1
|
Bouchendouka A, Fellah ZEA, Nguyen CT, Ogam E, Perrot C, Duval A, Depollier C. Improving acoustic wave propagation models in highly attenuating porous materials. J Acoust Soc Am 2024; 155:206-217. [PMID: 38180154 DOI: 10.1121/10.0024008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2023] [Accepted: 12/05/2023] [Indexed: 01/06/2024]
Abstract
This article presents an improved and extended modeling approach for acoustic wave propagation in rigid porous materials, focusing on examples, such as plastic foams used for noise reduction in automotive applications. We demonstrate that the classical model (Johnson-Champoux-Allard) in the asymptotic high-frequency limit, widely employed in the literature, fails to accurately reconstruct the transmitted acoustic signal through high absorbent porous materials characterized by significant wave attenuation. The study focuses on the airborne ultrasonic frequency range (30-200 kHz). To address this limitation, we introduce new non-acoustic parameters Σ and V for viscous effects, and Σ' and V' for thermal effects, with surface and volumetric dimensions, respectively, allowing for the reconstruction of the transmitted signal and accurate modeling of the pronounced acoustic attenuation within the material. These parameters are incorporated into the expansion on skin depths of the dynamic tortuosity α(ω) and thermal tortuosity α' (ω) response functions, which describe the inertial-viscous and thermal interactions between the fluid and the solid, respectively. This novel modeling approach enables a more comprehensive study of high attenuating porous media, which are crucial for effective noise reduction. Additionally, it opens up new possibilities for characterization beyond the capabilities of current models.
Collapse
Affiliation(s)
- A Bouchendouka
- Aix Marseille Univ, CNRS, Centrale Marseille, LMA UMR 7031, Marseille, France
| | - Z E A Fellah
- Aix Marseille Univ, CNRS, Centrale Marseille, LMA UMR 7031, Marseille, France
| | - C T Nguyen
- Univ Gustave Eiffel, Univ Paris Est Creteil, CNRS, UMR 8208, MSME, F-77454 Marne-la-Vallée, France
| | - E Ogam
- Aix Marseille Univ, CNRS, Centrale Marseille, LMA UMR 7031, Marseille, France
| | - C Perrot
- Univ Gustave Eiffel, Univ Paris Est Creteil, CNRS, UMR 8208, MSME, F-77454 Marne-la-Vallée, France
| | - A Duval
- Trèves products, services and innovation, 2-4 rue Emile Arqu'es, CS 70017, 51686 Reims Cedex 2, France
| | - C Depollier
- Acoustics Laboratory of the University of Le Mans (LAUM), UMR 6613, Institut d'Acoustique - Graduate School (IA-GS), CNRS, Le Mans University, Le Mans, France
| |
Collapse
|
2
|
Orth LE, Ellingson AS, Azimi SF, Martinez JT, Alhadad AA, Tran BC, Allen CW, Nguyen CT, Duong T, Burkdoll JS, Yoo J, Blackmer AB, Jeffres MN. Allowable room temperature excursions for refrigerated medications: A 20-year review. Am J Health Syst Pharm 2022; 79:1296-1300. [PMID: 35451022 DOI: 10.1093/ajhp/zxac118] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
DISCLAIMER In an effort to expedite the publication of articles, AJHP is posting manuscripts online as soon as possible after acceptance. Accepted manuscripts have been peer-reviewed and copyedited, but are posted online before technical formatting and author proofing. These manuscripts are not the final version of record and will be replaced with the final article (formatted per AJHP style and proofed by the authors) at a later time. PURPOSE The aim of this review was to build upon previous literature describing the maximum duration for which refrigerated medications can tolerate room temperature excursions while maintaining stability and potency. METHODS During a 12-month period ending in June 2021, the prescribing information and published monographs from multiple pharmacy compendia were reviewed for all medications and biologic products approved by the US Food and Drug Administration (FDA) for human use since January 2000. Products that were subsequently withdrawn from the US market were excluded. When temperature excursion data was unavailable in published form, product manufacturers were surveyed via telephone and/or email. Acceptable storage information for all products for which storage is recommended at temperatures below room temperature (20-25 °C [68-77 °F]) was compiled and arranged in tabular format. RESULTS Of the 705 products or formulations approved by FDA during the predefined time period, 246 were identified as requiring storage at temperatures below room temperature. After review of available prescribing information and manufacturer communications, if applicable, acceptable periods of excursion to temperatures at room temperature or higher were identified for 214 products (87%). CONCLUSION Information related to acceptable periods of room temperature excursion was compiled for a total of 214 products approved for US distribution since 2000. The included tables may increase patient safety and decrease medication loss or related expenditures.
Collapse
Affiliation(s)
- Lucas E Orth
- Department of Clinical Pharmacy, University of Colorado Skaggs School of Pharmacy and Pharmaceutical Sciences, Aurora, CO, and Department of Pharmacy, Children's Hospital Colorado, Aurora, CO, USA
| | - Amanda S Ellingson
- Department of Clinical Pharmacy, University of Colorado Skaggs School of Pharmacy and Pharmaceutical Sciences, Aurora, CO, USA
| | - Sara F Azimi
- Department of Clinical Pharmacy, University of Colorado Skaggs School of Pharmacy and Pharmaceutical Sciences, Aurora, CO, USA
| | - Joseph T Martinez
- Department of Clinical Pharmacy, University of Colorado Skaggs School of Pharmacy and Pharmaceutical Sciences, Aurora, CO, USA
| | - Amal A Alhadad
- Department of Clinical Pharmacy, University of Colorado Skaggs School of Pharmacy and Pharmaceutical Sciences, Aurora, CO, USA
| | - Brenda C Tran
- Department of Clinical Pharmacy, University of Colorado Skaggs School of Pharmacy and Pharmaceutical Sciences, Aurora, CO, USA
| | - Chase W Allen
- Department of Clinical Pharmacy, University of Colorado Skaggs School of Pharmacy and Pharmaceutical Sciences, Aurora, CO, USA
| | - Cecilia T Nguyen
- Department of Clinical Pharmacy, University of Colorado Skaggs School of Pharmacy and Pharmaceutical Sciences, Aurora, CO, USA
| | - Tony Duong
- Department of Clinical Pharmacy, University of Colorado Skaggs School of Pharmacy and Pharmaceutical Sciences, Aurora, CO, USA
| | - Jordan S Burkdoll
- Department of Clinical Pharmacy, University of Colorado Skaggs School of Pharmacy and Pharmaceutical Sciences, Aurora, CO, USA
| | - Jenny Yoo
- Department of Clinical Pharmacy, University of Colorado Skaggs School of Pharmacy and Pharmaceutical Sciences, Aurora, CO, USA
| | - Allison B Blackmer
- Department of Clinical Pharmacy, University of Colorado Skaggs School of Pharmacy and Pharmaceutical Sciences, Aurora, CO, USA
| | - Meghan N Jeffres
- Department of Clinical Pharmacy, University of Colorado Skaggs School of Pharmacy and Pharmaceutical Sciences, Aurora, CO, USA
| |
Collapse
|
3
|
Langlois V, Nguyen CT, Detrez F, Guilleminot J, Perrot C. Permeability of polydisperse solid foams. Phys Rev E 2022; 105:015101. [PMID: 35193282 DOI: 10.1103/physreve.105.015101] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2021] [Accepted: 12/16/2021] [Indexed: 06/14/2023]
Abstract
The effect of polydispersity on foam permeability is investigated by numerical simulations. Foam structures are first generated by Laguerre tessellations via the Neper software and relaxed to minimize the surface energy via the Surface Evolver software. The fluid flow and permeability are then calculated by means of pore-network simulations, by considering either fully open-cell foams or foams with randomly selected closed windows. Different configurations of window aperture are used, including identical window aperture size, identical window aperture ratio, or random window aperture ratio. The main results are obtained for the case of foams having identical and uniform window aperture ratios. For such foams and at constant mean pore size, foam permeability is found to strongly increase with the polydispersity degree. The numerical results are employed to discuss the validity of the mean pressure field assumption used to calculate the foam permeability, the effect of small pores, and the definition of an equivalent Kelvin foam size. We show that as long as the fluctuations of the window aperture ratio remain low, foam permeability can be estimated by using the mean pressure field hypothesis. The weak effect of small pores on permeability is related to their small contribution to the overall fluid volume fraction. Finally, various estimations of the equivalent Kelvin foam size based on pore-size distribution are proposed.
Collapse
Affiliation(s)
- V Langlois
- Navier, Univ Gustave Eiffel, Ecole des Ponts, CNRS, F-77454 Marne-la-Vallée, France
| | - C T Nguyen
- MSME, Univ Gustave Eiffel, CNRS UMR 8208, Univ Paris Est Creteil, F-77454 Marne-la-Vallée, France
| | - F Detrez
- MSME, Univ Gustave Eiffel, CNRS UMR 8208, Univ Paris Est Creteil, F-77454 Marne-la-Vallée, France
| | - J Guilleminot
- Department of Civil and Environmental Engineering, Duke University, Durham, North Carolina 27708, USA
| | - C Perrot
- MSME, Univ Gustave Eiffel, CNRS UMR 8208, Univ Paris Est Creteil, F-77454 Marne-la-Vallée, France
| |
Collapse
|
4
|
Hodgkinson V, Lounsberry J, M'Dahoma S, Russell A, Jewett G, Benstead T, Brais B, Campbell C, Johnston W, Lochmüller H, McCormick A, Nguyen CT, O'Ferrall E, Oskoui M, Abrahao A, Briemberg H, Bourque PR, Botez S, Cashman N, Chapman K, Chrestian N, Crone M, Dobrowolski P, Dojeiji S, Dowling JJ, Dupré N, Genge A, Gonorazky H, Grant I, Hasal S, Izenberg A, Kalra S, Katzberg H, Krieger C, Leung E, Linassi G, Mackenzie A, Mah JK, Marrero A, Massie R, Matte G, McAdam L, McMillan H, Melanson M, Mezei MM, O'Connell C, Pfeffer G, Phan C, Plamondon S, Poulin C, Rodrigue X, Schellenberg K, Selby K, Sheriko J, Shoesmith C, Smith RG, Taillon M, Taylor S, Venance S, Warman-Chardon J, Worley S, Zinman L, Korngut L. The Canadian Neuromuscular Disease Registry 2010-2019: A Decade of Facilitating Clinical Research Througha Nationwide, Pan-NeuromuscularDisease Registry. J Neuromuscul Dis 2021; 8:53-61. [PMID: 32925088 PMCID: PMC7902956 DOI: 10.3233/jnd-200538] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
We report the recruitment activities and outcomes of a multi-disease neuromuscular patient registry in Canada. The Canadian Neuromuscular Disease Registry (CNDR) registers individuals across Canada with a confirmed diagnosis of a neuromuscular disease. Diagnosis and contact information are collected across all diseases and detailed prospective data is collected for 5 specific diseases: Amyotrophic Lateral Sclerosis (ALS), Duchenne Muscular Dystrophy (DMD), Myotonic Dystrophy (DM), Limb Girdle Muscular Dystrophy (LGMD), and Spinal Muscular Atrophy (SMA). Since 2010, the CNDR has registered 4306 patients (1154 pediatric and 3148 adult) with 91 different neuromuscular diagnoses and has facilitated 125 projects (73 academic, 3 not-for-profit, 3 government, and 46 commercial) using registry data. In conclusion, the CNDR is an effective and productive pan-neuromuscular registry that has successfully facilitated a substantial number of studies over the past 10 years.
Collapse
Affiliation(s)
- V Hodgkinson
- Department of Clinical Neurosciences, and Hotchkiss Brain Institute, University of Calgary, Calgary, Canada
| | - J Lounsberry
- Department of Clinical Neurosciences, and Hotchkiss Brain Institute, University of Calgary, Calgary, Canada
| | - S M'Dahoma
- Department of Clinical Neurosciences, and Hotchkiss Brain Institute, University of Calgary, Calgary, Canada
| | - A Russell
- Department of Clinical Neurosciences, and Hotchkiss Brain Institute, University of Calgary, Calgary, Canada
| | - G Jewett
- Department of Clinical Neurosciences, and Hotchkiss Brain Institute, University of Calgary, Calgary, Canada
| | - T Benstead
- Division of Neurology, Dalhousie University, Halifax, Canada
| | - B Brais
- Montreal Neurological Institute and Hospital, Montreal, Canada
| | - C Campbell
- Department of Pediatrics, Children's Health Research Institute, London Health Sciences Centre, Western University, London, Canada
| | - W Johnston
- Division of Neurology, Department of Medicine, Faculty of Medicine, University of Alberta, Edmonton, Canada
| | - H Lochmüller
- Children's Hospital of Eastern Ontario, University of Ottawa, Ottawa, Canada.,Department of Medicine, The Ottawa Hospital and Brain and Mind Research Institute, University of Ottawa, Ottawa, Canada
| | - A McCormick
- Children's Hospital of Eastern Ontario, University of Ottawa, Ottawa, Canada
| | - C T Nguyen
- CHU Sainte-Justine, Université de Montréal, Montréal, Canada
| | - E O'Ferrall
- Montreal Neurological Institute and Hospital, Montreal, Canada.,Department of Neurosciences, McGill University, Montréal, Canada
| | - M Oskoui
- Department of Neurosciences, McGill University, Montréal, Canada.,Departments of Pediatrics, Montreal Children's Hospital, McGill University, Montréal, Canada
| | - A Abrahao
- Division of Neurology, Department of Medicine, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Canada
| | - H Briemberg
- GF Strong Rehabilitation Centre, University of British Columbia, Vancouver, Canada.,Division of Neurology, Department of Medicine, Vancouver General Hospital, University of British Columbia, Vancouver, Canada
| | - P R Bourque
- Division of Physical Medicine and Rehabilitation, Department of Medicine, University of Ottawa, Ottawa, Canada
| | - S Botez
- Centre Hospitalier de l'Université de Montréal (CHUM), Université de Montréal, Montréal, Canada
| | - N Cashman
- GF Strong Rehabilitation Centre, University of British Columbia, Vancouver, Canada.,Division of Neurology, Department of Medicine, Vancouver General Hospital, University of British Columbia, Vancouver, Canada
| | - K Chapman
- Division of Neurology, Department of Medicine, Vancouver General Hospital, University of British Columbia, Vancouver, Canada
| | - N Chrestian
- Department of Medicine, Université Laval, Quebec City, Canada, Neuroscience axis, CHU de Québec-Université Laval
| | - M Crone
- Division of Pediatric Neurology, Department of Neurology, University of Saskatchewan, Saskatoon, Canada
| | - P Dobrowolski
- Division of Neurology, Department of Medicine, Faculty of Medicine, University of Alberta, Edmonton, Canada
| | - S Dojeiji
- Division of Physical Medicine and Rehabilitation, Department of Medicine, University of Ottawa, Ottawa, Canada
| | - J J Dowling
- Department of Pediatrics, Sick Kids Hospital, University of Toronto, Toronto, Canada
| | - N Dupré
- Department of Medicine, Laval University, Québec City, Canada
| | - A Genge
- Department of Neurosciences, McGill University, Montréal, Canada
| | - H Gonorazky
- Department of Pediatrics, Sick Kids Hospital, University of Toronto, Toronto, Canada
| | - I Grant
- Division of Neurology, Dalhousie University, Halifax, Canada
| | - S Hasal
- Division of Pediatric Neurology, Department of Neurology, University of Saskatchewan, Saskatoon, Canada
| | - A Izenberg
- Division of Neurology, Department of Medicine, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Canada
| | - S Kalra
- Division of Neurology, Department of Medicine, Faculty of Medicine, University of Alberta, Edmonton, Canada
| | - H Katzberg
- University Health Network, University of Toronto, Toronto, Canada
| | - C Krieger
- GF Strong Rehabilitation Centre, University of British Columbia, Vancouver, Canada.,Division of Neurology, Department of Medicine, Vancouver General Hospital, University of British Columbia, Vancouver, Canada
| | - E Leung
- Department of Pediatrics and Child Health, University of Manitoba, Winnipeg, Canada
| | - G Linassi
- Department of Physical Medicine and Rehabilitation University of Saskatchewan, Saskatoon, Canada
| | - A Mackenzie
- Children's Hospital of Eastern Ontario, University of Ottawa, Ottawa, Canada
| | - J K Mah
- Department of Clinical Neurosciences, and Hotchkiss Brain Institute, University of Calgary, Calgary, Canada.,Department of Pediatrics, University of Calgary, Calgary, Canada
| | - A Marrero
- CHU Dr. Georges-L-Dumont, Université de Sherbrooke, Moncton, Canada
| | - R Massie
- Montreal Neurological Institute and Hospital, Montreal, Canada.,Department of Neurosciences, McGill University, Montréal, Canada
| | - G Matte
- Centre Hospitalier de l'Université de Montréal (CHUM), Université de Montréal, Montréal, Canada
| | - L McAdam
- Department of Pediatrics, Holland Bloorview Kids Rehabilitation Hospital, Bloorview Research Institute, University of Toronto, Toronto, Canada
| | - H McMillan
- Division of Neurology, Department of Medicine, Faculty of Medicine, University of Alberta, Edmonton, Canada
| | - M Melanson
- Department of Physical Medicine and Rehabilitation, Queen's University, Kingston, Canada
| | - M M Mezei
- Division of Neurology, Department of Medicine, Vancouver General Hospital, University of British Columbia, Vancouver, Canada
| | - C O'Connell
- Stan Cassidy Centre for Rehabilitation, Fredericton, Canada.,Faculty of Medicine, Dalhousie University, Halifax, Canada
| | - G Pfeffer
- Department of Clinical Neurosciences, and Hotchkiss Brain Institute, University of Calgary, Calgary, Canada.,Department of Medical Genetics, and Alberta Child Health Research Institute, University of Calgary, Calgary, Canada
| | - C Phan
- Division of Neurology, Department of Medicine, Faculty of Medicine, University of Alberta, Edmonton, Canada
| | - S Plamondon
- Department of Clinical Neurosciences, and Hotchkiss Brain Institute, University of Calgary, Calgary, Canada
| | - C Poulin
- Departments of Pediatrics, Montreal Children's Hospital, McGill University, Montréal, Canada
| | - X Rodrigue
- Department of Medicine, Laval University, Québec City, Canada
| | - K Schellenberg
- Department of Physical Medicine and Rehabilitation University of Saskatchewan, Saskatoon, Canada
| | - K Selby
- Division of Neurology, Department of Pediatrics, BC Children's Hospital, University of Vancouver, Vancouver, Canada
| | - J Sheriko
- Division of Neurology, Department of Pediatrics, Dalhousie University, Halifax, Canada
| | - C Shoesmith
- Division of Neurology, Clinical Neurological Sciences, Western University, London, Canada
| | - R G Smith
- Department of Pediatrics, KidsInclusive Centre for Child & Youth Development, Hotel Dieu Hospital, Queen's University, Kingston, Canada
| | - M Taillon
- Stan Cassidy Centre for Rehabilitation, Fredericton, Canada.,Faculty of Medicine, Dalhousie University, Halifax, Canada
| | - S Taylor
- Division of Neurology, Dalhousie University, Halifax, Canada
| | - S Venance
- Division of Neurology, Clinical Neurological Sciences, Western University, London, Canada
| | - J Warman-Chardon
- Department of Medicine, The Ottawa Hospital and Brain and Mind Research Institute, University of Ottawa, Ottawa, Canada
| | - S Worley
- Stan Cassidy Centre for Rehabilitation, Fredericton, Canada.,Faculty of Medicine, Dalhousie University, Halifax, Canada
| | - L Zinman
- Division of Neurology, Department of Medicine, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Canada
| | - L Korngut
- Department of Clinical Neurosciences, and Hotchkiss Brain Institute, University of Calgary, Calgary, Canada
| |
Collapse
|
5
|
Truong AD, Hong Y, Nguyen HT, Nguyen CT, Chu NT, Tran HTT, Dang HV, Lillehoj HS, Hong YH. Molecular identification and characterisation of a novel chicken leukocyte immunoglobulin-like receptor A5. Br Poult Sci 2020; 62:68-80. [PMID: 32812773 DOI: 10.1080/00071668.2020.1812524] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
1. Leukocyte immunoglobulin-like receptor A5 (LILRA5) is a key molecule that regulates the immune system. However, the LILRA5 gene has not been characterised in avian species, including chickens. The present study aimed to identify and functionally characterise LILRA5 identified from two genetically disparate chicken lines, viz., Marek's disease (MD)-resistant (R) line 6.3 and MD-susceptible (S) line 7.2. 2. Multiple sequence alignment and phylogenetic analyses confirmed that the identity and similarity homologies of amino acids of LILRA5 in chicken lines 6.3 and 7.2 ranged between 93% and 93.7%, whereas those between chicken and mammals ranged between 20.9% and 43.7% and 21.1% to 43.9%, respectively. The newly cloned LILRA5 from chicken lines 6.3 and 7.2 revealed high conservation and a close relationship with other known mammalian LILRA5 proteins. 3. The results indicated that LILRA5 from chicken lines 6.3 and 7.2 was associated with phosphorylation of Src kinases and protein tyrosine phosphatase non-receptor type 11 (SHP2), which play a regulatory role in immune functions. Moreover, the results demonstrated that LILRA5 in these lines was associated with the activation of major histocompatibility complex (MHC) class I and β2-microglobulin and induced the expression of the transporter associated with antigen processing. In addition, LILRA5 in both chicken lines activated and induced Janus kinase (JAK)-signal transducer and the activator of transcription (STAT), nuclear factor kappa B (NF-κB), phosphoinositide-3-kinase (PI3K)/protein kinase B (AKT) and the extracellular signal-regulated kinase (ERK)1/2 signalling pathways; toll-like receptors; and Th1-, Th2-, and Th17- cytokines. 4. The data suggested that LILRA5 has innate immune receptors essential for macrophage immune response and provide novel insights into the regulation of immunity and immunopathology.
Collapse
Affiliation(s)
- A D Truong
- Department of Biochemistry and Immunology, National Institute of Veterinary Research , Dong Da, Hanoi, Vietnam.,Department of Animal Science and Technology, Chung-Ang University , Anseong, Republic of Korea
| | - Y Hong
- Department of Animal Science and Technology, Chung-Ang University , Anseong, Republic of Korea
| | - H T Nguyen
- Department of Biochemistry and Immunology, National Institute of Veterinary Research , Dong Da, Hanoi, Vietnam
| | - C T Nguyen
- Department of Biochemistry and Immunology, National Institute of Veterinary Research , Dong Da, Hanoi, Vietnam
| | - N T Chu
- Department of Biochemistry and Immunology, National Institute of Veterinary Research , Dong Da, Hanoi, Vietnam
| | - H T T Tran
- Department of Biochemistry and Immunology, National Institute of Veterinary Research , Dong Da, Hanoi, Vietnam
| | - H V Dang
- Department of Biochemistry and Immunology, National Institute of Veterinary Research , Dong Da, Hanoi, Vietnam
| | - H S Lillehoj
- United States Department of Agriculture, Animal Biosciences and Biotechnology Laboratory, Agricultural Research Services , Beltsville, MD, USA
| | - Y H Hong
- Department of Animal Science and Technology, Chung-Ang University , Anseong, Republic of Korea
| |
Collapse
|
6
|
Snel GJH, van den Boomen M, Hernandez LM, Nguyen CT, Sosnovik DE, Velthuis BK, Slart RHJA, Borra RJH, Prakken NHJ. Correction to: Cardiovascular magnetic resonance native T 2 and T 2* quantitative values for cardiomyopathies and heart transplantations: a systematic review and meta-analysis. J Cardiovasc Magn Reson 2020; 22:47. [PMID: 32539820 PMCID: PMC7294619 DOI: 10.1186/s12968-020-00646-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
An amendment to this paper has been published and can be accessed via the original article.
Collapse
Affiliation(s)
- G J H Snel
- Department of Radiology, University Medical Center Groningen, University of Groningen, Hanzeplein 1, 9713, GZ, Groningen, The Netherlands.
| | - M van den Boomen
- Department of Radiology, University Medical Center Groningen, University of Groningen, Hanzeplein 1, 9713, GZ, Groningen, The Netherlands
- Department of Radiology, Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, 149 13th Street, Charlestown, MA, 02129, USA
| | - L M Hernandez
- Department of Radiology, University Medical Center Groningen, University of Groningen, Hanzeplein 1, 9713, GZ, Groningen, The Netherlands
| | - C T Nguyen
- Department of Radiology, Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, 149 13th Street, Charlestown, MA, 02129, USA
- Cardiovascular Research Center, Massachusetts General Hospital, Harvard Medical School, 149 13th Street, Charlestown, MA, 02129, USA
| | - D E Sosnovik
- Department of Radiology, Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, 149 13th Street, Charlestown, MA, 02129, USA
- Cardiovascular Research Center, Massachusetts General Hospital, Harvard Medical School, 149 13th Street, Charlestown, MA, 02129, USA
- Division of Health Sciences and Technology, Harvard-MIT, 7 Massachusetts Avenue, Cambridge, MA, 02139, USA
| | - B K Velthuis
- Department of Radiology, University Medical Center Utrecht, Heidelberglaan 100, 3584, CX, Utrecht, The Netherlands
| | - R H J A Slart
- Department of Nuclear Medicine and Molecular Imaging, University Medical Center Groningen, University of Groningen, Hanzeplein 1, 9713, GZ, Groningen, The Netherlands
- Department of Biomedical Photonic Imaging, University of Twente, Dienstweg 1, 7522, ND, Enschede, The Netherlands
| | - R J H Borra
- Department of Radiology, University Medical Center Groningen, University of Groningen, Hanzeplein 1, 9713, GZ, Groningen, The Netherlands
- Department of Nuclear Medicine and Molecular Imaging, University Medical Center Groningen, University of Groningen, Hanzeplein 1, 9713, GZ, Groningen, The Netherlands
| | - N H J Prakken
- Department of Radiology, University Medical Center Groningen, University of Groningen, Hanzeplein 1, 9713, GZ, Groningen, The Netherlands
| |
Collapse
|
7
|
Snel GJH, Hernandez LM, Slart RHJA, Nguyen CT, Sosnovik DE, van Deursen VM, Dierckx RAJO, Velthuis BK, Borra RJH, Prakken NHJ. Validation of thoracic aortic dimensions on ECG-triggered SSFP as alternative to contrast-enhanced MRA. Eur Radiol 2020; 30:5794-5804. [PMID: 32506262 PMCID: PMC7554008 DOI: 10.1007/s00330-020-06963-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2019] [Revised: 04/07/2020] [Accepted: 05/15/2020] [Indexed: 01/16/2023]
Abstract
Objectives Assessment of thoracic aortic dimensions with non-ECG-triggered contrast-enhanced magnetic resonance angiography (CE-MRA) is accompanied with motion artefacts and requires gadolinium. To avoid both motion artefacts and gadolinium administration, we evaluated the similarity and reproducibility of dimensions measured on ECG-triggered, balanced steady-state free precession (SSFP) MRA as alternative to CE-MRA. Methods All patients, with varying medical conditions, referred for thoracic aortic examination between September 2016 and March 2018, who underwent non-ECG-triggered CE-MRA and SSFP-MRA (1.5 T) were retrospectively included (n = 30). Aortic dimensions were measured after double-oblique multiplanar reconstruction by two observers at nine landmarks predefined by literature guidelines. Image quality was scored at the sinus of Valsalva, mid-ascending aorta and mid-descending aorta by semi-automatically assessing the vessel sharpness. Results Aortic dimensions showed high agreement between non-ECG-triggered CE-MRA and SSFP-MRA (r = 0.99, p < 0.05) without overestimation or underestimation of aortic dimensions in SSFP-MRA (mean difference, 0.1 mm; limits of agreement, − 1.9 mm and 1.9 mm). Intra- and inter-observer variabilities were significantly smaller with SSFP-MRA for the sinus of Valsalva and sinotubular junction. Image quality of the sinus of Valsalva was significantly better with SSFP-MRA, as fewer images were of impaired quality (3/30) than in CE-MRA (21/30). Reproducibility of dimensions was significantly better in images scored as good quality compared to impaired quality in both sequences. Conclusions Thoracic aortic dimensions measured on SSFP-MRA and non-ECG-triggered CE-MRA were similar. As expected, SSFP-MRA showed better reproducibility close to the aortic root because of lesser motion artefacts, making it a feasible non-contrast imaging alternative. Key Points • SSFP-MRA provides similar dimensions as non-ECG-triggered CE-MRA. • Intra- and inter-observer reproducibilities improve for the sinus of Valsalva and sinotubular junction with SSFP-MRA. • ECG-triggered SSFP-MRA shows better image quality for landmarks close to the aortic root in the absence of cardiac motion. Electronic supplementary material The online version of this article (10.1007/s00330-020-06963-x) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- G J H Snel
- Department of Radiology, University Medical Center Groningen, University of Groningen, Hanzeplein 1, 9713 GZ, Groningen, The Netherlands.
| | - L M Hernandez
- Department of Radiology, University Medical Center Groningen, University of Groningen, Hanzeplein 1, 9713 GZ, Groningen, The Netherlands
| | - R H J A Slart
- Department of Nuclear Medicine and Molecular Imaging, University Medical Center Groningen, University of Groningen, Hanzeplein 1, 9713 GZ, Groningen, The Netherlands
- Department of Biomedical Photonic Imaging, University of Twente, Dienstweg 1, 7522 ND, Enschede, The Netherlands
| | - C T Nguyen
- Department of Radiology, Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, 149 13th Street, Charlestown, MA, 02129, USA
- Cardiovascular Research Center, Massachusetts General Hospital, Harvard Medical School, 149 13th Street, Charlestown, MA, 02129, USA
| | - D E Sosnovik
- Department of Radiology, Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, 149 13th Street, Charlestown, MA, 02129, USA
- Cardiovascular Research Center, Massachusetts General Hospital, Harvard Medical School, 149 13th Street, Charlestown, MA, 02129, USA
- Division of Health Sciences and Technology, Harvard-MIT, 7 Massachusetts Avenue, Cambridge, MA, 02139, USA
| | - V M van Deursen
- Department of Cardiology, University Medical Center Groningen, University of Groningen, Hanzeplein 1, 9713 GZ, Groningen, The Netherlands
| | - R A J O Dierckx
- Department of Nuclear Medicine and Molecular Imaging, University Medical Center Groningen, University of Groningen, Hanzeplein 1, 9713 GZ, Groningen, The Netherlands
| | - B K Velthuis
- Department of Radiology, University Medical Center Utrecht, Heidelberglaan 100, 3584 CX, Utrecht, The Netherlands
| | - R J H Borra
- Department of Radiology, University Medical Center Groningen, University of Groningen, Hanzeplein 1, 9713 GZ, Groningen, The Netherlands
- Department of Nuclear Medicine and Molecular Imaging, University Medical Center Groningen, University of Groningen, Hanzeplein 1, 9713 GZ, Groningen, The Netherlands
| | - N H J Prakken
- Department of Radiology, University Medical Center Groningen, University of Groningen, Hanzeplein 1, 9713 GZ, Groningen, The Netherlands
| |
Collapse
|
8
|
Snel GJH, van den Boomen M, Hernandez LM, Nguyen CT, Sosnovik DE, Velthuis BK, Slart RHJA, Borra RJH, Prakken NHJ. Cardiovascular magnetic resonance native T 2 and T 2* quantitative values for cardiomyopathies and heart transplantations: a systematic review and meta-analysis. J Cardiovasc Magn Reson 2020; 22:34. [PMID: 32393281 PMCID: PMC7212597 DOI: 10.1186/s12968-020-00627-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2019] [Accepted: 04/16/2020] [Indexed: 01/19/2023] Open
Abstract
BACKGROUND The clinical application of cardiovascular magnetic resonance (CMR) T2 and T2* mapping is currently limited as ranges for healthy and cardiac diseases are poorly defined. In this meta-analysis we aimed to determine the weighted mean of T2 and T2* mapping values in patients with myocardial infarction (MI), heart transplantation, non-ischemic cardiomyopathies (NICM) and hypertension, and the standardized mean difference (SMD) of each population with healthy controls. Additionally, the variation of mapping outcomes between studies was investigated. METHODS The PRISMA guidelines were followed after literature searches on PubMed and Embase. Studies reporting CMR T2 or T2* values measured in patients were included. The SMD was calculated using a random effects model and a meta-regression analysis was performed for populations with sufficient published data. RESULTS One hundred fifty-four studies, including 13,804 patient and 4392 control measurements, were included. T2 values were higher in patients with MI, heart transplantation, sarcoidosis, systemic lupus erythematosus, amyloidosis, hypertrophic cardiomyopathy (HCM), dilated cardiomyopathy (DCM) and myocarditis (SMD of 2.17, 1.05, 0.87, 1.39, 1.62, 1.95, 1.90 and 1.33, respectively, P < 0.01) compared with controls. T2 values in iron overload patients (SMD = - 0.54, P = 0.30) and Anderson-Fabry disease patients (SMD = 0.52, P = 0.17) did both not differ from controls. T2* values were lower in patients with MI and iron overload (SMD of - 1.99 and - 2.39, respectively, P < 0.01) compared with controls. T2* values in HCM patients (SMD = - 0.61, P = 0.22), DCM patients (SMD = - 0.54, P = 0.06) and hypertension patients (SMD = - 1.46, P = 0.10) did not differ from controls. Multiple CMR acquisition and patient demographic factors were assessed as significant covariates, thereby influencing the mapping outcomes and causing variation between studies. CONCLUSIONS The clinical utility of T2 and T2* mapping to distinguish affected myocardium in patients with cardiomyopathies or heart transplantation from healthy myocardium seemed to be confirmed based on this meta-analysis. Nevertheless, variation of mapping values between studies complicates comparison with external values and therefore require local healthy reference values to clinically interpret quantitative values. Furthermore, disease differentiation seems limited, since changes in T2 and T2* values of most cardiomyopathies are similar.
Collapse
Affiliation(s)
- G J H Snel
- Department of Radiology, University Medical Center Groningen, University of Groningen, Hanzeplein 1, 9713 GZ, Groningen, The Netherlands.
| | - M van den Boomen
- Department of Radiology, University Medical Center Groningen, University of Groningen, Hanzeplein 1, 9713 GZ, Groningen, The Netherlands
- Department of Radiology, Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, 149 13th Street, Charlestown, MA, 02129, USA
| | - L M Hernandez
- Department of Radiology, University Medical Center Groningen, University of Groningen, Hanzeplein 1, 9713 GZ, Groningen, The Netherlands
| | - C T Nguyen
- Department of Radiology, Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, 149 13th Street, Charlestown, MA, 02129, USA
- Cardiovascular Research Center, Massachusetts General Hospital, Harvard Medical School, 149 13th Street, Charlestown, MA, 02129, USA
| | - D E Sosnovik
- Department of Radiology, Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, 149 13th Street, Charlestown, MA, 02129, USA
- Cardiovascular Research Center, Massachusetts General Hospital, Harvard Medical School, 149 13th Street, Charlestown, MA, 02129, USA
- Division of Health Sciences and Technology, Harvard-MIT, 7 Massachusetts Avenue, Cambridge, MA, 02139, USA
| | - B K Velthuis
- Department of Radiology, University Medical Center Utrecht, Heidelberglaan 100, 3584 CX, Utrecht, The Netherlands
| | - R H J A Slart
- Department of Nuclear Medicine and Molecular Imaging, University Medical Center Groningen, University of Groningen, Hanzeplein 1, 9713 GZ, Groningen, The Netherlands
- Department of Biomedical Photonic Imaging, University of Twente, Dienstweg 1, 7522 ND, Enschede, The Netherlands
| | - R J H Borra
- Department of Radiology, University Medical Center Groningen, University of Groningen, Hanzeplein 1, 9713 GZ, Groningen, The Netherlands
- Department of Nuclear Medicine and Molecular Imaging, University Medical Center Groningen, University of Groningen, Hanzeplein 1, 9713 GZ, Groningen, The Netherlands
| | - N H J Prakken
- Department of Radiology, University Medical Center Groningen, University of Groningen, Hanzeplein 1, 9713 GZ, Groningen, The Netherlands
| |
Collapse
|
9
|
Bhaskar MK, Riedinger R, Machielse B, Levonian DS, Nguyen CT, Knall EN, Park H, Englund D, Lončar M, Sukachev DD, Lukin MD. Experimental demonstration of memory-enhanced quantum communication. Nature 2020; 580:60-64. [PMID: 32238931 DOI: 10.1038/s41586-020-2103-5] [Citation(s) in RCA: 85] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2019] [Accepted: 01/16/2020] [Indexed: 11/09/2022]
Abstract
The ability to communicate quantum information over long distances is of central importance in quantum science and engineering1. Although some applications of quantum communication such as secure quantum key distribution2,3 are already being successfully deployed4-7, their range is currently limited by photon losses and cannot be extended using straightforward measure-and-repeat strategies without compromising unconditional security8. Alternatively, quantum repeaters9, which utilize intermediate quantum memory nodes and error correction techniques, can extend the range of quantum channels. However, their implementation remains an outstanding challenge10-16, requiring a combination of efficient and high-fidelity quantum memories, gate operations, and measurements. Here we use a single solid-state spin memory integrated in a nanophotonic diamond resonator17-19 to implement asynchronous photonic Bell-state measurements, which are a key component of quantum repeaters. In a proof-of-principle experiment, we demonstrate high-fidelity operation that effectively enables quantum communication at a rate that surpasses the ideal loss-equivalent direct-transmission method while operating at megahertz clock speeds. These results represent a crucial step towards practical quantum repeaters and large-scale quantum networks20,21.
Collapse
Affiliation(s)
- M K Bhaskar
- Department of Physics, Harvard University, Cambridge, MA, USA
| | - R Riedinger
- Department of Physics, Harvard University, Cambridge, MA, USA
| | - B Machielse
- Department of Physics, Harvard University, Cambridge, MA, USA
| | - D S Levonian
- Department of Physics, Harvard University, Cambridge, MA, USA
| | - C T Nguyen
- Department of Physics, Harvard University, Cambridge, MA, USA
| | - E N Knall
- John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA
| | - H Park
- Department of Physics, Harvard University, Cambridge, MA, USA.,Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA, USA
| | - D Englund
- Research Laboratory of Electronics, MIT, Cambridge, MA, USA
| | - M Lončar
- John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA
| | - D D Sukachev
- Department of Physics, Harvard University, Cambridge, MA, USA
| | - M D Lukin
- Department of Physics, Harvard University, Cambridge, MA, USA.
| |
Collapse
|
10
|
Nguyen CT, Sukachev DD, Bhaskar MK, Machielse B, Levonian DS, Knall EN, Stroganov P, Riedinger R, Park H, Lončar M, Lukin MD. Quantum Network Nodes Based on Diamond Qubits with an Efficient Nanophotonic Interface. Phys Rev Lett 2019; 123:183602. [PMID: 31763904 DOI: 10.1103/physrevlett.123.183602] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Revised: 09/16/2019] [Indexed: 06/10/2023]
Abstract
Quantum networks require functional nodes consisting of stationary registers with the capability of high-fidelity quantum processing and storage, which efficiently interface with photons propagating in an optical fiber. We report a significant step towards realization of such nodes using a diamond nanocavity with an embedded silicon-vacancy (SiV) color center and a proximal nuclear spin. Specifically, we show that efficient SiV-cavity coupling (with cooperativity C>30) provides a nearly deterministic interface between photons and the electron spin memory, featuring coherence times exceeding 1 ms. Employing coherent microwave control, we demonstrate heralded single photon storage in the long-lived spin memory as well as a universal control over a cavity-coupled two-qubit register consisting of a SiV and a proximal ^{13}C nuclear spin with nearly second-long coherence time, laying the groundwork for implementing quantum repeaters.
Collapse
Affiliation(s)
- C T Nguyen
- Department of Physics, Harvard University, Cambridge, Massachusetts 02138, USA
| | - D D Sukachev
- Department of Physics, Harvard University, Cambridge, Massachusetts 02138, USA
| | - M K Bhaskar
- Department of Physics, Harvard University, Cambridge, Massachusetts 02138, USA
| | - B Machielse
- Department of Physics, Harvard University, Cambridge, Massachusetts 02138, USA
- John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, USA
| | - D S Levonian
- Department of Physics, Harvard University, Cambridge, Massachusetts 02138, USA
| | - E N Knall
- John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, USA
| | - P Stroganov
- Department of Physics, Harvard University, Cambridge, Massachusetts 02138, USA
| | - R Riedinger
- Department of Physics, Harvard University, Cambridge, Massachusetts 02138, USA
| | - H Park
- Department of Physics, Harvard University, Cambridge, Massachusetts 02138, USA
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, USA
| | - M Lončar
- John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, USA
| | - M D Lukin
- Department of Physics, Harvard University, Cambridge, Massachusetts 02138, USA
| |
Collapse
|
11
|
Nguyen CT, Reuter CM, Hudson T, Li J. Evaluation of surgical site infection antibiotic prophylaxis among patients receiving antibiotics for active infection. J Hosp Infect 2019; 103:354-355. [PMID: 31185251 DOI: 10.1016/j.jhin.2019.06.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2019] [Accepted: 06/03/2019] [Indexed: 11/16/2022]
Affiliation(s)
- C T Nguyen
- Department of Pharmacy, University of Chicago Medicine, Chicago, IL, USA.
| | - C M Reuter
- Department of Specialty Pharmacy, Ochsner Health System, New Orleans, LA, USA
| | - T Hudson
- Department of Pharmacy, FirstHealth of the Carolinas, Troy, NC, USA
| | - J Li
- Department of Pharmacy, Southeast Louisiana Veteran Health Care System, New Orleans, LA, USA
| |
Collapse
|
12
|
Le TA, Nguyen CT, Bui VL, Lakosi L. Relative efficiency calibration for determining isotopic composition and age of HEU items by passive non-destructive gamma spectrometry. Appl Radiat Isot 2018; 142:220-226. [PMID: 30419455 DOI: 10.1016/j.apradiso.2018.09.023] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2018] [Revised: 09/06/2018] [Accepted: 09/17/2018] [Indexed: 10/28/2022]
Abstract
The observation of the 239 keV gamma line from 232U decay in high-enriched uranium (HEU) samples prompted us to utilize 232U (with main gamma energies of its daughters at 239, 583, 763, and 860 keV) as a mediator isotope for performing relative (intrinsic) efficiency calibration among 232U, 234U, 235U, 238U, and 214Bi isotopes. By this way, the isotopic composition and age of HEU samples can be derived from activity ratios constituted between pairs of these isotopes on the basis of a common relative efficiency calibration curve. The method proved to be a useful tool for γ-spectrometric characterization of HEU items, especially of weapon grade, shielded uranium material.
Collapse
Affiliation(s)
- T A Le
- Hungarian Academy of Sciences, Centre for Energy Research, P. O. Box 49, 1525 Budapest, Hungary; College of Science, Vietnam National University, 334, Nguyen Trai, Hanoi, Vietnam
| | - C T Nguyen
- Hungarian Academy of Sciences, Centre for Energy Research, P. O. Box 49, 1525 Budapest, Hungary
| | - V L Bui
- College of Science, Vietnam National University, 334, Nguyen Trai, Hanoi, Vietnam
| | - L Lakosi
- Hungarian Academy of Sciences, Centre for Energy Research, P. O. Box 49, 1525 Budapest, Hungary.
| |
Collapse
|
13
|
Sukachev DD, Sipahigil A, Nguyen CT, Bhaskar MK, Evans RE, Jelezko F, Lukin MD. Silicon-Vacancy Spin Qubit in Diamond: A Quantum Memory Exceeding 10 ms with Single-Shot State Readout. Phys Rev Lett 2017; 119:223602. [PMID: 29286819 DOI: 10.1103/physrevlett.119.223602] [Citation(s) in RCA: 73] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2017] [Indexed: 06/07/2023]
Abstract
The negatively charged silicon-vacancy (SiV^{-}) color center in diamond has recently emerged as a promising system for quantum photonics. Its symmetry-protected optical transitions enable the creation of indistinguishable emitter arrays and deterministic coupling to nanophotonic devices. Despite this, the longest coherence time associated with its electronic spin achieved to date (∼250 ns) has been limited by coupling to acoustic phonons. We demonstrate coherent control and suppression of phonon-induced dephasing of the SiV^{-} electronic spin coherence by 5 orders of magnitude by operating at temperatures below 500 mK. By aligning the magnetic field along the SiV^{-} symmetry axis, we demonstrate spin-conserving optical transitions and single-shot readout of the SiV^{-} spin with 89% fidelity. Coherent control of the SiV^{-} spin with microwave fields is used to demonstrate a spin coherence time T_{2} of 13 ms and a spin relaxation time T_{1} exceeding 1 s at 100 mK. These results establish the SiV^{-} as a promising solid-state candidate for the realization of quantum networks.
Collapse
Affiliation(s)
- D D Sukachev
- Department of Physics, Harvard University, 17 Oxford Street, Cambridge, Massachusetts 02138, USA
| | - A Sipahigil
- Department of Physics, Harvard University, 17 Oxford Street, Cambridge, Massachusetts 02138, USA
| | - C T Nguyen
- Department of Physics, Harvard University, 17 Oxford Street, Cambridge, Massachusetts 02138, USA
| | - M K Bhaskar
- Department of Physics, Harvard University, 17 Oxford Street, Cambridge, Massachusetts 02138, USA
| | - R E Evans
- Department of Physics, Harvard University, 17 Oxford Street, Cambridge, Massachusetts 02138, USA
| | - F Jelezko
- Institute for Quantum Optics, Ulm University and Center for Integrated Quantum Science and Technology, Albert-Einstein-Allee 11, 89081 Ulm, Germany
| | - M D Lukin
- Department of Physics, Harvard University, 17 Oxford Street, Cambridge, Massachusetts 02138, USA
| |
Collapse
|
14
|
Nguyen CT, Pham NM, Do VV, Binns CW, Hoang VM, Dang DA, Lee AH. Soyfood and isoflavone intake and risk of type 2 diabetes in Vietnamese adults. Eur J Clin Nutr 2017; 71:1186-1192. [PMID: 28488690 DOI: 10.1038/ejcn.2017.76] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2016] [Revised: 04/11/2017] [Accepted: 04/13/2017] [Indexed: 12/11/2022]
Abstract
BACKGROUND/OBJECTIVES Animal studies have demonstrated that soy isoflavones exert antidiabetic effects. However, evidence regarding the association between soyfood intake, a unique source of isoflavones, and type 2 diabetes remains inconclusive. This study assessed the relationship between habitual intakes of soyfoods and major isoflavones and risk of type 2 diabetes in Vietnamese adults. SUBJECTS/METHODS A hospital-based case-control study was conducted in Vietnam during 2013-2015. A total of 599 newly diagnosed diabetic cases (age 40-65 years) and 599 hospital-based controls, frequency matched by age and sex, were recruited in Hanoi, capital city of Vietnam. Information on frequency and quantity of soyfood and isoflavone intake, together with demographics, habitual diet and lifestyle characteristics, was obtained from direct interviews using a validated and reliable questionnaire. Unconditional logistic regression analyses were performed to examine the association between soy variables and type 2 diabetes risk. RESULTS Higher intake of total soyfoods was significantly associated with a lower risk of type 2 diabetes; the adjusted odds ratio (OR) for the highest versus the lowest intake was 0.31 (95% confidence interval (CI): 0.21-0.46; P<0.001). An inverse dose-response relationship of similar magnitude was also observed for total isoflavone intake (OR: 0.35; 95% CI: 0.24 to 0.49; P<0.001). In addition, inverse associations of specific soyfoods (soy milk, tofu and mung bean sprout) and major isoflavones (daidzein, genistein and glycitein) with the type 2 diabetes risk were evident. CONCLUSIONS Soyfood and isoflavone intake was associated with a lower type 2 diabetes risk in Vietnamese adults.
Collapse
Affiliation(s)
- C T Nguyen
- School of Public Health, Curtin University, Perth, WA, Australia
- National Institute of Hygiene and Epidemiology, Hanoi, Vietnam
| | - N M Pham
- School of Public Health, Curtin University, Perth, WA, Australia
- Thai Nguyen University of Medicine and Pharmacy, Thai Nguyen, Vietnam
| | - V V Do
- School of Public Health, Curtin University, Perth, WA, Australia
| | - C W Binns
- School of Public Health, Curtin University, Perth, WA, Australia
| | - V M Hoang
- Hanoi University of Public Health, Hanoi, Vietnam
| | - D A Dang
- National Institute of Hygiene and Epidemiology, Hanoi, Vietnam
| | - A H Lee
- School of Public Health, Curtin University, Perth, WA, Australia
| |
Collapse
|
15
|
Bhaskar MK, Sukachev DD, Sipahigil A, Evans RE, Burek MJ, Nguyen CT, Rogers LJ, Siyushev P, Metsch MH, Park H, Jelezko F, Lončar M, Lukin MD. Quantum Nonlinear Optics with a Germanium-Vacancy Color Center in a Nanoscale Diamond Waveguide. Phys Rev Lett 2017. [PMID: 28621982 DOI: 10.1103/physrevlett.118.223603] [Citation(s) in RCA: 62] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
We demonstrate a quantum nanophotonics platform based on germanium-vacancy (GeV) color centers in fiber-coupled diamond nanophotonic waveguides. We show that GeV optical transitions have a high quantum efficiency and are nearly lifetime broadened in such nanophotonic structures. These properties yield an efficient interface between waveguide photons and a single GeV center without the use of a cavity or slow-light waveguide. As a result, a single GeV center reduces waveguide transmission by 18±1% on resonance in a single pass. We use a nanophotonic interferometer to perform homodyne detection of GeV resonance fluorescence. By probing the photon statistics of the output field, we demonstrate that the GeV-waveguide system is nonlinear at the single-photon level.
Collapse
Affiliation(s)
- M K Bhaskar
- Department of Physics, Harvard University, 17 Oxford Street, Cambridge, Massachusetts 02138, USA
| | - D D Sukachev
- Department of Physics, Harvard University, 17 Oxford Street, Cambridge, Massachusetts 02138, USA
- P. N. Lebedev Physical Institute of the RAS, Leninsky Prospekt 53, Moscow 119991, Russia
| | - A Sipahigil
- Department of Physics, Harvard University, 17 Oxford Street, Cambridge, Massachusetts 02138, USA
| | - R E Evans
- Department of Physics, Harvard University, 17 Oxford Street, Cambridge, Massachusetts 02138, USA
| | - M J Burek
- John A. Paulson School of Engineering and Applied Sciences, Harvard University, 29 Oxford Street, Cambridge, Massachusetts 02138, USA
| | - C T Nguyen
- Department of Physics, Harvard University, 17 Oxford Street, Cambridge, Massachusetts 02138, USA
| | - L J Rogers
- Institute for Quantum Optics, University Ulm, Albert-Einstein-Allee 11, 89081 Ulm, Germany
| | - P Siyushev
- Institute for Quantum Optics, University Ulm, Albert-Einstein-Allee 11, 89081 Ulm, Germany
| | - M H Metsch
- Institute for Quantum Optics, University Ulm, Albert-Einstein-Allee 11, 89081 Ulm, Germany
| | - H Park
- Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, Massachusetts 02138, USA
| | - F Jelezko
- Institute for Quantum Optics, University Ulm, Albert-Einstein-Allee 11, 89081 Ulm, Germany
| | - M Lončar
- John A. Paulson School of Engineering and Applied Sciences, Harvard University, 29 Oxford Street, Cambridge, Massachusetts 02138, USA
| | - M D Lukin
- Department of Physics, Harvard University, 17 Oxford Street, Cambridge, Massachusetts 02138, USA
| |
Collapse
|
16
|
Nguyen CT, Pham NM, Nguyen QV, Nguyen VQ, La QN, Lee AH. Menopausal status and type 2 diabetes: a nationwide epidemiological survey in Vietnam. Public Health 2016; 138:168-9. [PMID: 27193910 DOI: 10.1016/j.puhe.2016.04.010] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2016] [Revised: 04/13/2016] [Accepted: 04/14/2016] [Indexed: 11/28/2022]
Affiliation(s)
- C T Nguyen
- Department of Epidemiology, National Institute of Hygiene and Epidemiology, Vietnam.
| | - N M Pham
- Faculty of Public Health, Thai Nguyen University of Medicine and Pharmacy, Vietnam; School of Public Health, Curtin University, Perth, Australia.
| | - Q V Nguyen
- National Hospital of Endocrinology, Vietnam.
| | - V Q Nguyen
- National Hospital of Endocrinology, Vietnam.
| | - Q N La
- Hanoi School of Public Health, Vietnam.
| | - A H Lee
- School of Public Health, Curtin University, Perth, Australia.
| |
Collapse
|
17
|
Ahn AN, Kang JK, Quitt MA, Davidson BC, Nguyen CT. Variability of neural activation during walking in humans: short heels and big calves. Biol Lett 2011; 7:539-42. [PMID: 21288939 DOI: 10.1098/rsbl.2010.1169] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
People come in different shapes and sizes. In particular, calf muscle size in humans varies considerably. One possible cause for the different shapes of calf muscles is the inherent difference in neural signals sent to these muscles during walking. In sedentary adults, the variability in neural control of the calf muscles was examined with muscle size, walking kinematics and limb morphometrics. Half the subjects walked while activating their medial gastrocnemius (MG) muscles more strongly than their lateral gastrocnemius (LG) muscles during most walking speeds ('MG-biased'). The other subjects walked while activating their MG and LG muscles nearly equally ('unbiased'). Those who walked with an MG-biased recruitment pattern also had thicker MG muscles and shorter heel lengths, or MG muscle moment arms, than unbiased walkers, but were similar in height, weight, lower limb length, foot length, and exhibited similar walking kinematics. The relatively less plastic skeletal system may drive calf muscle size and motor recruitment patterns of walking in humans.
Collapse
Affiliation(s)
- A N Ahn
- Department of Biology, Harvey Mudd College, 301 Platt Boulevard, Claremont, CA 91711, USA.
| | | | | | | | | |
Collapse
|
18
|
Nguyen CT, Gao T, Hernandez AV, Jones JS. Can residents perform transrectal ultrasound-guided prostate biopsy with patient comfort comparable to biopsy performed by attending staff urologists? Prostate Cancer Prostatic Dis 2009; 13:52-7. [PMID: 19770843 DOI: 10.1038/pcan.2009.36] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Transrectal ultrasound (TRUS)-guided prostate biopsy is a critical diagnostic tool in urology. Residents require adequate training but resident education could have a deleterious effect on patient comfort and morbidity. We compared pain associated with prostate biopsy when performed by staff versus resident urologists in order to determine the impact of resident training. Male patients scheduled to undergo prostate biopsy were assigned to either a staff urologist or a resident as the primary surgeon. All residents were directly assisted by the staff surgeon. The patients were given a visual analogue scale (VAS; 0-100 mm) and were asked to assess the pain associated with each component of prostate biopsy, including probe insertion, anesthetic injection and the biopsies themselves. The mean VAS scores for probe insertion, anesthetic injection and biopsies were 31.0, 30.4 and 30.1, respectively, for patients in the staff cohort and 37.1, 28.9 and 33.6, respectively, for those in the resident cohort. There was a statistically significant difference between staff and resident VAS scores, marked by a higher odds of greater pain with ultrasound probe placement (odds ratio (OR)=1.48, P=0.012) and the biopsies themselves (OR=1.52, P=0.01) in the resident cohort. TRUS biopsy can be performed by adequately trained and supervised resident urologists of all levels, but there is the potential for increased patient pain, particularly with ultrasonic probe insertion and obtaining core biopsies. However, the absolute magnitude of the differences in pain scores between residents and staff was small and may not be clinically meaningful. Such data indicate that urological resident training can be accomplished without compromising patient care and comfort.
Collapse
Affiliation(s)
- C T Nguyen
- Department of Regional Urology, Glickman Urological & Kidney Institute, Cleveland Clinic Foundation, Cleveland, OH 44195, USA
| | | | | | | |
Collapse
|
19
|
Abstract
A non-destructive method for assaying transuranic neutron sources was developed, using a combination of gamma-spectrometry and neutron correlation technique. Source strength or actinide content of a number of PuBe, AmBe, AmLi, (244)Cm, and (252)Cf sources was assessed, both as a safety issue and with respect to combating illicit trafficking. A passive neutron coincidence collar was designed with (3)He counters embedded in a polyethylene moderator (lined with Cd) surrounding the sources to be measured. The electronics consist of independent channels of pulse amplifiers and discriminators as well as a shift register for coincidence counting. The neutron output of the sources was determined by gross neutron counting, and the actinide content was found out by adopting specific spontaneous fission and (alpha,n) reaction yields of individual isotopes from the literature. Identification of an unknown source type and constituents can be made by gamma-spectrometry. The coincidences are due to spontaneous fission in the case of Cm and Cf sources, while they are mostly due to neutron-induced fission of the Pu isotopes (i.e. self-multiplication) and the (9)Be(n,2n)(8)Be reaction in Be-containing sources. Recording coincidence rate offers a potential for calibration, exploiting a correlation between the Pu amount and the coincidence-to-total ratio. The method and the equipment were tested in an in-field demonstration exercise, with participation of national public authorities and foreign observers. Seizure of the illicit transport of a PuBe source was simulated in the exercise, and the Pu content of the source was determined. It is expected that the method could be used for identification and assay of illicit, found, or not documented neutron sources.
Collapse
Affiliation(s)
- L Lakosi
- Institute of Isotopes, Chemical Research Centre of the Hungarian Academy of Sciences, P.O. Box 77, H-1525 Budapest, Hungary.
| | | | | |
Collapse
|
20
|
Nguyen CT, Gonzales FA, Jones PA. Altered chromatin structure associated with methylation-induced gene silencing in cancer cells: correlation of accessibility, methylation, MeCP2 binding and acetylation. Nucleic Acids Res 2001; 29:4598-606. [PMID: 11713309 PMCID: PMC92514 DOI: 10.1093/nar/29.22.4598] [Citation(s) in RCA: 191] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Silencing of tumor-suppressor genes by hypermethylation of promoter CpG islands is well documented in human cancer and may be mediated by methyl-CpG-binding proteins, like MeCP2, that are associated in vivo with chromatin modifiers and transcriptional repressors. However, the exact dynamic between methylation and chromatin structure in the regulation of gene expression is not well understood. In this study, we have analyzed the methylation status and chromatin structure of three CpG islands in the p14(ARF)/p16(INK4A) locus in a series of normal and cancer cell lines using methylation-sensitive digestion, MspI accessibility in intact nuclei and chromatin immunoprecipitation (ChIP) assays. We demonstrate the existence of an altered chromatin structure associated with the silencing of tumor-suppressor genes in human cancer cell lines involving CpG island methylation, chromatin condensation, histone deacetylation and MeCP2 binding. The data showed that MeCP2 could bind to methylated CpG islands in both promoters and exons; MeCP2 does not interfere with transcription when bound at an exon, suggesting a more generalized role for the protein beyond transcriptional repression. In the absence of methylation, it is demonstrated that CpG islands located in promoters versus exons display marked differences in the levels of acetylation of associated histone H3, suggesting that chromatin remodeling can be achieved by methylation-independent processes and perhaps explaining why non-promoter CpG islands are more susceptible to de novo methylation than promoter islands.
Collapse
Affiliation(s)
- C T Nguyen
- Department of Biochemistry and Molecular Biology, USC/Norris Comprehensive Cancer Center, Keck School of Medicine of the University of Southern California, 1441 Eastlake Avenue, Room 8302L, Los Angeles, CA 90089-9181, USA
| | | | | |
Collapse
|
21
|
Nguyen CT, Hall CS, Scott MJ, Zhu Q, Marsh J, Wickline SA. Age-related alterations of cardiac tissue microstructure and material properties in Fischer 344 rats. Ultrasound Med Biol 2001; 27:611-619. [PMID: 11397525 DOI: 10.1016/s0301-5629(01)00343-x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The cardiac aging process is accompanied by global mechanical dysfunction that reflects increased myocardial stiffness. Accordingly, age-related changes in microscopic material properties of myocardium were delineated with high-frequency ultrasound (US) (30 to 44 MHz) tissue characterization methods for aging Fischer 344 rats at 6 (adult), 18 (aged), and 24 (senescent) months of age. The excised lateral wall of the left ventricle of rats (n = 10 per group) was insonified with a 50-MHz acoustic microscope for determination of integrated backscatter, backscatter coefficient and attenuation coefficient. Histological and biochemical analyses for collagen content and cardiac myocyte diameter were performed. Collagen concentration increased progressively with age, with the greatest increments occurring from 6 to 18 months (38.0 +/- 6.3 to 53.0 +/- 7.1 mg/g dry wt), and leveling off at 24 months (60.0 +/- 7.4 mg/g dry wt). Tissue microscopic material properties also changed progressively from 6 to 24 months of age, as determined by US methods: integrated backscatter increased (-44.7 +/- 1.8 vs. -40.8 +/- 1.9 dB, p < 0.05), attenuation increased (47.1 +/- 5.9 to 65.3 +/- 7.8 dB/cm, p < 0.05), and the backscatter coefficient increased (0.73 +/- 0.16 x 10(-5) to 3.76 +/- 1.6 x 10(-5) cm(-1), p < 0.05), from 6 to 24 months of age in each case. Age-related alterations in indices of cardiac microscopic material properties were closely correlated with the changes in cardiac microstructure. Ultrasonic tissue characterization may prove to be a sensitive tool to monitor changes in the cardiac microstructure, such as increased collagen deposition, that occur within age-related diastolic dysfunction.
Collapse
Affiliation(s)
- C T Nguyen
- Cardiovascular Division, Barnes-Jewish Hospital at Washington University School of Medicine, St. Louis, MO 63110, USA
| | | | | | | | | | | |
Collapse
|
22
|
Abstract
BACKGROUND Downregulation of genes which negatively control cell cycle progression represents a possible mechanism for prostate tumorigenesis. We examined the expression levels of the p16, p15, p14, and retinoblastoma-susceptibility (RB) genes in primary prostate cancers and human prostate cancer cell lines, and correlated this with the DNA methylation levels of two loci in p16. METHODS The mRNA levels of p16, p15, and p14 were examined by reverse transcriptase-PCR (RT-PCR). DNA methylation of the p16 5' CpG island was determined by bisulfite genomic sequencing, while methylation of exon 2 shared by the p16 and p14 genes was measured by a quantitative bisulfite-based technique, methylation-sensitive single-nucleotide primer extension (Ms-SNuPE). RB protein levels were assessed by immunohistochemical staining of histologic sections of normal and tumor prostate tissues, using a monoclonal antibody (mAB). RESULTS Overexpression of p16 mRNA was found in 6/9 (67) of prostate tumors compared to the adjacent normal prostate, whereas elevated p14 and p15 levels were only observed in 2/9 (22) and 1/6 (17) of prostate cases, respectively. There was no statistically significant association of grade (P = 0.18) and stage (P = 1.00) of prostate cancer to the elevated p16 levels in the tumors. The p16 5' CpG island was completely unmethylated in these tissues. In contrast, exon 2 of p16/p14 was methylated in both the tumor and normal adjacent prostates, and was increased in 8/11 (73) of tumors relative to normal tissues. There was no association between p16 overexpression and increased p16/p14 exon 2 methylation in these tumors (P = 1.00). Diminished RB levels in prostate tumors that had upregulated p16 mRNA were found, although absent RB was also detected in tumors without elevated p16 levels. The expression levels of the two genes, RB and p16, were not correlated statistically (P = 0.16). CONCLUSIONS Our studies show that although the levels of the cell cycle regulators p16, p15, p14, and Rb are altered in prostate cancers, there is no apparent correlation to grade, stage, or any pattern of regulation between the related genes. Exon 2 of p16/p14 is methylated in a majority of prostate tumors compared to the unmethylated upstream 5' region, and may be a potential tumor marker for human prostate cancer.
Collapse
Affiliation(s)
- T T Nguyen
- Department of Biochemistry and Molecular Biology, USC/Norris Comprehensive Cancer Center, University of Southern California School of Medicine, Los Angeles, CA 90089-9181, USA
| | | | | | | | | | | |
Collapse
|
23
|
Hall CS, Nguyen CT, Scott MJ, Lanza GM, Wickline SA. Delineation of the extracellular determinants of ultrasonic scattering from elastic arteries. Ultrasound Med Biol 2000; 26:613-620. [PMID: 10856624 DOI: 10.1016/s0301-5629(99)00165-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Elastic arteries consist of three primary components: elastin fibers, extracellular collagen matrix and smooth muscle cells. However, the relative contribution of elastin and collagen fibers to overall ultrasonic scattering from an intact arterial wall is poorly understood. To define the principal source of extracellular scattering from the medial layer of elastic arteries, canine ascending aortas (n = 10) were excised, fixed and sectioned for insonification. Subsequently, aortic specimens were restudied after treatment to dissolve all tissue components except extracellular collagen matrix (n = 5) and elastin fibers (n = 5). Histological staining revealed very few elastin fibers and sparse intact collagen in collagen-isolated and elastin-isolated tissues, respectively. Integrated backscatter, attenuation and backscatter coefficients differentiated these two treated tissues. The backscatter coefficient for elastin-isolated tissue demonstrated a fivefold increase over collagen-isolated tissue, suggesting that elastin fibers represent a primary scattering component within elastic arteries, and the collagen fibers may provide a secondary component of scattering.
Collapse
Affiliation(s)
- C S Hall
- Washington University School of Medicine, and Barnes-Jewish Hospital, St. Louis, MO 63110, USA.
| | | | | | | | | |
Collapse
|
24
|
Abstract
BACKGROUND Endoscopic placement of biliary stents is an effective initial treatment for jaundice and cholangitis caused by common bile duct (CBD) strictures secondary to chronic pancreatitis; however, the role of endoscopic treatment for long-term management of these strictures is less clear. In 1992, we designed a protocol of balloon dilatation and stenting for > or =12 months. This study evaluates endoscopic therapy as a definitive long-term treatment for these strictures. We have treated 25 patients with this protocol. METHODS All patients had an endoscopic sphincterotomy, balloon dilatation of the stricture, and then placement of a polyethylene stent (7-11.5 F). Stents were exchanged at 3-4-month intervals to avoid the complications of clogging and cholangitis. We were particularly interested in how many patients would achieve resolution of the stricture and tolerate removal of the stent. RESULTS The length of the CBD strictures ranged from 8 to 40 mm. Within days of stenting, all patients achieved relief of jaundice and cholestasis. Complications consisted of six episodes of cholangitis and nine episodes of pancreatitis. There were no deaths. Twenty of the 25 patients are now stent-free after an average stenting period of 13 months (range, 3-28). To date, there has been no recurrence of stricture, for a mean of 32 months. Three patients still have stents in place, and two patients required operation--one for persistent stricture and recurrent cholangitis after 8 months of stenting, and one for a mass in the head of the pancreas that was thought to be cancer. CONCLUSIONS Our results indicate that these strictures will respond and dilate after a course of stenting in 80% of patients, with an acceptable morbidity. Although these are medium-term results at 32 months, we would expect most recurrences within the 1st year following stent removal. In some cases, stenting is necessary for >12 months. Thus, the data suggest that endoscopic stenting provides definitive treatment in most patients with CBD stricture due to chronic pancreatitis and may be considered a viable alternative to standard surgical bypass.
Collapse
Affiliation(s)
- G C Vitale
- Department of Surgery, University of Louisville School of Medicine, KY 40292, USA
| | | | | | | | | |
Collapse
|
25
|
Lavigne F, Nguyen CT, Cameron L, Hamid Q, Renzi PM. Prognosis and prediction of response to surgery in allergic patients with chronic sinusitis. J Allergy Clin Immunol 2000; 105:746-51. [PMID: 10756225 DOI: 10.1067/mai.2000.105218] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
BACKGROUND Chronic rhinosinusitis (CRS) occurs frequently in patients with atopy, but little is known of the prognosis after surgery and of factors that may predict a poor outcome. OBJECTIVE Our purpose was to assess the long-term prognosis in atopic patients with CRS who undergo surgery and whether certain immune markers could predict a worse prognosis in this setting. METHODS Fifteen patients with diffuse involvement of the sinuses on computed tomographic (CT) scan but without nasal polyposis underwent ethmoidectomy with middle meatotomy for CRS when it was clinically indicated. All patients had a biopsy of the inferior turbinate and of the most inflamed areas of the maxillary and ethmoid sinuses at the time of surgery. Follow-up was performed by video endoscopy and by assessment of 2 chronic sinusitis questionnaires at 0, 6, and 24 months postoperatively. The number of lymphocyte subsets (CD3, CD4, CD8), mast cells and eosinophils, and cells expressing IL-4 and IL-5 messenger RNA (mRNA) in all 3 biopsy sites at the time of surgery were compared with the clinical response after surgery. RESULTS Seven patients had persistent improvement after surgery, with a decrease in pain, rhinorrhea, or nasal obstruction and a decrease in the need for medication. Eight patients were unchanged or worsened after surgery with disabling rhinorrhea and repeated sinusitis. We found no difference in the number of inflammatory cells, lymphocyte subsets, or IL-4 mRNA-positive cells in the sinus mucosa between responders and nonresponders. However, an increased number of cells expressing IL-5 mRNA was found in the ethmoid sinus at the time of surgery in patients who did not respond to the surgical intervention (P =.007). CONCLUSION More than 50% of patients with perennial rhinitis and CRS do not improve after surgery, a response that may be predicted by more cells expressing IL-5 mRNA in the ethmoid sinuses. The increased number of cells expressing IL-5 mRNA may have the potential to be used as a marker for prediction of the response to surgery. The worsening of symptoms in some patients with CRS after sinus surgery could be a result of the disturbance of the anatomy of the sinuses and exposure to the environmental allergens.
Collapse
Affiliation(s)
- F Lavigne
- Centre Hospitalier de l'Universitaire de Montréal, Notre-Dame Hospital, University of Montreal, Montreal, Quebec, Canada
| | | | | | | | | |
Collapse
|
26
|
Abstract
BACKGROUND Primary melanocytic schwannoma arising from the cervical sympathetic chain is a rare pigmented nerve sheath tumor. Two cases are presented from an academic medical center. Patients and Methods Patients were initially seen with an enlarging neck mass associated with sympathetic nervous system dysfunction. Radiography demonstrated a mass located posterior to the carotid sheath. Primary therapy consisted of surgical excision and postoperative radiation therapy. RESULTS The tumors were found to be melanocytic schwannomas arising from the cervical sympathetic chain. The pathologic characteristics of this neoplasm are reviewed. One patient remained disease free for 12 years after treatment, whereas 1 patient died as a result of local recurrence and distant metastases. CONCLUSIONS Melanocytic schwannoma of the cervical sympathetic chain is a rare nerve sheath tumor of the head and neck that may be misdiagnosed as malignant melanoma. The clinical behavior of this neoplasm is variable. Preoperative neurologic findings, anatomic location, electron microscopy, and immunohistochemistry findings help to establish the diagnosis, and electron microscopy may have a role in distinguishing between benign and malignant lesions. Complete surgical excision is the treatment of choice.
Collapse
Affiliation(s)
- C T Nguyen
- Division of Head and Neck Surgery, University of California Los Angeles School of Medicine, Los Angeles, California, USA
| | | | | | | | | |
Collapse
|
27
|
Vitale GC, Reed DN, Nguyen CT, Lawhon JC, Larson GM. Endoscopic treatment of distal bile duct stricture from chronic pancreatitis. Surg Endosc 2000; 14:227-31. [PMID: 10741437] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
BACKGROUND Endoscopic placement of biliary stents is an effective initial treatment for jaundice and cholangitis caused by common bile duct (CBD) strictures secondary to chronic pancreatitis; however, the role of endoscopic treatment for long-term management of these strictures is less clear. In 1992, we designed a protocol of balloon dilatation and stenting for > or =12 months. This study evaluates endoscopic therapy as a definitive long-term treatment for these strictures. We have treated 25 patients with this protocol. METHODS All patients had an endoscopic sphincterotomy, balloon dilatation of the stricture, and then placement of a polyethylene stent (7-11.5 F). Stents were exchanged at 3-4-month intervals to avoid the complications of clogging and cholangitis. We were particularly interested in how many patients would achieve resolution of the stricture and tolerate removal of the stent. RESULTS The length of the CBD strictures ranged from 8 to 40 mm. Within days of stenting, all patients achieved relief of jaundice and cholestasis. Complications consisted of six episodes of cholangitis and nine episodes of pancreatitis. There were no deaths. Twenty of the 25 patients are now stent-free after an average stenting period of 13 months (range, 3-28). To date, there has been no recurrence of stricture, for a mean of 32 months. Three patients still have stents in place, and two patients required operation--one for persistent stricture and recurrent cholangitis after 8 months of stenting, and one for a mass in the head of the pancreas that was thought to be cancer. CONCLUSIONS Our results indicate that these strictures will respond and dilate after a course of stenting in 80% of patients, with an acceptable morbidity. Although these are medium-term results at 32 months, we would expect most recurrences within the 1st year following stent removal. In some cases, stenting is necessary for >12 months. Thus, the data suggest that endoscopic stenting provides definitive treatment in most patients with CBD stricture due to chronic pancreatitis and may be considered a viable alternative to standard surgical bypass.
Collapse
Affiliation(s)
- G C Vitale
- Department of Surgery, University of Louisville School of Medicine, KY 40292, USA
| | | | | | | | | |
Collapse
|
28
|
Bender CM, Gonzalgo ML, Gonzales FA, Nguyen CT, Robertson KD, Jones PA. Roles of cell division and gene transcription in the methylation of CpG islands. Mol Cell Biol 1999; 19:6690-8. [PMID: 10490608 PMCID: PMC84656 DOI: 10.1128/mcb.19.10.6690] [Citation(s) in RCA: 103] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/1999] [Accepted: 07/07/1999] [Indexed: 11/20/2022] Open
Abstract
De novo methylation of CpG islands within the promoters of eukaryotic genes is often associated with their transcriptional repression, yet the methylation of CpG islands located downstream of promoters does not block transcription. We investigated the kinetics of mRNA induction, demethylation, and remethylation of the p16 promoter and second-exon CpG islands in T24 cells after 5-aza-2'-deoxycytidine (5-Aza-CdR) treatment to explore the relationship between CpG island methylation and gene transcription. The rates of remethylation of both CpG islands were associated with time but not with the rate of cell division, and remethylation of the p16 exon 2 CpG island occurred at a higher rate than that of the p16 promoter. We also examined the relationship between the remethylation of coding sequence CpG islands and gene transcription. The kinetics of remethylation of the p16 exon 2, PAX-6 exon 5, c-ABL exon 11, and MYF-3 exon 3 loci were examined following 5-Aza-CdR treatment because these genes contain exonic CpG islands which are hypermethylated in T24 cells. Remethylation occurred most rapidly in the p16, PAX-6, and c-ABL genes, shown to be transcribed prior to drug treatment. These regions also exhibited higher levels of remethylation in single-cell clones and subclones derived from 5-Aza-CdR-treated T24 cells. Our data suggest that de novo methylation is not restricted to the S phase of the cell cycle and that transcription through CpG islands does not inhibit their remethylation.
Collapse
Affiliation(s)
- C M Bender
- Urologic Research Laboratory, USC/Norris Comprehensive Cancer Center, University of Southern California School of Medicine, Los Angeles, California 90089-9181, USA
| | | | | | | | | | | |
Collapse
|
29
|
Abstract
When stenosis of the larynx and trachea involves loss to anterior support, this is usually corrected by an autograft of costochondral cartilage or of hyoid bone anchored with suture material. This paper describes an alternative technique employing a Vitallium alloy miniplate placed anterior to the airway as a means for providing support. This is placed over a fascial or auricular cartilage graft. Together, they provide a smooth scaffold for mucosal migration. Thirteen patients were treated at Indiana University Medical Center between 1991 and 1993 by means of this technique. Ten of the 13 patients (77%) achieved an adequate airway to allow decannulation. There have been no significant complications related to the use of the miniplate, and specifically, there have been no instances of infection or extrusion. It has been unnecessary to remove any of the miniplates. The Vitallium alloy miniplate offers unique advantages in laryngotracheal reconstruction in that it not only accurately approximates tissues, but it also provides external support to the airway.
Collapse
Affiliation(s)
- E C Weisberger
- Department of Otolaryngology-Head and Neck Surgery, Indiana University Medical Center, Indianapolis, USA
| | | |
Collapse
|
30
|
Chu AJ, Nguyen CT, Moore J. Differential effects of unsaturated fatty acids on phospholipid synthesis in human leukemia monocytic U937 cells. Cell Biochem Funct 1993; 11:201-9. [PMID: 8403234 DOI: 10.1002/cbf.290110308] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
The biosynthesis of phosphatidylcholine (PC) and phosphatidylethanolamine (PE) in monocyte-like leukemia U937 cells was monitored by adding [3H]choline, [14C]ethanolamine or [14C]glycerol to the culture media; incorporation into phospholipid (PL) increased with time. The effect of unsaturated fatty acids (UFA) on PC and PE synthesis was investigated by pretreating U937 cells for 72h with 10 microM 18:1 (n - 9), 18:2 (n - 6), 18:3 (n - 3), 20:4 (n - 6) and 20:5 (n - 3). The UFA caused no alteration in cell growth, as evidenced by light microscopy and the incorporation of [3H]thymidine and [3H]leucine. Total cellular uptake of radioactive precursors remained unaffected by all the treatments. Pretreatment with 20:5 resulted in approximately 25 per cent reduction in the incorporation of [3H]choline into PL, while no significant effect was detected with the other UFAs. 18:3, 20:4 and 20:5 depressed the incorporation of [14C]ethanolamine into PL by 34 per cent, 28 per cent and 49 per cent respectively. However, there was no redistribution of label with any of the treatments. 18:3, 20:4 and 20:5 also antagonized the stimulatory effect of endotoxin (LPS) on PC and PE synthesis. In addition, the incorporation from [14C]glycerol into PC and PE was reduced by 18:3, 20:4 and 20:5. Although the PL composition of the cells remained essentially unaffected, our study shows that chronic treatment of U937 cells with n - 3 PUFA (20:5) depressed PC and PE synthesis, and 18:3 and 20:4 also caused inhibition of PE synthesis.
Collapse
Affiliation(s)
- A J Chu
- Research Division, Miami Heart Institute, Miami Beach, FL 33140-2999
| | | | | |
Collapse
|
31
|
Chu AJ, Nguyen CT. Ethanol inhibits phosphatidylcholine and phosphatidylethanolamine biosynthesis in human leukemic monocyte-like U937 cells. Cell Biochem Funct 1993; 11:107-17. [PMID: 8324879 DOI: 10.1002/cbf.290110206] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
The effect of ethanol (ETOH) on the incorporation of [14C]oleic acid (18:1) into lipid in human monocyte-like U937 cells was investigated. With increasing time of exposure to ETOH, the percentage of the label distributed into neutral lipid (NL) declined from 35 per cent (3 h) to 10 per cent (24 h) accompanied by increased incorporation into phospholipid (PL). [14C] 18:1 was preferentially incorporated into triglyceride (TG) and phosphatidylcholine (PC), comprising over 65 per cent and 50 per cent of the label associated with NL and PL, respectively. Low concentrations of ETOH (< or = 1.0 per cent; v/v) had no effect. At concentrations greater than 1.5 per cent, there was enhanced incorporation into TG and diacylglycerol (DAG) in a 24-h incubation period, while at 16 h the label in phosphatidylethanolamine (PE) was decreased. The effect of ETOH on the CDP-choline or ethanolamine pathway was examined by monitoring the incorporation of [3H]choline or [14C]ethanolamine into PC or PE, respectively. At low concentrations ETOH had no effect on either choline uptake or the incorporation into PC. Higher concentrations (> or = 1.5 per cent) for 3 and 6 h resulted in a slightly decreased choline uptake, and the reduction (40-50 per cent) of incorporation into PC suggests that the CDP-choline pathway was inhibited. There was a similar inhibition of the incorporation of [14C]ethanolamine into PE. When the cells were incubated for 3 h in the presence of 2 per cent ETOH and with labelled 18:1 and PL-base, the ratios of incorporation (base/18:1) into PC and PE fractions decreased, indicating that the major inhibition lay in blockage of the availability of the base moiety for PL formation. Analysis of the distribution of the label into metabolites revealed that ETOH inhibited the conversion of [14C]ethanolamine into [14C]phosphorylethanolamine. The reduction in incorporation was not due to the enhanced breakdown of base-labelled PL. Our results indicate that ETOH has an inhibitory effect on the CDP-choline or ethanolamine pathway.
Collapse
Affiliation(s)
- A J Chu
- Miami Heart Institute, Miami Beach, FL 33140-2999
| | | |
Collapse
|
32
|
Abstract
The regional blood flow (BF) response to submaximal exercise was determined for sedentary and trained myocardial infarcted (MI) rats. Training consisted of treadmill running (10% grade, 30 m/min) for 1 h/day, 5 days/wk for 12-14 wk and produced decreases in resting heart rate and increases in maximal O2 uptake and endurance capacity. BF determined at 2 and 6 min of exercise (via radiolabeled microspheres) demonstrated that trained rats maintained greater BF to organs found in the abdominal region when compared with their sedentary counterparts. BF to the total hindlimb musculature at 2 min of exercise was greater in sedentary rats when compared with their trained counterparts and was the consequence of greater BF to 10 of the 27 muscle or muscle parts investigated. At 6 min of exercise, BF to the total hindlimb musculature was similar between trained and sedentary rats, as BF in 9 of 27 muscles or muscle parts investigated decreased from 2 to 6 min of exercise for the sedentary group. In general, the BF patterns within and among the individual muscles of the hindlimb were different between the two groups. Trained rats tended to maintain greater BF to the predominantly red muscles, whereas the sedentary rats maintained greater BF to the predominantly white muscles at 6 min of exercise. In conclusion, the training-induced changes in BF found in this study are similar to those found previously for normal rats, and they demonstrate that endurance training produces changes in the regional distribution of BF during exercise in MI rats.
Collapse
Affiliation(s)
- T I Musch
- Department of Medicine, Pennsylvania State University, Hershey 17033
| | | | | | | |
Collapse
|
33
|
Suzuki T, Nguyen CT, Nantel F, Bonin H, Valiquette M, Frielle T, Bouvier M. Distinct regulation of beta 1- and beta 2-adrenergic receptors in Chinese hamster fibroblasts. Mol Pharmacol 1992; 41:542-8. [PMID: 1347641] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/25/2023] Open
Abstract
The agonist-induced reduction of beta-adrenergic receptor (beta AR) cell surface density is a well documented phenomenon. The mechanisms responsible for this regulation have been well characterized for the beta 2AR. They include a rapid sequestration of the receptor away from the cell surface in a vesicular compartment and a longer term down-regulation of the total beta 2AR number. In contrast, very little is known about the cell surface regulation of the beta 1AR. In the present study, we have compared the agonist-mediated regulation of beta 1- and beta 2AR in Chinese hamster fibroblasts transfected with the cDNA encoding either beta AR subtype. Cells expressing similar numbers of the two beta AR subtypes were selected for the study. The expressed receptors exhibit typical beta 1- and beta 2AR selectivity for agonists and antagonists, as assessed by radioligand binding. Both receptors were found to be positively coupled to the adenylyl cyclase stimulatory pathway, but marked differences in the receptor regulation profiles were observed. Treatment of the cells expressing the beta 2AR with the agonist isoproterenol leads to a rapid sequestration of greater than 30% of the receptors away from the cell surface into a light vesicular fraction, where they are inaccessible to the hydrophilic ligand CGP-12177. In contrast, virtually no agonist-induced sequestration is observed in the cells expressing the beta 1AR. Longer exposure of the cells to isoproterenol leads to a time-dependent reduction in the total number of beta ARs in both beta 1- and beta 2AR-expressing cell lines. However, this down-regulation is significantly slower in the cells expressing the beta 1AR. In fact, no appreciable down-regulation of the beta 1ARs is detected in the first 4 hr of agonist treatment, compared with a down-regulation of greater than 50% of the beta 2ARs for the same period. After a 24-hr treatment with isoproterenol, less than 20% of the original number of beta 2ARs remain, whereas 60% of the beta 1ARs are still present after the same treatment. These results, therefore, suggest that, when expressed in an identical cell line, beta 1AR and beta 2AR follow distinct patterns of regulation. In fact, both agonist-induced sequestration and down-regulation are considerably blunted for the beta 1AR, compared with the beta 2AR.
Collapse
Affiliation(s)
- T Suzuki
- Department of Biochemistry, Université de Montréal, Canada
| | | | | | | | | | | | | |
Collapse
|