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Pham N, Hill V, Rauschecker A, Lui Y, Niogi S, Fillipi CG, Chang P, Zaharchuk G, Wintermark M. Critical Appraisal of Artificial Intelligence-Enabled Imaging Tools Using the Levels of Evidence System. AJNR Am J Neuroradiol 2023; 44:E21-E28. [PMID: 37080722 PMCID: PMC10171388 DOI: 10.3174/ajnr.a7850] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [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: 12/16/2022] [Accepted: 03/16/2023] [Indexed: 04/22/2023]
Abstract
Clinical adoption of an artificial intelligence-enabled imaging tool requires critical appraisal of its life cycle from development to implementation by using a systematic, standardized, and objective approach that can verify both its technical and clinical efficacy. Toward this concerted effort, the ASFNR/ASNR Artificial Intelligence Workshop Technology Working Group is proposing a hierarchal evaluation system based on the quality, type, and amount of scientific evidence that the artificial intelligence-enabled tool can demonstrate for each component of its life cycle. The current proposal is modeled after the levels of evidence in medicine, with the uppermost level of the hierarchy showing the strongest evidence for potential impact on patient care and health care outcomes. The intended goal of establishing an evidence-based evaluation system is to encourage transparency, foster an understanding of the creation of artificial intelligence tools and the artificial intelligence decision-making process, and to report the relevant data on the efficacy of artificial intelligence tools that are developed. The proposed system is an essential step in working toward a more formalized, clinically validated, and regulated framework for the safe and effective deployment of artificial intelligence imaging applications that will be used in clinical practice.
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Affiliation(s)
- N Pham
- From the Department of Radiology (N.P., G.Z.), Stanford School of Medicine, Palo Alto, California
| | - V Hill
- Department of Radiology (V.H.), Northwestern University Feinberg School of Medicine, Chicago, Illinois
| | - A Rauschecker
- Department of Radiology (A.R.), University of California, San Francisco, San Francisco, California
| | - Y Lui
- Department of Radiology (Y.L.), NYU Grossman School of Medicine, New York, New York
| | - S Niogi
- Department of Radiology (S.N.), Weill Cornell Medicine, New York, New York
| | - C G Fillipi
- Department of Radiology (C.G.F.), Tufts University School of Medicine, Boston, Massachusetts
| | - P Chang
- Department of Radiology (P.C.), University of California, Irvine, Irvine, California
| | - G Zaharchuk
- From the Department of Radiology (N.P., G.Z.), Stanford School of Medicine, Palo Alto, California
| | - M Wintermark
- Department of Neuroradiology (M.W.), The University of Texas MD Anderson Cancer Center, Houston, Texas
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Kihira S, Derakhshani A, Leung M, Mahmoudi K, Bauer A, Zhang H, Polson J, Arnold C, Tsankova NM, Hormigo A, Salehi B, Pham N, Ellingson BM, Cloughesy TF, Nael K. Multi-Parametric Radiomic Model to Predict 1p/19q Co-Deletion in Patients with IDH-1 Mutant Glioma: Added Value to the T2-FLAIR Mismatch Sign. Cancers (Basel) 2023; 15:cancers15041037. [PMID: 36831380 PMCID: PMC9954034 DOI: 10.3390/cancers15041037] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2022] [Revised: 01/28/2023] [Accepted: 01/28/2023] [Indexed: 02/10/2023] Open
Abstract
PURPOSE The T2-FLAIR mismatch sign has shown promise in determining IDH mutant 1p/19q non-co-deleted gliomas with a high specificity and modest sensitivity. To develop a multi-parametric radiomic model using MRI to predict 1p/19q co-deletion status in patients with newly diagnosed IDH1 mutant glioma and to perform a comparative analysis to T2-FLAIR mismatch sign+. METHODS In this retrospective study, patients with diagnosis of IDH1 mutant gliomas with known 1p/19q status who had preoperative MRI were included. T2-FLAIR mismatch was evaluated independently by two board-certified neuroradiologists. Texture features were extracted from glioma segmentation of FLAIR images. eXtremeGradient Boosting (XGboost) classifiers were used for model development. Leave-one-out-cross-validation (LOOCV) and external validation performances were reported for both the training and external validation sets. RESULTS A total of 103 patients were included for model development and 18 patients for external testing validation. The diagnostic performance (sensitivity/specificity/accuracy) in the determination of the 1p/19q co-deletion status was 59%/83%/67% (training) and 62.5%/70.0%/66.3% (testing) for the T2-FLAIR mismatch sign. This was significantly improved (p = 0.04) using the radiomics model to 77.9%/82.8%/80.3% (training) and 87.5%/89.9%/88.8% (testing), respectively. The addition of radiomics as a computer-assisted tool resulted in significant (p = 0.02) improvement in the performance of the neuroradiologist with 13 additional corrected cases in comparison to just using the T2-FLAIR mismatch sign. CONCLUSION The proposed radiomic model provides much needed sensitivity to the highly specific T2-FLAIR mismatch sign in the determination of the 1p/19q non-co-deletion status and improves the overall diagnostic performance of neuroradiologists when used as an assistive tool.
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Affiliation(s)
- Shingo Kihira
- Department of Radiological Sciences, David Geffen School of Medicine at University of California Los Angeles, 757 Westwood Plaza, Suite 1621, Los Angeles, CA 90095, USA
| | - Ahrya Derakhshani
- Department of Radiological Sciences, David Geffen School of Medicine at University of California Los Angeles, 757 Westwood Plaza, Suite 1621, Los Angeles, CA 90095, USA
| | - Michael Leung
- Department of Radiological Sciences, David Geffen School of Medicine at University of California Los Angeles, 757 Westwood Plaza, Suite 1621, Los Angeles, CA 90095, USA
| | - Keon Mahmoudi
- Department of Radiological Sciences, David Geffen School of Medicine at University of California Los Angeles, 757 Westwood Plaza, Suite 1621, Los Angeles, CA 90095, USA
| | - Adam Bauer
- Department of Radiology, Kaiser Permanente Fontana Medical Center, Fontana, CA 92335, USA
| | - Haoyue Zhang
- Department of Bioengineering, University of California Los Angeles, Los Angeles, CA 90095, USA
| | - Jennifer Polson
- Department of Bioengineering, University of California Los Angeles, Los Angeles, CA 90095, USA
| | - Corey Arnold
- Department of Radiological Sciences, David Geffen School of Medicine at University of California Los Angeles, 757 Westwood Plaza, Suite 1621, Los Angeles, CA 90095, USA
- Department of Bioengineering, University of California Los Angeles, Los Angeles, CA 90095, USA
| | - Nadejda M. Tsankova
- Department of Pathology and Laboratory Medicine, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Adilia Hormigo
- Department of Neurology, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Banafsheh Salehi
- Department of Radiological Sciences, David Geffen School of Medicine at University of California Los Angeles, 757 Westwood Plaza, Suite 1621, Los Angeles, CA 90095, USA
| | - Nancy Pham
- Department of Radiological Sciences, David Geffen School of Medicine at University of California Los Angeles, 757 Westwood Plaza, Suite 1621, Los Angeles, CA 90095, USA
| | - Benjamin M. Ellingson
- Department of Radiological Sciences, David Geffen School of Medicine at University of California Los Angeles, 757 Westwood Plaza, Suite 1621, Los Angeles, CA 90095, USA
- UCLA Brain Tumor Imaging Laboratory, Department of Radiological Sciences, David Geffen School of Medicine at University of California Los Angeles, Los Angeles, CA 90095, USA
| | - Timothy F. Cloughesy
- UCLA Brain Tumor Imaging Laboratory, Department of Radiological Sciences, David Geffen School of Medicine at University of California Los Angeles, Los Angeles, CA 90095, USA
- Department of Neurology, David Geffen School of Medicine at University of California Los Angeles, Los Angeles, CA 90095, USA
| | - Kambiz Nael
- Department of Radiological Sciences, David Geffen School of Medicine at University of California Los Angeles, 757 Westwood Plaza, Suite 1621, Los Angeles, CA 90095, USA
- Correspondence: ; Tel.: +1-310-267-5932
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Hernandez AM, Burkett GW, Pham N, Abbey CK, Boone JM. Performance of high-resolution CT for detection and discrimination tasks related to stenotic lesions - A phantom study using model observers. Med Phys 2022; 50:2037-2048. [PMID: 36583447 DOI: 10.1002/mp.16194] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Revised: 12/04/2022] [Accepted: 12/15/2022] [Indexed: 12/31/2022] Open
Abstract
BACKGROUND Accurate detection and grading of atheromatous stenotic lesions within the cardiac, renal, and intracranial vasculature is imperative for early recognition of disease and guiding treatment strategies. PURPOSE In this work, a stenotic lesion phantom was used to compare high resolution and normal resolution modes on the same CT scanner in terms of detection and size discrimination performance. MATERIALS AND METHODS The phantom is comprised of three acrylic cylinders (each 15.0 cm in diameter and 1.3 cm thick) with a matching array of holes in each module. The outer two modules contain holes that are slightly larger than the corresponding hole in the central module to simulate stenotic narrowing in vasculature. The stack of modules was submerged in an iodine solution simulating contrast-enhanced stenotic lesions with a range of lumen diameters (1.32-10.08 mm) and stenosis severity (0%, 50%, 60%, 70%, and 80%). The phantom was imaged on the Canon Aquilion Precision high-resolution CT scanner in high-resolution (HR) mode (0.25 mm × 0.50 mm detector element size) and normal-resolution (NR) mode (0.50 mm × 0.50 mm) using 120 kV and two dose levels (14 and 21 mGy SSDE) with 30 repeat scans acquired for each combination. Filtered back-projection (FBP) and a hybrid-iterative reconstruction (AIDR) were used with the FC18 kernel, as well as a deep learning algorithm (AiCE) which is only available for HR. A non-prewhitening model observer with an eye filter was implemented to quantify performance for detection and size discrimination tasks in the axial plane. RESULTS Detection performance improved with increasing diameter, dose, and for AIDR in comparison to FBP for a fixed resolution mode. Performance in the HR mode was generally higher than NR for the smaller lumen diameters (1-5 mm) with decreasing differences as the diameter increased. Performance in NR mode surpassed HR mode for lumen diameters greater than ∼4 mm and ∼5 mm for 14 mGy and 21 mGy, respectively. AiCE provided consistently higher detection performance compared with AIDR-FC18 (48% higher for a 6 mm lumen diameter). Discrimination performance increased with increasing nominal diameter, dose, and for larger differences in stenosis severity. When comparing discrimination performance in HR to NR modes, the largest relative differences occur at the smallest nominal diameters and smallest differences in stenosis severity. The AiCE reconstruction algorithm produced the highest overall discrimination performance values, and these were significantly higher than AIDR-FC18 for nominal diameters of 7.14 and 10.08 mm. CONCLUSIONS HR mode outperforms NR for detection up to a specific diameter and the results improve with AiCE and for higher dose levels. For the task of size discrimination, HR mode consistently outperforms NR if AIDR-FC18 is used for dose levels of at least 21 mGy, and the results improve with AiCE and for the smallest differences in stenosis severity investigated (50% vs. 60%). High-resolution CT appears to be beneficial for detecting smaller simulated lumen diameters (<5 mm) and is generally advantageous for discrimination tasks related to stenotic lesions, which inherently contain information at higher frequencies, given the right reconstruction algorithm and dose level.
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Affiliation(s)
- Andrew M Hernandez
- Department of Radiology, University of California Davis, Sacramento, California, USA
| | - George W Burkett
- Department of Radiology, University of California Davis, Sacramento, California, USA
| | - Nancy Pham
- Department of Radiology, University of California Los Angeles, Los Angeles, California, USA
| | - Craig K Abbey
- Department of Psychological & Brain Sciences, University of California Santa Barbara, Santa Barbara, California, USA
| | - John M Boone
- Department of Radiology, University of California Davis, Sacramento, California, USA.,Department of Biomedical Engineering, University of California Davis, Davis, California, USA
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Chirayath TW, Pham N, Duranton C, Rubera I, Gauffenic A, Cohen Solal M, Latourte A, Bardin T, Richette P, Lioté F, Ea HK. POS1169 THE INFLAMMATION INDUCED BY MONOSODIUM URATE AND CALCIUM PYROPHOSPHATE CRYSTALS DEPENDS ON OSMOLARITY AND AQUAPORIN CHANNELS. Ann Rheum Dis 2022. [DOI: 10.1136/annrheumdis-2022-eular.3571] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
BackgroundThe inflammation induced by monosodium urate (MSU) and calcium pyrophosphate (CPP) crystals is driven by interleukin (IL)-1β production. This later relies on NLRP3 inflammasome which can be activated by variation of ion concentration.ObjectivesTo assess the role of osmolarity and water flux in MSU and CPP crystal-induced inflammation.MethodsIn vitro, THP1 monocytes were stimulated by pyrogen-free synthetic MSU and CPP crystals in iso-, hypo- or hyperosmotic media. Cytokine production was quantified by ELISA in cell culture supernatants. Cell size was measured using video microscopy. The role of aquaporin channels was assessed by pharmacological inhibitor (mercury chloride, HgCl2). In vivo, murine air pouch model was used. MSU and CPP crystals were injected in air pouch of mice treated or not with HgCl2 or mannitol. Osmolarity of mouse sera and patient synovial fluids (SF) were measured using freezing point osmometer. The size of cells collected from SF was assessed with imageJ software.ResultsMSU and CPP crystal-induced IL-1β production was substantially reduced by HgCl2 treatment (MSU 4900 vs 880 pg/ml; CPP 10500 vs 980, p<0.0001) or when cells were cultured in hyperosmotic medium. MSU and CPP crystals induced a transient increase in cell size which was 1.6 and 1.5 bigger after 30 and 100 min of stimulation by MSU and CPP crystals, respectively. After 150 min of stimulation, cell size decreased to their baseline size. Cell size increase was abolished by HgCl2 or hyperosmotic medium. In vivo, MSU and CPP crystal-induced inflammation (assessed by cell infiltration, IL-1β and CXCL2 production in air pouch lavage) was drastically reduced by HgCl2 or mannitol treatment. The serum osmolarity was higher in mannitol-treated mice than untreated mice (320 vs 300 mmosm/L). In patients, cells collected from SF during CPP or MSU crystal-induced flares had a bigger size than cells collected from osteoarthitic SF. The osmolarity of MSU or CPP crystal-containing SF was lower than the osmolarity of osteoarthritic SF (270 vs 310 mmosm/L). Finally, the IL-1β concentration in SF was strongly correlated with cell size and SF osmolarity.ConclusionThese results suggest that the variation of osmolarity plays central role in MSU and CPP crystal-induced inflammation. Deciphering how crystals modulate osmolarity will identify new therapeutic targets.Disclosure of InterestsNone declared
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Abstract
Artificial intelligence (AI) can be applied to head and neck imaging to augment image quality and various clinical tasks including segmentation of tumor volumes, tumor characterization, tumor prognostication and treatment response, and prediction of metastatic lymph node disease. Head and neck oncology care is well positioned for the application of AI since treatment is guided by a wealth of information derived from CT, MRI, and PET imaging data. AI-based methods can integrate complex imaging, histologic, molecular, and clinical data to model tumor biology and behavior, and potentially identify associations, far beyond what conventional qualitative imaging can provide alone.
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Affiliation(s)
- Nancy Pham
- Neuroradiology, Radiology Department, University of California Los Angeles David Geffen School of Medicine, Los Angeles, CA; Neuroradiology, Radiology Department, University of Illinois.
| | - Connie Ju
- Neuroradiology, Radiology Department, University of California Los Angeles David Geffen School of Medicine, Los Angeles, CA
| | - Tracie Kong
- Neuroradiology, Radiology Department, University of California Los Angeles David Geffen School of Medicine, Los Angeles, CA
| | - Suresh K Mukherji
- Neuroradiology, Radiology Department, University of California Los Angeles David Geffen School of Medicine, Los Angeles, CA
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Pham N, Raslan O, Strong EB, Boone J, Dublin A, Chen S, Hacein-Bey L. High-Resolution CT Imaging of the Temporal Bone: A Cadaveric Specimen Study. J Neurol Surg B Skull Base 2022; 83:470-475. [PMID: 36091630 PMCID: PMC9462966 DOI: 10.1055/s-0041-1741006] [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] [Received: 01/19/2021] [Accepted: 11/12/2021] [Indexed: 02/02/2023] Open
Abstract
Objective Super-high and ultra-high spatial resolution computed tomography (CT) imaging can be advantageous for detecting temporal bone pathology and guiding treatment strategies. Methods Six temporal bone cadaveric specimens were used to evaluate the temporal bone microanatomic structures utilizing the following CT reconstruction modes: normal resolution (NR, 0.5-mm slice thickness, 512 2 matrix), high resolution (HR, 0.5-mm slice thickness, 1,024 2 matrix), super-high resolution (SHR, 0.25-mm slice thickness, 1,024 2 matrix), and ultra-high resolution (UHR, 0.25-mm slice thickness, 2,048 2 matrix). Noise and signal-to-noise ratio (SNR) for bone and air were measured at each reconstruction mode. Two observers assessed visualization of seven small anatomic structures using a 4-point scale at each reconstruction mode. Results Noise was significantly higher and SNR significantly lower with increases in spatial resolution (NR, HR, and SHR). There was no statistical difference between SHR and UHR imaging with regard to noise and SNR. There was significantly improved visibility of all temporal bone osseous structures of interest with SHR and UHR imaging relative to NR imaging ( p < 0.001) and most of the temporal bone osseous structures relative to HR imaging. There was no statistical difference in the subjective image quality between SHR and UHR imaging of the temporal bone ( p ≥ 0.085). Conclusion Super-high-resolution and ultra-high-resolution CT imaging results in significant improvement in image quality compared with normal-resolution and high-resolution CT imaging of the temporal bone. This preliminary study also demonstrates equivalency between super-high and ultra-high spatial resolution temporal bone CT imaging protocols for clinical use.
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Affiliation(s)
- Nancy Pham
- Department of Radiology, University of California, Los Angeles, California, United States,Address for correspondence Nancy Pham, MD Department of Radiology, University of California757 Westwood Plaza, Suite 1621D, Los Angeles, CA 90095-7532United States
| | - Osama Raslan
- Department of Radiology, University of California, Davis, Sacramento, California, United States
| | - Edward B. Strong
- Department of Otolaryngology, University of California, Davis, Sacramento, California, United States
| | - John Boone
- Department of Radiology, University of California, Davis, Sacramento, California, United States
| | - Arthur Dublin
- Department of Radiology, University of California, Davis, Sacramento, California, United States
| | - Shuai Chen
- Division of Biostatistics, Department of Public Health Sciences, University of California, Davis, California, United States
| | - Lotfi Hacein-Bey
- Department of Radiology, University of California, Davis, Sacramento, California, United States
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Mikubo M, Li Q, Filho S, Inoue Y, Pham N, Moghal N, Tsao M. P71.02 Molecular and Cellular Dynamics of Drug-Tolerant Persister (DTP) Cells During Osimertinib Therapy in EGFR Mutant Lung Adenocarcinoma. J Thorac Oncol 2021. [DOI: 10.1016/j.jtho.2021.08.731] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Alonso JE, Ishiyama GP, Fujiwara RJT, Pham N, Ledbetter L, Ishiyama A. Cochlear Meniere's: A Distinct Clinical Entity With Isolated Cochlear Hydrops on High-Resolution MRI? Front Surg 2021; 8:680260. [PMID: 34222320 PMCID: PMC8242163 DOI: 10.3389/fsurg.2021.680260] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [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] [Received: 03/13/2021] [Accepted: 05/10/2021] [Indexed: 11/16/2022] Open
Abstract
Objective: Describe the clinical characteristics of patients with isolated cochlear endolymphatic hydrops (EH). Study design: Clinical case series. Setting: Tertiary Neurotology referral clinic. Patients: All subjects presenting to a University Neurotology clinic during a 1-year period from July 2015 until August 2016 who had isolated cochlear EH on MRI. Patients with a history of temporal bone surgery prior to the MRI were excluded. Intervention: High-resolution delayed-intravenous contrast MRI. Main outcome measures: Audiometric and vestibular testing, clinical history analysis. Results: 10 subjects demonstrated isolated, unilateral cochlear hydrops on MRI. None of these patients met the criteria for Meniere's disease. Mean age of the group was 66.4 years and most were males (70%). Unilateral aural fullness (70%), tinnitus (80%), and hearing loss (90%) were frequently observed. Only one patient presented with unsteadiness (10%) and one patient had a single isolated spell of positional vertigo 1 month prior to the MRI (10%) but no further vertigo spells in the 4 years following the MRI. The mean PTA was 37.8 dB which was significantly decreased from the non-affected ear with PTA of 17.9 (p < 0.001). One patient developed vertiginous spells and unsteadiness 4 years after initial presentation and a repeat MRI revealed progression to utricular, saccular and cochlear hydrops. Vestibular testing was obtained in five patients with one patient presenting with 50% caloric paresis and all others normal. The most common treatment tried was acetazolamide in seven patients with 86% reporting subjective clinical improvement. Two out of the 10 patients had a history of migraine (20%). Conclusions: Patients with MRI exhibiting isolated cochlear EH present with predominantly auditory symptoms: mild to moderate low-frequency hearing loss, aural fullness, tinnitus without significant vertigo. Isolated cochlear hydrops is more common in males, average age in mid-60's and there is a low comorbidity of migraine headaches. This contrasts significantly with patients with isolated saccular hydrops on MRI from our prior studies. We believe that isolated cochlear EH with hearing loss but no vertigo is distinct from Meniere's disease or its variant delayed endolymphatic hydrops. We propose that cochlear Meniere's disease represents a distinct clinical entity that could be a variant of Meniere's disease.
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Affiliation(s)
- Jose E. Alonso
- Department of Head and Neck Surgery, University of California, Los Angeles, Los Angeles, CA, United States
| | - Gail P. Ishiyama
- Department of Neurology, University of California, Los Angeles, Los Angeles, CA, United States
| | - Rance J. T. Fujiwara
- Department of Head and Neck Surgery, University of California, Los Angeles, Los Angeles, CA, United States
| | - Nancy Pham
- Department of Neuroradiology, University of California, Los Angeles, Los Angeles, CA, United States
| | - Luke Ledbetter
- Department of Neuroradiology, University of California, Los Angeles, Los Angeles, CA, United States
| | - Akira Ishiyama
- Department of Head and Neck Surgery, University of California, Los Angeles, Los Angeles, CA, United States
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Pham N, Ebinu JO, Karnati T, Hacein-Bey L. Neuroimaging findings and pathophysiology of dorsal spinal arachnoid webs: illustrative case. Journal of Neurosurgery: Case Lessons 2021; 1:CASE2142. [PMID: 35855021 PMCID: PMC9245846 DOI: 10.3171/case2142] [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] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/20/2021] [Accepted: 02/28/2021] [Indexed: 11/16/2022]
Abstract
BACKGROUND Spinal arachnoid webs are uncommon and difficult to diagnose, especially because causative intradural transverse bands of arachnoid tissue are radiographically occult. Left untreated, arachnoid webs may cause progressive, debilitating, and permanent neurological dysfunction. Conversely, more than 90% of patients may experience rapid neurological recovery after resection, even with a prolonged duration of presenting symptoms. Indirect imaging signs such as spinal cord indentation and compression with cerebrospinal fluid (CSF) flow alteration provide crucial diagnostic clues that are critical in guiding appropriate management of such patients. OBSERVATIONS The authors reported a patient with no significant medical history who presented with back pain, progressive lower extremity weakness, gait ataxia, and bowel and bladder incontinence. They discussed multimodality imaging for determining the presence of arachnoid webs, including magnetic resonance imaging, phase-contrast CSF flow study, computed tomography myelography, and intraoperative ultrasound. They also discussed the detailed anatomy of the spinal subarachnoid space and a plausible pathophysiological mechanism for dorsal arachnoid webs. LESSONS The authors report on a patient who underwent comprehensive imaging evaluation detailing the arachnoid web and whose subsequent anatomical localization and surgical treatment resulted in a full neurological recovery.
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Affiliation(s)
- Nancy Pham
- Department of Radiology, University of California, Los Angeles, David Geffen School of Medicine, Los Angeles, California; and
| | | | | | - Lotfi Hacein-Bey
- Radiology, University of California, Davis, School of Medicine, Sacramento, California
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Pham N, Le N, Olson L, Larsson M, Tran D. Epidemiology and effective pertussis vaccination among hospitalized children in Vietnam National Children's Hospital, 2015–2018. Int J Infect Dis 2020. [DOI: 10.1016/j.ijid.2020.09.1160] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
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Martins-Filho S, Fares A, Raghavan V, Stewart E, Ravi D, Perdrizet K, Weiss J, Hueniken K, Patel D, Pham N, Sacher A, Bradbury P, Leighl N, Shepherd F, Tsao M, Liu G. P2.03-11 Impact of Ethnicity on Outcome in Never Smokers with EGFR and ALK Wildtype (EGFR/ALK-Wildtype) Lung Adenocarcinomas. J Thorac Oncol 2019. [DOI: 10.1016/j.jtho.2019.08.1458] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Stewart E, Navab R, Martins-Filho S, Pham N, Liu G, Tsao M. P2.14-40 Tumor-Stromal Microenvironment Interactions in a PDX Model of EGFR TKI Drug Tolerance. J Thorac Oncol 2019. [DOI: 10.1016/j.jtho.2019.08.1825] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Tsao M, Shi R, Radulovich N, Ng C, Notsuda H, Cabanero M, Martins-Filho S, Raghavan V, Li Q, Mer A, Liu N, Pham N, Haibe-Kains B, Liu G, Moghal N. OA08.01 Organoid Cultures as Novel Preclinical Models of Non-Small Cell Lung Cancer. J Thorac Oncol 2019. [DOI: 10.1016/j.jtho.2019.08.447] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Miller C, Small W, Martin B, Pham N, Tanimoto K, Faaiza V, Godellas C, Thomas T. How Should We Proceed with ypN+ Breast Cancer Following Positive Sentinel Lymph Node Biopsy after Neoadjuvant Chemotherapy? Int J Radiat Oncol Biol Phys 2018. [DOI: 10.1016/j.ijrobp.2018.07.1583] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Martins-Filho S, Cabanero M, Pham N, Stewart E, Ravi D, Patel D, Mcconnell J, Grindlay A, Allison F, Li M, Shepherd F, Tsao M, Yasufuku K, Liu G. MA27.01 Establishment of PDX From Tumors Characterized by EGFR Mutations or ALK Fusion Genes from Resections, Biopsies and Pleural Fluids. J Thorac Oncol 2018. [DOI: 10.1016/j.jtho.2018.08.547] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Notsuda H, Pham N, Li M, Liu N, Raghavan V, Fang Z, Marshall C, Moghal N, Ikura M, Tsao M. MA27.07 Lung Adenocarcinoma Harboring BRAF G469V Mutation is Uniquely Sensitive to EGFR Tyrosine Kinase Inhibitors. J Thorac Oncol 2018. [DOI: 10.1016/j.jtho.2018.08.552] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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Moghal N, Pham N, Shi R, Radulovich N, Li M, Raghavan V, Li Q, Wang D, Tong J, Zhu C, Li L, Stewart E, Tamblyn L, Weiss J, Martins-Filho S, Ravi D, Pintilie M, Moran M, Liu G, Leighl N, Shepherd F, Tsao M. MTE01.02 Lung Patient Derived Xenograft and Organoid. J Thorac Oncol 2018. [DOI: 10.1016/j.jtho.2018.08.048] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Li EC, Tran C, Chen SCS, Pham N, Hertler AA. Design and implementation of a novel value framework for oncology clinical pathway decision-making: Chemotherapy comparative index and scale. J Clin Oncol 2018. [DOI: 10.1200/jco.2018.36.15_suppl.e18925] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Affiliation(s)
- Edward C. Li
- University of New England College of Pharmacy, Portland, ME
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Notsuda H, Radulovich N, Ng C, Tamblyn L, Cabanero M, Li M, Pham N, Tsao M. P1.02-016 Establishment of Lung Adenocarcinoma Organoid Cultures. J Thorac Oncol 2017. [DOI: 10.1016/j.jtho.2017.09.748] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Dinh J, Pham N, Dalwadi S, Jhaveri P. Practice Patterns in Malignant Mesotheliom. Int J Radiat Oncol Biol Phys 2017. [DOI: 10.1016/j.ijrobp.2017.06.1686] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Nieto K, Martin B, Palmere L, Brennan K, Pham N, Albuquerque K, Liotta M, Small W, Harkenrider M. Does chemotherapy increase the pelvic toxicity of vaginal brachytherapy for endometrial cancer patients? Gynecol Oncol 2017. [DOI: 10.1016/j.ygyno.2017.03.427] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Gajjar S, Jhaveri P, Pham N. Factors Impacting Compliance With Lung Radiation Therapy Within a Large Metropolitan Population. Int J Radiat Oncol Biol Phys 2016. [DOI: 10.1016/j.ijrobp.2016.06.1851] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Pham N, Asper J, Bonnen M, Jhaveri P. Pretreatment Peer Review: A Way to Increase Efficiency and Effectiveness of Departmental Peer Review. Int J Radiat Oncol Biol Phys 2016. [DOI: 10.1016/j.ijrobp.2016.06.1983] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Anthony G, Cunliffe A, Castillo R, Pham N, Guerrero T, Armato S, Al-Hallaq H. SU-E-J-251: Incorporation of Pre-Therapy 18F-FDG Uptake with CT Texture Features in a Predictive Model for Radiation Pneumonitis Development. Med Phys 2015. [DOI: 10.1118/1.4924337] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Silva M, Pham N, Lewis C, Iyer S, Kwok E, Solomon G, Zeise L. A Comparison of ToxCast Test Results with In Vivo and Other In Vitro Endpoints for Neuro, Endocrine, and Developmental Toxicities: A Case Study Using Endosulfan and Methidathion. ACTA ACUST UNITED AC 2015; 104:71-89. [PMID: 26017137 DOI: 10.1002/bdrb.21140] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2015] [Accepted: 04/27/2015] [Indexed: 11/10/2022]
Abstract
INTRODUCTION The U.S. Environmental Protection Agency's (EPA's) Toxicity Forecaster (ToxCast) is a potential tool for chemical prioritization, hazard identification, and risk assessment. We conducted a case study to compare ToxCast data with endpoints from other in vitro and in vivo studies for two data-rich pesticides: endosulfan and methidathion. METHODS ToxCast assays for endocrine disruption, development (zebrafish), and neurotoxicity were qualitatively compared to traditional neurotoxicity, developmental and reproductive toxicity findings. We also used in vitro-in vivo extrapolation to convert half-maximal activity concentrations in active ToxCast assays to rat oral equivalent doses, and quantitatively compared these to the lowest observable effect level (LOEL) from in vivo studies. RESULTS Endosulfan was inactive for GABAA R, unlike in vivo; but active with dopamine transporter assays and was neurotoxic in zebrafish as expected. Methidathion was not active for these endpoints in vivo or in vitro. Acetylcholinesterase inhibition was ToxCast-inactive, although both pesticides are inhibitors in vivo. ToxCast results were generally inactive for endosulfan estrogen receptor agonism and androgen receptor antagonism unlike in vivo. Calculated oral equivalent doses for estrogen receptor and androgen receptor pathways and for zebrafish assays for both compounds were generally consistent with in vivo LOELs. Endosulfan showed neurotoxicity and both pesticides showed developmental effects in the zebrafish assays, although methidathion is not developmentally toxic in vivo. CONCLUSIONS ToxCast's predictions showed concordance on some endpoints and nonconcordance, consisting mainly of false inactives, in several critical endpoints, likely due to a lack of metabolic activation and limitations in assay design. Zebrafish assays were good predictors of developmental toxicity and neurotoxicity for endosulfan.
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Affiliation(s)
- M Silva
- Department of Pesticide Regulation, California Environmental Protection Agency (CalEPA), Sacramento, California
| | - N Pham
- CalEPA's Office of Environmental Health Hazard Assessment (OEHHA), Sacramento, California
| | - C Lewis
- Department of Pesticide Regulation, California Environmental Protection Agency (CalEPA), Sacramento, California
| | - S Iyer
- CalEPA's Office of Environmental Health Hazard Assessment (OEHHA), Sacramento, California
| | - E Kwok
- Department of Pesticide Regulation, California Environmental Protection Agency (CalEPA), Sacramento, California
| | - G Solomon
- Office of the Secretary, CalEPA, Sacramento, California
| | - L Zeise
- CalEPA's Office of Environmental Health Hazard Assessment (OEHHA), Sacramento, California
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Pham N, Castillo R, Castillo R, Hobbs B, Guerrero T. Higher Doses to Smaller Volumes Explains Higher Proton Therapy Radiation Pneumonitis Rates Found. Int J Radiat Oncol Biol Phys 2014. [DOI: 10.1016/j.ijrobp.2014.05.209] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Orbai AM, Truedsson L, Sturfelt G, Nived O, Fang H, Alarcón GS, Gordon C, Merrill J, Fortin PR, Bruce IN, Isenberg DA, Wallace DJ, Ramsey-Goldman R, Bae SC, Hanly JG, Sanchez-Guerrero J, Clarke AE, Aranow CB, Manzi S, Urowitz MB, Gladman DD, Kalunian KC, Costner MI, Werth VP, Zoma A, Bernatsky S, Ruiz-Irastorza G, Khamashta MA, Jacobsen S, Buyon JP, Maddison P, Dooley MA, Van Vollenhoven RF, Ginzler E, Stoll T, Peschken C, Jorizzo JL, Callen JP, Lim SS, Fessler BJ, Inanc M, Kamen DL, Rahman A, Steinsson K, Franks AG, Sigler L, Hameed S, Pham N, Brey R, Weisman MH, McGwin G, Magder LS, Petri M. Anti-C1q antibodies in systemic lupus erythematosus. Lupus 2014; 24:42-9. [PMID: 25124676 DOI: 10.1177/0961203314547791] [Citation(s) in RCA: 85] [Impact Index Per Article: 8.5] [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: 01/02/2023]
Abstract
OBJECTIVE Anti-C1q has been associated with systemic lupus erythematosus (SLE) and lupus nephritis in previous studies. We studied anti-C1q specificity for SLE (vs rheumatic disease controls) and the association with SLE manifestations in an international multicenter study. METHODS Information and blood samples were obtained in a cross-sectional study from patients with SLE (n = 308) and other rheumatologic diseases (n = 389) from 25 clinical sites (84% female, 68% Caucasian, 17% African descent, 8% Asian, 7% other). IgG anti-C1q against the collagen-like region was measured by ELISA. RESULTS Prevalence of anti-C1q was 28% (86/308) in patients with SLE and 13% (49/389) in controls (OR = 2.7, 95% CI: 1.8-4, p < 0.001). Anti-C1q was associated with proteinuria (OR = 3.0, 95% CI: 1.7-5.1, p < 0.001), red cell casts (OR = 2.6, 95% CI: 1.2-5.4, p = 0.015), anti-dsDNA (OR = 3.4, 95% CI: 1.9-6.1, p < 0.001) and anti-Smith (OR = 2.8, 95% CI: 1.5-5.0, p = 0.01). Anti-C1q was independently associated with renal involvement after adjustment for demographics, ANA, anti-dsDNA and low complement (OR = 2.3, 95% CI: 1.3-4.2, p < 0.01). Simultaneously positive anti-C1q, anti-dsDNA and low complement was strongly associated with renal involvement (OR = 14.9, 95% CI: 5.8-38.4, p < 0.01). CONCLUSIONS Anti-C1q was more common in patients with SLE and those of Asian race/ethnicity. We confirmed a significant association of anti-C1q with renal involvement, independent of demographics and other serologies. Anti-C1q in combination with anti-dsDNA and low complement was the strongest serological association with renal involvement. These data support the usefulness of anti-C1q in SLE, especially in lupus nephritis.
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Affiliation(s)
- A-M Orbai
- Division of Rheumatology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - L Truedsson
- Department of Laboratory Medicine, Section of Microbiology, Immunology and Glycobiology, Lund University, Lund, Sweden
| | - G Sturfelt
- Department of Rheumatology, Skåne University Hospital, Lund, Sweden
| | - O Nived
- Department of Rheumatology, Skåne University Hospital, Lund, Sweden
| | - H Fang
- Division of Rheumatology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - G S Alarcón
- Department of Medicine, Division of Clinical Immunology and Rheumatology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - C Gordon
- Rheumatology Research Group, School of Immunity and Infection, College of Medical and Dental Sciences University of Birmingham, Birmingham, UK
| | - Jt Merrill
- Department of Clinical Pharmacology, Oklahoma Medical Research Foundation, Oklahoma City, OK, USA
| | - P R Fortin
- Division of Rheumatology, Department of Medicine, Centre Hospitalier Universitaire (CHU) de Québec Axe Maladies Infectieuses et Immunitaires, CRCHU de Québec, Université Laval, Quebec City, Quebec, Canada
| | - I N Bruce
- Arthritis Research UK Centre for Epidemiology, Centre for Musculoskeletal Research, Institute of Inflammation and Repair, Manchester Academic Health Sciences Centre, The University of Manchester, Manchester, UK NIHR Manchester Musculoskeletal Biomedical Research Unit, Central Manchester University Hospitals NHS Foundation Trust, Manchester Academic Health Science Centre, UK
| | - D A Isenberg
- Centre for Rheumatology, Research Division of Medicine, London, UK
| | - D J Wallace
- Cedars-Sinai Medical Center, David Geffen School of Medicine, University of California, Los Angeles, CA, USA
| | - R Ramsey-Goldman
- Northwestern University, Feinberg School of Medicine, Chicago, IL, USA
| | - S-C Bae
- Department of Rheumatology, Hanyang University Hospital for Rheumatic Diseases, Seoul, Korea
| | - J G Hanly
- Division of Rheumatology, Departments of Medicine and Pathology Capital Health and Dalhousie University, Halifax, Nova Scotia, Canada
| | - J Sanchez-Guerrero
- Mount Sinai Hospital and University Health Network, Toronto, Ontario, Canada
| | - A E Clarke
- Divisions of Clinical Epidemiology and Rheumatology, McGill University Health Centre, Montreal, Quebec, Canada
| | - C B Aranow
- Feinstein Institute for Medical Research, Manhasset, NY, USA
| | - S Manzi
- Department of Medicine, Division of Rheumatology, Allegheny Singer Research Institute, Allegheny General Hospital, Pittsburgh, PA, USA
| | - M B Urowitz
- Toronto Western Hospital Toronto, Ontario, Canada
| | - D D Gladman
- Toronto Western Hospital Toronto, Ontario, Canada
| | - K C Kalunian
- Division of Rheumatology, Allergy and Immunology, UCSD School of Medicine, La Jolla, CA, USA
| | - M I Costner
- North Dallas Dermatology Associates, Dallas, TX, USA
| | - V P Werth
- Philadelphia VA Medical Center and University of Pennsylvania, Philadelphia, PA, USA
| | - A Zoma
- Lanarkshire Centre for Rheumatology and Hairmyres Hospital, East Kilbride, UK
| | - S Bernatsky
- Divisions of Clinical Epidemiology and Rheumatology, McGill University Health Centre, Montreal, Quebec, Canada
| | - G Ruiz-Irastorza
- Autoimmune Diseases Research Unit, Hospital Universitario Cruces Universidad del Pais Vasco, Barakaldo, Spain
| | | | - S Jacobsen
- Rigshospitalet, Copenhagen University Hospital, Copenhagen, Denmark
| | - J P Buyon
- New York University, New York, NY, USA
| | | | - M A Dooley
- University of North Carolina, Chapel Hill, NC, USA
| | | | - E Ginzler
- State University of New York, Downstate Medical Center, Brooklyn, NY, USA
| | - T Stoll
- Kantonsspital Schaffhausen, Schaffhausen, Switzerland
| | - C Peschken
- University of Manitoba Winnipeg, Manitoba, Canada
| | - J L Jorizzo
- Wake Forest University, Winston-Salem, NC, USA
| | - J P Callen
- University of Louisville, Louisville, KY, USA
| | - S S Lim
- Emory University, Atlanta, GA, USA
| | - B J Fessler
- Department of Medicine, Division of Clinical Immunology and Rheumatology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - M Inanc
- Division of Rheumatology, Department of Internal Medicine, Istanbul Medical Faculty, Istanbul University, Istanbul, Turkey
| | - D L Kamen
- Medical University of South Carolina, Charleston, SC, USA
| | - A Rahman
- NIHR Manchester Musculoskeletal Biomedical Research Unit, Central Manchester University Hospitals NHS Foundation Trust, Manchester Academic Health Science Centre, UK
| | - K Steinsson
- Landspitali University Hospital, Reykjavik, Iceland
| | | | - L Sigler
- Division of Rheumatology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - S Hameed
- Division of Rheumatology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - N Pham
- Division of Rheumatology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - R Brey
- University of Texas Health Science Center, San Antonio, TX, USA
| | - M H Weisman
- Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - G McGwin
- Department of Medicine, Division of Clinical Immunology and Rheumatology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - L S Magder
- Department of Epidemiology and Public Health, University of Maryland, Baltimore, MD, USA
| | - M Petri
- Division of Rheumatology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
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Cunliffe A, Armato S, Castillo R, Pham N, Guerrero T, Al-Hallaq H. TU-A-12A-04: Quantitative Texture Features Calculated in Lung Tissue From CT Scans Demonstrate Consistency Between Two Databases From Different Institutions. Med Phys 2014. [DOI: 10.1118/1.4889250] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Pham N, Zaitoun H, Mohammed TL, DeLaPena-Almaguer E, Martinez F, Novaro GM, Kirsch J. Complications of Aortic Valve Surgery: Manifestations at CT and MR Imaging. Radiographics 2012; 32:1873-92. [DOI: 10.1148/rg.327115735] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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Diéras V, Bonnefoi H, Alba E, Awada A, Coudert B, Pivot X, Gligorov J, Jäger A, Gianni L, Lindeman G, Pham N, Su Y, Gao G, Mery-Mignard D, Paridaens R, Verweij J. P3-16-08: A Phase 2, Randomized Open-Label Study of Iniparib, Administered Either Weekly or Twice-Weekly in Combination with Gemcitabine Plus Carboplatin in Patients with mTNBC. Cancer Res 2011. [DOI: 10.1158/0008-5472.sabcs11-p3-16-08] [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] [Indexed: 11/16/2022]
Abstract
Abstract
Background
Iniparib (BSI-201) is an investigational anticancer agent whose precise mechanism of action is under active investigation. In breast cancer cell lines and xenograft models of triple-negative breast cancer (TNBC), iniparib exhibits anti-proliferative activity and potentiates the cell cycle effects of some DNA damaging agents. In a randomized, open-label phase 2 study in pts with metastatic TNBC (mTNBC), iniparib combined with gemcitabine (G) and carboplatin (C) (GC) improved efficacy outcomes compared with GC alone. A confirmatory phase 3 study with GCI failed to meet pre-specified criteria for PFS and OS; however, an exploratory subset analysis demonstrated a potential benefit amongst 2nd/3rd line pts (O'Shaughnessy et al. ASCO 2011). Here we report results of a randomized phase 2 study (NCT01045304) in pts with mTNBC, which assesses efficacy and pharmacokinetics (PK) of iniparib administered either biw or qw in combination with GC.
Patients and methods: Eligible pts (N=163; median age 49 yrs) had documented and measurable TNBC, ECOG PS 0–1, normal organ/marrow function, and had received ≤2 prior chemotherapy (CT) regimens for metastatic disease. Pts were randomized (1:1) to receive G (1,000 mg/m2, IV, d 1, 8) plus C (AUC 2, IV, d 1, 8) and iniparib either biw (5.6 mg/kg, IV d 1,4,8,11) or qw (11.2 mg/kg, IV d 1,8) on a 21 d cycle. Pts were stratified according to prior CT for mTNBC (0 vs. 1–2). The primary efficacy endpoint was overall response rate (ORR; CR + PR); secondary endpoints included: clinical benefit rate (CBR; CR + PR + SD for 24 weeks), PFS, OS and PK.
Results: At the time of analysis, 23% of patients were still on treatment. The median number of cycles administered per patient was 6 in both arms; exposure to iniparib was identical. Safety data are not fully validated. All pts experienced at least 1 treatment emergent adverse event (TEAE). Grade (Gr) ≥3 TEAEs occurred in 94% and 85% of pts in the biw and qw arms, respectively. TEAEs Gr ≥3 occurring in ≥5% of pts regardless of relationship to study drug (biw vs qw) are as follows: blood and lymphatic 71% vs 67%; hepatobiliary 7.5% vs 9.8%; asthenia/fatigue 7.5% vs 11%; GI 8.8% vs 8.5%; infections 7.5% vs 3.7%; respiratory, thoracic and mediastinal 5% vs 8.5%, metabolism and nutrition 4% vs 6%. For response data see table.
No major difference was observed in drug exposure (based on AUC within one cycle) between the two dosing regimens.
Conclusion: Dosing of GCI on a qw schedule produced a similar ORR to that obtained with the biw schedule. A comparable safety profile in both arms, and consistency with results of previous studies, suggests that the weekly combination of GCI may be an appropriate schedule for further studies evaluating this combination. OS and PFS data are not yet mature; updated efficacy and safety data will be presented.
Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P3-16-08.
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Affiliation(s)
- V Diéras
- 1Institut Curie, Paris, Cedex 05, France; Université de Bordeaux, Bordeaux, INSERM, France; Hospital Clínico Universitario Virgen de la Victoria, Málaga, Spain; Institut Jules Bordet, Centre des Tumeurs de l'Université Libre de Bruxelles, Brussells, Belgium; Centre Georges François Leclerc, Dijon, France; University Hospital Jean Minjoz, Besançon, France; University Paris VI, Paris, France; Erasmus University Medical Center, Daniel den Hoed Cancer Center, Rotterdam, Netherlands; hSR - San Raffaele, Milan, Italy; The Royal Melbourne Hospital and The Walter and Eliza Hall Institute of Medical Research, Melbourne, Victoria, Australia; Sanofi, Vitry, Paris, France; Sanofi, Great Valley, PA; Sanofi, Cambridge, MA; University Hospital Gasthuisberg, Catholic University of Leuven, Leuven, Belgium; Erasmus University Medical Center, Rotterdam, Netherlands
| | - H Bonnefoi
- 1Institut Curie, Paris, Cedex 05, France; Université de Bordeaux, Bordeaux, INSERM, France; Hospital Clínico Universitario Virgen de la Victoria, Málaga, Spain; Institut Jules Bordet, Centre des Tumeurs de l'Université Libre de Bruxelles, Brussells, Belgium; Centre Georges François Leclerc, Dijon, France; University Hospital Jean Minjoz, Besançon, France; University Paris VI, Paris, France; Erasmus University Medical Center, Daniel den Hoed Cancer Center, Rotterdam, Netherlands; hSR - San Raffaele, Milan, Italy; The Royal Melbourne Hospital and The Walter and Eliza Hall Institute of Medical Research, Melbourne, Victoria, Australia; Sanofi, Vitry, Paris, France; Sanofi, Great Valley, PA; Sanofi, Cambridge, MA; University Hospital Gasthuisberg, Catholic University of Leuven, Leuven, Belgium; Erasmus University Medical Center, Rotterdam, Netherlands
| | - E Alba
- 1Institut Curie, Paris, Cedex 05, France; Université de Bordeaux, Bordeaux, INSERM, France; Hospital Clínico Universitario Virgen de la Victoria, Málaga, Spain; Institut Jules Bordet, Centre des Tumeurs de l'Université Libre de Bruxelles, Brussells, Belgium; Centre Georges François Leclerc, Dijon, France; University Hospital Jean Minjoz, Besançon, France; University Paris VI, Paris, France; Erasmus University Medical Center, Daniel den Hoed Cancer Center, Rotterdam, Netherlands; hSR - San Raffaele, Milan, Italy; The Royal Melbourne Hospital and The Walter and Eliza Hall Institute of Medical Research, Melbourne, Victoria, Australia; Sanofi, Vitry, Paris, France; Sanofi, Great Valley, PA; Sanofi, Cambridge, MA; University Hospital Gasthuisberg, Catholic University of Leuven, Leuven, Belgium; Erasmus University Medical Center, Rotterdam, Netherlands
| | - A Awada
- 1Institut Curie, Paris, Cedex 05, France; Université de Bordeaux, Bordeaux, INSERM, France; Hospital Clínico Universitario Virgen de la Victoria, Málaga, Spain; Institut Jules Bordet, Centre des Tumeurs de l'Université Libre de Bruxelles, Brussells, Belgium; Centre Georges François Leclerc, Dijon, France; University Hospital Jean Minjoz, Besançon, France; University Paris VI, Paris, France; Erasmus University Medical Center, Daniel den Hoed Cancer Center, Rotterdam, Netherlands; hSR - San Raffaele, Milan, Italy; The Royal Melbourne Hospital and The Walter and Eliza Hall Institute of Medical Research, Melbourne, Victoria, Australia; Sanofi, Vitry, Paris, France; Sanofi, Great Valley, PA; Sanofi, Cambridge, MA; University Hospital Gasthuisberg, Catholic University of Leuven, Leuven, Belgium; Erasmus University Medical Center, Rotterdam, Netherlands
| | - B Coudert
- 1Institut Curie, Paris, Cedex 05, France; Université de Bordeaux, Bordeaux, INSERM, France; Hospital Clínico Universitario Virgen de la Victoria, Málaga, Spain; Institut Jules Bordet, Centre des Tumeurs de l'Université Libre de Bruxelles, Brussells, Belgium; Centre Georges François Leclerc, Dijon, France; University Hospital Jean Minjoz, Besançon, France; University Paris VI, Paris, France; Erasmus University Medical Center, Daniel den Hoed Cancer Center, Rotterdam, Netherlands; hSR - San Raffaele, Milan, Italy; The Royal Melbourne Hospital and The Walter and Eliza Hall Institute of Medical Research, Melbourne, Victoria, Australia; Sanofi, Vitry, Paris, France; Sanofi, Great Valley, PA; Sanofi, Cambridge, MA; University Hospital Gasthuisberg, Catholic University of Leuven, Leuven, Belgium; Erasmus University Medical Center, Rotterdam, Netherlands
| | - X Pivot
- 1Institut Curie, Paris, Cedex 05, France; Université de Bordeaux, Bordeaux, INSERM, France; Hospital Clínico Universitario Virgen de la Victoria, Málaga, Spain; Institut Jules Bordet, Centre des Tumeurs de l'Université Libre de Bruxelles, Brussells, Belgium; Centre Georges François Leclerc, Dijon, France; University Hospital Jean Minjoz, Besançon, France; University Paris VI, Paris, France; Erasmus University Medical Center, Daniel den Hoed Cancer Center, Rotterdam, Netherlands; hSR - San Raffaele, Milan, Italy; The Royal Melbourne Hospital and The Walter and Eliza Hall Institute of Medical Research, Melbourne, Victoria, Australia; Sanofi, Vitry, Paris, France; Sanofi, Great Valley, PA; Sanofi, Cambridge, MA; University Hospital Gasthuisberg, Catholic University of Leuven, Leuven, Belgium; Erasmus University Medical Center, Rotterdam, Netherlands
| | - J Gligorov
- 1Institut Curie, Paris, Cedex 05, France; Université de Bordeaux, Bordeaux, INSERM, France; Hospital Clínico Universitario Virgen de la Victoria, Málaga, Spain; Institut Jules Bordet, Centre des Tumeurs de l'Université Libre de Bruxelles, Brussells, Belgium; Centre Georges François Leclerc, Dijon, France; University Hospital Jean Minjoz, Besançon, France; University Paris VI, Paris, France; Erasmus University Medical Center, Daniel den Hoed Cancer Center, Rotterdam, Netherlands; hSR - San Raffaele, Milan, Italy; The Royal Melbourne Hospital and The Walter and Eliza Hall Institute of Medical Research, Melbourne, Victoria, Australia; Sanofi, Vitry, Paris, France; Sanofi, Great Valley, PA; Sanofi, Cambridge, MA; University Hospital Gasthuisberg, Catholic University of Leuven, Leuven, Belgium; Erasmus University Medical Center, Rotterdam, Netherlands
| | - A Jäger
- 1Institut Curie, Paris, Cedex 05, France; Université de Bordeaux, Bordeaux, INSERM, France; Hospital Clínico Universitario Virgen de la Victoria, Málaga, Spain; Institut Jules Bordet, Centre des Tumeurs de l'Université Libre de Bruxelles, Brussells, Belgium; Centre Georges François Leclerc, Dijon, France; University Hospital Jean Minjoz, Besançon, France; University Paris VI, Paris, France; Erasmus University Medical Center, Daniel den Hoed Cancer Center, Rotterdam, Netherlands; hSR - San Raffaele, Milan, Italy; The Royal Melbourne Hospital and The Walter and Eliza Hall Institute of Medical Research, Melbourne, Victoria, Australia; Sanofi, Vitry, Paris, France; Sanofi, Great Valley, PA; Sanofi, Cambridge, MA; University Hospital Gasthuisberg, Catholic University of Leuven, Leuven, Belgium; Erasmus University Medical Center, Rotterdam, Netherlands
| | - L Gianni
- 1Institut Curie, Paris, Cedex 05, France; Université de Bordeaux, Bordeaux, INSERM, France; Hospital Clínico Universitario Virgen de la Victoria, Málaga, Spain; Institut Jules Bordet, Centre des Tumeurs de l'Université Libre de Bruxelles, Brussells, Belgium; Centre Georges François Leclerc, Dijon, France; University Hospital Jean Minjoz, Besançon, France; University Paris VI, Paris, France; Erasmus University Medical Center, Daniel den Hoed Cancer Center, Rotterdam, Netherlands; hSR - San Raffaele, Milan, Italy; The Royal Melbourne Hospital and The Walter and Eliza Hall Institute of Medical Research, Melbourne, Victoria, Australia; Sanofi, Vitry, Paris, France; Sanofi, Great Valley, PA; Sanofi, Cambridge, MA; University Hospital Gasthuisberg, Catholic University of Leuven, Leuven, Belgium; Erasmus University Medical Center, Rotterdam, Netherlands
| | - G Lindeman
- 1Institut Curie, Paris, Cedex 05, France; Université de Bordeaux, Bordeaux, INSERM, France; Hospital Clínico Universitario Virgen de la Victoria, Málaga, Spain; Institut Jules Bordet, Centre des Tumeurs de l'Université Libre de Bruxelles, Brussells, Belgium; Centre Georges François Leclerc, Dijon, France; University Hospital Jean Minjoz, Besançon, France; University Paris VI, Paris, France; Erasmus University Medical Center, Daniel den Hoed Cancer Center, Rotterdam, Netherlands; hSR - San Raffaele, Milan, Italy; The Royal Melbourne Hospital and The Walter and Eliza Hall Institute of Medical Research, Melbourne, Victoria, Australia; Sanofi, Vitry, Paris, France; Sanofi, Great Valley, PA; Sanofi, Cambridge, MA; University Hospital Gasthuisberg, Catholic University of Leuven, Leuven, Belgium; Erasmus University Medical Center, Rotterdam, Netherlands
| | - N Pham
- 1Institut Curie, Paris, Cedex 05, France; Université de Bordeaux, Bordeaux, INSERM, France; Hospital Clínico Universitario Virgen de la Victoria, Málaga, Spain; Institut Jules Bordet, Centre des Tumeurs de l'Université Libre de Bruxelles, Brussells, Belgium; Centre Georges François Leclerc, Dijon, France; University Hospital Jean Minjoz, Besançon, France; University Paris VI, Paris, France; Erasmus University Medical Center, Daniel den Hoed Cancer Center, Rotterdam, Netherlands; hSR - San Raffaele, Milan, Italy; The Royal Melbourne Hospital and The Walter and Eliza Hall Institute of Medical Research, Melbourne, Victoria, Australia; Sanofi, Vitry, Paris, France; Sanofi, Great Valley, PA; Sanofi, Cambridge, MA; University Hospital Gasthuisberg, Catholic University of Leuven, Leuven, Belgium; Erasmus University Medical Center, Rotterdam, Netherlands
| | - Y Su
- 1Institut Curie, Paris, Cedex 05, France; Université de Bordeaux, Bordeaux, INSERM, France; Hospital Clínico Universitario Virgen de la Victoria, Málaga, Spain; Institut Jules Bordet, Centre des Tumeurs de l'Université Libre de Bruxelles, Brussells, Belgium; Centre Georges François Leclerc, Dijon, France; University Hospital Jean Minjoz, Besançon, France; University Paris VI, Paris, France; Erasmus University Medical Center, Daniel den Hoed Cancer Center, Rotterdam, Netherlands; hSR - San Raffaele, Milan, Italy; The Royal Melbourne Hospital and The Walter and Eliza Hall Institute of Medical Research, Melbourne, Victoria, Australia; Sanofi, Vitry, Paris, France; Sanofi, Great Valley, PA; Sanofi, Cambridge, MA; University Hospital Gasthuisberg, Catholic University of Leuven, Leuven, Belgium; Erasmus University Medical Center, Rotterdam, Netherlands
| | - G Gao
- 1Institut Curie, Paris, Cedex 05, France; Université de Bordeaux, Bordeaux, INSERM, France; Hospital Clínico Universitario Virgen de la Victoria, Málaga, Spain; Institut Jules Bordet, Centre des Tumeurs de l'Université Libre de Bruxelles, Brussells, Belgium; Centre Georges François Leclerc, Dijon, France; University Hospital Jean Minjoz, Besançon, France; University Paris VI, Paris, France; Erasmus University Medical Center, Daniel den Hoed Cancer Center, Rotterdam, Netherlands; hSR - San Raffaele, Milan, Italy; The Royal Melbourne Hospital and The Walter and Eliza Hall Institute of Medical Research, Melbourne, Victoria, Australia; Sanofi, Vitry, Paris, France; Sanofi, Great Valley, PA; Sanofi, Cambridge, MA; University Hospital Gasthuisberg, Catholic University of Leuven, Leuven, Belgium; Erasmus University Medical Center, Rotterdam, Netherlands
| | - D Mery-Mignard
- 1Institut Curie, Paris, Cedex 05, France; Université de Bordeaux, Bordeaux, INSERM, France; Hospital Clínico Universitario Virgen de la Victoria, Málaga, Spain; Institut Jules Bordet, Centre des Tumeurs de l'Université Libre de Bruxelles, Brussells, Belgium; Centre Georges François Leclerc, Dijon, France; University Hospital Jean Minjoz, Besançon, France; University Paris VI, Paris, France; Erasmus University Medical Center, Daniel den Hoed Cancer Center, Rotterdam, Netherlands; hSR - San Raffaele, Milan, Italy; The Royal Melbourne Hospital and The Walter and Eliza Hall Institute of Medical Research, Melbourne, Victoria, Australia; Sanofi, Vitry, Paris, France; Sanofi, Great Valley, PA; Sanofi, Cambridge, MA; University Hospital Gasthuisberg, Catholic University of Leuven, Leuven, Belgium; Erasmus University Medical Center, Rotterdam, Netherlands
| | - R Paridaens
- 1Institut Curie, Paris, Cedex 05, France; Université de Bordeaux, Bordeaux, INSERM, France; Hospital Clínico Universitario Virgen de la Victoria, Málaga, Spain; Institut Jules Bordet, Centre des Tumeurs de l'Université Libre de Bruxelles, Brussells, Belgium; Centre Georges François Leclerc, Dijon, France; University Hospital Jean Minjoz, Besançon, France; University Paris VI, Paris, France; Erasmus University Medical Center, Daniel den Hoed Cancer Center, Rotterdam, Netherlands; hSR - San Raffaele, Milan, Italy; The Royal Melbourne Hospital and The Walter and Eliza Hall Institute of Medical Research, Melbourne, Victoria, Australia; Sanofi, Vitry, Paris, France; Sanofi, Great Valley, PA; Sanofi, Cambridge, MA; University Hospital Gasthuisberg, Catholic University of Leuven, Leuven, Belgium; Erasmus University Medical Center, Rotterdam, Netherlands
| | - J Verweij
- 1Institut Curie, Paris, Cedex 05, France; Université de Bordeaux, Bordeaux, INSERM, France; Hospital Clínico Universitario Virgen de la Victoria, Málaga, Spain; Institut Jules Bordet, Centre des Tumeurs de l'Université Libre de Bruxelles, Brussells, Belgium; Centre Georges François Leclerc, Dijon, France; University Hospital Jean Minjoz, Besançon, France; University Paris VI, Paris, France; Erasmus University Medical Center, Daniel den Hoed Cancer Center, Rotterdam, Netherlands; hSR - San Raffaele, Milan, Italy; The Royal Melbourne Hospital and The Walter and Eliza Hall Institute of Medical Research, Melbourne, Victoria, Australia; Sanofi, Vitry, Paris, France; Sanofi, Great Valley, PA; Sanofi, Cambridge, MA; University Hospital Gasthuisberg, Catholic University of Leuven, Leuven, Belgium; Erasmus University Medical Center, Rotterdam, Netherlands
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Pham N, Sivapatham T, Hussain MS, Bhalla T, Masaryk TJ, Hui FK. Particle embolization of the bilateral superior and inferior alveolar arteries for life threatening dental socket hemorrhage. J Neurointerv Surg 2011; 4:e20. [PMID: 21990507 DOI: 10.1136/neurintsurg-2011-010044] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
Particle embolization for epistaxis and intra-oral hemorrhage are performed on an as needed basis by neurointerventionalists. A case is presented of massive oral hemorrhage associated with end stage liver disease coagulopathy after tooth extraction of bilateral maxillary and mandibular molars. A man in his fifties with end stage liver disease who presented for evaluation of a syncopal episode was determined to be in hemorrhagic shock from 2 days of persistent oral bleeding after elective tooth extractions. Conservative management with multiple blood transfusion products, packing and vasoconstrictive spray was ineffective. Microcatheter angiograms of the alveolar arteries demonstrated blood and contrast pooling within the sockets of the extracted teeth. Selection of the bilateral supplying alveolar and inferior alveolar artery branches was achieved followed by polyvinyl alcohol particle embolization (250-355 μm). Polyvinyl alcohol particle embolization of dental socket hemorrhages is technically feasible and effective.
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Affiliation(s)
- Nancy Pham
- Cerebrovascular Center, Neurological Institute, Cleveland Clinic Foundation, Cleveland, Ohio, USA
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Lautrette A, Pham N, Tixier V, Ait-Hssain A, Heng AE, Deteix P, Souweine B. L’hyperfiltration glomérulaire en réanimation existe-t-elle ? Nephrol Ther 2011. [DOI: 10.1016/j.nephro.2011.07.216] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Pham N, Fazio V, Cucullo L, Teng Q, Biberthaler P, Bazarian JJ, Janigro D. Extracranial sources of S100B do not affect serum levels. PLoS One 2010; 5:e12691. [PMID: 20844757 PMCID: PMC2937027 DOI: 10.1371/journal.pone.0012691] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2010] [Accepted: 08/11/2010] [Indexed: 02/04/2023] Open
Abstract
S100B, established as prevalent protein of the central nervous system, is a peripheral biomarker for blood-brain barrier disruption and often also a marker of brain injury. However, reports of extracranial sources of S100B, especially from adipose tissue, may confound its interpretation in the clinical setting. The objective of this study was to characterize the tissue specificity of S100B and assess how extracranial sources of S100B affect serum levels. The extracranial sources of S100B were determined by analyzing nine different types of human tissues by ELISA and Western blot. In addition, brain and adipose tissue were further analyzed by mass spectrometry. A study of 200 subjects was undertaken to determine the relationship between body mass index (BMI) and S100B serum levels. We also measured the levels of S100B homo- and heterodimers in serum quantitatively after blood-brain barrier disruption. Analysis of human tissues by ELISA and Western blot revealed variable levels of S100B expression. By ELISA, brain tissue expressed the highest S100B levels. Similarly, Western blot measurements revealed that brain tissue expressed high levels of S100B but comparable levels were found in skeletal muscle. Mass spectrometry of brain and adipose tissue confirmed the presence of S100B but also revealed the presence of S100A1. The analysis of 200 subjects revealed no statistically significant relationship between BMI and S100B levels. The main species of S100B released from the brain was the B-B homodimer. Our results show that extracranial sources of S100B do not affect serum levels. Thus, the diagnostic value of S100B and its negative predictive value in neurological diseases in intact subjects (without traumatic brain or bodily injury from accident or surgery) are not compromised in the clinical setting.
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Affiliation(s)
- Nancy Pham
- Cleveland Clinic Lerner College of Medicine of Case Western Reserve University, Cleveland Clinic Foundation, Cleveland, Ohio, United States of America
| | - Vincent Fazio
- Department of Cell Biology, Cleveland Clinic Foundation, Cleveland, Ohio, United States of America
| | - Luca Cucullo
- Department of Cell Biology, Cleveland Clinic Foundation, Cleveland, Ohio, United States of America
| | - Qingshan Teng
- Neurological Surgery, Cleveland Clinic Foundation, Cleveland, Ohio, United States of America
| | - Peter Biberthaler
- Surgical Department Munich Central, Ludwig-Maximilians-Universität Munich, Munich, Germany
| | - Jeffrey J. Bazarian
- Department of Emergency Medicine, University of Rochester School of Medicine, Rochester, New York, United States of America
| | - Damir Janigro
- Cleveland Clinic Lerner College of Medicine of Case Western Reserve University, Cleveland Clinic Foundation, Cleveland, Ohio, United States of America
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John T, Kohler D, Yanagawa N, Pintilie M, Li M, Panchal D, Pham N, Der S, Shepherd FA, Tsao MS. Correlation of engraftment, mutation status, and response to chemotherapy in primary tumor xenograft models of NSCLC. J Clin Oncol 2010. [DOI: 10.1200/jco.2010.28.15_suppl.10517] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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Abstract
Aggregation of the normal cellular prion protein, PrP, is important in the pathogenesis of prion disease. PrP binds glycosaminoglycan (GAG) and divalent cations, such as Cu(2+) and Zn(2+). Here, we report our findings that GAG and Cu(2+) promote the aggregation of recombinant human PrP (rPrP). The normal cellular prion protein has five octapeptide repeats. In the presence of either GAG or Cu(2+), mutant rPrPs with eight or ten octapeptide repeats are more aggregation prone, exhibit faster kinetics and form larger aggregates than wild-type PrP. When the GAG-binding motif, KKRPK, is deleted the effect of GAG but not that of Cu(2+) is abolished. By contrast, when the Cu(2+)-binding motif, the octapeptide-repeat region, is deleted, neither GAG nor Cu(2+) is able to promote aggregation. Therefore, the octapeptide-repeat region is critical in the aggregation of rPrP, irrespective of the promoting ligand. Furthermore, aggregation of rPrP in the presence of GAG is blocked with anti-PrP mAbs, whereas none of the tested anti-PrP mAbs block Cu(2+)-promoted aggregation. However, a mAb that is specific for an epitope at the N-terminus enhances aggregation in the presence of either GAG or Cu(2+). Therefore, although binding of either GAG or Cu(2+) promotes the aggregation of rPrP, their aggregation processes are different, suggesting multiple pathways of rPrP aggregation.
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Affiliation(s)
- Shuiliang Yu
- Department of Pathology, Case Western Reserve University, Cleveland, OH 44106-7288, USA
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Paye-Jaouen A, Pham N, Azoulay R, El Ghoneimi A. SFCP-P04 – Urologie – Traitement endoscopique des urétérocèles ectopiques sur duplication : mythe ou réalité ? Arch Pediatr 2008. [DOI: 10.1016/s0929-693x(08)72008-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Yin S, Pham N, Yu S, Li C, Wong P, Chang B, Kang SC, Biasini E, Tien P, Harris DA, Sy MS. Human prion proteins with pathogenic mutations share common conformational changes resulting in enhanced binding to glycosaminoglycans. Proc Natl Acad Sci U S A 2007; 104:7546-51. [PMID: 17456603 PMCID: PMC1863438 DOI: 10.1073/pnas.0610827104] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.9] [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: 11/18/2022] Open
Abstract
Mutation in the prion gene PRNP accounts for 10-15% of human prion diseases. However, little is known about the mechanisms by which mutant prion proteins (PrPs) cause disease. Here we investigated the effects of 10 different pathogenic mutations on the conformation and ligand-binding activity of recombinant human PrP (rPrP). We found that mutant rPrPs react more strongly with N terminus-specific antibodies, indicative of a more exposed N terminus. The N terminus of PrP contains a glycosaminoglycan (GAG)-binding motif. Binding of GAG is important in prion disease. Accordingly, all mutant rPrPs bind more GAG, and GAG promotes the aggregation of mutant rPrPs more efficiently than wild-type recombinant normal cellular PrP (rPrP(C)). Furthermore, point mutations in PRNP also cause conformational changes in the region between residues 109 and 136, resulting in the exposure of a second, normally buried, GAG-binding motif. Importantly, brain-derived PrP from transgenic mice, which express a pathogenic mutant with nine extra octapeptide repeats, also binds more strongly to GAG than wild-type PrP(C). Thus, several rPrPs with distinct pathogenic mutations have common conformational changes, which enhance binding to GAG. These changes may contribute to the pathogenesis of inherited prion diseases.
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Affiliation(s)
- Shaoman Yin
- *Department of Pathology, School of Medicine, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, OH 44106
| | - Nancy Pham
- Cleveland Clinic Lerner College of Medicine of Case Western Reserve University, Cleveland Clinic Research Foundation, 9500 Euclid Avenue, Cleveland, OH 44195
| | - Shuiliang Yu
- *Department of Pathology, School of Medicine, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, OH 44106
| | - Chaoyang Li
- *Department of Pathology, School of Medicine, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, OH 44106
| | - Poki Wong
- *Department of Pathology, School of Medicine, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, OH 44106
| | - Binggong Chang
- *Department of Pathology, School of Medicine, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, OH 44106
| | - Shin-Chung Kang
- *Department of Pathology, School of Medicine, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, OH 44106
| | - Emiliano Biasini
- Department of Cell Biology and Physiology, Washington University School of Medicine, 660 South Euclid Avenue, St. Louis, MO 63110; and
| | - Po Tien
- Institute of Microbiology, Chinese Academy of Sciences, Beijing 10080, China
| | - David A. Harris
- Department of Cell Biology and Physiology, Washington University School of Medicine, 660 South Euclid Avenue, St. Louis, MO 63110; and
| | - Man-Sun Sy
- *Department of Pathology, School of Medicine, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, OH 44106
- To whom correspondence should be addressed at:
School of Medicine, Case Western Reserve University, Room 5131, Wolstein Research Building, 2103 Cornell Road, Cleveland, OH 44106-7288. E-mail:
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Stratton MJ, Cheung K, Pham N, Miller A. PERMEATION IS A MUCH LARGER DETERMINANT OF BLOCK OF HERG BY QUINIDINE AND CISAPRIDE THAN INACTIVATION. J Investig Med 2007. [DOI: 10.1097/00042871-200701010-00062] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Pichurin P, Pham N, David CS, Rapoport B, McLachlan SM. HLA-DR3 transgenic mice immunized with adenovirus encoding the thyrotropin receptor: T cell epitopes and functional analysis of the CD40 Graves' polymorphism. Thyroid 2006; 16:1221-7. [PMID: 17199432 DOI: 10.1089/thy.2006.16.1221] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The major histocompatibility (MHC) molecule HLA-DR3 is a susceptibility gene for Graves' disease (GD) in Caucasians. Mice lacking murine MHC and expressing human HLA-DR3 develop thyrotropin receptor (TSHR) antibodies and sometimes hyperthyroidism after vaccination with TSHR-DNA. MHC molecules present peptides processed from antigens to T cells. Therefore, we used DR3-transgenic mice to investigate recognition of TSHR ectodomain peptides. After immunization with TSHR A-subunit adenovirus (A-subunit-Ad) but not control-adenovirus (Control-Ad), splenocytes from DR3 mice responded to A-subunit protein in culture by producing interferon-gamma (IFN-gamma). When challenged with 29 overlapping TSHR peptides, splenocytes from A-subunit-Ad- or Control-Ad-immunized mice responded to several peptides. However, in splenocytes from A-subunit-Ad but not Control-Ad mice, a peptide containing TSHR residues 142-161 induced significantly more IFN-gamma than the same splenocytes in medium alone. Immunized DR3 mice also permitted testing the TSHR-specific function of the CD40 single nucleotide polymorphism (C vs. T) associated with GD. Of three human DR3 human Epstein-Barr virus lines (EBVL), two had C in both alleles (CC) and one was CT. However, these EBVL presented peptides poorly and there was no difference between CC vs. CT EBVL in peptide presentation to splenocytes from immunized mice. A peptide corresponding to residues 145-163 is one of seven suggested to be important in GD based on HLA-binding affinities, T-epitope algorithms, and human studies. Consequently, as in human GD, TSHR amino acids 142-161 appear to include a major T cell epitope in HLA-DR3 transgenic mice immunized with A-subunit-Ad.
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Affiliation(s)
- Pavel Pichurin
- Autoimmune Disease Unit, Cedars-Sinai Research Institute and UCLA School of Medicine, Los Angeles, California, USA
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40
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Pichurin PN, Chen CR, Chazenbalk GD, Aliesky H, Pham N, Rapoport B, McLachlan SM. Targeted expression of the human thyrotropin receptor A-subunit to the mouse thyroid: insight into overcoming the lack of response to A-subunit adenovirus immunization. J Immunol 2006; 176:668-76. [PMID: 16365463 DOI: 10.4049/jimmunol.176.1.668] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The thyrotropin receptor (TSHR), the major autoantigen in Graves' disease, is posttranslationally modified by intramolecular cleavage to form disulfide-linked A- and B-subunits. Because Graves' hyperthyroidism is preferentially induced in BALB/c mice using adenovirus encoding the free A-subunit rather than full-length human TSHR, the shed A-subunit appears to drive the disease-associated autoimmune response. To further investigate this phenomenon, we generated transgenic mice with the human A-subunit targeted to the thyroid. Founder transgenic mice had normal thyroid function and were backcrossed to BALB/c. The A-subunit mRNA expression was confirmed in thyroid tissue. Unlike wild-type littermates, transgenic mice immunized with low-dose A-subunit adenovirus failed to develop TSHR Abs, hyperthyroidism, or splenocyte responses to TSHR Ag. Conventional immunization with A-subunit protein and adjuvants induced TSHR Abs lacking the characteristics of human autoantibodies. Unresponsiveness was partially overcome using high-dose, full-length human TSHR adenovirus. Although of low titer, these induced Abs recognized the N terminus of the A-subunit, and splenocytes responded to A-subunit peptides. Therefore, "non-self" regions in the B-subunit did not contribute to inducing responses. Indeed, transgenic mice immunized with high-dose A-subunit adenovirus developed TSHR Abs with thyrotropin-binding inhibitory activity, although at lower titers than wild-type littermates, suggesting down-regulation in the transgenic mice. In conclusion, in mice expressing a human A-subunit transgene in the thyroid, non-self human B-subunit epitopes are not necessary to induce responses to the A-subunit. Our findings raise the possibility that autoimmunity to the TSHR in humans may not involve epitopes on a cross-reacting protein, but rather, strong adjuvant signals provided in bystander immune responses.
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Affiliation(s)
- Pavel N Pichurin
- Autoimmune Disease Unit, Cedars-Sinai Research Institute, and University of California School of Medicine, Los Angeles, CA 90095, USA
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Guo J, McLachlan SM, Pichurin PN, Chen CR, Pham N, Aliesky HA, David CS, Rapoport B. Relationship between thyroid peroxidase T cell epitope restriction and antibody recognition of the autoantibody immunodominant region in human leukocyte antigen DR3 transgenic mice. Endocrinology 2005; 146:4961-7. [PMID: 16081633 DOI: 10.1210/en.2005-0760] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
We investigated the relationship between thyroid peroxidase (TPO) antibody and T lymphocyte epitopes in TPO-adenovirus (TPO-Ad) immunized BALB/c mice and mice transgenic for the human class II molecule DR3 associated with human thyroid autoimmunity. TPO autoantibodies are largely restricted to an immunodominant region (IDR). BALB/c mice immunized with fewer (10(7) vs. 10(9)) TPO-Ad particles developed TPO antibodies with lower titers that displayed greater restriction to the IDR. However, as with higher-dose TPO-Ad immunization, T cell epitopes (assessed by splenocyte interferon-gamma response to TPO in vitro) were highly diverse and variable in different animals. In contrast, DR3 mice immunized the higher TPO-Ad dose (10(9) particles) had high TPO antibody levels that showed relative focus on the IDR. Moreover, T cell epitopes recognized by splenocytes from DR3 mice showed greater restriction than BALB/c mice. Antibody affinities for TPO were higher in DR3 than in BALB/c mice. The present study indicates that weak TPO-Ad immunization of BALB/c mice (with consequent low TPO antibody titers) is required for enhanced IDR focus yet is not associated with T cell epitopic restriction. Humanized DR3 transgenic mice, despite stronger TPO-Ad immunization, develop higher titer TPO antibodies that do focus on the autoantibody IDR with T cells that recognize a more limited range of TPO peptides. These data suggest a relationship between major histocompatibility complex class II molecules and the development of antibodies to the IDR, a feature of human thyroid autoimmunity.
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Affiliation(s)
- Jin Guo
- Autoimmune Disease Unit, Cedars-Sinai Medical Center, 8700 Beverly Boulevard, Suite B-131, Los Angeles, California 90048, USA
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Abstract
Cyclic nucleotide ras GEF (CNrasGEF) is a guanine-nucleotide exchange factor previously isolated in a screen for Nedd4-WW domain interacting proteins (Pham, N., Cheglakov, I., Koch, C. A., de Hoog, C. L., Moran, M. F., and Rotin, D. (2000) Curr. Biol. 10, 555-558). It activates Ras in a cAMP-dependent manner and Rap-1 independent of cAMP. Here we show that CNrasGEF is a likely substrate of the ubiquitin protein ligase Nedd4. CNrasGEF possesses two PY motifs at its C terminus that are responsible for binding to Nedd4 in vitro. Moreover, Nedd4 and CNrasGEF co-immunoprecipitate from 293T cells expressing ectopic CNrasGEF and endogenous Nedd4, and this co-immunoprecipitation is abrogated in PY motif-mutated CNrasGEF (CNrasGEFDelta2PY). CNrasGEF is ubiquitinated in cells, and this ubiquitination is augmented upon overexpression of wt-Nedd4 but is inhibited in cells overexpressing a catalytically inactive Nedd4 (Nedd4(CS)) or in cells expressing CNrasGEFDelta2PY, which cannot bind Nedd4. Moreover, pulse-chase experiments have demonstrated that the half-life of CNrasGEF is reduced 5-fold (from approximately 10 to approximately 2 h) in cells co-expressing Nedd4 with CNrasGEF but not with CNrasGEFDelta2PY (t(0.5) approximately 14 h). CNrasGEF is also stabilized in cells co-expressing Nedd4(CS) or following treatment with lactacystin, indicating proteasomal degradation of this protein. Deletion/mutation of the CDC25 domain to abrogate Ras (or Rap-1) binding leads to impaired ubiquitination of CNrasGEF, suggesting that such binding is critical for ubiquitination. Treatment of cells with the cAMP analogue 8-bromo-cAMP does not affect the ability of CNrasGEF to bind Nedd4 nor its level of ubiquitination, suggesting that Ras binding per se and not its activation is the critical step in triggering ubiquitination of CNrasGEF. These results suggest that CNrasGEF is a substrate for Nedd4, which regulates its ubiquitination and stability in cells.
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Affiliation(s)
- N Pham
- Program in Cell Biology, Hospital for Sick Children, University of Toronto, 555 University Ave., Toronto, Ontario M5G 1X8, Canada
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Pham N, Cheglakov I, Koch C, de Hoog C, Moran M, Rotin D. The guanine nucleotide exchange factor CNrasGEF activates Ras in response to cAMP and cGMP. Curr Biol 2000. [DOI: 10.1016/s0960-9822(00)00627-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Abstract
Small GTPase proteins such as Ras are key regulators of cellular proliferation and are activated by guanine nucleotide exchange/releasing factors (GEFs/GRFs). Three classes of Ras GRFs have been identified to date, represented by Sos1/2, Ras-GRF1/2 and Ras-GRP. Here, we describe a novel candidate Ras activator, cyclic nucleotide rasGEF (CNrasGEF), which contains CDC25, Ras exchange motif (REM), Ras-association (RA), PDZ and cNMP (cAMP/cGMP) binding (cNMP-BD) domains, two PY motifs and a carboxy-terminal SxV sequence. CNrasGEF can activate Ras in vitro, and it binds cAMP directly via its cNMP-BD. In cells, CNrasGEF activates Ras in response to elevation of intracellular cAMP or cGMP, or treatment with their analogues 8-Br-cAMP or 8-Br-cGMP, independently of protein kinases A and G (PKA and PKG). This activation is prevented in CNrasGEF lacking its CDC25 domain or cNMP-BD. CNrasGEF can also activate the small GTPase Rap1 in cells, but this activation is constitutive and independent of cAMP. CNrasGEF is expressed mainly in the brain and is localized at the plasma membrane, a localization dependent on the presence of intact PDZ domain but not the SxV sequence. These results suggest that CNrasGEF may directly connect cAMP-generating pathways or cGMP-generating pathways to Ras.
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Affiliation(s)
- N Pham
- Program in Cell Biology, Department of Biochemistry, The Hospital for Sick Children, University of Toronto, Toronto, M5G 1X8, Canada
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Santelli J, Vernon M, Lowry R, Osorio J, DuShaw M, Lancaster MS, Pham N, Song E, Ginn E, Kolbe LJ. Managed care, school health programs, and adolescent health services: opportunities for health promotion. J Sch Health 1998; 68:434-440. [PMID: 9919500 DOI: 10.1111/j.1746-1561.1998.tb06325.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
The rapid expansion of managed care creates opportunities and dilemmas for those involved in school health and adolescent health promotion. Managed care organizations (MCOs), public health agencies, and school and adolescent health providers share certain common goals and priorities including an emphasis on prevention, cost-effectiveness, and quality of care--and a willingness to explore innovative approaches to health promotion and disease prevention. However, MCOs often face conflicting challenges, balancing the goals of cost containment and investment in prevention. In considering support for school health programs, MCOs will be interested in evidence about the effectiveness of services in improving health and/or reducing medical expenditures. Mechanisms for improving prevention efforts within MCOs include quality assurance systems to monitor the performance of health plans, practice guidelines from professional organizations, and the contracting process between payers and health care providers. Development of partnerships between MCOs and schools will be a challenge given competing priorities, variation in managed care arrangements, structural differences between MCOs and schools, and variability in services provided by school health programs.
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Affiliation(s)
- J Santelli
- Division of Adolescent and School Health, Atlanta, GA 30341, USA
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Uyemura K, Demer LL, Castle SC, Jullien D, Berliner JA, Gately MK, Warrier RR, Pham N, Fogelman AM, Modlin RL. Cross-regulatory roles of interleukin (IL)-12 and IL-10 in atherosclerosis. J Clin Invest 1996; 97:2130-8. [PMID: 8621803 PMCID: PMC507288 DOI: 10.1172/jci118650] [Citation(s) in RCA: 332] [Impact Index Per Article: 11.9] [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: 01/31/2023] Open
Abstract
T cell cytokines are known to play a major role in determining protection and pathology in infectious disease. It has recently become clear that IL-12 is a key inducer of the type 1 T cell cytokine pattern characterized by production of IFN-gamma. Conversely, IL-10 down-regulates IL-12 production and type 1 cytokine responses. We have investigated whether IL-12 and IL-10 might be involved in a chronic inflammatory reaction, atherosclerosis. In atherosclerotic plaques, we found strong expression of IFN-gamma but not IL-4 mRNAs as compared to normal arteries. IL-12 p40 mRNA and IL-12 p70 protein were also found to be abundant in atherosclerotic plaques. IL-12 was induced in monocytes in vitro in response to highly oxidized LDL but not minimally modified LDL. The cross-regulatory role of IL-10 was indicated by the expression of IL-10 in some atherosclerotic lesions, and the demonstration that exogenous rIL-10 inhibited LDL-induced IL-12 release. These data suggest that the balance between IL-12 and IL-10 production contributes to the level of immune-mediated tissue injury in atherosclerotsis.
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Affiliation(s)
- K Uyemura
- Department of Medicine, University of California, School of Medicine, Los Angeles, USA
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Ueda T, Wang Z, Pham N, Messing J. Identification of a transcriptional activator-binding element in the 27-kilodalton zein promoter, the -300 element. Mol Cell Biol 1994; 14:4350-9. [PMID: 8007944 PMCID: PMC358806 DOI: 10.1128/mcb.14.7.4350-4359.1994] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [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: 01/28/2023] Open
Abstract
By utilizing a homologous transient-expression system, we have shown that a 58-bp sequence from the gamma-class 27-kDa zein promoter, spanning from -307 to -250 relative to the transcription start site, confers a high level of transcriptional activity on a truncated plant viral promoter. The transcriptional activity mediated by the 58-bp sequence is orientation independent, and it is further enhanced as a result of its multimerization. A similarly high level of transcriptional activity was also observed in protoplasts isolated from leaf tissue-derived maize suspension cells. In vitro binding and DNase I footprinting assays with nuclear protein prepared from cultured endosperm cells revealed the sequence-specific binding of a nuclear factor(s) to a 16-nucleotide sequence present in the 58-bp region. The nuclear factor binding sequence includes the -300 element, a cis-acting element highly conserved among different zein genes and many other cereal storage protein genes. A 23-bp oligonucleotide sequence containing the nuclear factor binding site is sufficient for binding the nuclear factor in vitro. It also confers a high level of transcriptional activity in vivo, but in an orientation-dependent manner. Four nucleotide substitutions in the -300 element drastically reduced binding and transcriptional activation by the nuclear factor. The same nuclear factor is abundant in the developing kernel endosperm and binds to the -300 element region of the 27-kDa or the alpha-class zein promoter. These results suggest that the highly conserved -300 element is involved in the common regulatory mechanisms mediating the coordinated expression of the zein genes.
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Affiliation(s)
- T Ueda
- Waksman Institute, Rutgers University, Piscataway, New Jersey 08855-0759
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