurovascular coupling to MR image formation. Since MRI technology only senses the magnetism property, we represent a linear neurovascular-coupled BOLD state by a magnetic susceptibility expression formula, which accounts for the parameters of cortical vasculature, intravascular blood oxygenation level, and local neuroactivity. Upon the susceptibility expression of a BOLD state, we carry out volumetric BOLD fMRI simulation by calculating the fieldmap (established by susceptibility magnetization) and the complex multivoxel MR image (by intravoxel dephasing). Given the predefined susceptibility source and the calculated complex MR image, we compare the MR magnitude (phase, respectively) image with the predefined susceptibility source (the calculated fieldmap) by spatial correlation. The spatial correlation between the MR magnitude image and the magnetic susceptibility source is about 0.90 for the settings of T E = 30 ms, B 0 = 3 T, voxel size = 100 micron, vessel radius = 3 micron, and blood volume fraction = 2%. Using these parameters value, the spatial correlation between the MR phase image and the susceptibility-induced fieldmap is close to 1.00. Our simulation results show that the MR magnitude image is not an exact replica of the magnetic susceptibility

  5. How restful is it with all that noise? Comparison of Interleaved silent steady state (ISSS) and conventional imaging in resting-state fMRI.

    Science.gov (United States)

    Andoh, J; Ferreira, M; Leppert, I R; Matsushita, R; Pike, B; Zatorre, R J

    2017-02-15

    Resting-state fMRI studies have become very important in cognitive neuroscience because they are able to identify BOLD fluctuations in brain circuits involved in motor, cognitive, or perceptual processes without the use of an explicit task. Such approaches have been fruitful when applied to various disordered populations, or to children or the elderly. However, insufficient attention has been paid to the consequences of the loud acoustic scanner noise associated with conventional fMRI acquisition, which could be an important confounding factor affecting auditory and/or cognitive networks in resting-state fMRI. Several approaches have been developed to mitigate the effects of acoustic noise on fMRI signals, including sparse sampling protocols and interleaved silent steady state (ISSS) acquisition methods, the latter being used only for task-based fMRI. Here, we developed an ISSS protocol for resting-state fMRI (rs-ISSS) consisting of rapid acquisition of a set of echo planar imaging volumes following each silent period, during which the steady state longitudinal magnetization was maintained with a train of relatively silent slice-selective excitation pulses. We evaluated the test-retest reliability of intensity and spatial extent of connectivity networks of fMRI BOLD signal across three different days for rs-ISSS and compared it with a standard resting-state fMRI (rs-STD). We also compared the strength and distribution of connectivity networks between rs-ISSS and rs-STD. We found that both rs-ISSS and rs-STD showed high reproducibility of fMRI signal across days. In addition, rs-ISSS showed a more robust pattern of functional connectivity within the somatosensory and motor networks, as well as an auditory network compared with rs-STD. An increased connectivity between the default mode network and the language network and with the anterior cingulate cortex (ACC) network was also found for rs-ISSS compared with rs-STD. Finally, region of interest analysis showed

  6. Imaging sciences workshop

    Energy Technology Data Exchange (ETDEWEB)

    Candy, J.V.

    1994-11-15

    This workshop on the Imaging Sciences sponsored by Lawrence Livermore National Laboratory contains short abstracts/articles submitted by speakers. The topic areas covered include the following: Astronomical Imaging; biomedical imaging; vision/image display; imaging hardware; imaging software; Acoustic/oceanic imaging; microwave/acoustic imaging; computed tomography; physical imaging; imaging algorithms. Selected papers are indexed separately for inclusion in the Energy Science and Technology Database.

  7. The F4 fimbrial antigen of Escherichia coli and its receptors.

    NARCIS (Netherlands)

    Van den Broeck, W; Cox, E; Oudega, B.; Goddeeris, B

    2000-01-01

    F4 or K88 fimbriae are long filamentous polymeric surface proteins of enterotoxigenic Escherichia coli (ETEC), consisting of so-called major (FaeG) and minor (FaeF, FaeH, FaeC, and probably FaeI) subunits. Several serotypes of F4 have been described, namely F4ab, F4ac, and F4ad. The F4 fimbriae

  8. Phase transitions in (NH4)2MoO2F4 crystal

    Science.gov (United States)

    Krylov, Alexander; Laptash, Natalia; Vtyurin, Alexander; Krylova, Svetlana

    2016-11-01

    The mechanisms of temperature and high pressure phase transitions have been studied by Raman spectroscopy. Room temperature (295 K) experiments under high hydrostatic pressure up to 3.6 GPa for (NH4)2 MoO2 F4 have been carried out. Experimental data indicates a phase transition into a new high-pressure phase for (NH4)2 MoO2 F4 at 1.2 GPa. This phase transition is related to the ordering anion octahedron groups [MoO2 F4]2- and is not associated with ammonium group. Raman spectra of small non-oriented crystals ranging from 10 to 350 K have been observed. The experiment shows anion groups [MoO2 F4]2- and ammonium in high temperature phase are disordered. The phase transition at T1 = 269.8 K is of the first-order, close to the tricritical point. The first temperature phase transition is related to the ordering anion octahedron groups [MoO2 F4]2-. Second phase transitions T2 = 180 K are associated with the ordering of ammonium. The data presented within this study demonstrate that 2D correlation analysis combined with traditional Raman spectroscopy are powerful tool to study phase transitions in the crystals.

  9. Imaging for metabotropic glutamate receptor subtype 1 in rat and monkey brains using PET with [18F]FITM.

    Science.gov (United States)

    Yamasaki, Tomoteru; Fujinaga, Masayuki; Maeda, Jun; Kawamura, Kazunori; Yui, Joji; Hatori, Akiko; Yoshida, Yuichiro; Nagai, Yuji; Tokunaga, Masaki; Higuchi, Makoto; Suhara, Tetsuya; Fukumura, Toshimitsu; Zhang, Ming-Rong

    2012-04-01

    In this study, we evaluate the utility of 4-[(18)F]fluoro-N-[4-[6-(isopropylamino)pyrimidin-4-yl]-1,3-thiazol-2-yl]-N-methylbenzamide ([(18)F]FITM) as a positron emission tomography (PET) ligand for imaging of the metabotropic glutamate receptor subtype 1 (mGluR1) in rat and monkey brains. In vivo distribution of [(18)F]FITM in brains was evaluated by PET scans with or without the mGluR1-selective antagonist (JNJ16259685). Kinetic parameters of monkey PET data were obtained using the two-tissue compartment model with arterial blood sampling. In PET studies in rat and monkey brains, the highest uptake of radioactivity was in the cerebellum, followed by moderate uptake in the thalamus, hippocampus and striatum. The lowest uptake of radioactivity was detected in the pons. These uptakes in all brain regions were dramatically decreased by pre-administration of JNJ16259685. In kinetic analysis of monkey PET, the highest volume of distribution (V(T)) was detected in the cerebellum (V(T) = 11.5). [(18)F]FITM has an excellent profile as a PET ligand for mGluR1 imaging. PET with [(18)F]FITM may prove useful for determining the regional distribution and density of mGluR1 and the mGluR1 occupancy of drugs in human brains.

  10. Interaction of (NH4)2ZrF6 and (NH4)3ZrF7 with strontium and lead nitrates

    International Nuclear Information System (INIS)

    Krysenko, G.F.; Mel'nichenko, E.I.; Ehpov, D.G.; Polishchuk, S.A.

    1991-01-01

    Methods of chemical, X-ray phase, thermogravimetric analysis and IR spectroscopy were used to study reactions between ammonium fluorozirconates and strontium and lead nitrates. Formation of anhydrous hexa- and octafluorozirconates of strontium and lead in the form of MZrF 6 ·0.5NH 4 F and M 2 ZrF 8 ·0.5NH 4 F double salts, which decompose at 315-430 deg C to corresponding hexa- and octafluorozirconates, was established. Effect of hydrofluoric acid on composition of lead fluorozirconates was studied

  11. Acoustic signal analysis in the creeping discharge

    International Nuclear Information System (INIS)

    Nakamiya, T; Sonoda, Y; Tsuda, R; Ebihara, K; Ikegami, T

    2008-01-01

    We have previously succeeded in measuring the acoustic signal due to the dielectric barrier discharge and discriminating the dominant frequency components of the acoustic signal. The dominant frequency components appear over 20kHz of acoustic signal by the dielectric barrier discharge. Recently surface discharge control technology has been focused from practical applications such as ozonizer, NO X reactors, light source or display. The fundamental experiments are carried to examine the creeping discharge using the acoustic signal. When the high voltage (6kV, f = 10kHz) is applied to the electrode, the discharge current flows and the acoustic sound is generated. The current, voltage waveforms of creeping discharge and the sound signal detected by the condenser microphone are stored in the digital memory scope. In this scheme, Continuous Wavelet Transform (CWT) is applied to discriminate the acoustic sound of the micro discharge and the dominant frequency components are studied. CWT results of sound signal show the frequency spectrum of wideband up to 100kHz. In addition, the energy distributions of acoustic signal are examined by CWT

  12. Can multimodality imaging using {sup 18}F-FDG/{sup 18}F-FLT PET/CT benefit the diagnosis and management of patients with pulmonary lesions?

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Baixuan; Guan, Zhiwei; Liu, Changbin; Wang, Ruimin; Yin, Dayi; Zhang, Jinming; Chen, Yingmao; Yao, Shulin; Shao, Mingzhe; Wang, Hui; Tian, Jiahe [Chinese PLA General Hospital, Department of Nuclear Medicine, Beijing (China)

    2011-02-15

    Dual-tracer, {sup 18}F-fluorodeoxyglucose and {sup 18}F-fluorodeoxythymidine ({sup 18}F-FDG/{sup 18}F-FLT), dual-modality (positron emission tomography and computed tomography, PET/CT) imaging was used in a clinical trial on differentiation of pulmonary nodules. The aims of this trial were to investigate if multimodality imaging is of advantage and to what extent it could benefit the patients in real clinical settings. Seventy-three subjects in whom it was difficult to establish the diagnosis and determine management of their pulmonary lesions were prospectively enrolled in this clinical trial. All subjects underwent {sup 18}F-FDG and {sup 18}F-FLT PET/CT imaging sequentially. The images were interpreted with different strategies as either individual or combined modalities. The pathological or clinical evidence during a follow-up period of more than 22 months served as the standard of truth. The diagnostic performance of each interpretation and their impact on clinical decision making was investigated. {sup 18}F-FLT/{sup 18}F-FDG PET/CT was proven to be of clinical value in improving the diagnostic confidence in 28 lung tumours, 18 tuberculoses and 27 other benign lesions. The ratio between maximum standardized uptake values of {sup 18}F-FLT and {sup 18}F-FDG was found to be of great potential in separating the three subgroups of patients. The advantage could only be obtained with the full use of the multimodality interpretation. Multimodality imaging induced substantial change in clinical management in 31.5% of the study subjects and partial change in another 12.3%. Multimodality imaging using {sup 18}F-FDG/{sup 18}F-FLT PET/CT provided the best diagnostic efficacy and the opportunity for better management in this group of clinically challenging patients with pulmonary lesions. (orig.)

  13. Acoustic imaging of underground storage tank wastes

    International Nuclear Information System (INIS)

    Mech, S.J.

    1995-09-01

    Acoustics is a potential tool to determine the properties of high level wastes stored in Underground Storage Tanks. Some acoustic properties were successfully measured by a limited demonstration conducted in 114-TX. This accomplishment provides the basis for expanded efforts to qualify techniques which depend on the acoustic properties of tank wastes. This work is being sponsored by the Department of Energy under the Office of Science and Technology. In FY-1994, limited Tank Waste Remediation Systems EM-30 support was available at Hanford and Los Alamos National Laboratory. The Massachusetts Institute of Technology (MIT) and Earth Resources Laboratory (ERL) were engaged for analysis support, and Elohi Geophysics, Inc. for seismic testing services. Westinghouse-Hanford Company provided the testing and training, supplied the special engineering and safety analysis equipment and procedures, and provided the trained operators for the actual tank operations. On 11/9/94, limited in-tank tests were successfully conducted in tank 114-TX. This stabilized Single Shell Tank was reported as containing 16.8 feet of waste, the lower 6.28 feet of which contained interstitial liquid. Testing was conducted over the lower 12 feet, between two Liquid Observation Wells thirty feet apart. The ''quick-look'' data was reviewed on-site by MIT and Elohi

  14. Radiosynthesis and initial evaluation of [{sup 18}F]-FEPPA for PET imaging of peripheral benzodiazepine receptors

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, Alan A. [PET Centre, Centre for Addiction and Mental Health, Toronto, Ontario, M5T 1R8 (Canada); Department of Psychiatry, University of Toronto, Toronto, Ontario, M5T 1R8 (Canada)], E-mail: alan.wilson@camhpet.ca; Garcia, Armando; Parkes, Jun [PET Centre, Centre for Addiction and Mental Health, Toronto, Ontario, M5T 1R8 (Canada); McCormick, Patrick [PET Centre, Centre for Addiction and Mental Health, Toronto, Ontario, M5T 1R8 (Canada); Institute of Medical Science, University of Toronto, Toronto, Ontario, M5S 1A8 (Canada); Stephenson, Karin A. [PET Centre, Centre for Addiction and Mental Health, Toronto, Ontario, M5T 1R8 (Canada); Houle, Sylvain; Vasdev, Neil [PET Centre, Centre for Addiction and Mental Health, Toronto, Ontario, M5T 1R8 (Canada); Department of Psychiatry, University of Toronto, Toronto, Ontario, M5T 1R8 (Canada)

    2008-04-15

    Introduction: A novel [{sup 18}F]-radiolabelled phenoxyanilide, [{sup 18}F]-FEPPA, has been synthesized and evaluated, in vitro and ex vivo, as a potential positron emission tomography imaging agent for the peripheral benzodiazepine receptor (PBR). Methods: [{sup 18}F]-FEPPA and two other radiotracers for imaging PBR, namely [{sup 11}C]-PBR28 and [{sup 11}C]-PBR28-d3, were synthesised and evaluated in vitro and ex vivo as potential PBR imaging agents. Results: [{sup 18}F]-FEPPA is efficiently prepared in one step from its tosylate precursor and [{sup 18}F]-fluoride in high radiochemical yields and at high specific activity. FEPPA displayed a K{sub i} of 0.07 nM for PBR in rat mitochondrial membrane preparations and a suitable lipophilicity for brain penetration (log P of 2.99 at pH 7.4). Upon intravenous injection into rats, [{sup 18}F]-FEPPA showed moderate brain uptake [standard uptake value (SUV) of 0.6 at 5 min] and a slow washout (SUV of 0.35 after 60 min). Highest uptake of radioactivity was seen in the hypothalamus and olfactory bulb, regions previously reported to be enriched in PBR in rat brain. Analysis of plasma and brain extracts demonstrated that [{sup 18}F]-FEPPA was rapidly metabolized, but no lipophilic metabolites were observed in either preparation and only 5% radioactive metabolites were present in brain tissue extracts. Blocking studies to determine the extent of specific binding of [{sup 18}F]-FEPPA in rat brain were problematic due to large perturbations in circulating radiotracer and the lack of a reference region. Conclusions: Further evaluation of the potential of [{sup 18}F]-FEPPA will require the employment of rigorous kinetic models and/or appropriate animal models.

  15. Generation and control of sound bullets with a nonlinear acoustic lens.

    Science.gov (United States)

    Spadoni, Alessandro; Daraio, Chiara

    2010-04-20

    Acoustic lenses are employed in a variety of applications, from biomedical imaging and surgery to defense systems and damage detection in materials. Focused acoustic signals, for example, enable ultrasonic transducers to image the interior of the human body. Currently however the performance of acoustic devices is limited by their linear operational envelope, which implies relatively inaccurate focusing and low focal power. Here we show a dramatic focusing effect and the generation of compact acoustic pulses (sound bullets) in solid and fluid media, with energies orders of magnitude greater than previously achievable. This focusing is made possible by a tunable, nonlinear acoustic lens, which consists of ordered arrays of granular chains. The amplitude, size, and location of the sound bullets can be controlled by varying the static precompression of the chains. Theory and numerical simulations demonstrate the focusing effect, and photoelasticity experiments corroborate it. Our nonlinear lens permits a qualitatively new way of generating high-energy acoustic pulses, which may improve imaging capabilities through increased accuracy and signal-to-noise ratios and may lead to more effective nonintrusive scalpels, for example, for cancer treatment.

  16. Frequency Representation: Visualization and Clustering of Acoustic Data Using Self-Organizing Maps.

    Science.gov (United States)

    Guo, Xinhua; Sun, Song; Yu, Xiantao; Wang, Pan; Nakamura, Kentaro

    2017-11-01

    Extraction and display of frequency information in three-dimensional (3D) acoustic data are important steps to analyze object characteristics, because the characteristics, such as profiles, sizes, surface structures, and material properties, may show frequency dependence. In this study, frequency representation (FR) based on phase information in multispectral acoustic imaging (MSAI) is proposed to overcome the limit of intensity or amplitude information in image display. Experiments are performed on 3D acoustic data collected from a rigid surface engraved with five different letters. The results show that the proposed FR technique can not only identify the depth of the five letters by the colors representing frequency characteristics but also demonstrate the 3D image of the five letters, providing more detailed characteristics that are unavailable by conventional acoustic imaging.

  17. A cross-correlation objective function for least-squares migration and visco-acoustic imaging

    KAUST Repository

    Dutta, Gaurav

    2014-08-05

    Conventional acoustic least-squares migration inverts for a reflectivity image that best matches the amplitudes of the observed data. However, for field data applications, it is not easy to match the recorded amplitudes because of the visco-elastic nature of the earth and inaccuracies in the estimation of source signature and strength at different shot locations. To relax the requirement for strong amplitude matching of least-squares migration, we use a normalized cross-correlation objective function that is only sensitive to the similarity between the predicted and the observed data. Such a normalized cross-correlation objective function is also equivalent to a time-domain phase inversion method where the main emphasis is only on matching the phase of the data rather than the amplitude. Numerical tests on synthetic and field data show that such an objective function can be used as an alternative to visco-acoustic least-squares reverse time migration (Qp-LSRTM) when there is strong attenuation in the subsurface and the estimation of the attenuation parameter Qp is insufficiently accurate.

  18. A cross-correlation objective function for least-squares migration and visco-acoustic imaging

    KAUST Repository

    Dutta, Gaurav; Sinha, Mrinal; Schuster, Gerard T.

    2014-01-01

    Conventional acoustic least-squares migration inverts for a reflectivity image that best matches the amplitudes of the observed data. However, for field data applications, it is not easy to match the recorded amplitudes because of the visco-elastic nature of the earth and inaccuracies in the estimation of source signature and strength at different shot locations. To relax the requirement for strong amplitude matching of least-squares migration, we use a normalized cross-correlation objective function that is only sensitive to the similarity between the predicted and the observed data. Such a normalized cross-correlation objective function is also equivalent to a time-domain phase inversion method where the main emphasis is only on matching the phase of the data rather than the amplitude. Numerical tests on synthetic and field data show that such an objective function can be used as an alternative to visco-acoustic least-squares reverse time migration (Qp-LSRTM) when there is strong attenuation in the subsurface and the estimation of the attenuation parameter Qp is insufficiently accurate.

  19. Synthesis and evaluation of 4-[18F]fluorothalidomide for the in vivo studies of angiogenesis

    International Nuclear Information System (INIS)

    Kim, Dong Hyun; Choe, Yearn Seong; Jung, Kyoung-Ho; Lee, Kyung-Han; Choi, Yong; Kim, Byung-Tae

    2006-01-01

    In this study, we prepared 2-(2,6-dioxopiperidin-3-yl)-4-[ 18 F]fluoroisoindole-1,3-dione (4-[ 18 F]fluorothalidomide; [ 18 F]1) for the in vivo studies of angiogenesis. Radiochemical synthesis of [ 18 F]1 was carried out by labeling 4-trimethylammoniumthalidomide trifluoromethanesulfonate with nBu 4 N[ 18 F]F in dimethyl sulfoxide (DMSO), followed by reverse-phase HPLC purification. Decay-corrected radiochemical yield of [ 18 F]1 was 50-60%, with an effective specific activity of 42-120 GBq/μmol (end of synthesis). Incubation of the radioligand with human umbilical vein endothelial cells (HUVEC-C; American Type Culture Collection) showed a time-dependent increase in the uptake of the radioligand, and the uptake was inhibited by 8-11% in the presence of 10 μM thalidomide, indicating nonspecific binding of the radioligand. Positron emission tomography (PET) images of mice implanted with tumors in their right flanks revealed a marked accumulation of radioactivity in the livers, kidneys and bladders of the mice, and brain uptake appeared at approximately 40 min after injection. However, no radioactivity uptake was detected in the implanted tumor. Thin-layer chromatography (TLC), HPLC and LC-MS analyses of mouse liver microsomal metabolites of [ 18 F]1 and 1 with or without nicotinamide adenine dinucleotide phosphate (NADPH) clearly revealed that the radioligand did not go through metabolic activation but underwent nonenzymatic hydrolysis at physiological pH. Therefore, these results would appear to indicate that [ 18 F]1 may not be suitable for the in vivo studies of angiogenesis at least in mice, although it was reported that thalidomide and/or its hydrolysis products may be responsible for its activity in humans

  20. Comparison of Positron Emission Tomography Using 2-[18F]-fluoro-2-deoxy-D-glucose and 3-deoxy-3-[18F]-fluorothymidine in Lung Cancer Imaging

    Science.gov (United States)

    Wang, Fu-Li; Tan, Ye-Ying; Gu, Xiang-Min; Li, Tian-Ran; Lu, Guang-Ming; Liu, Gang; Huo, Tian-Long

    2016-01-01

    Background: The detection of solitary pulmonary nodules (SPNs) that may potentially develop into a malignant lesion is essential for early clinical interventions. However, grading classification based on computed tomography (CT) imaging results remains a significant challenge. The 2-[18F]-fluoro-2-deoxy-D-glucose (18F-FDG) positron emission tomography (PET)/CT imaging produces both false-positive and false-negative findings for the diagnosis of SPNs. In this study, we compared 18F-FDG and 3-deoxy-3-[18F]-fluorothymidine (18F-FLT) in lung cancer PET/CT imaging. Methods: The binding ratios of the two tracers to A549 lung cancer cells were calculated. The mouse lung cancer model was established (n = 12), and micro-PET/CT analysis using the two tracers was performed. Images using the two tracers were collected from 55 lung cancer patients with SPNs. The correlation among the cell-tracer binding ratios, standardized uptake values (SUVs), and Ki-67 proliferation marker expression were investigated. Results: The cell-tracer binding ratio for the A549 cells using the 18F-FDG was greater than the ratio using 18F-FLT (P < 0.05). The Ki-67 expression showed a significant positive correlation with the 18F-FLT binding ratio (r = 0.824, P < 0.01). The tumor-to-nontumor uptake ratio of 18F-FDG imaging in xenografts was higher than that of 18F-FLT imaging. The diagnostic sensitivity, specificity, and the accuracy of 18F-FDG for lung cancer were 89%, 67%, and 73%, respectively. Moreover, the diagnostic sensitivity, specificity, and the accuracy of 18F-FLT for lung cancer were 71%, 79%, and 76%, respectively. There was an obvious positive correlation between the lung cancer Ki-67 expression and the mean maximum SUV of 18F-FDG and 18F-FLT (r = 0.658, P < 0.05 and r = 0.724, P < 0.01, respectively). Conclusions: The 18F-FDG uptake ratio is higher than that of 18F-FLT in A549 cells at the cellular level. 18F-FLT imaging might be superior for the quantitative diagnosis of lung tumor

  1. Biological evaluation of [18F]-nifedipine as a novel PET tracer for L-type calcium channel imaging

    International Nuclear Information System (INIS)

    Sadeghpour, H.; Jalilian, A.R.; Akhlaghi, M.; Mirzaii, M.; Saddadi, F.; Shafiee, A.; Miri, R.

    2008-01-01

    Due to interesting role of dihydropyridines in cardiovascular diseases and drug resistance studies and lack of a fluorine-18 labeled imaging agent for L-type calcium channel studies, this study was designed. [ 18 F] Dimethyl 2 - (fluoromethyl) - 6 - methyl - 4 - (2 - nitrophenyl) - 1,4 - dihydropyridine - 3,5 - dicarboxylate 2 was prepared in no-carrier-added (n.c.a.) form from a starting brominated compound in one step at 80 o C in Kryptofix2.2.2/[ 18 F]. Compound 2 was administered to normal rats via their tail veins for preliminary biodistribution studies and the ID/g % of the labeled compound was determined up to 3 h post injections. Coincidence images were obtained in rats 5 to 120 min. Radiofluorination on bromo precursor gave a fluorinated compound in 95 % radiochemical purity and a 8% yield shown by RTLC and HPLC. Biodistribution studies showed that the tracer is accumulated in the heart in the first few minutes, followed by metabolism resulting in very soluble 18 F-containing metabolites eliminated through the urinary tract. In coincidence images, the target organ was shown to be the heart. Lung had high accumulation possibly due to the presence of Ca 2+ channels and/or hydrolyzing enzymes showing a significant myocardial uptake at 120 min. The data demonstrates a significant agreement with the reported L-type calcium channels throughout the animal body. To our knowledge, this is the first example of 18 F-DHPs in the literature. (authors)

  2. Multimodality Molecular Imaging of [18F]-Fluorinated Carboplatin Derivative Encapsulated in [111In]-Labeled Liposomes

    Science.gov (United States)

    Lamichhane, Narottam

    Platinum based chemotherapy is amongst the mainstream DNA-damaging agents used in clinical cancer therapy today. Agents such as cisplatin, carboplatin are clinically prescribed for the treatment of solid tumors either as single agents, in combination, or as part of multi-modality treatment strategy. Despite the potent anti-tumor activity of these drugs, overall effectiveness is still hampered by inadequate delivery and retention of drug in tumor and unwanted normal tissue toxicity, induced by non-selective accumulation of drug in normal cells and tissues. Utilizing molecular imaging and nanoparticle technologies, this thesis aims to contribute to better understanding of how to improve the profile of platinum based therapy. By developing a novel fluorinated derivative of carboplatin, incorporating a Flourine-18 (18F) moiety as an inherent part of the molecule, quantitative measures of drug concentration in tumors and normal tissues can be directly determined in vivo and within the intact individual environment. A potential impact of this knowledge will be helpful in predicting the overall response of individual patients to the treatment. Specifically, the aim of this project, therefore, is the development of a fluorinated carboplatin drug derivative with an inherent positron emission tomography (PET) imaging capability, so that the accumulation of the drug in the tumor and normal organs can be studied during the course of therapy . A secondary objective of this research is to develop a proof of concept for simultaneous imaging of a PET radiolabeled drug with a SPECT radiolabeled liposomal formulation, enabling thereby bi-modal imaging of drug and delivery vehicle in vivo. The approach is challenging because it involves development in PET radiochemistry, PET and SPECT imaging, drug liposomal encapsulation, and a dual-modal imaging of radiolabeled drug and radiolabeled vehicle. The principal development is the synthesis of fluorinated carboplatin 19F-FCP using 2

  3. Microwave Acoustics Handbook. Volume 4. Bulk Wave Velocities-Numerical Data.

    Science.gov (United States)

    1980-06-01

    p .00 * a* *~ Ol r4 000a1 .C e e0 0 C ~ armC aeC PSFCU NU . FPS WF w N C ’O’ w N 0 0 It1 P SNF .4.64 *.4 F7 N P C L *- P U NF L 6 .184 * ff .UULUFUJ...1010 10 7.7.N𔃽f3.7.s 34.3.3.3.3 U5 IL I 4 0 * 0t * t ** * t ** *7 * * . A 7)..00a00UN03 . f7 ) UN7.030*4 30 .4 *000 4m 0 M 3.0 030a. w tr 300a, a,7M 7... acca :00 C0 0 0 w l . r C O r . C t. . C=c c t r a r a e C N .4 *0 NNONU’ C’ 0’C N 4* P 00£.4.40 N 40’ N NU . 4w C N ’ O . N 4 N C ’t C U lo. ’ U

  4. Radiosynthesis of [{sup 18}F]fluoromethyldeoxyspergualin for molecular imaging of heat shock proteins

    Energy Technology Data Exchange (ETDEWEB)

    Ghosh, Pradip; Li, King C. [Department of Radiology, Nuclear Medicine Division, Methodist Hospital Research Institute, Weill Cornell Medical College, 6565 Fannin Street, MB1-066, Houston, TX 77030 (United States); Lee, Daniel Y., E-mail: dlee@tmhs.or [Department of Radiology, Nuclear Medicine Division, Methodist Hospital Research Institute, Weill Cornell Medical College, 6565 Fannin Street, MB1-066, Houston, TX 77030 (United States)

    2011-03-15

    To probe the in vivo role of stress response factors in normal physiology and in solid tumors we have designed a stable {sup 18}F-labeled molecular imaging agent based on a ligand for heat shock protein 70 (HSP70). We describe the synthesis of [{sup 18}F] fluorodeoxymethylspergualin ([{sup 18}F]MeDSG) as a new radiopharmaceutical probe using a prosthetic group, [{sup 18}F]SFB, for efficient and rapid radiolabeling. Ongoing molecular imaging studies are under way to detect HSP70 expression in tumors by positron emission tomography.

  5. HYPERDIRE. HYPERgeometric functions DIfferential REduction. MATHEMATICA based packages for differential reduction of generalized hypergeometric functions pFp-1, F1, F2, F3, F4

    International Nuclear Information System (INIS)

    Bytev, Vladimir V.; Kalmykov, Mikhail Yu.; Kniehl, Bernd A.

    2013-05-01

    HYPERDIRE is a project devoted to the creation of a set of Mathematica based programs for the differential reduction of hypergeometric functions. The current version includes two parts: one, pfq, is relevant for manipulations of hypergeometric functions p+1 F p , and the second one, AppellF1F4, for manipulations with Appell hypergeometric functions F 1 , F 2 , F 3 , F 4 of two variables.

  6. A First Report on [18F]FPRGD2 PET/CT Imaging in Multiple Myeloma

    Directory of Open Access Journals (Sweden)

    Nadia Withofs

    2017-01-01

    Full Text Available An observational study was set up to assess the feasibility of [F18]FPRGD2 PET/CT for imaging patients with multiple myeloma (MM and to compare its detection rate with low dose CT alone and combined [F18]NaF/[F18]FDG PET/CT images. Four patients (2 newly diagnosed patients and 2 with relapsed MM were included and underwent whole-body PET/CT after injection of [F18]FPRGD2. The obtained images were compared with results of low dose CT and already available results of a combined [F18]NaF/[F18]FDG PET/CT. In total, 81 focal lesions (FLs were detected with PET/CT and an underlying bone destruction or fracture was seen in 72 (89% or 8 (10% FLs, respectively. Fewer FLs (54% were detected by [F18]FPRGD2 PET/CT compared to low dose CT (98% or [F18]NaF/[F18]FDG PET/CT (70% and all FLs detected with [F18]FPRGD2 PET were associated with an underlying bone lesion. In one newly diagnosed patient, more [F18]FPRGD2 positive lesions were seen than [F18]NaF/[F18]FDG positive lesions. This study suggests that [F18]FPRGD2 PET/CT might be less useful for the detection of myeloma lesions in patients with advanced disease as all FLs with [F18]FPRGD2 uptake were already detected with CT alone.

  7. Anesthesia condition for {sup 18}F-FDG imaging of lung metastasis tumors using small animal PET

    Energy Technology Data Exchange (ETDEWEB)

    Woo, Sang-Keun; Lee, Tae Sup; Kim, Kyeong Min; Kim, June-Youp; Jung, Jae Ho; Kang, Joo Hyun [Division of Nuclear Medicine and RI Application, Korea Institute of Radiological and Medical Sciences (KIRAMS), Nowon-Gu, Seoul 139-706 (Korea, Republic of); Cheon, Gi Jeong [Division of Nuclear Medicine and RI Application, Korea Institute of Radiological and Medical Sciences (KIRAMS), Nowon-Gu, Seoul 139-706 (Korea, Republic of); Department of Nuclear Medicine, Korea Institute of Radiological and Medical Sciences (KIRAMS), Nowon-Gu, Seoul 139-706 (Korea, Republic of)], E-mail: larry@kcch.re.kr; Choi, Chang Woon; Lim, Sang Moo [Division of Nuclear Medicine and RI Application, Korea Institute of Radiological and Medical Sciences (KIRAMS), Nowon-Gu, Seoul 139-706 (Korea, Republic of); Department of Nuclear Medicine, Korea Institute of Radiological and Medical Sciences (KIRAMS), Nowon-Gu, Seoul 139-706 (Korea, Republic of)

    2008-01-15

    Small animal positron emission tomography (PET) with {sup 18}F-FDG has been increasingly used for tumor imaging in the murine model. The aim of this study was to establish the anesthesia condition for imaging of lung metastasis tumor using small animal {sup 18}F-FDG PET. Methods: To determine the impact of anesthesia on {sup 18}F-FDG distribution in normal mice, five groups were studied under the following conditions: no anesthesia, ketamine and xylazine (Ke/Xy), 0.5% isoflurane (Iso 0.5), 1% isoflurane (Iso 1) and 2% isoflurane (Iso 2). The ex vivo counting, standard uptake value (SUV) image and glucose SUV of {sup 18}F-FDG in various tissues were evaluated. The {sup 18}F-FDG images in the lung metastasis tumor model were obtained under no anesthesia, Ke/Xy and Iso 0.5, and registered with CT image to clarify the tumor region. Results: Blood glucose concentration and muscle uptake of {sup 18}F-FDG in the Ke/Xy group markedly increased more than in the other groups. The Iso 2 group increased {sup 18}F-FDG uptake in heart compared with the other groups. The Iso 0.5 anesthesized group showed the lowest {sup 18}F-FDG uptake in heart and chest wall. The small size of lung metastasis tumor (2 mm) was clearly visualized by {sup 18}F-FDG image with the Iso 0.5 anesthesia. Conclusion: Small animal {sup 18}F-FDG PET imaging with Iso 0.5 anesthesia was appropriate for the detection of lung metastasis tumor. To acquire {sup 18}F-FDG PET images with small animal PET, the type and level of anesthetic should be carefully considered to be suitable for the visualization of target tissue in the experimental model.

  8. Transmission of F4+ E. coli in groups of early weaned piglets

    NARCIS (Netherlands)

    Geenen, P.L.; Döpfer, D.; Meulen, van der J.; Jong, de M.C.M.

    2005-01-01

    The aim of this study was to estimate transmission parameters of enterotoxigenic F4+ Escherichia coli F4 (F4+ E. coli) in groups of early weaned piglets with F4-receptor-positive (F4R+) and F4-receptor-negative piglets (F4R[minus sign]). Transmission of F4+ E. coli was quantified in four

  9. High-resolution(18)F-fluorodeoxyglucose positron emission tomography and magnetic resonance imaging for pituitary adenoma detection in Cushing disease.

    Science.gov (United States)

    Chittiboina, Prashant; Montgomery, Blake K; Millo, Corina; Herscovitch, Peter; Lonser, Russell R

    2015-04-01

    OBJECT High-resolution PET (hrPET) performed using a high-resolution research tomograph is reported as having a resolution of 2 mm and could be used to detect corticotroph adenomas through uptake of(18)F-fluorodeoxyglucose ((18)F-FDG). To determine the sensitivity of this imaging modality, the authors compared(18)F-FDG hrPET and MRI detection of pituitary adenomas in Cushing disease (CD). METHODS Consecutive patients with CD who underwent preoperative(18)F-FDG hrPET and MRI (spin echo [SE] and spoiled gradient recalled [SPGR] sequences) were prospectively analyzed. Standardized uptake values (SUVs) were calculated from hrPET and were compared with MRI findings. Imaging findings were correlated to operative and histological findings. RESULTS Ten patients (7 females and 3 males) were included (mean age 30.8 ± 19.3 years; range 11-59 years). MRI revealed a pituitary adenoma in 4 patients (40% of patients) on SE and 7 patients (70%) on SPGR sequences.(18)F-FDG hrPET demonstrated increased(18)F-FDG uptake consistent with an adenoma in 4 patients (40%; adenoma size range 3-14 mm). Maximum SUV was significantly higher for(18)F-FDG hrPET-positive tumors (difference = 5.1, 95% CI 2.1-8.1; p = 0.004) than for(18)F-FDG hrPET-negative tumors.(18)F-FDG hrPET positivity was not associated with tumor volume (p = 0.2) or dural invasion (p = 0.5). Midnight and morning ACTH levels were associated with(18)F-FDG hrPET positivity (p = 0.01 and 0.04, respectively) and correlated with the maximum SUV (R = 0.9; p = 0.001) and average SUV (R = 0.8; p = 0.01). All(18)F-FDG hrPET-positive adenomas had a less than a 180% ACTH increase and(18)F-FDG hrPET-negative adenomas had a greater than 180% ACTH increase after CRH stimulation (p = 0.03). Three adenomas were detected on SPGR MRI sequences that were not detected by(18)F-FDG hrPET imaging. Two adenomas not detected on SE (but no adenomas not detected on SPGR) were detected on(18)F-FDG hrPET. CONCLUSIONS While(18)F-FDG hrPET imaging can

  10. PET imaging with [18F]fluoroethoxybenzovesamicol ([18F]FEOBV) following selective lesion of cholinergic pedunculopontine tegmental neurons in rat

    International Nuclear Information System (INIS)

    Cyr, Marilyn; Parent, Maxime J.; Mechawar, Naguib; Rosa-Neto, Pedro; Soucy, Jean-Paul; Aliaga, Antonio; Kostikov, Alexey; Maclaren, Duncan A.A.; Clark, Stewart D.; Bedard, Marc-Andre

    2014-01-01

    Introduction: [ 18 F]fluoroethoxybenzovesamicol ([ 18 F]FEOBV) is a PET radiotracer with high selectivity and specificity to the vesicular acetylcholine transporter (VAChT). It has been shown to be a sensitive in vivo measurement of changes of cholinergic innervation densities following lesion of the nucleus basalis of Meynert (NBM) in rat. The current study used [ 18 F]FEOBV with PET imaging to detect the effect of a highly selective lesion of the pedunculopontine (PPTg) nucleus in rat. Methods: After bilateral and selective lesions of the PPTg cholinergic neurons, rats were scanned using [ 18 F]FEOBV, then sacrificed, and their brain tissues collected for immunostaining and quantification of the VAChT. Results: Comparisons with control rats revealed that cholinergic losses can be detected in the brainstem, lateral thalamus, and pallidum by using both in vivo imaging methods with [ 18 F]FEOBV, and ex vivo measurements. In the brainstem PPTg area, significant correlations were observed between in vivo and ex vivo measurements, while this was not the case in the thalamic and pallidal projection sites. Conclusions: These findings support PET imaging with [ 18 F]FEOBV as a reliable in vivo method for the detection of neuronal terminal losses resulting from lesion of the PPTg. Useful applications can be found in the study of neurodegenerative diseases in human, such as Parkinson’s disease, multiple system atrophy, progressive supranuclear palsy, or dementia with Lewy bodies

  11. Imaging findings and literature review of {sup 18}F-FDG PET/CT in primary systemic AL amyloidosis

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Joo Hee; Lee, Ga Yeon; Kim, Seok Jin; Kim, Ki Hyun; Jeon, Eun Seok; Lee, Kyung Han; Kim, Byung Tae; Choi, Joon Young [Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of)

    2015-09-15

    Although several case reports and case series have described {sup 18}F-FDG PET/CT in amyloidosis, the value of {sup 18}F-FDG PET/CT for diagnosing amyloidosis has not been clarified. We investigated the imaging findings of {sup 18}F-FDG PET/CT in patients with primary systemic AL amyloidosis. Subjects were 15 patients (M:F = 12:3; age, 61.5 ± 7.4 years) with histologically confirmed primary systemic AL amyloidosis who underwent pretreatment {sup 18}F-FDG PET/CT to rule out the possibility of malignancy or for initial workup of alleged cancer. For involved organs, visual and semiquantitative analyses were performed on {sup 18}F-FDG PET/CT images. In total, 22 organs (10 hearts, 5 kidneys, 2 stomachs, 2 colons, 1 ileum, 1 pancreas, and 1 liver) were histologically confirmed to have primary systemic AL amyloidosis. F-FDG uptake was significantly increased in 15 of the 22 organs (68.2 %; 10 hearts, 2 kidneys, 1 colon, 1 ileum, and 1 liver; SUV{sub max} = 7.0 ± 3.2, range 2.1–14.1). However, in 11 of 15 PET-positive organs (78.6 %; 10 hearts and the ileum), it was difficult to differentiate pathological uptake from physiological uptake. Definitely abnormal {sup 18}F-FDG uptake was found in only 4 of the 22 organs (18.2 %; 2 kidneys, 1 colon, and the liver). {sup 18}F-FDG uptake was negative for pancreas and gastric lesions. Although {sup 18}F-FDG PET/CT showed high uptake in two-thirds of the organs involving primary systemic AL amyloidosis, its sensitivity appeared to be low to make differentiation of pathological uptake from physiological uptake. However, due to the small number of cases, further study for the role of {sup 18}F-FDG PET/CT in amyloidosis will be warranted.

  12. Guidelines for 18F-FDG PET and PET-CT imaging in paediatric oncology

    DEFF Research Database (Denmark)

    Stauss, J.; Franzius, C.; Pfluger, T.

    2008-01-01

    tomography ((18)F-FDG PET) in paediatric oncology. The Oncology Committee of the European Association of Nuclear Medicine (EANM) has published excellent procedure guidelines on tumour imaging with (18)F-FDG PET (Bombardieri et al., Eur J Nucl Med Mol Imaging 30:BP115-24, 2003). These guidelines, published...

  13. IgG4-Related Disease Simulating Carcinoma Colon With Diffuse Peritoneal Carcinomatosis on 18F-FDG PET/CT.

    Science.gov (United States)

    Vadi, Shelvin Kumar; Parihar, Ashwin Singh; Kumar, Rajender; Singh, Harmandeep; Mittal, Bhagwant Rai; Bal, Amanjit; Sinha, Saroj Kumar

    2018-05-14

    IgG4-related disease (IgG4-RD) continues to be a diagnostic challenge and a great mimicker of malignancies. We report here a case of young man who presented with subacute intestinal obstruction with initial imaging and clinical features suggestive of carcinoma colon. 18F-FDG PET/CT showed diffuse peritoneal carcinomatosis pattern typically seen with abdominal malignancies. However, the histopathology and the raised IgG4 levels diagnosed it to be IgG4-RD. Although 18F-FDG PET/CT has typical patterns corresponding to the multisystemic involvement of IgG4-RD, the index case did not show any such findings.

  14. Investigation of the multiphotonic excitation processes of the 4f{sup 2} 5d configuration in LiYF{sub 4}, LiLuF{sub 4} and BaY{sub 2}F{sub 8} crystals doped with trivalent neodymium; Investigacao dos processos de excitacao multifotonica da configuracao 4f{sup 2} 5d nos cristais de LiYF{sub 4}, LiLuF{sub 4} e BaY{sub 2}F{sub 8} dopados com neodimio trivalente

    Energy Technology Data Exchange (ETDEWEB)

    Librantz, Andre Felipe Henriques

    2004-07-01

    Ultraviolet (UV) fluorescence of Nd{sup 3+} ions induced by multistep laser excitation was investigated in Nd-doped LiYF{sub 4} (YLF), LiLuF{sub 4} (LLF) and BaY{sub 2}F{sub 8} (BaYF) crystals using a technique of time-resolved spectroscopy. The observed UV luminescence was due to transitions between the bottom of 4f{sup 2} 5d configuration and the 4f{sup 3} states of Nd{sup 3+} ions. The lower excited state 4f {sup 2}({sup 3}H)5d [{sup 4}K{sub 11/2}] was reached by three stepwise absorptions of photons at 521 nm (green) and 478 nm (blue) of a short pulse laser excitation. The three sequential absorptions at 478 nm constitutes a new multiphoton excitation process of Nd{sup 3+} in these crystals with the following excitation sequence: {sup 4}I{sub 9/2} + hv(480 nm){yields} {sup 2}G(1){sub 9/2} + hv(480 nm){yields} {sup 2}F(2){sub 7/2} + hv(480 nm){yields} 4f {sup 2}({sup 3}H)5d [{sup 4}K{sub 9/2}] (excited state at {approx} 63000 cm{sup -1}). The observed UV emissions from [{sup 4}K{sub 11/2}] state have a lifetime of 35 ns (parity allowed) and are: broadband in contrast to UV emissions from 4f{sup 3} configuration, which are also present in the luminescence investigation but having longer lifetime (8 {mu}s) and structures composed of narrow lines. The excitation spectrum of fast UV luminescence exhibited different structure depending on the excitation geometry ({sigma} or {pi}) with respect to the c-axis of the crystal. It was seen two new emissions from [{sup 4}K{sub 11/2}] and {sup 2}F(2){sub 5/2} states near 528 nm, which modified the branching ratio of the bottom of the 4f{sup 2} 5d configuration ({approx} 55500 cm{sup -1} for the YLF and LLF crystals and {approx}-53700 cm{sup -1} for the BaYF crystal). The equivalent cross-section of three and two excitation process was estimated at 521 nm by solving the rate equations of the system under short laser excitation, which leads us to infer that is possible to have laser action under pulsed laser pumping with

  15. PVT Degradation Studies: Acoustic Diagnostics

    Energy Technology Data Exchange (ETDEWEB)

    Dib, Gerges [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Tucker, Brian J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Kouzes, Richard T. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Smith, Philip J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2017-04-01

    Under certain environmental conditions, polyvinyl toluene (PVT) plastic scintillator has been observed to undergo internal fogging. This document reports on a study of acoustic techniques to determine whether they can provide a diagnostic for the fogging of PVT. Different ultrasound techniques were employed for detecting the level of internal fogging in PVT, including wave velocity measurements, attenuation, nonlinear acoustics, and acoustic microscopy. The results indicate that there are linear relations between the wave velocity and wave attenuation with the level of internal fogging. The effects of fogging on ultrasound wave attenuation is further verified by acoustic microscopy imaging, where regions with fog in the specimen demonstration higher levels of attenuation compared to clear regions. Results from the nonlinear ultrasound measurements were inconclusive due to high sensitivities to transducer coupling and fixture variabilities.

  16. 4f-5d hybridization in a high k dielectric

    International Nuclear Information System (INIS)

    Losovyj, Ya.B.; Tang, Jinke; Wang, Wendong; Hong Yuanjia; Palshin, Vadim; Tittsworth, Roland

    2006-01-01

    While intra-atomic f-d hybridization is expected, experimental confirmation of f-d hybridization in the photoemission final state leading to 4f band structure has been limited to 5f systems and compound systems with very shallow 4f levels. We demonstrate that core 4f states can contribute to the valence band structure in a wide band gap dielectric, in this case HfO 2 in the photoemission final state. In spite of the complications of sample charging, we find evidence of symmetry in the shallow 4f levels and wave vector dependent band dispersion, the latter consistent with the crystal structure of HfO 2

  17. Synthesis and comparative biological evaluation of L- and D-isomers of {sup 18}F-labeled fluoroalkyl phenylalanine derivatives as tumor imaging agents

    Energy Technolog