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Marek RJ, Le JT, Hapenciuc G, Philip MA, Chiu J, Block AR, Ben-Porath YS. Incremental Contribution of the Minnesota Multiphasic Personality Inventory - 3 to Predicting One-Year Postoperative Spinal Cord Surgery/Spinal Cord Stimulation Outcomes. J Clin Psychol Med Settings 2024; 31:77-90. [PMID: 37642803 DOI: 10.1007/s10880-023-09971-3] [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] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/10/2023] [Indexed: 08/31/2023]
Abstract
Pre-surgical psychological assessments are becoming common in the United States and are recommended or required prior to surgical/spinal cord stimulator intervention for chronic back pain. Psychological testing is often recommended for these evaluations and the various versions of the Minnesota Multiphasic Personality Inventory (MMPI) have demonstrated utility for predicting outcomes in this setting. This investigation sought to extend that literature with the newest version of the MMPI, the MMPI-3. The sample comprised of 909 patients (50.5% men, 49.5% women) who consented to participating in an outcome study and took the MMPI-3 along with other self-report measures of pain, functional disability, and emotional functioning prior to surgery as part of their pre-surgical psychological assessment. Self-report measures of pain, functional disability, and emotional functioning were administered again one-year following the intervention. MMPI-3 scale scores accounted for up to 9% of additional variance in the outcomes after controlling for pre-surgical measures. Measures of emotional/internalizing dysfunction, somatic dysfunction, and, to a lesser extent, behavioral/externalizing dysfunction contributed the most to the prediction of poorer outcomes.
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Affiliation(s)
- Ryan J Marek
- Department of Psychology and Philosophy, Sam Houston State University, 1905 University Ave, Huntsville, TX, 77340, USA.
| | - Janet T Le
- Department of Primary Care & Clinical Medicine, Sam Houston State University, Conroe, TX, USA
| | - Gabriel Hapenciuc
- Department of Primary Care & Clinical Medicine, Sam Houston State University, Conroe, TX, USA
| | - Michelle A Philip
- Department of Primary Care & Clinical Medicine, Sam Houston State University, Conroe, TX, USA
| | - Josephine Chiu
- Department of Primary Care & Clinical Medicine, Sam Houston State University, Conroe, TX, USA
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Lancette GA, Harmon SM, Brooks D, Bryant R, Chiu J, Graham J, Guilfoyle D, Hill W, Latt T, Noah C, Placencia A, Pratt M, Radle D, Smith A, Solomon H, Staben D, Stern N, Thaker N. Enumeration and Confirmation of Bacillus cereus in Foods: Collaborative Study. J AOAC Int 2020. [DOI: 10.1093/jaoac/63.3.581] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Abstract
A collaborative study was conducted in 15 laboratories to evaluate 2 different techniques for enumerating Bacillus cereus in foods. A direct plating technique using mannitol-egg yolk-polymyxin agar and a most probable number (MPN) technique using trypticase-soy-polymyxin broth were compared for the enumeration of high and low populations of B. cereus in mashed potatoes. The collaborative results showed that the overall mean recovery obtained with the low population level was essentially the same by both techniques. However, the overall mean recovery was significantly higher by the direct plating technique at the high population level. A statistical evaluation of the data also showed that the direct plating technique had better repeatability and reproducibility than did the MFN technique at both the high and low population levels. These results suggest that the MPN technique is suitable for examining foods containing low populations of B. cereus, but that the direct plating technique is preferable for foods that contain a high population of this organism. The confirmatory technique used in the proposed method is reliable for presumptive identification of isolates as B. cereus. The method has been adopted as official first action.
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Affiliation(s)
- Gayle A Lancette
- Food and Drug Administration, Minneapolis Center for Microbiological Investigations, Minneapolis, MN 55401
| | - Stanley M Harmon
- Food and Drug Administration, Minneapolis Center for Microbiological Investigations, Minneapolis, MN 55401
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Povitz M, Bansback N, Fenton M, Almeida F, Ratycz D, Huynh N, Ayas N, Chiu J, Pendharkar S. Workplace and driving consequences of sleepiness in Canadians with obstructive sleep apnea: results of a market research survey. Sleep Med 2019. [DOI: 10.1016/j.sleep.2019.11.860] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Yap Y, Masuda N, Ito Y, Ishikawa T, Kim S, Aruga T, Toyama T, Saeki T, Yamanaka T, Saito M, Watanabe J, Takahashi M, Nakamura S, Inoue K, Suarez-Vizcarra J, He W, Solovieff N, Su F, Chiu J. Biomarker analyses of Asian women with hormone receptor-positive (HR+), HER2-negative (HER2–) advanced breast cancer (ABC) receiving ribociclib (RIB) + endocrine therapy (ET). Ann Oncol 2018. [DOI: 10.1093/annonc/mdy428.001] [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: 11/13/2022] Open
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Yau S, Bettio L, Vetrici M, Truesdell A, Chiu C, Chiu J, Truesdell E, Christie B. Chronic minocycline treatment improves hippocampal neuronal structure, NMDA receptor function, and memory processing in Fmr1 knockout mice. Neurobiol Dis 2018; 113:11-22. [DOI: 10.1016/j.nbd.2018.01.014] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2017] [Revised: 12/18/2017] [Accepted: 01/19/2018] [Indexed: 10/18/2022] Open
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Chiu J, Leung R, Sze H, Teo P, Choi P, Lam TC, Yau T, Cheng P, Cheung FY, Cheung P. Real world data on use of palbociclib in hormone-receptor (ER) positive HER2 negative metastatic breast cancer (MBC) among Asian patients. Ann Oncol 2017. [DOI: 10.1093/annonc/mdx654.024] [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: 11/13/2022] Open
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Yap YS, Ito Y, Bornstein O, Han Y, Samant T, Liu X, Chiu J. Phase Ib study of ribociclib (RIB) + letrozole (LET) in a subset of Asian patients (pts) with hormone receptor-positive (HR+), human epidermal growth factor receptor 2-negative (HER2–) advanced breast cancer (ABC). Ann Oncol 2017. [DOI: 10.1093/annonc/mdx654.002] [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: 11/13/2022] Open
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Sajith S, Wong W, Chiu J, Chiam P. Perceptions of Residents and Non-residents in Psychiatry on Training Needs and Care of Patients with Intellectual Disability and Mental Health Problems: A Study from Singapore. Eur Psychiatry 2017. [DOI: 10.1016/j.eurpsy.2017.01.2036] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Background and ObjectivePsychiatric assessment and care of people with Intellectual Disability (ID) is complex due to their cognitive and communication impairments. Demand for further training in this area by trainees in psychiatry has been well documented. The main of aims of this study were to explore the attitudes and perceptions of psychiatry residents and non-residents (non-trainees) with regards to care of patients with ID as well as their knowledge and training in this area.MethodThe study was conducted as an anonymous survey at the Institute of Mental Health, Singapore. A survey questionnaire developed by the study team was sent to residents and non-residents in psychiatry.ResultsForty-eight out of the 76 questionnaires were returned with a response rate of 63.16%. Twenty-eight participants described themselves as non-residents and the rest were residents. All participants responded that postgraduate training was required in the area of ID and mental health and majority reported that available training was inadequate. Ninety percent of respondents believed that people with ID were vulnerable to exploitation by other patients in the inpatient unit and 94% of respondents believed that people with ID should be managed by a specialist team.ConclusionCurrently residents and non-residents in psychiatry see that training in ID and mental health as well as services for people with ID as inadequate. Efforts should be made to include specialist training in psychiatry of ID in the Singapore psychiatry curriculum to enhance the confidence and expertise of psychiatrists in this field.
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Mohammed M, Chiu J, Henderson D, Koszyca B. Primary intraventricular germinoma in a 27-year-old male. Pathology 2017. [DOI: 10.1016/j.pathol.2016.12.206] [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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Chiu J, Valente KN, Levy NE, Min L, Lenhoff AM, Lee KH. Knockout of a difficult-to-remove CHO host cell protein, lipoprotein lipase, for improved polysorbate stability in monoclonal antibody formulations. Biotechnol Bioeng 2016; 114:1006-1015. [PMID: 27943242 DOI: 10.1002/bit.26237] [Citation(s) in RCA: 127] [Impact Index Per Article: 15.9] [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: 08/07/2016] [Revised: 11/09/2016] [Accepted: 12/04/2016] [Indexed: 12/12/2022]
Abstract
While the majority of host cell protein (HCP) impurities are effectively removed in typical downstream purification processes, a small population of HCPs are particularly challenging. Previous studies have identified HCPs that are challenging for a variety of reasons. Lipoprotein lipase (LPL)-a Chinese hamster ovary (CHO) HCP that functions to hydrolyze esters in triglycerides-was one of ten HCPs identified in previous studies as being susceptible to retention in downstream processing. LPL may degrade polysorbate 80 (PS-80) and polysorbate 20 (PS-20) in final product formulations due to the structural similarity between polysorbates and triglycerides. In this work, recombinant LPL was found to have enzymatic activity against PS-80 and PS-20 in a range of solution conditions that are typical of mAb formulations. LPL knockout CHO cells were created with CRISPR and TALEN technologies and resulting cell culture harvest fluid demonstrated significantly reduced polysorbate degradation without significant impact on cell viability when compared to wild-type samples. Biotechnol. Bioeng. 2017;114: 1006-1015. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Josephine Chiu
- Department of Chemical and Biomolecular Engineering, University of Delaware, Newark, Delaware, 19716.,Delaware Biotechnology Institute, Newark, Delaware, 19711
| | - Kristin N Valente
- Department of Chemical and Biomolecular Engineering, University of Delaware, Newark, Delaware, 19716.,Delaware Biotechnology Institute, Newark, Delaware, 19711
| | - Nicholas E Levy
- Department of Chemical and Biomolecular Engineering, University of Delaware, Newark, Delaware, 19716
| | - Lie Min
- Department of Chemical and Biomolecular Engineering, University of Delaware, Newark, Delaware, 19716.,Delaware Biotechnology Institute, Newark, Delaware, 19711
| | - Abraham M Lenhoff
- Department of Chemical and Biomolecular Engineering, University of Delaware, Newark, Delaware, 19716
| | - Kelvin H Lee
- Department of Chemical and Biomolecular Engineering, University of Delaware, Newark, Delaware, 19716.,Delaware Biotechnology Institute, Newark, Delaware, 19711
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Yau S, Bostrom C, Chiu J, Fontaine C, Sawchuk S, Meconi A, Wortman R, Truesdell E, Truesdell A, Chiu C, Hryciw B, Eadie B, Ghilan M, Christie B. Impaired bidirectional NMDA receptor dependent synaptic plasticity in the dentate gyrus of adult female Fmr1 heterozygous knockout mice. Neurobiol Dis 2016; 96:261-270. [DOI: 10.1016/j.nbd.2016.09.012] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2016] [Revised: 09/07/2016] [Accepted: 09/17/2016] [Indexed: 11/29/2022] Open
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Chiu J, Pierce M, Braunstein S, McDermott M, Sneed P, Ma L. SU-F-T-648: Sharpening Dose Fall-Off Via Beam Number Enhancements For Stereotactic Brain Radiosurgery. Med Phys 2016. [DOI: 10.1118/1.4956833] [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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Ma L, Braunstein S, Chiu J, Sahgal A. SU-F-T-113: Inherent Functional Dependence of Spinal Cord Doses of Variable Irradiated Volumes in Spine SBRT. Med Phys 2016. [DOI: 10.1118/1.4956249] [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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Yau T, Chiu J, Cheung TT. What determines treatment success and future perspectives? Postgrad Med J 2016; 92:123-4. [PMID: 26917775 DOI: 10.1136/postgradmedj-2016-134018] [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: 11/03/2022]
Affiliation(s)
- T Yau
- Department of Medicine, Queen Mary Hospital, Hong Kong, Hong Kong
| | - J Chiu
- Department of Medicine, Queen Mary Hospital, Hong Kong, Hong Kong
| | - T T Cheung
- Department of Surgery, Queen Mary Hospital, Hong Kong, Hong Kong
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Ma L, Chiu J, McDermott M, Sneed P. Prescription Iso-Energy is a Strong Predictor of Symptomatic Adverse Radiation Effect in Stereotactic Radiosurgery of Brain Metastases. Int J Radiat Oncol Biol Phys 2015. [DOI: 10.1016/j.ijrobp.2015.07.096] [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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Chiu J, Ma L. SU-E-T-230: Creating a Large Number of Focused Beams with Variable Patient Head Tilt to Improve Dose Fall-Off for Brain Radiosurgery. Med Phys 2015. [DOI: 10.1118/1.4924591] [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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Wong K, Chiu J, Shen X, Templeton A, Xu W, Chen E, Sherman M, Feld R, Knox J. Impact of Neutrophil-To-Lymphocyte Ratio (Nlr) and Platelet-To-Lymphocyte Ratio (Plr) on Outcomes in Hepatocellular Carcinoma (Hcc) Patients Treated with Sorafenib (Sor). Ann Oncol 2014. [DOI: 10.1093/annonc/mdu334.114] [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: 11/12/2022] Open
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Ma L, Perez-Andujar A, Chiu J, McGuinness C. SU-E-T-563: A Fast and Quantative Picket-Fence Test of a Submillimeter Patient Positioning System for Stereotactic Radiosurgery. Med Phys 2014. [DOI: 10.1118/1.4888898] [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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Zhang Q, Leung R, Wong H, Chiu J, Chu K, Poon J, Epstein R, Kwong Y, Yau T. P9 Comparison of cetuximab and bevacizumab as first-line treatment in KRAS wild type advanced colorectal cancer patients: a retrospective analysis. Eur J Cancer 2014. [DOI: 10.1016/s0959-8049(14)70040-1] [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: 11/17/2022]
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Bansback N, Chiu J, Avina-Zubieta A. AB1369 What is the evidence-based for future policy decisions regarding biologics in sle? A structured review of the literature. Ann Rheum Dis 2013. [DOI: 10.1136/annrheumdis-2012-eular.1363] [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: 11/04/2022]
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Yau T, Chiu J, Tang Y, Chan P, Leung R, Wong H, Fan ST, Poon R. The Use of Secox (Sorafenib, Oxaliplatin, Capcitabine) as the Treatment of Advanced Hepatocellular Carcinoma (HCC): A Single-Center Analysis. Ann Oncol 2012. [DOI: 10.1016/s0923-7534(20)31956-6] [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: 10/25/2022] Open
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Chiu J, Tang V, Chan P, Leung R, Wong H, Poon R, Fan S, Yau T. The Use of Secox (Sorafenib, Oxaliplatin, Capcitabine) as the Treatment of advanced Hepatocellular Carcinoma (HCC) - A Single Center Retrospective Study. Ann Oncol 2012. [DOI: 10.1016/s0923-7534(20)33317-2] [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] Open
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Sun I, Yang S, Kim C, Chiu J. A Dosimetric Comparison of 3D Conformal, IMRT, and VMAT Treatment Plans for Pre-op Patients with Adenocarcinoma of the Upper Rectum, in both Supine and Prone Position: A Pilot Study. J Med Imaging Radiat Sci 2012. [DOI: 10.1016/j.jmir.2012.03.036] [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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Yamada Y, Folkert M, Cohen G, Zaider M, Chiu J, Lis E, Krol G, Bilsky M. PO-390 INTRAOPERATIVE AND PERCUTANEOUS IR-192 BRACHYTHERAPY FOR MULTIPLY IRRADIATED LESIONS OF THE SPINE. Radiother Oncol 2012. [DOI: 10.1016/s0167-8140(12)72356-3] [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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Navia JL, Brozzi N, Chiu J, Blackstone EH, Atik FA, Svensson LG, Gillinov AM, Hanson GL, Al-Ruzzeh S, Feng J, Lytle BW. Endoscopic versus open radial artery harvesting for coronary artery bypass grafting. J Cardiovasc Surg (Torino) 2012; 53:257-263. [PMID: 22456650] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
AIM The radial artery has become the artery of choice after the internal thoracic artery for coronary artery bypass grafting (CABG). This study compares wound healing and arm complications after endoscopic versus open radial artery harvesting for CABG. METHODS From January 2002 to July 2004, 509 patients underwent CABG in which a radial artery conduit was used. Thirty-nine had endoscopic and 470 had conventional open radial artery harvesting. A propensity score was used to obtain 1:3 matching of all endoscopic to 117 open-harvesting patients. Postoperative wound healing using the Hollander scale, local neurologic deficits, wound infection, and pain scores were compared. RESULTS Wound healing: 34 of 39 endoscopic wounds exhibited a perfect Hollander score versus 339 of 470 open-harvest wounds (P=0.01). Wound appearance in particular was better than for open harvesting (P=0.004), with no abnormal step-off borders, irregular contours, or abnormal scar width observed. Neurologic deficits. Three incomplete neurologic deficits were observed after open harvesting (two being distal sensitivity localized in the interspace between the first and second metacarpals); one complete neurologic deficit occurred after endoscopic harvesting, but improved remarkably prior to hospital discharge. Wound infection. Occurrence of wound infection was similar in the two groups (P=0.7), although infection was more severe with open harvesting. Pain: pain score was lower (P=0.006) with endoscopic harvesting. CONCLUSION Compared with conventional open harvesting, endoscopic radial artery harvesting was associated with better wound appearance and less pain. Occurrence of neurologic deficits and wound infection was infrequent in both groups.
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Affiliation(s)
- J L Navia
- Department of Thoracic and Cardiovascular Surgery, Cleveland Clinic, Cleveland, OH 44195, USA.
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Yau T, Wong H, Lau S, Leung R, Chiu J, Wong T, Liang R, Epstein R, Cheung P. 453 Comparison of Clinicopathologic Features of Invasive Lobular Carcinoma of the Breast with or Without Associated Lobular Carcinoma In-situ. Eur J Cancer 2012. [DOI: 10.1016/s0959-8049(12)70518-x] [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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Lee H, Chung T, Ting L, Chen S, Hsiao S, Lai I, Liu E, Chiu J, Tsai J. EGFR Mutations Associated With Superior Intracranial Response and Progression-free Survival After Brain Irradiation in Non-small Cell Lung Cancer With Brain Metastasis. Int J Radiat Oncol Biol Phys 2011. [DOI: 10.1016/j.ijrobp.2011.06.1119] [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: 10/15/2022]
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Kumar A, Chiu J, Miller M, Elsliger M, Deacon A, Wilson I. FAD binding may inhibit a FMN-dependent nitroreductase from Idiomarina loihiensisL2TR. Acta Crystallogr A 2011. [DOI: 10.1107/s0108767311080329] [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: 11/11/2022] Open
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Chiu J, Tang YF, Yao TJ, Wong A, Wong H, Leung RC, Chan P, Cheung TT, Poon RTP, Fan ST, Yau CC. The use of single-agent sorafenib in the treatment of patients with advanced hepatocellular carcinoma with underlying Child-Pugh B liver cirrhosis. J Clin Oncol 2011. [DOI: 10.1200/jco.2011.29.15_suppl.4083] [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: 11/20/2022] Open
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Yau T, Leung RC, Wong H, Chiu J, Chan P, Pang R, Fan ST, Poon RTP. Efficacy and safety of single-agent sunitinib in treating patients with advanced hepatocelluar carcinoma after sorafenib failure: A prospective, open-label, phase II study. J Clin Oncol 2011. [DOI: 10.1200/jco.2011.29.15_suppl.4082] [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: 11/20/2022] Open
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Rappard G, Block J, Miller L, Chiu J, Bini W. O-010 Effective minimally invasive treatment of moderate lumbar spinal stenosis with the superion interspinous spacer. J Neurointerv Surg 2010. [DOI: 10.1136/jnis.2010.003244.10] [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: 11/04/2022]
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Wong H, Yau CC, Yao T, Tang V, Chan P, Chiu J, Fan S, Poon R. Efficacy and tolerability of sorafenib in elderly patients with advanced hepatocellular carcinoma. J Clin Oncol 2010. [DOI: 10.1200/jco.2010.28.15_suppl.e14522] [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: 11/20/2022] Open
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Kim JH, Kamasuta C, Trichavaroj R, Kaewkungwal J, Chantakulkij S, Ratto-Kim S, Eamsila C, Sukwit S, Nitayaphan S, Pitsuttihum P, Michael NL, Chiu J, Rerks-Ngarm S, de Souza MS, Paris RM. OA04-06 LB. Post-infection cellular immune responses in recipients following ALVAC-HIV® + AIDSVAX® B/E prime-boost vaccination in the Thai Phase III Trial. Retrovirology 2009. [PMCID: PMC2767552 DOI: 10.1186/1742-4690-6-s3-o30] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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Poretsky L, Song L, Brillon DJ, Ferrando S, Chiu J, McElhiney M, Ferenczi A, Sison C, Haller I, Rabkin J. Metabolic and hormonal effects of oral DHEA in premenopausal women with HIV infection: a randomized, prospective, placebo-controlled pilot study. Horm Metab Res 2009; 41:244-9. [PMID: 18810712 PMCID: PMC3639496 DOI: 10.1055/s-0028-1087175] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Women with HIV infection use dehydroepiandrosterone (DHEA) because of its potential effects on mood and energy. We examined the effects of DHEA on the hypothalamic-pituitary-adrenal and gonadal axes and on insulin sensitivity. Fifteen HIV-positive women were randomized to receive placebo (6 subjects) or oral DHEA (9 subjects). ACTH-, CRF-, and GnRH-stimulation tests were performed before and after 8 weeks of treatment. DHEA, DHEA-S, dihydrotestosterone, total testosterone, free testosterone, sex hormone-binding globulin, estrone, estradiol, cortisol, insulin, IGF-1, IGFBP-1, IGFBP-3, and adiponectin in plasma or serum were measured. There was a significant increase in DHEA (p<0.004), DHEA-S (p<0.008), total testosterone (p<0.008), dihydrotestosterone (p<0.004), androstenedione (p<0.04), and estrone (p<0.03) from baseline within the DHEA group but not within the placebo group. There was a significant increase in DHEA (p<0.0006), DHEA-S (p<0.032), total testosterone (p<0.01), and dihydrotestosterone (p<0.005) in the DHEA group compared with the placebo group. Oral DHEA produces significant increases in circulating DHEA, DHEA-S, testosterone, DHT, and, possibly, androstenedione and estrone levels in premenopausal women with HIV infection. In the current pilot study these hormone changes did not affect the pituitary or adrenal axis or insulin/IGF indices. Long-term studies with larger groups of patients are needed to confirm these data and to determine their clinical significance.
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Affiliation(s)
- L Poretsky
- Division of Endocrinology, Department of Medicine, Weill Medical College of Cornell University, The New York Presbyterian Hospital, New York, USA.
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Huang S, Yu C, Liu M, Chiu J, Hsu F. SU-GG-T-204: Estimation of Organ Doses in Total Body Irradiation. Med Phys 2008. [DOI: 10.1118/1.2961956] [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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Middlekauff HR, Chiu J, Hamilton MA, Fonarow GC, Maclellan WR, Hage A, Moriguchi J, Patel J. Cyclooxygenase products sensitize muscle mechanoreceptors in humans with heart failure. Am J Physiol Heart Circ Physiol 2008; 294:H1956-62. [PMID: 18296564 DOI: 10.1152/ajpheart.01304.2007] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Prior work in animals and humans suggests that muscle mechanoreceptor control of sympathetic activation [muscle sympathetic nerve activity (MSNA)] during exercise in heart failure (HF) patients is heightened compared with that of healthy humans and that muscle mechanoreceptors are sensitized by metabolic by-products. We sought to determine whether cyclooxygenase products and/or endogenous adenosine, two metabolites of ischemic exercise, sensitize muscle mechanoreceptors during rhythmic handgrip (RHG) exercise in HF patients. Indomethacin, which inhibits the production of prostaglandins, and saline control were infused in 12 HF patients. In a different protocol, aminophylline, which inhibits adenosine receptors, and saline control were infused in 12 different HF patients. MSNA was recorded (microneurography). During exercise following saline, MSNA increased in the first minute of exercise, consistent with baseline heightened mechanoreceptor sensitivity. MSNA continued to increase during 3 min of RHG, indicative that muscle mechanoreceptors are sensitized by ischemia metabolites. Indomethacin, but not aminophylline, markedly attenuated the increase in MSNA during the entire 3 min of low-level rhythmic exercise, consistent with the sensitization of muscle mechanoreceptors by cyclooxygenase products. Interestingly, even the early increase in MSNA was abolished by indomethacin infusion, indicative of the very early generation of cyclooxygenase products after the onset of exercise in HF patients. In conclusion, muscle mechanoreceptors mediate the increase in MSNA during low-level RHG exercise in HF. Cyclooxygenase products, but not endogenous adenosine, play a central role in muscle mechanoreceptor sensitization. Finally, muscle mechanoreceptors in patients with HF have heightened basal sensitivity to mechanical stimuli, which also appears to be mediated by the early generation of cyclooxygenase products, resulting in exaggerated early increases in MSNA.
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Affiliation(s)
- Holly R Middlekauff
- Dept. of Medicine, David Geffen School of Medicine, University of California, Los Angeles, CA 90095, USA.
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Chan K, Perry D, Wolden S, Zelefsky M, Chiu J, Cohen G, Zaider M, Kraus D, Shah J, Lee N. High Dose Rate Intraoperative Radiotherapy for Recurrent Head and Neck Cancer. Int J Radiat Oncol Biol Phys 2007. [DOI: 10.1016/j.ijrobp.2007.07.1624] [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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Chiu J, Chen L, Lee C, Lee P, Usami S, Chien S. MECHANISMS OF INDUCTION OF ENDOTHELIAL CELL E-SELECTIN EXPRESSION BY SMOOTH MUSCLE CELLS AND ITS INHIBITION BY SHEAR STRESS. J Thromb Haemost 2007. [DOI: 10.1111/j.1538-7836.2007.tb01704.x] [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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Baklanov DV, Moodie KM, McCarthy FE, Mandrusov E, Chiu J, Aswonge G, Cheng J, Chow M, Simons M, de Muinck ED. Comparison of transendocardial and retrograde coronary venous intramyocardial catheter delivery systems in healthy and infarcted pigs. Catheter Cardiovasc Interv 2007; 68:416-23. [PMID: 16892441 DOI: 10.1002/ccd.20841] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
UNLABELLED We compared two routes for myocardial delivery of therapeutics, transendocardial (TE) delivery with an intramyocardial injection catheter, and retrograde coronary venous (RCV) delivery with a balloon occlusion catheter in the interventricular vein. METHODS TE and RCV injection of 15 microM, neutron-activatable microspheres was compared in healthy pigs (Group I, n = 3), pigs with a 1-week-old myocardial infarction (MI; group II, n = 5), and pigs with a 2-weeks-old MI (group III, n = 4). The MI was induced by a 1-hr balloon occlusion in the LAD. Both methods were compared in the same animal using different microspheres. The RCV catheter allowed for continuous measurement of distal pressure and 2.5 x 10(6) microspheres were injected in 10 ml at 300 mmHg above balloon occlusion pressure. The TE injections were targeted to the infarct zone and 2.5 x 10(6) microspheres were distributed over 10 injections of 200 microl. RESULTS The retention of microspheres decreased with increase in MI age, but was comparable between devices within the groups. RCV delivery resulted in (14.3 +/- 0.9)% microsphere retention in Group I, (10.3 +/- 0.2)% in Group II, and (6.4 +/- 0.1)% in group III (P < 0.05 versus group I). Microsphere retention after TE was (15.1 +/- 0.7)% in group I, (18.9 +/- 0.6)% in group II, (4.1 +/- 0.1)% in Group III (P < 0.05 versus groups I and II). The RCV catheter delivered primarily to midventricular, antero-septal segments, whereas TE targeted apical areas predominantly. CONCLUSIONS Delivery efficacy was comparable between devices in each group however RCV targeted midventricular areas whereas TE targeted apical areas.
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Affiliation(s)
- D V Baklanov
- Angiogenesis Research Center, Dartmouth Medical School, Hanover, NH, USA
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Abstract
In previous studies, we showed that the spatial and intensive aspects of the SI response to skin flutter stimulation are modified systematically as stimulus amplitude is increased. In this study, we examined the effects of duration of skin flutter stimulation on the spatiotemporal characteristics of the response of SI cortex. Optical intrinsic signal (OIS) imaging was used to study the evoked response in SI of anesthetized squirrel monkeys to 25-Hz sinusoidal vertical skin displacement stimulation. Four stimulus durations were tested (0.5, 1.0, 2.0, and 5.0 s); all stimuli were delivered to a discrete site on the glabrous skin of the contralateral forelimb. Skin stimulation evoked a prominent increase in absorbance within the forelimb regions in SI of the contralateral hemisphere. Responses to brief (0.5 s) stimuli were weaker and spatially more extensive than responses to longer duration stimuli (1.0, 2.0, and 5.0 s). Stimuli >or=1 s in duration suppressed responses to below background levels (decreased absorbance) in regions that surrounded the maximally activated region. The magnitude of the suppression in the surrounding regions was nonuniform and usually was strongest medial and posterior to the maximally activated region. The results show that sustained (>or=1.0 s) stimulation decreases the spatial extent of the responding SI cortical population. Registration of the optical responses with the previously documented SI topographical organization strongly suggests that the cortical regions that undergo the strongest suppression represent skin sites that are normally co-stimulated during tactile exploration.
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Affiliation(s)
- S B Simons
- Department of Biomedical Engineering, University of North Carolina, Chapel Hill, NC 27599, USA
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Abstract
HMG-CoA (3-hydroxy-3-methylglutaryl-CoA) reductase inhibitors (statins) have been shown to reduce serum cholesterol and cardiovascular morbidity and mortality. The mechanisms of these beneficial effects are reviewed. Altered inflammatory responses and improved endothelial function mediated by statins are thought to be, in part, responsible for the reduction in cardiovascular events. It has not been well established whether statins confer similar benefits to the kidney. In this review, we critically consider the available data whereby dyslipidemia mediates renal dysfunction by modulating the inflammatory response to diverse cytokines. We also review the emerging database suggesting that statins may modulate renal dysfunction by altering the response of the kidney to dyslipidemia, particularly in patients with end-stage renal disease (ESRD) and post-kidney transplant.
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Affiliation(s)
- Vito M Campese
- Division of Nephrology and Hypertension Center, Keck School of Medicine, USC, 1200 North State Street, Los Angeles, CA 90033, USA.
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Middlekauff HR, Chiu J, Hamilton MA, Fonarow GC, Maclellan WR, Hage A, Moriguchi J, Patel J. Muscle mechanoreceptor sensitivity in heart failure. Am J Physiol Heart Circ Physiol 2004; 287:H1937-43. [PMID: 15475527 DOI: 10.1152/ajpheart.00330.2004] [Citation(s) in RCA: 86] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Prior work in animals suggests that muscle mechanoreceptor control of sympathetic activation (MSNA) during exercise in heart failure (HF) is heightened and that muscle mechanoreceptors are sensitized by metabolic by-products. We sought to determine whether 1) muscle mechanoreceptor control of MSNA is enhanced in HF patients and 2) lactic acid sensitizes muscle mechanoreceptors during rhythmic handgrip (RHG) exercise in healthy humans and patients with HF. Dichloroacetate (DCA), which reduces the production of lactic acid, or saline control was infused in 12 patients with HF and 13 controls during RHG. MSNA was recorded (microneurography). After saline was administered and during exercise thereafter, MSNA increased earlier in HF compared with controls, consistent with baseline-heightened mechanoreceptor sensitivity. In both HF and controls, MSNA increased during the 3-min exercise protocol, consistent with further sensitization of muscle mechanoreceptors by metabolic by-product(s). During posthandgrip circulatory arrest, MSNA returned rapidly to baseline levels, excluding the muscle metaboreceptors as mediators of the sympathetic excitation during RHG. To isolate muscle mechanoreceptors from central command, we utilized passive exercise in 8 HF and 11 controls, and MSNA was recorded. MSNA increased significantly during passive exercise in HF but not in controls. In conclusion, muscle mechanoreceptors mediate the increase in MSNA during low-level RHG exercise in healthy humans, and this muscle mechanoreceptor control is augmented further in HF. Neither lactate generation nor the fall in pH during RHG plays a central role in muscle mechanoreceptor sensitization. Finally, muscle mechanoreceptors in patients with HF have heightened basal sensitivity to mechanical stimuli resulting in exaggerated early increases in MSNA.
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Affiliation(s)
- Holly R Middlekauff
- Div. of Cardiology, 47-123 CHS, UCLA Dept. of Medicine, 10833 Le Conte Ave., Los Angeles, CA 90095, USA.
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Abstract
Evidence in healthy animals and humans is accumulating that the muscle mechanoreceptors play an important role in mediating sympathetic activation during exercise, especially rhythmic exercise. Furthermore, muscle mechanoreceptors appear to be sensitized acutely during exercise by metabolic by-products, although the identity of these by-products remains unknown. The purpose of this study was to determine whether the metabolic by-products 1) prostaglandins and/or 2) adenosine sensitize muscle mechanoreceptor control of muscle sympathetic nerve activity (MSNA) in normal humans during rhythmic exercise. MSNA was recorded using microneurography. Muscle mechanoreceptors were activated by low-level rhythmic forearm exercise for 3 min. In 16 healthy humans, intra-arterial indomethacin was infused into the exercising arm to inhibit synthesis of cyclooxygenase products. In 18 healthy humans, intra-arterial aminophylline was infused into the exercising arm to block adenosine receptors. During saline control, MSNA increased significantly during exercise. Inhibition of cycloxygenase during exercise dramatically and virtually completely eliminated the reflex sympathetic activation. Inhibition of adenosine receptors with aminophylline had no effect on the sympathetic activation during muscle mechanoreceptor stimulation. In conclusion, muscle mechanoreceptors are sensitized by cyclooxygenase products, but not by adenosine, during 3 min of low-level rhythmic handgrip exercise in healthy humans. Further studies of other metabolic by-products and of patients with enhanced muscle mechanoreceptor sensitivity, such as patients with heart failure, are warranted.
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Affiliation(s)
- Holly R Middlekauff
- Div. of Cardiology, 47-123 CHS, UCLA Dept. of Medicine, 10833 Le Conte Ave., Los Angeles, CA 90095, USA.
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Abstract
Recent studies have implicated reactive oxygen species (ROS) in the pathogenesis of hypertension and activation of the sympathetic nervous system (SNS). Because nitric oxide (NO) exerts a tonic inhibition of central SNS activity, increased production of ROS could enhance inactivation of NO and result in activation of the SNS. To test the hypothesis that ROS may modulate SNS activity, we infused Tempol (4-hydroxy-2,2,6,6-tetramethyl piperidinoxyl), a superoxide dismutase mimetic, or vehicle either intravenously (250 microg x kg(-1) x min(-1)) or in the lateral ventricle (50 microg x kg body wt(-1) x min(-1)), and we determined the effects on blood pressure (BP), norepinephrine (NE) secretion from the posterior hypothalamus (PH) measured by the microdialysis technique, renal sympathetic nerve activity (RSNA) measured by direct microneurography, the abundance of neuronal NO synthase (nNOS)-mRNA in the PH, paraventricular nuclei (PVN), and locus coeruleus (LC) measured by RT-PCR, and the secretion of nitrate/nitrite (NO(x)) in the dialysate collected from the PH of Sprague-Dawley rats. Tempol reduced BP whether infused intravenously or intracerebroventricularly. Tempol reduced NE secretion from the PH and RSNA when infused intracerebroventricularly but raised NE secretion from the PH and RSNA when infused intravenously. The effects of intravenous Tempol on SNS activity were blunted or abolished by sinoaortic denervation. Tempol increased the abundance of nNOS in the PH, PVN, and LC when infused intracerebroventricularly, but it decreased the abundance of nNOS when infused intravenously. When given intracerebroventricularly, Tempol also reduced the concentration of NO(x) in the dialysate collected from the PH. Pretreatment with N(omega)-nitro-l-arginine methyl ester did not abolish the effects of intracerebral Tempol on BP, heart rate, NE secretion from the PH, and RSNA suggesting that the effects of Tempol on SNS activity may be in part dependent and in part independent of NO. In all, these studies support the notion that ROS may raise BP via activation of the SNS. This activation may be mediated in part by downregulation of nNOS and NO production, in part by mechanisms independent of NO. The discrepancy in results between intracerebroventricular and intravenous infusion of Tempol can be best explained by direct inhibitory actions on SNS activity when given intracerebral. By contrast, Tempol may exert direct vasodilation of the peripheral circulation and reflex activation of the SNS when given intravenously.
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Affiliation(s)
- Vito M Campese
- Department of Medicine, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA.
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Lacombe B, Becker D, Hedrich R, DeSalle R, Hollmann M, Kwak JM, Schroeder JI, Le Novère N, Nam HG, Spalding EP, Tester M, Turano FJ, Chiu J, Coruzzi G. The identity of plant glutamate receptors. Science 2001; 292:1486-7. [PMID: 11379626 DOI: 10.1126/science.292.5521.1486b] [Citation(s) in RCA: 117] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
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46
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Oliveira IC, Brenner E, Chiu J, Hsieh MH, Kouranov A, Lam HM, Shin MJ, Coruzzi G. Metabolite and light regulation of metabolism in plants: lessons from the study of a single biochemical pathway. Braz J Med Biol Res 2001; 34:567-75. [PMID: 11323742 DOI: 10.1590/s0100-879x2001000500003] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
We are using molecular, biochemical, and genetic approaches to study the structural and regulatory genes controlling the assimilation of inorganic nitrogen into the amino acids glutamine, glutamate, aspartate and asparagine. These amino acids serve as the principal nitrogen-transport amino acids in most crop and higher plants including Arabidopsis thaliana. We have begun to investigate the regulatory mechanisms controlling nitrogen assimilation into these amino acids in plants using molecular and genetic approaches in Arabidopsis. The synthesis of the amide amino acids glutamine and asparagine is subject to tight regulation in response to environmental factors such as light and to metabolic factors such as sucrose and amino acids. For instance, light induces the expression of glutamine synthetase (GLN2) and represses expression of asparagine synthetase (ASN1) genes. This reciprocal regulation of GLN2 and ASN1 genes by light is reflected at the level of transcription and at the level of glutamine and asparagine biosynthesis. Moreover, we have shown that the regulation of these genes is also reciprocally controlled by both organic nitrogen and carbon metabolites. We have recently used a reverse genetic approach to study putative components of such metabolic sensing mechanisms in plants that may be conserved in evolution. These components include an Arabidopsis homolog for a glutamate receptor gene originally found in animal systems and a plant PII gene, which is a homolog of a component of the bacterial Ntr system. Based on our observations on the biology of both structural and regulatory genes of the nitrogen assimilatory pathway, we have developed a model for metabolic control of the genes involved in the nitrogen assimilatory pathway in plants.
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Affiliation(s)
- I C Oliveira
- Department of Biology, New York University, New York, NY 10003, USA
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47
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Affiliation(s)
- J Chiu
- Cardiac Non-Invasive Laboratory, Department of Medicine, Division of Cardiology, Cedars-Sinai Medical Center, Los Angeles, California 90048, USA
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Malek RL, Toman RE, Edsall LC, Wong S, Chiu J, Letterle CA, Van Brocklyn JR, Milstien S, Spiegel S, Lee NH. Nrg-1 belongs to the endothelial differentiation gene family of G protein-coupled sphingosine-1-phosphate receptors. J Biol Chem 2001; 276:5692-9. [PMID: 11069896 DOI: 10.1074/jbc.m003964200] [Citation(s) in RCA: 87] [Impact Index Per Article: 3.8] [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: 11/06/2022] Open
Abstract
The previously cloned rat nerve growth factor-regulated G protein-coupled receptor NRG-1 (Glickman, M., Malek, R. L., Kwitek-Black, A. E., Jacob, H. J., and Lee N. H. (1999) Mol. Cell. Neurosci. 14, 141-52), also known as EDG-8, binds sphingosine-1-phosphate (S1P) with high affinity and specificity. In this paper we examined the signal transduction pathways regulated by the binding of S1P to EDG-8. In Chinese hamster ovary cells heterologously expressing EDG-8, S1P inhibited forskolin-induced cAMP accumulation and activated c-Jun NH2-terminal kinase. Surprisingly, S1P inhibited serum-induced activation of extracellular regulated protein kinase 1 and 2 (ERK1/2). Treatment with pertussis toxin, which ADP-ribosylates and inactivates G(i), blocked S1P-mediated inhibition of cAMP accumulation, but had no effect on c-Jun NH2-terminal kinase activation or inhibition of ERK1/2. The inhibitory effect of S1P on ERK1/2 activity was abolished by treatment with orthovanadate, suggesting the involvement of a tyrosine phosphatase. A subunit selective [35S] guanosine 5'-3-O-(thio)triphosphate binding assay demonstrates that EDG-8 activated G(i/o) and G12 but not Gs and G(q/11) in response to S1P. In agreement, EDG-8 did not stimulate phosphoinositide turnover or cAMP accumulation. The ability of S1P to induce mitogenesis in cells expressing the EDG-1 subfamily of G protein-coupled receptors is well characterized. In contrast, S1P inhibited proliferation in Chinese hamster ovary cells expressing EDG-8 but not empty vector. The antiproliferative effect, like S1P-mediated ERK1/2 inhibition, was orthovanadate-sensitive and pertussis toxin-insensitive. Our results indicate that EDG-8, a member of the EDG-1 subfamily, couples to unique signaling pathways.
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Affiliation(s)
- R L Malek
- Department of Molecular and Cellular Biology, Institute for Genomic Research, Rockville, Maryland 20850, USA
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Sims C, Chiu J, Harvey RD. Tyrosine phosphatase inhibitors selectively antagonize beta-adrenergic receptor-dependent regulation of cardiac ion channels. Mol Pharmacol 2000; 58:1213-21. [PMID: 11093756 DOI: 10.1124/mol.58.6.1213] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
beta-Adrenergic receptor stimulation regulates the activity of several different cardiac ion channels through an adenylate cyclase/cAMP/protein kinase A-dependent mechanism. Previous work has suggested that basal tyrosine kinase activity attenuates the beta-adrenergic responsiveness of these cardiac ion channels, supporting the idea that tyrosine phosphorylation exerts an inhibitory effect at some point in the common signaling pathway. To determine which element in the beta-adrenergic pathway is regulated by tyrosine kinase activity, we studied the effects of various protein tyrosine phosphatase (PTP) inhibitors on the cAMP-dependent regulation of the L-type Ca(2+) current in guinea pig ventricular myocytes. Three such compounds, sodium orthovanadate, peroxovanadate, and bpV(phen), had no effect on the basal Ca(2+) current, yet each caused a pronounced inhibition of the Ca(2+) current stimulated by the beta-adrenergic receptor agonist isoproterenol. These observations are consistent with the idea that basal tyrosine kinase activity is capable of inhibiting beta-adrenergic responses. However, these PTP inhibitors had no effect on cAMP-dependent stimulation of the Ca(2+) current via activation of adenylate cyclase with forskolin or activation of H(2)-histaminergic receptors with histamine. These results are consistent with the idea that inhibition of PTP activity produces an inhibitory effect involving a tyrosine kinase-dependent mechanism acting selectively at the level of the beta-adrenergic receptor. This signaling mechanism does not seem to be linked to tyrosine kinase activity associated with insulin and insulin-like growth factor receptors, because acute exposure to agonists of these receptors did not inhibit isoproterenol regulation of the Ca(2+) current.
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Affiliation(s)
- C Sims
- Department of Physiology and Biophysics, Case Western Reserve University, Cleveland, Ohio 44106-4970, USA
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Stochaj U, Rassadi R, Chiu J. Stress-mediated inhibition of the classical nuclear protein import pathway and nuclear accumulation of the small GTPase Gsp1p. FASEB J 2000; 14:2130-2. [PMID: 11024003 DOI: 10.1096/fj.99-0751fje] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Stress modifies all aspects of cellular physiology, including the targeting of macromolecules to the nucleus. To determine how distinct types of stress affect classical nuclear protein import, we followed the distribution of NLS-GFP, a reporter protein containing a classical nuclear localization sequence (NLS) fused to green fluorescent protein GFP. Nuclear accumulation of NLS-GFP requires import to be constitutively active; inhibition of import redistributes NLS-GFP throughout the nucleus and cytoplasm. In the yeast Saccharomyces cerevisiae, starvation, heat shock, ethanol and hydrogen peroxide rapidly inhibited classical nuclear import, whereas osmotic stress had no effect. To define the mechanisms underlying the inhibition of classical nuclear import, we located soluble components of the nuclear transport apparatus. Failure to accumulate NLS-GFP in the nucleus always correlated with a redistribution of the small GTPase Gsp1p. Whereas predominantly nuclear under normal conditions, Gsp1p equilibrated between nucleus and cytoplasm in cells exposed to starvation, heat, ethanol or hydrogen peroxide. Furthermore, analysis of yeast strains carrying mutations in different nuclear transport factors demonstrated a role for NTF2, PRP20 and MOG1 in establishing a Gsp1p gradient, as conditional lethal alleles of NTF2 and PRP20 or a deletion of MOG1 prevented Gsp1p nuclear accumulation. On the basis of these results, we now propose that certain types of stress release Gsp1p from its nuclear anchors, thereby promoting a collapse of the nucleocytoplasmic Gsp1p gradient and inhibiting classical nuclear protein import.
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Affiliation(s)
- U Stochaj
- Department of Physiology, McGill University, Montreal, PQ, Canada, H3G 1Y6.
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