1
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Gotchev D, Dorsey BD, Nguyen D, Kakarla R, Dugan B, Chen S, Gao M, Bailey L, Liu F, Harasym T, Chiu T, Tang S, Lee ACH, Cole AG, Sofia MJ. Structure-Activity Relationships and Discovery of ( S)-6-Isopropyl-2-methoxy-3-(3-methoxypropoxy)-10-oxo-5,10-dihydro-6 H-pyrido[1,2- h][1,7]naphthyridine-9-carboxylic Acid (AB-452), a Novel Orally Available HBV RNA Destabilizer. J Med Chem 2024; 67:1421-1446. [PMID: 38190324 DOI: 10.1021/acs.jmedchem.3c01981] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2024]
Abstract
Approved therapies for hepatitis B virus (HBV) treatment include nucleos(t)ides and interferon alpha (IFN-α) which effectively suppress viral replication, but they rarely lead to cure. Expression of viral proteins, especially surface antigen of the hepatitis B virus (HBsAg) from covalently closed circular DNA (cccDNA) and the integrated genome, is believed to contribute to the persistence of HBV. This work focuses on therapies that target the expression of HBV proteins, in particular HBsAg, which differs from current treatments. Here we describe the identification of AB-452, a dihydroquinolizinone (DHQ) analogue. AB-452 is a potent HBV RNA destabilizer by inhibiting PAPD5/7 proteins in vitro with good in vivo efficacy in a chronic HBV mouse model. AB-452 showed acceptable tolerability in 28-day rat and dog toxicity studies, and a high degree of oral exposure in multiple species. Based on its in vitro and in vivo profiles, AB-452 was identified as a clinical development candidate.
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Affiliation(s)
- Dimitar Gotchev
- Arbutus Biopharma, 701 Veterans Circle, Warminster, Pennsylvania 18974, United States
| | - Bruce D Dorsey
- Arbutus Biopharma, 701 Veterans Circle, Warminster, Pennsylvania 18974, United States
| | - Duyan Nguyen
- Arbutus Biopharma, 701 Veterans Circle, Warminster, Pennsylvania 18974, United States
| | - Ramesh Kakarla
- Arbutus Biopharma, 701 Veterans Circle, Warminster, Pennsylvania 18974, United States
| | - Benjamin Dugan
- Arbutus Biopharma, 701 Veterans Circle, Warminster, Pennsylvania 18974, United States
| | - Shuai Chen
- Arbutus Biopharma, 701 Veterans Circle, Warminster, Pennsylvania 18974, United States
| | - Min Gao
- Arbutus Biopharma, 701 Veterans Circle, Warminster, Pennsylvania 18974, United States
| | - Laurèn Bailey
- Arbutus Biopharma, 701 Veterans Circle, Warminster, Pennsylvania 18974, United States
| | - Fei Liu
- Arbutus Biopharma, 701 Veterans Circle, Warminster, Pennsylvania 18974, United States
| | - Troy Harasym
- Arbutus Biopharma, 701 Veterans Circle, Warminster, Pennsylvania 18974, United States
| | - Tim Chiu
- Arbutus Biopharma, 701 Veterans Circle, Warminster, Pennsylvania 18974, United States
| | - Sunny Tang
- Arbutus Biopharma, 701 Veterans Circle, Warminster, Pennsylvania 18974, United States
| | - Amy C-H Lee
- Arbutus Biopharma, 701 Veterans Circle, Warminster, Pennsylvania 18974, United States
| | - Andrew G Cole
- Arbutus Biopharma, 701 Veterans Circle, Warminster, Pennsylvania 18974, United States
| | - Michael J Sofia
- Arbutus Biopharma, 701 Veterans Circle, Warminster, Pennsylvania 18974, United States
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Cole AG, Kultgen SG, Mani N, Quintero JG, Yi Fan K, Ardzinski A, Stever K, Dorsey BD, Phelps JR, Lee ACH, Thi EP, Chiu T, Tang S, Horanyi PS, Mayclin SJ, Harasym TO, Sofia MJ. Design, synthesis, and structure-activity relationship of a bicyclic HBV capsid assembly modulator chemotype leading to the identification of clinical candidate AB-506. Bioorg Med Chem Lett 2023; 94:129456. [PMID: 37633618 DOI: 10.1016/j.bmcl.2023.129456] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2023] [Revised: 08/15/2023] [Accepted: 08/22/2023] [Indexed: 08/28/2023]
Abstract
Disruption of the HBV capsid assembly process through small-molecule interaction with HBV core protein is a validated target for the suppression of hepatitis B viral replication and the development of new antivirals. Through combination of key structural features associated with two distinct series of capsid assembly modulators, a novel aminochroman-based chemotype was identified. Optimization of anti-HBV potency through generation of SAR in addition to further core modifications provided a series of related functionalized aminoindanes. Key compounds demonstrated excellent cellular potency in addition to favorable ADME and pharmacokinetic profiles and were shown to be highly efficacious in a mouse model of HBV replication. Aminoindane derivative AB-506 was subsequently advanced into clinical development.
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Affiliation(s)
- Andrew G Cole
- Arbutus Biopharma, Inc., 701 Veterans Circle, Warminster, PA 18974, USA.
| | - Steven G Kultgen
- Arbutus Biopharma, Inc., 701 Veterans Circle, Warminster, PA 18974, USA
| | - Nagraj Mani
- Arbutus Biopharma, Inc., 701 Veterans Circle, Warminster, PA 18974, USA
| | - Jorge G Quintero
- Arbutus Biopharma, Inc., 701 Veterans Circle, Warminster, PA 18974, USA
| | - Kristi Yi Fan
- Arbutus Biopharma, Inc., 701 Veterans Circle, Warminster, PA 18974, USA
| | - Andrzej Ardzinski
- Arbutus Biopharma, Inc., 701 Veterans Circle, Warminster, PA 18974, USA
| | - Kim Stever
- Arbutus Biopharma, Inc., 701 Veterans Circle, Warminster, PA 18974, USA
| | - Bruce D Dorsey
- Arbutus Biopharma, Inc., 701 Veterans Circle, Warminster, PA 18974, USA
| | - Janet R Phelps
- Arbutus Biopharma, Inc., 701 Veterans Circle, Warminster, PA 18974, USA
| | - Amy C H Lee
- Arbutus Biopharma, Inc., 701 Veterans Circle, Warminster, PA 18974, USA
| | - Emily P Thi
- Arbutus Biopharma, Inc., 701 Veterans Circle, Warminster, PA 18974, USA
| | - Tim Chiu
- Arbutus Biopharma, Inc., 701 Veterans Circle, Warminster, PA 18974, USA
| | - Sunny Tang
- Arbutus Biopharma, Inc., 701 Veterans Circle, Warminster, PA 18974, USA
| | - Peter S Horanyi
- UCB Pharma, 87 Cambridge Park Drive, Cambridge, MA 02140, USA
| | | | - Troy O Harasym
- Arbutus Biopharma, Inc., 701 Veterans Circle, Warminster, PA 18974, USA
| | - Michael J Sofia
- Arbutus Biopharma, Inc., 701 Veterans Circle, Warminster, PA 18974, USA
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3
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Cole AG, Kultgen SG, Mani N, Ardzinski A, Fan KY, Thi EP, Dorsey BD, Stever K, Chiu T, Tang S, Daly O, Phelps JR, Harasym T, Olland A, Suto RK, Sofia MJ. The identification of highly efficacious functionalised tetrahydrocyclopenta[ c]pyrroles as inhibitors of HBV viral replication through modulation of HBV capsid assembly. RSC Med Chem 2022; 13:343-349. [PMID: 35434625 PMCID: PMC8942244 DOI: 10.1039/d1md00318f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Accepted: 01/17/2022] [Indexed: 01/21/2023] Open
Abstract
Disruption of the HBV viral life cycle with small molecules that prevent the encapsidation of pregenomic RNA and viral polymerase through binding to HBV core protein is a clinically validated approach to inhibiting HBV viral replication. Herein we report the further optimisation of clinical candidate AB-506 through core modification with a focus on increasing oral exposure and oral half-life. Maintenance of high levels of anti-HBV cellular potency in conjunction with improvements in pharmacokinetic properties led to multi-log10 reductions in serum HBV DNA following low, once-daily oral dosing for key analogues in a preclinical animal model of HBV replication.
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Affiliation(s)
- Andrew G. Cole
- Arbutus Biopharma, Inc.701 Veterans CircleWarminsterPA 18974USA
| | | | - Nagraj Mani
- Arbutus Biopharma, Inc.701 Veterans CircleWarminsterPA 18974USA
| | | | - Kristi Yi Fan
- Arbutus Biopharma, Inc.701 Veterans CircleWarminsterPA 18974USA
| | - Emily P. Thi
- Arbutus Biopharma, Inc.701 Veterans CircleWarminsterPA 18974USA
| | - Bruce D. Dorsey
- Arbutus Biopharma, Inc.701 Veterans CircleWarminsterPA 18974USA
| | - Kim Stever
- Arbutus Biopharma, Inc.701 Veterans CircleWarminsterPA 18974USA
| | - Tim Chiu
- Arbutus Biopharma, Inc.701 Veterans CircleWarminsterPA 18974USA
| | - Sunny Tang
- Arbutus Biopharma, Inc.701 Veterans CircleWarminsterPA 18974USA
| | - Owen Daly
- Arbutus Biopharma, Inc.701 Veterans CircleWarminsterPA 18974USA
| | - Janet R. Phelps
- Arbutus Biopharma, Inc.701 Veterans CircleWarminsterPA 18974USA
| | - Troy Harasym
- Arbutus Biopharma, Inc.701 Veterans CircleWarminsterPA 18974USA
| | - Andrea Olland
- Xtal BioStructures Inc.12 Michigan DriveNatickMA 01760USA
| | - Robert K. Suto
- Xtal BioStructures Inc.12 Michigan DriveNatickMA 01760USA
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4
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Mani N, Cole AG, Phelps JR, Ardzinski A, Burns R, Chiu T, Cuconati A, Dorsey BD, Evangelista E, Fan K, Guo F, Harasym TO, Kadhim S, Kowalski R, Kultgen SG, Lee ACH, Li AH, Majeski SA, Miller A, Pasetka C, Reid SP, Rijnbrand R, Micolochick Steuer HM, Stever K, Tang S, Teng X, Wang X, Sofia MJ. Preclinical characterization of AB-506, an inhibitor of HBV replication targeting the viral core protein. Antiviral Res 2021; 197:105211. [PMID: 34826506 DOI: 10.1016/j.antiviral.2021.105211] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [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: 08/28/2021] [Revised: 11/19/2021] [Accepted: 11/22/2021] [Indexed: 02/06/2023]
Abstract
AB-506, a small-molecule inhibitor targeting the HBV core protein, inhibits viral replication in vitro (HepAD38 cells: EC50 of 0.077 μM, CC50 > 25 μM) and in vivo (HBV mouse model: ∼3.0 log10 reductions in serum HBV DNA compared to the vehicle control). Binding of AB-506 to HBV core protein accelerates capsid assembly and inhibits HBV pgRNA encapsidation. Furthermore, AB-506 blocks cccDNA establishment in HBV-infected HepG2-hNTCP-C4 cells and primary human hepatocytes, leading to inhibition of viral RNA, HBsAg, and HBeAg production (EC50 from 0.64 μM to 1.92 μM). AB-506 demonstrated activity across HBV genotypes A-H and maintains antiviral activity against nucleos(t)ide analog-resistant variants in vitro. Evaluation of AB-506 against a panel of core variants showed that T33N/Q substitutions results in >200-fold increase in EC50 values, while L30F, L37Q, and I105T substitutions showed an 8 to 20-fold increase in EC50 values in comparison to the wild-type. In vitro combinations of AB-506 with NAs or an RNAi agent were additive to moderately synergistic. AB-506 exhibits good oral bioavailability, systemic exposure, and higher liver to plasma ratios in rodents, a pharmacokinetic profile supporting clinical development for chronic hepatitis B.
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Affiliation(s)
- Nagraj Mani
- Arbutus Biopharma Inc., 701 Veterans Circle, Warminster, PA, 18974, USA.
| | - Andrew G Cole
- Arbutus Biopharma Inc., 701 Veterans Circle, Warminster, PA, 18974, USA
| | - Janet R Phelps
- Arbutus Biopharma Inc., 701 Veterans Circle, Warminster, PA, 18974, USA
| | - Andrzej Ardzinski
- Arbutus Biopharma Inc., 701 Veterans Circle, Warminster, PA, 18974, USA
| | - Robbin Burns
- Arbutus Biopharma Inc., 701 Veterans Circle, Warminster, PA, 18974, USA
| | - Tim Chiu
- Arbutus Biopharma Inc., 701 Veterans Circle, Warminster, PA, 18974, USA
| | - Andrea Cuconati
- Arbutus Biopharma Inc., 701 Veterans Circle, Warminster, PA, 18974, USA
| | - Bruce D Dorsey
- Arbutus Biopharma Inc., 701 Veterans Circle, Warminster, PA, 18974, USA
| | - Ellen Evangelista
- Arbutus Biopharma Inc., 701 Veterans Circle, Warminster, PA, 18974, USA
| | - Kristi Fan
- Arbutus Biopharma Inc., 701 Veterans Circle, Warminster, PA, 18974, USA
| | - Fang Guo
- Arbutus Biopharma Inc., 701 Veterans Circle, Warminster, PA, 18974, USA
| | - Troy O Harasym
- Arbutus Biopharma Inc., 701 Veterans Circle, Warminster, PA, 18974, USA
| | - Salam Kadhim
- Arbutus Biopharma Inc., 701 Veterans Circle, Warminster, PA, 18974, USA
| | - Roseann Kowalski
- Arbutus Biopharma Inc., 701 Veterans Circle, Warminster, PA, 18974, USA
| | - Steven G Kultgen
- Arbutus Biopharma Inc., 701 Veterans Circle, Warminster, PA, 18974, USA
| | - Amy C H Lee
- Arbutus Biopharma Inc., 701 Veterans Circle, Warminster, PA, 18974, USA
| | - Alice H Li
- Arbutus Biopharma Inc., 701 Veterans Circle, Warminster, PA, 18974, USA
| | - Sara A Majeski
- Arbutus Biopharma Inc., 701 Veterans Circle, Warminster, PA, 18974, USA
| | - Angela Miller
- Arbutus Biopharma Inc., 701 Veterans Circle, Warminster, PA, 18974, USA
| | - Chris Pasetka
- Arbutus Biopharma Inc., 701 Veterans Circle, Warminster, PA, 18974, USA
| | - Stephen P Reid
- Arbutus Biopharma Inc., 701 Veterans Circle, Warminster, PA, 18974, USA
| | - Rene Rijnbrand
- Arbutus Biopharma Inc., 701 Veterans Circle, Warminster, PA, 18974, USA
| | | | - Kim Stever
- Arbutus Biopharma Inc., 701 Veterans Circle, Warminster, PA, 18974, USA
| | - Sunny Tang
- Arbutus Biopharma Inc., 701 Veterans Circle, Warminster, PA, 18974, USA
| | - Xiaowei Teng
- Arbutus Biopharma Inc., 701 Veterans Circle, Warminster, PA, 18974, USA
| | - Xiaohe Wang
- Arbutus Biopharma Inc., 701 Veterans Circle, Warminster, PA, 18974, USA
| | - Michael J Sofia
- Arbutus Biopharma Inc., 701 Veterans Circle, Warminster, PA, 18974, USA
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Hu B, Hsiao-Wei Y, Chiu T, Li-Ling L, Chen Y. THE VALIDITY OF THE STUDY OF OSTEOPOROTIC FRACTURES (SOF) INDEX FOR ASSESSING COMMUNITY-BASED OLDER ADULTS IN TAIWAN. Innov Aging 2018. [PMCID: PMC6239382 DOI: 10.1093/geroni/igy031.3746] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Taiwan’s Ten-Year Long-Term Care Project (TLTCP) version 2.0 has expanded to include frail adults in late 2017; however, tools for measuring frailty remain controversial. On the one hand, it has become common to use Fried’s Frailty Phenotype index to measure older adults’ frailty in Taiwan and advanced countries. On the other hand, the Taiwanese government uses the Study of Osteoporotic Fractures index (SOF index) to assess the degree of frailty and whether to receive publicly-funded exercise programs. This study aimed at assessing properties of tools of the SOF index and Fried’s Frailty Phenotype index among general, community-dwelling older adults in Taiwan. In this cross-sectional survey study, purposive sampling was employed to collect data, with 471 older adults. The participants were older than 65 years and lived in Taipei City. To analyze the data, Spearman’s Rank Correlation Coefficient was employed to understand the association between frailty as measured by the two indexes and area under the curve (AUC) statistics was used to test the respective models by measuring the predictive validity from the two indexes. Study findings showed a moderate association between Fried’s Frailty Phenotype index and the SOF index (p<0.001). However, these two frailty indexes were inconsistent in their ability to predict validity. The result of AUC showed that while the SOF predicted falls better (p <0.001), Fried’s Frailty Phenotype index predicted disability better (p <0.001). Similar to the results from advanced countries, SOF index is a valid tool to evaluate frailty, especially for general, community-dwelling older adults in Taiwan.
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Affiliation(s)
- B Hu
- National Taiwan University
| | - Y Hsiao-Wei
- Department of Gerontology and Health Care Management, Chang Gung University of Science and Technology, Taoyuan, Taiwan
| | - T Chiu
- Graduate Institute of Long-term Care, Tzu Chi University of Science and Technology, Hualien City, Taiwan
| | - L Li-Ling
- . Nangang District Health Center, Taipei City, Taiwan, R.O.C
| | - Y Chen
- Institute of Health Policy and Management, College of Public Health, National Taiwan University, Taipei, Taiwan
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6
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Zhou T, Block T, Liu F, Kondratowicz AS, Sun L, Rawat S, Branson J, Guo F, Steuer HM, Liang H, Bailey L, Moore C, Wang X, Cuconatti A, Gao M, Lee ACH, Harasym T, Chiu T, Gotchev D, Dorsey B, Rijnbrand R, Sofia MJ. HBsAg mRNA degradation induced by a dihydroquinolizinone compound depends on the HBV posttranscriptional regulatory element. Antiviral Res 2017; 149:191-201. [PMID: 29133129 DOI: 10.1016/j.antiviral.2017.11.009] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2017] [Revised: 11/01/2017] [Accepted: 11/07/2017] [Indexed: 12/23/2022]
Abstract
In pursuit of novel therapeutics targeting the hepatitis B virus (HBV) infection, we evaluated a dihydroquinolizinone compound (DHQ-1) that in the nanomolar range reduced the production of virion and surface protein (HBsAg) in tissue culture. This compound also showed broad HBV genotype coverage, but was inactive against a panel of DNA and RNA viruses of other species. Oral administration of DHQ-1 in the AAV-HBV mouse model resulted in a significant reduction of serum HBsAg as soon as 4 days following the commencement of treatment. Reduction of HBV markers in both in vitro and in vivo experiments was related to the reduced amount of viral RNA including pre-genomic RNA (pgRNA) and 2.4/2.1 kb HBsAg mRNA. Nuclear run-on and subcellular fractionation experiments indicated that DHQ-1 mediated HBV RNA reduction was the result of accelerated viral RNA degradation in the nucleus, rather than the consequence of inhibition of transcription initiation. Through mutagenesis of HBsAg gene sequences, we found induction of HBsAg mRNA decay by DHQ-1 required the presence of the HBV posttranscriptional regulatory element (HPRE), with a 109 nucleotides sequence within the central region of the HPRE alpha sub-element being the most critical. Taken together, the current study shows that a small molecule can reduce the overall levels of HBV RNA, especially the HBsAg mRNA, and viral surface proteins. This may shed light on the development of a new class of HBV therapeutics.
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Affiliation(s)
- Tianlun Zhou
- Baruch S. Blumberg Institute, Department of Translational Medicine, Doylestown, PA 18902, United States.
| | - Timothy Block
- Baruch S. Blumberg Institute, Department of Translational Medicine, Doylestown, PA 18902, United States
| | - Fei Liu
- Arbutus BioPharma, 701 Veterans Circle, Warminster, PA 18974, United States
| | - Andrew S Kondratowicz
- Arbutus BioPharma, 100 - 8900 Glenlyon Parkway, Burnaby, British Columbia V5J 5J8, Canada
| | - Liren Sun
- Baruch S. Blumberg Institute, Department of Translational Medicine, Doylestown, PA 18902, United States
| | - Siddhartha Rawat
- Baruch S. Blumberg Institute, Department of Translational Medicine, Doylestown, PA 18902, United States
| | - Jeffrey Branson
- Baruch S. Blumberg Institute, Department of Translational Medicine, Doylestown, PA 18902, United States
| | - Fang Guo
- Arbutus BioPharma, 701 Veterans Circle, Warminster, PA 18974, United States
| | | | - Hongyan Liang
- Baruch S. Blumberg Institute, Department of Translational Medicine, Doylestown, PA 18902, United States
| | - Lauren Bailey
- Arbutus BioPharma, 701 Veterans Circle, Warminster, PA 18974, United States
| | - Chris Moore
- Arbutus BioPharma, 701 Veterans Circle, Warminster, PA 18974, United States
| | - Xiaohe Wang
- Arbutus BioPharma, 701 Veterans Circle, Warminster, PA 18974, United States
| | - Andy Cuconatti
- Arbutus BioPharma, 701 Veterans Circle, Warminster, PA 18974, United States
| | - Min Gao
- Arbutus BioPharma, 701 Veterans Circle, Warminster, PA 18974, United States
| | - Amy C H Lee
- Arbutus BioPharma, 100 - 8900 Glenlyon Parkway, Burnaby, British Columbia V5J 5J8, Canada
| | - Troy Harasym
- Arbutus BioPharma, 100 - 8900 Glenlyon Parkway, Burnaby, British Columbia V5J 5J8, Canada
| | - Tim Chiu
- Arbutus BioPharma, 100 - 8900 Glenlyon Parkway, Burnaby, British Columbia V5J 5J8, Canada
| | - Dimitar Gotchev
- Arbutus BioPharma, 701 Veterans Circle, Warminster, PA 18974, United States
| | - Bruce Dorsey
- Arbutus BioPharma, 701 Veterans Circle, Warminster, PA 18974, United States
| | - Rene Rijnbrand
- Arbutus BioPharma, 701 Veterans Circle, Warminster, PA 18974, United States
| | - Michael J Sofia
- Arbutus BioPharma, 701 Veterans Circle, Warminster, PA 18974, United States.
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Chiu T, Yu H, Lai W, Li H, Tsai E, Chen Y. MOVING FROM FRAGMENTED TOWARD AN INTEGRATED SYSTEM: A NEW LONG-TERM CARE POLICY IN FAST-AGING COUNTRY. Innov Aging 2017. [DOI: 10.1093/geroni/igx004.1600] [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: 11/13/2022] Open
Affiliation(s)
- T. Chiu
- Institute of Health Policy and Management, National Taiwan University, Taipei, Taiwan,
| | - H. Yu
- Institute of Health Policy and Management, National Taiwan University, Taipei, Taiwan,
| | - W. Lai
- Central Taiwan Joint Services Center, Executive Yuan, Taichung, Taiwan,
| | - H. Li
- Quixotic Implement Foundation, Nantou, Taiwan,
| | - E. Tsai
- Shuan Lien Social Welfare Foundation, Taipei, Taiwan
| | - Y. Chen
- Institute of Health Policy and Management, National Taiwan University, Taipei, Taiwan,
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Rozario T, Chiu T, Lu W, Chen M, Yan Y, Bereg S, Mao W. TH-AB-202-01: Daily Lung Tumor Motion Characterization On EPIDs Using a Markerless Tiling Model. Med Phys 2016. [DOI: 10.1118/1.4958065] [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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9
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Chiu T, Yang B, Law M, Lam W, Kong C, Geng H, Cheung K, Yu S. SU-F-T-548: An Extraction Method for Correction of Detector Volume Effect in Small Field Profile Measurement. Med Phys 2016. [DOI: 10.1118/1.4956733] [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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10
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Chiu T, Long T, Modiri A, Tian Z, Sawant A, Yan Y, Jiang S, Gu X. TH-EF-BRB-04: 4π Dynamic Conformal Arc Therapy Dynamic Conformal Arc Therapy (DCAT) for SBRT. Med Phys 2016. [DOI: 10.1118/1.4958250] [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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11
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Zhao B, Chiu T, Gu X, Lee H, Nedzi L, Jiang S. TU-H-CAMPUS-TeP1-05: Fast Processed 3D Printing-Aided Urethane Resin (PUR) Bolus in Radiation Therapy. Med Phys 2016. [DOI: 10.1118/1.4957678] [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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12
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Chiu T, Zhang Y, Hrycushko B, Zhao B, Chopra R, Jiang S, Gu X. WE-DE-BRA-02: BEST IN PHYSICS (JOINT IMAGING-THERAPY): Prototype for An In-Room Supercompounded 3D Volumetric Ultrasound Image Guidance System for Prone Breast SBRT. Med Phys 2016. [DOI: 10.1118/1.4957831] [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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13
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Urban MK, Chiu T, Wolfe S, Magid S. Electronic Ordering System Improves Postoperative Pain Management After Total Knee or Hip Arthroplasty. Appl Clin Inform 2015; 6:591-9. [PMID: 26448800 DOI: 10.4338/aci-2014-12-ra-0114] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [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: 12/11/2014] [Accepted: 05/09/2015] [Indexed: 12/28/2022] Open
Abstract
OBJECTIVES The authors investigated the impact of computerized provider order entry (CPOE) on the delivery times of analgesia and subsequent patient outcomes. We hypothesized that patients would report less pain and use less pain medications compared with the previous paper-based system. METHODS Two groups of patients after a total hip (THA) or knee arthroplasty (TKA) were retrospectively compared: one comprising 106 patients when the paper-based ordering system was in effect (conventional group), and one comprising 96 patients after CPOE was installed (electronic group). All patients received a regional anaesthetic at surgery (combined spinal-epidural). TKA patients also received a single-injection femoral nerve block. After transfer to the postoperative anaesthesia care unit (PACU), a patient-controlled epidural analgesia (PCEA) infusion was initiated. The following data was collected from the PACU record: time to initiation of analgesia, visual analog scale (VAS) pain scores at initiation of analgesia and hourly for the first postoperative day (POD), volume of pain medication used, length of stay (LOS) in the PACU and the hospital. RESULTS The time to initiation of analgesia from arrival in the PACU was significantly lower in the electronic group compared to the conventional group (24.5 ± 28.3 minutes vs. 51.1 ± 26.2 minutes; mean ± SD, p < 0.001), as were VAS pain scores (0.82 ± 1.08 vs. 1.5 ± 1.52, p < 0.001) and the volume of PCEA needed to control pain (27.9 ± 20.2 ml vs. 34.8 ± 20.3 ml, p = 0.001) at 4 hours postoperatively. PACU LOS and hospital LOS did not significantly differ in the two groups. CONCLUSIONS After implementation of CPOE, patients received their postoperative analgesia faster, had less pain, and required less medication.
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Affiliation(s)
- M K Urban
- Hospital for Special Surgery, Anesthesiology , New York, NY, United States
| | - T Chiu
- Hospital for Special Surgery, Quality Research Center , Auckland, New Zealand
| | - S Wolfe
- Hospital for Special Surgery, Quality Research Center , New York, NY, United States
| | - S Magid
- Hospital for Special Surgery, Quality Research Center , New York, NY, United States
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14
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Chiu T, Yan Y, Ramirez E, Lee P, Jiang S, Gu X. SU-E-T-217: Comprehensive Dosimetric Evaluation On 3D-CRT, IMRT and Non-Coplanar Arc Treatment for Prone Accelerated Partial Breast Irradiation (APBI). Med Phys 2015. [DOI: 10.1118/1.4924578] [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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15
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Chiu T, Hrycushko B, Zhao B, Jiang S, Gu X. MO-DE-210-06: Development of a Supercompounded 3D Volumetric Ultrasound Image Guidance System for Prone Accelerated Partial Breast Irradiation (APBI). Med Phys 2015. [DOI: 10.1118/1.4925368] [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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16
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Lam W, Geng H, Kong C, Yang B, Chiu T, Cheung K, Yu S. Dosimetric Impact of Dose Servo Control on Long Helical Tomotherapy Treatment Delivery. Int J Radiat Oncol Biol Phys 2014. [DOI: 10.1016/j.ijrobp.2014.05.2137] [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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17
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Cai Y, Zhong Z, Guo X, Gu X, Chiu T, Kearney V, Liu H, Jiang L, Chen S, Yordy J, Nedzi L, Mao W. TU-A-9A-01: A Precise Deformable Image Registration System Using Feature-Based Irregular Meshes. Med Phys 2014. [DOI: 10.1118/1.4889236] [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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18
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Rozario T, Bereg S, Chiu T, Liu H, Kearney V, Jiang L, Mao W. SU-E-J-23: An Accurate Algorithm to Match Imperfectly Matched Images for Lung Tumor Detection Without Markers. Med Phys 2014. [DOI: 10.1118/1.4888074] [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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19
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Chiu T, Rozario T, Bereg S, Klash S, Kearney V, Liu H, Jiang L, Foster R, Mao W. TH-E-17A-10: Markerless Lung Tumor Tracking Based On Beams Eye View EPID Images. Med Phys 2014. [DOI: 10.1118/1.4889685] [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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20
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Chiu T, Foster R, Mao W. SU-E-J-272: Long-Term Evaluation and Cross-Checking of Two Geometric Calibration Systems On Linacs. Med Phys 2014. [DOI: 10.1118/1.4888326] [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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21
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Kearney V, Gu X, Chen S, Jiang L, Liu H, Chiu T, Yordy J, Nedzi L, Mao W. WE-D-9A-02: Automated Landmark-Guided CT to Cone-Beam CT Deformable Image Registration. Med Phys 2014. [DOI: 10.1118/1.4889418] [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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22
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Zhong Z, Cai Y, Guo X, Jia X, Chiu T, Kearney V, Liu H, Jiang L, Chen S, Yordy J, Nedzi L, Mao W. WE-D-9A-01: A Novel Mesh-Based Deformable Surface-Contour Registration. Med Phys 2014. [DOI: 10.1118/1.4889417] [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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23
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Tunduguru R, Chiu T, Klip A, Thurmond D. Insulin‐stimulated PAK1 activation is required for glucose uptake in skeletal muscle cells (797.1). FASEB J 2014. [DOI: 10.1096/fasebj.28.1_supplement.797.1] [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: 11/11/2022]
Affiliation(s)
| | - Tim Chiu
- Biochemistry University of TORONTOTorontoONCanada
| | - Amira Klip
- Biochemistry University of TORONTOTorontoONCanada
| | - Debbie Thurmond
- Pediatrics Indiana University School of MedicineIndianapolisINUnited States
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24
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Yang B, Leung K, Cheung K, Yu S, Geng H, Lam W, Lo S, Chiu T. A Comparison of the Dosimetric Properties of a Plastic Scintillator-CCD and a Fluorescent Screen-CCD System in QA of Radiation Therapy Beams. Int J Radiat Oncol Biol Phys 2013. [DOI: 10.1016/j.ijrobp.2013.06.1535] [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: 10/26/2022]
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25
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Lam W, Geng H, Kong C, Cheung K, Yu S, Chiu T. Quality Assurance of Helical Tomotherapy Stereotactic Radiosurgery Treatment Using 4D Detector Array. Int J Radiat Oncol Biol Phys 2013. [DOI: 10.1016/j.ijrobp.2013.06.1532] [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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26
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Chiu T, Chen L, Su D, Lo H, Chen C, Wang S, Chen W. 57 Rhodiola Crenulata Extract Prophylaxis for Acute Mountain Sickness: A Randomized, Double Blind, Placebo Controlled, Crossover Trial. Ann Emerg Med 2012. [DOI: 10.1016/j.annemergmed.2012.06.336] [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: 10/27/2022]
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27
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Boguslavsky S, Chiu T, Foley KP, Osorio-Fuentealba C, Antonescu CN, Bayer KU, Bilan PJ, Klip A. Myo1c binding to submembrane actin mediates insulin-induced tethering of GLUT4 vesicles. Mol Biol Cell 2012; 23:4065-78. [PMID: 22918957 PMCID: PMC3469521 DOI: 10.1091/mbc.e12-04-0263] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
GLUT4-containing vesicles cycle between the plasma membrane and intracellular compartments. Insulin promotes GLUT4 exocytosis by regulating GLUT4 vesicle arrival at the cell periphery and its subsequent tethering, docking, and fusion with the plasma membrane. The molecular machinery involved in GLUT4 vesicle tethering is unknown. We show here that Myo1c, an actin-based motor protein that associates with membranes and actin filaments, is required for insulin-induced vesicle tethering in muscle cells. Myo1c was found to associate with both mobile and tethered GLUT4 vesicles and to be required for vesicle capture in the total internal reflection fluorescence (TIRF) zone beneath the plasma membrane. Myo1c knockdown or overexpression of an actin binding-deficient Myo1c mutant abolished insulin-induced vesicle immobilization, increased GLUT4 vesicle velocity in the TIRF zone, and prevented their externalization. Conversely, Myo1c overexpression immobilized GLUT4 vesicles in the TIRF zone and promoted insulin-induced GLUT4 exposure to the extracellular milieu. Myo1c also contributed to insulin-dependent actin filament remodeling. Thus we propose that interaction of vesicular Myo1c with cortical actin filaments is required for insulin-mediated tethering of GLUT4 vesicles and for efficient GLUT4 surface delivery in muscle cells.
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Affiliation(s)
- Shlomit Boguslavsky
- Cell Biology Program, Hospital for Sick Children, Toronto, ON M5G 1X8, Canada
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28
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Berryhill ME, Chiu T, Hughes HC. Following the feeling: Proprioceptive smooth pursuit revisited. J Vis 2010. [DOI: 10.1167/6.6.2] [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: 11/24/2022] Open
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29
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Chiu T, Burd A. Alternative techniques of pedicle transfer. J Surg Oncol 2009; 99:456. [PMID: 19347883 DOI: 10.1002/jso.21278] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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30
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Chui L, Chiu T, Kakulphimp J, Tyrrell G. A comparison of three real-time PCR assays for the confirmation of Neisseria gonorrhoeae following detection of N. gonorrhoeae using Roche COBAS AMPLICOR. Clin Microbiol Infect 2008; 14:473-9. [DOI: 10.1111/j.1469-0691.2008.01950.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [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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31
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Chiu T, Li M, DeUgarte C, Hughes M, Hill D. P-28. Fertil Steril 2006. [DOI: 10.1016/j.fertnstert.2006.02.077] [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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32
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Chiu T, Massimi M. A digital support device designed to help family caregivers coordinate, communicate and plan the care of people with brain injury. AMIA Annu Symp Proc 2006; 2006:884. [PMID: 17238504 PMCID: PMC1839382] [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: 05/13/2023]
Abstract
This poster reports on the design concepts of a digital support device to help family caregivers coordinate care of people with brain injury. Using a user-centered design methodology, we designed a device with the following requirements: centrally located in the home; speeds up appointment decisions;simplifies communication processes; improves access to community resources; involves care-recipients in the care; and adapts to changing support needs.
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Affiliation(s)
- T Chiu
- HPME, University of Toronto; COTA Health
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33
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Chiu T, Lottridge D. Development and iterative refinement of an internet-based service for Chinese family caregivers of people with Alzheimer Disease. AMIA Annu Symp Proc 2005; 2005:919. [PMID: 16779206 PMCID: PMC1560456] [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: 05/10/2023]
Abstract
This poster reports on the developmental phase of a new internet-based support services (ICSS) for Chinese caregivers of people with Alzheimer Disease (AD): a specialized email application and an informational website. Bilingual Chinese caregivers wanted internet-based information in both Chinese and English. Usability testing and heuristic evaluation results revealed that the interface successfully supported the core functionality, but can be refined to improve usability.
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Affiliation(s)
- T Chiu
- COTA Health & University of Toronto
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34
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Creighton S, Almqvist EW, MacGregor D, Fernandez B, Hogg H, Beis J, Welch JP, Riddell C, Lokkesmoe R, Khalifa M, MacKenzie J, Sajoo A, Farrell S, Robert F, Shugar A, Summers A, Meschino W, Allingham-Hawkins D, Chiu T, Hunter A, Allanson J, Hare H, Schween J, Collins L, Sanders S, Greenberg C, Cardwell S, Lemire E, MacLeod P, Hayden MR. Predictive, pre-natal and diagnostic genetic testing for Huntington's disease: the experience in Canada from 1987 to 2000. Clin Genet 2003; 63:462-75. [PMID: 12786753 DOI: 10.1034/j.1399-0004.2003.00093.x] [Citation(s) in RCA: 126] [Impact Index Per Article: 6.0] [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: 11/23/2022]
Abstract
Predictive and pre-natal testing for Huntington's Disease (HD) has been available since 1987. Initially this was offered by linkage analysis, which was surpassed by the advent of the direct mutation test for HD in 1993. Direct mutation analysis provided an accurate test that not only enhanced predictive and pre-natal testing, but also permitted the diagnostic testing of symptomatic individuals. The objective of this study was to investigate the uptake, utilization, and outcome of predictive, pre-natal and diagnostic testing in Canada from 1987 to April 1, 2000. A retrospective design was used; all Canadian medical genetics centres and their affiliated laboratories offering genetic testing for HD were invited to participate. A total of 15 of 22 centres (68.2%), currently offering or ever having offered genetic testing for HD, responded, providing data on test results, demographics, and clinical history. A total of 1061 predictive tests, 15 pre-natal tests, and 626 diagnostic tests were performed. The uptake for predictive testing was approximately 18% of the estimated at-risk Canadian population, ranging from 12.5% in the Maritimes to 20.7% in British Columbia. There appears to have been a decline in the rate of testing in recent years. Of the predictive tests, 45.0% of individuals were found to have an increased risk, and a preponderance of females (60.2%) sought testing. A greater proportion of those at < or = 25% risk sought predictive testing once direct CAG mutation analysis had become available (10.9% after mutation analysis vs 4.7% before mutation analysis, p = 0.0077). Very few pre-natal tests were requested. Of the 15 pre-natal tests, 12 had an increased risk, resulting in termination of pregnancy in all but one. Diagnostic testing identified 68.5% of individuals to be positive by mutation analysis, while 31.5% of those with HD-like symptoms were not found to have the HD mutation. The positive diagnostic tests included 24.5% of individuals with no known prior family history of HD.
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Affiliation(s)
- S Creighton
- Provincial Medical Genetics Programme, Children's & Women's Health Center, Vancouver, British Columbia, Canada
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35
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Mullin LS, Chiu T, Kennedy GL. Initial study in rats evaluating the effects of 1,4-dichlorobutene-2 (DCB) on the respiratory tract. Drug Chem Toxicol 2002; 25:227-30. [PMID: 12024805 DOI: 10.1081/dct-120003262] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Rats were exposed by inhalation to either 0.5 ppm 1,4-dichlorobutene-2 (DCB) for two years or to 5.0 ppm for seven months, 2.5 ppm for five months, and no further exposure for 12 months prior to sacrifice. Malignant and non-malignant tumors of the nasal tissues were seen in both test groups with the incidence and proportion of malignant tumors being much higher in the 5.0/2.5 ppm rats. Under the conditions of this study, DCB is carcinogenic in rats of both sexes.
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Affiliation(s)
- L S Mullin
- E.I. du Pont de Nemours and Company, Haskell Laboratory for Health and Environmental Sciences, P.O. Box 50, Newark, DE 19714-0050, USA
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36
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Zhukova E, Sinnett-Smith J, Wong H, Chiu T, Rozengurt E. CCK(B)/gastrin receptor mediates synergistic stimulation of DNA synthesis and cyclin D1, D3, and E expression in Swiss 3T3 cells. J Cell Physiol 2002. [PMID: 11748587 DOI: 10.1002/jcp.10018].] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
In order to develop a model system for identifying signaling pathways and cell cycle events involved in gastrin-mediated mitogenesis, we have used high efficiency retroviral-mediated transfection of cholecystokinin (CCK)(B)/gastrin receptor into Swiss 3T3 cells. The retrovirally-transfected CCK(B)/gastrin receptor binds 125I-CCK-8 with high affinity (Kd = 1.1 nM) and is functionally coupled to intracellular signaling pathways including rapid and transient increase in Ca2+ fluxes, protein kinase C-dependent protein kinase D activation, and MEK-dependent ERK1/2 activation. In the presence of insulin, CCK-8 or gastrin induced a 66.5 +/- 8.8-fold (mean +/- SEM, n = 24 in eight independent experiments) increase in cellular DNA synthesis, reaching a level similar to that achieved by stimulation with a saturating concentration of fresh serum, and much greater than the response to each agonist added alone. CCK-8 also induced a striking increase in the expression of cyclins D1, D3, and E and hyperphosphorylation of Rb acting synergistically with insulin. Similar effects were observed when CCK(B)/gastrin receptor was activated in the presence of EGF or bombesin. Our results demonstrate that activation of CCK(B)/gastrin receptor retrovirally-transfected into Swiss 3T3 induces a potent synergistic effect on DNA synthesis, accumulation of cyclins D1, D3, and E and hyperphosphorylation of Rb in combination with insulin, EGF, or bombesin. Thus, the CCK(B)/gastrin receptor transfected into Swiss 3T3 cells provides a novel model system to elucidate mitogenic signal transduction pathways and cell cycle events activated via this receptor.
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Affiliation(s)
- E Zhukova
- Department of Medicine, School of Medicine and Molecular Biology Institute, University of California, Los Angeles, CA 90095-1786, USA
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37
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Zhukova E, Sinnett-Smith J, Wong H, Chiu T, Rozengurt E. CCK(B)/gastrin receptor mediates synergistic stimulation of DNA synthesis and cyclin D1, D3, and E expression in Swiss 3T3 cells. J Cell Physiol 2001. [PMID: 11748587 DOI: 10.1002/jcp.10018]] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
In order to develop a model system for identifying signaling pathways and cell cycle events involved in gastrin-mediated mitogenesis, we have used high efficiency retroviral-mediated transfection of cholecystokinin (CCK)(B)/gastrin receptor into Swiss 3T3 cells. The retrovirally-transfected CCK(B)/gastrin receptor binds 125I-CCK-8 with high affinity (Kd = 1.1 nM) and is functionally coupled to intracellular signaling pathways including rapid and transient increase in Ca2+ fluxes, protein kinase C-dependent protein kinase D activation, and MEK-dependent ERK1/2 activation. In the presence of insulin, CCK-8 or gastrin induced a 66.5 +/- 8.8-fold (mean +/- SEM, n = 24 in eight independent experiments) increase in cellular DNA synthesis, reaching a level similar to that achieved by stimulation with a saturating concentration of fresh serum, and much greater than the response to each agonist added alone. CCK-8 also induced a striking increase in the expression of cyclins D1, D3, and E and hyperphosphorylation of Rb acting synergistically with insulin. Similar effects were observed when CCK(B)/gastrin receptor was activated in the presence of EGF or bombesin. Our results demonstrate that activation of CCK(B)/gastrin receptor retrovirally-transfected into Swiss 3T3 induces a potent synergistic effect on DNA synthesis, accumulation of cyclins D1, D3, and E and hyperphosphorylation of Rb in combination with insulin, EGF, or bombesin. Thus, the CCK(B)/gastrin receptor transfected into Swiss 3T3 cells provides a novel model system to elucidate mitogenic signal transduction pathways and cell cycle events activated via this receptor.
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Affiliation(s)
- E Zhukova
- Department of Medicine, School of Medicine and Molecular Biology Institute, University of California, Los Angeles, CA 90095-1786, USA
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38
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Zhukova E, Sinnett-Smith J, Wong H, Chiu T, Rozengurt E. CCK(B)/gastrin receptor mediates synergistic stimulation of DNA synthesis and cyclin D1, D3, and E expression in Swiss 3T3 cells. J Cell Physiol 2001; 189:291-305. [PMID: 11748587 DOI: 10.1002/jcp.10018] [Citation(s) in RCA: 30] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
In order to develop a model system for identifying signaling pathways and cell cycle events involved in gastrin-mediated mitogenesis, we have used high efficiency retroviral-mediated transfection of cholecystokinin (CCK)(B)/gastrin receptor into Swiss 3T3 cells. The retrovirally-transfected CCK(B)/gastrin receptor binds 125I-CCK-8 with high affinity (Kd = 1.1 nM) and is functionally coupled to intracellular signaling pathways including rapid and transient increase in Ca2+ fluxes, protein kinase C-dependent protein kinase D activation, and MEK-dependent ERK1/2 activation. In the presence of insulin, CCK-8 or gastrin induced a 66.5 +/- 8.8-fold (mean +/- SEM, n = 24 in eight independent experiments) increase in cellular DNA synthesis, reaching a level similar to that achieved by stimulation with a saturating concentration of fresh serum, and much greater than the response to each agonist added alone. CCK-8 also induced a striking increase in the expression of cyclins D1, D3, and E and hyperphosphorylation of Rb acting synergistically with insulin. Similar effects were observed when CCK(B)/gastrin receptor was activated in the presence of EGF or bombesin. Our results demonstrate that activation of CCK(B)/gastrin receptor retrovirally-transfected into Swiss 3T3 induces a potent synergistic effect on DNA synthesis, accumulation of cyclins D1, D3, and E and hyperphosphorylation of Rb in combination with insulin, EGF, or bombesin. Thus, the CCK(B)/gastrin receptor transfected into Swiss 3T3 cells provides a novel model system to elucidate mitogenic signal transduction pathways and cell cycle events activated via this receptor.
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Affiliation(s)
- E Zhukova
- Department of Medicine, School of Medicine and Molecular Biology Institute, University of California, Los Angeles, CA 90095-1786, USA
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39
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Abstract
Protein kinase C (PKC) is implicated in the regulation of multiple important functions in intestinal epithelial cells, but the downstream signaling targets of PKCs in these cells remain poorly characterized. Here we report that treatment of normal rat intestinal cell lines IEC-6 and IEC-18 with phorbol 12,13-dibutyrate (PDBu) led to a rapid and striking PKC-dependent activation of protein kinase D (PKD; also known as PKCmu). Unlike conventional and novel PKCs, PKD did not undergo downregulation in response to prolonged (24 h) exposure of IEC-6 or IEC-18 cells to PDBu. PKD was also rapidly activated in these cells by lysophosphatidic acid (LPA) or angiotensin in a concentration-dependent fashion via a PKC-dependent pathway. EC(50) values were 0.1 microM and 2 nM for LPA and angiotensin II, respectively. LPA-induced PKD activation was prevented selectively by treatment with pertussis toxin. PKD activation was tightly associated with an increase in PKD autophosphorylation at serine 916. Our results identify PKD as a novel early point of convergence and integration of G(i) and G(q) signaling in intestinal epithelial cells.
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Affiliation(s)
- T Chiu
- Department of Medicine, UCLA School of Medicine and Molecular Biology Institute, Los Angeles, CA 90095, USA
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40
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Abstract
Addition of gastrin or cholecystokinin octapeptide (CCK-8) to cultures of Rat-1 cells stably transfected with the CCK2 (CCK(B)/gastrin) receptor induced protein kinase D (PKD) activation that was detectable within 1 min and reached a maximum ( approximately 10-fold) after 2.5 min of hormonal stimulation. Half-maximal PKD activation for both CCK-8 and gastrin was achieved at 10 nM. Treatment with various concentrations of the selective PKC inhibitors Ro 31-8220 or GF-I potently blocked PKD activation induced by subsequent addition of CCK-8 in a concentration-dependent fashion. Our results indicate that PKC-dependent PKD activation is a novel early event in the action of gastrin and CCK-8 via CCK2 receptors.
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Affiliation(s)
- T Chiu
- Department of Medicine, UCLA School of Medicine and Molecular Biology Institute, 900 Veteran Avenue, Warren Hall, Room 11-124, University of California, Los Angeles, CA 90095-1786, USA
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Malley LA, Bamberger JR, Stadler JC, Elliott GS, Hansen JF, Chiu T, Grabowski JS, Pavkov KL. Subchronic toxicity of cyclohexane in rats and mice by inhalation exposure. Drug Chem Toxicol 2000; 23:513-37. [PMID: 11071393 DOI: 10.1081/dct-100101969] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Inhalation studies were conducted to determine the potential toxicity and/or potential neurotoxicity of cyclohexane. Groups of rats and mice were exposed to 0, 500, 2000, or 7000 ppm concentrations of cyclohexane vapor 6 hr/day, 5 days/week for 14 weeks. Subgroups of rats and mice were further observed during a 1-month recovery period. Functional observational battery (FOB) and motor activity (MA) behavioral tests were conducted on rats. These tests were conducted prior to the exposure series and during weeks 4, 8, and 13 on non-exposure days. Clinical pathology evaluations were conducted after approximately 7, 13, and 18 weeks. Approximately 14 and 18 weeks after study initiation, tissues from rats and mice were histologically processed and evaluated by light microscopy. During exposure to 2000 or 7000 ppm, rats and mice had a diminished response or an absent response to delivery of a punctate auditory alerting stimulus. Immediately following removal of rats from the inhalation chambers, 7000 ppm males and females and 2000 ppm females displayed a compound-related increase in the incidence of wet and/or stained fur (which occurred in the areas of the mouth, chin, and/or perineum). These signs were transient, were not observed during exposure or prior to exposure the following day, and were not associated with any behavioral or morphological changes. During exposure sessions, mice exposed to 7000 ppm exhibited clinical signs of toxicity which included hyperactivity, circling, jumping/hopping, excessive grooming, kicking of rear legs, standing on front legs, and occasional flipping behavior. Clinical signs of toxicity observed in 7000 ppm mice immediately after exposure included hyperactivity, hyperreactivity, ruffled fur (females only), gait abnormalities, spasms in both rear legs, and excessive grooming (males only). The clinical signs observed in mice during and immediately after exposure were transient, and were not present prior to the subsequent exposure. A few mice exposed to 2000 ppm appeared hyperactive during exposure in the latter portion of the study. There were no compound-related changes in mean body weights, body weight gains, food consumption, food efficiency, or mortality; and there were no ophthalmological abnormalities in rats or mice. In addition, there were no compound-related effects on 37 different behavioral parameters assessed during the FOB or during motor activity tests in rats. Male and female mice exposed to 7000 ppm had slight increases in measures of circulating erythrocyte mass (red blood cells, hemoglobin, hematocrit) and plasma protein concentration (males only). Male rats and male and female mice exposed to 7000 ppm had significantly increased relative liver weights, and 7000 ppm male mice also had significantly increased absolute liver weights at the end of the exposure period. At the end of the 1-month recovery period, absolute and relative liver weights of male and female mice were similar to control. However, relative liver weights of 7000 ppm male rats continued to be significantly higher at the end of the recovery period. Male and female rats exposed to 7000 ppm had a significantly increased incidence of hepatic centrilobular hypertrophy at the end of the exposure period, which was not observed at the conclusion of the 1-month recovery period. No microscopic changes were observed in mice. In rats, the no-observed-effect level (NOEL) for acute, transient effects was 500 ppm based on a diminished/absent response to an auditory alerting stimulus at 2000 ppm and above. The NOEL for subchronic toxicity in rats was 7000 ppm based on the lack of adverse effects on body weight, clinical chemistry, tissue morphology, and neurobehavioral parameters. In mice, the NOEL for acute, transient effects was 500 ppm based on behavioral changes during exposure at 2000 ppm and above. The NOEL for subchronic toxicity in mice is 2000 ppm based on hematological changes at 7000 ppm.
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Affiliation(s)
- L A Malley
- E. I. du Pont de Nemours and Company Haskell Laboratory for Toxicology and Industrial Medicine, Newark, Delaware 19714, USA
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Tien PC, Chiu T, Latif A, Ray S, Batra M, Contag CH, Zejena L, Mbizvo M, Delwart EL, Mullins JI, Katzenstein DA. Primary subtype C HIV-1 infection in Harare, Zimbabwe. J Acquir Immune Defic Syndr Hum Retrovirol 1999; 20:147-53. [PMID: 10048901 DOI: 10.1097/00042560-199902010-00006] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Heterosexual transmission of HIV-1 is widespread in Southern Africa. Heteroduplex mobility assays (HMA) and phylogenetic analyses of V3-V5 envelope (env) gene sequences demonstrate that subtype C predominates in Zimbabwe. To elucidate factors contributing to the epidemic in Zimbabwe, clinical and virologic characteristics of recently acquired subtype C HIV-1 infection among 21 men and 1 woman were determined. In 12 of 19 men providing clinical histories, a sexually transmitted infection preceded serologic evidence of HIV-1, and 14 of 19 men complained of rash or fever before seroconversion. Quantitative p24 antigen levels, reverse transcriptase activity, and HIV RNA levels of 22 viral isolates correlated with in vitro infectivity in peripheral blood mononuclear cells (p < .05). Biologic phenotype assessed in MT-2 cells demonstrated that 3 of 22 isolates (14%) were syncytia inducing (SI) and the remaining 19 nonsyncytium inducing (NSI). Early growth of virus in culture was associated with increased plasma HIV RNA levels, decreased CD4 cell levels, and SI virus. Recent subtype C HIV-1 infection through heterosexual transmission in Zimbabwe demonstrated clinical and virologic features consistent with reports of seroconversion to subtype B viruses.
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Affiliation(s)
- P C Tien
- Stanford University Medical Center, Center for AIDS Research, California 94305, USA
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Abstract
A8947 is a member of the sulfonyl urea class of compounds and is the active ingredient in a commercial broad leaf herbicide. This compound has been shown to produce pancreatic hypertrophy in rats, mice, and dogs. The objectives of this study were to investigate the mechanism(s) for the A8947 induction of pancreatic acinar cell hypertrophy and proliferation and to evaluate whether these pancreatic changes are reversible. A8947 was fed to male Crl:CD BR rats for up to 28 days (0, 300, 10,000, 30,000 ppm) or 56 days (0, 30,000 ppm). Rats were terminated on Test Days 7, 14, and 28 to assess the time course and dose response for the A8947-induced pancreatic changes, while rats terminated on Test Day 56 were used to assesss the reversibility of the pancreas effects at 30,000 ppm A8947. A8947 produced significant increases in pancreatic weight and acinar cell proliferation and diffuse acinar cell hypertrophy in 7 days at 10,000 and 30,000 ppm dose levels. By Day 14, absolute pancreas weights in the 10,000 and 30,000 ppm groups were maximally increased and remained at these levels throughout the study. In contrast, acinar cell proliferation in the 30,000 ppm group was still elevated at Test Day 14, but attenuated relative to the 7-day response, and returned to control levels by Test Day 28. No effects were observed at 300 ppm after a 28-day exposure period, while complete reversibility of A8947-induced pancreatic effects was demonstrated at 30,000 ppm following a 1-month recovery period (Test Day 56). Cholecystokinin (CCK) levels were increased by A8947 and closely followed the time course for pancreatic changes. MK-329, a specific CCKA receptor antagonist, completely ablated the ability of 30,000 ppm A8947 to increase pancreas weight following 7 days of exposure. A8947 did not bind the CCKA receptor in a receptor competition assay, negating any potential agonist mechanism. A8947 did, however, inhibit trypsin in vitro, suggesting a mechanism of action similar to that of raw soy protein, in which trypsin inhibition in vivo results in increased CCK levels followed by pancreatic acinar cell hypertrophy and proliferation.
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Affiliation(s)
- J D Obourn
- Haskell Laboratory for Toxicology and Industrial Medicine, E. I. du Pont de Nemours & Company, Elkton Road, Newark, Delaware 19714, USA
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Chiu T, Johnson R, Dickerson RE. DNA-specific binding by HIN and FIS. Acta Crystallogr A 1996. [DOI: 10.1107/s0108767396093051] [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 T, Reid IA. Role of cyclic GMP-inhibitable phosphodiesterase and nitric oxide in the beta adrenoceptor control of renin secretion. J Pharmacol Exp Ther 1996; 278:793-9. [PMID: 8768733] [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] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
We have reported that inhibition of nitric oxide synthesis with N(G)-nitro-L-arginine methyl ester (L-NAME) attenuates the renin secretory response to beta adrenoceptor stimulation. We proposed that the attenuation results from disinhibition of the cyclic GMP-inhibitable isoform of phosphodiesterase (PDE III) with a resultant increase in cyclic AMP hydrolysis in the juxtaglomerular cells. In our investigation, experiments were performed in conscious rabbits to test the effects of the specific PDE III inhibitor milrinone on resting renin secretion and on the renin responses to isoproterenol and L-NAME. In the first series of experiments, infusion of milrinone increased plasma renin activity from 5.4 +/- 0.6 to 10.2 +/- 1.4 ng/ml/2 hr (P < .01). Heart rate increased markedly, but arterial pressure did not change. In the second series, infusion of isoproterenol increased plasma renin activity from 6.3 +/- 1.1 to 15.0 +/- 1.0 ng/ml/2 hr (P < .01). The renin response to isoproterenol was increased (P < .01) in the presence of milrinone (15.3 +/- 3.7 to 38.4 +/- 6.2 ng/ml/2 hr, P < .01). In the third series, L-NAME alone decreased plasma renin activity from 5.0 +/- 1.0 to 3.3 +/- 1.0 ng/ml/2 hr (P < .01). Milrinone again increased plasma renin activity and prevented the suppression of plasma renin activity by L-NAME. By contrast, milrinone did not alter the suppression of plasma renin activity produced by infusion of phenylephrine. In addition, a PDE IV inhibitor failed to prevent the suppression of PRA by L-NAME. Finally, administration of milrinone completely reversed the L-NAME-induced suppression of the renin response to isoproterenol. These results provide evidence that PDE III participates in the regulation of renin secretion, and support the proposal that the L-NAME-induced reductions in renin secretion and in the renin response to beta adrenoceptor stimulation result from disinhibition of PDE III and increased hydrolysis of cyclic AMP in the juxtaglomerular cells.
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Affiliation(s)
- T Chiu
- Department of Physiology, University of California, San Francisco, USA
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Abstract
Nitric oxide plays an important role in the regulation of arterial pressure by its actions to dilate vascular smooth muscle, alter sympathetic neural activity, and modulate the vasoconstrictor action of norepinephrine, angiotensin II and vasopressin. Nitric oxide may also influence blood pressure regulation by altering the secretion of renin and vasopressin. To test this possibility, we investigated the effects of inhibiting nitric oxide synthesis on the cardiovascular, renin and vasopressin responses to hypotensive hemorrhage, a situation in which the renin-angiotensin system and vasopressin contribute significantly to the control of blood pressure. Arterial blood was withdrawn from conscious, chronically-prepared rabbits at 1.0 ml/kg/min for 15 min under control conditions, and during i.v. infusion of the nitric oxide synthase inhibitor L-NAME. Hemorrhage decreased mean arterial pressure from 69 +/- 2 to 45 +/- 4 mm Hg (p < 0.01) and increased heart rate from 211 +/- 10 to 270 +/- 15 bpm (p < 0.05). Plasma renin activity increased from 7.7 +/- 1 to 36.1 +/- 9.6 ng/ml/2h at 15 min (p < 0.01), while plasma vasopressin concentration increased from 1.7 +/- 0.6 to 183.2 +/- 98.5 pg/ml (p < 0.05). Infusion of L-NAME increased blood pressure and plasma vasopressin concentration, and decreased heart rate and plasma renin activity. L-NAME markedly attenuated the hypotensive response to hemorrhage (72 +/- 3 to 62 +/- 4 mmHg), but did not alter the increases in heart rate, plasma renin activity or plasma vasopressin concentration. In separate experiments, L-NAME did not alter the setpoint or gain of the baroreceptor reflex control of heart rate.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- T Chiu
- Department of Physiology, University of California, San Francisco 94143-0444, USA
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Carzoli RP, Martinez-Cruz M, Cuevas LL, Murphy S, Chiu T. Comparison of neonatal nurse practitioners, physician assistants, and residents in the neonatal intensive care unit. Arch Pediatr Adolesc Med 1994; 148:1271-6. [PMID: 7951805 DOI: 10.1001/archpedi.1994.02170120033005] [Citation(s) in RCA: 56] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
OBJECTIVE To compare patient care delivery by neonatal nurse practitioners and physician assistants with that of pediatric residents in the intensive care setting. DESIGN Retrospective chart review after developing specific performance criteria, namely, patient management, outcome, and charges. METHODS/MATERIALS Charts for 244 consecutive admissions to a neonatal intensive care unit in Jacksonville, Fla, were reviewed. Patients were cared for by one of two teams, one staffed by residents and the other by neonatal nurse practitioners and physician assistants. Similar patients were cared for by the two teams, as determined by patient background characteristics and diagnostic variables. Performance of the two teams was assessed by comparison of patient management, outcome, and charges. Management variables included data on length of critical care and hospital stay, ventilator and oxygen use, total parenteral nutritional use, number of transfusions, and the performance of various procedures. Outcome variables included the incidence of air leaks, bronchopulmonary dysplasia, intraventricular hemorrhage, patent ductus arteriosus, necrotizing enterocolitis, retinopathy of prematurity, and number of infants who died. Charge variables included hospital and physician charges. MAIN RESULTS Results demonstrated no significant differences in management, outcome, or charge variables between patients cared for by the two teams. CONCLUSION Neonatal nurse practitioners and physician assistants are an effective alternative to residents for patient care in the neonatal intensive care unit.
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Affiliation(s)
- R P Carzoli
- Department of Pediatrics, University of Florida Health Science Center, Jacksonville
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Abstract
The divalent cation-induced protein folding properties of the template macromolecule, bovine dentine phosphophoryn (BDPP), have been examined by 1H/31P/13C/113Cd-nmr spectroscopy. Cd(II) was employed, exploiting the sensitivity of 113Cd-nmr to ligand-binding interactions and kinetics. Cation binding was studied over the stoichiometric range of 0-50: 1 Cd(II): protein (mole ratio), well below the range of Cd(II) concentration required to induce protein precipitation. The stepwise titration of divalent cation-depleted phosphophoryn at pH 7.2 in H2O/D2O with 113CdCl2 revealed that (PSer)n, (PSerAsp)n, and (Asp)n polyelectrolyte cation-binding domains undergo two major transitions in their secondary and tertiary structures: the first transition, occurring between 1:10 and 1:1 Cd(II): protein stoichiometry, and the second, between 10:1 and 50:1. By monitoring the amide NH intensities, 31P-nmr chemical shift, and 13C Asp-C, resonances, it was concluded that Cd(II) ions exhibit a binding-site preference for polyelectrolyte cation-binding domains, in the order (PSer)n > (PSerAsp)n > (Asp)n This preference correlates with the degree of negative charge density for each sequence motif. Accompanying the backbone conformational transitions at the polyelectrolyte regions were conformational transitions in the flanking hinge domains, indicating that the hinge domains participate in the folding of the phosphophoryn molecule as divalent cation binding occurs at the polyelectrolyte domains. We were unsuccessful in detecting phosphophoryn-bound Cd(II) species by 113Cd-nmr because of chemical exchange modulation. However, using a smaller 21-residue peptide mimetic of phosphophoryn, we have observed three stoichiometric-dependent 113Cd resonances that differ in terms of the oxoanion coordination number. Our observation of multiple Cd(II) species in the presence of the peptide supports our contention that Cd(II) has many chemically distinct coordination sites on phosphophoryn, each in multiple equilibria with H2O, Cl-, and side-chain oxoatoms.
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Affiliation(s)
- J S Evans
- Arthur Amos Noyes Laboratory of Chemical Physics, Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena 91125
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Vaughn AJ, Carzoli RP, Sanchez-Ramos L, Murphy S, Khan N, Chiu T. Community-wide estimation of illicit drug use in delivering women: prevalence, demographics, and associated risk factors. Obstet Gynecol 1993; 82:92-6. [PMID: 8515933] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
OBJECTIVE To determine the community-wide prevalence of illicit drug use in delivering women and to compare rates in women delivering in an urban center serving the medically indigent with those delivering in private hospitals. METHODS Over 6 weeks, 1062 urine samples were obtained anonymously from women presenting for delivery in seven hospitals in the Jacksonville, Florida area. All urine samples were analyzed blindly for illicit drugs using fluorescent polarized immunoassay. RESULTS The percentage of women with positive urine toxicology was 7.1%. Positive results were more frequent in the public hospital population (12.7%) than the private hospital population (3.9%). The prevalence of cocaine use was 2.1% and marijuana 5.3%. Urine positivity was similar in black and white women, with cocaine metabolites more prevalent in black women and cannabinoids more common in white women. Women with positive screens for cocaine were more likely to use tobacco and alcohol, admit to substance abuse, and receive limited prenatal care. Women with positive screens for marijuana were difficult to differentiate from the urine-toxicology-negative group. CONCLUSIONS Urine samples positive for illicit drugs were significantly more common in women delivering in an urban center serving the indigent population than in those delivering in private hospitals. Based on associated factors, cocaine users fit a more indentifiable profile than marijuana users. The overall incidence of positive urine toxicology was no different in black and white pregnant women, but the more frequent finding of cocaine metabolites in black women may lead to biased over-reporting of substance abuse in this population.
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Affiliation(s)
- A J Vaughn
- Department of Pediatrics, University of Florida Health Science Center, Jacksonville
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Chiu T, Brennan L. University neonatal centers and level II centers compatibility. Jacksonville experience. J Fla Med Assoc 1992; 79:464-8. [PMID: 1500924] [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: 12/27/2022]
Abstract
Reported are 10 years experience in the development of a Citywide Neonatal Program in the Jacksonville area, which could be helpful as a model for establishing relationships between academic centers and outside Level II nurseries. The four phases of development are documented. An analysis of the financial impact to the academic program is presented and also an outline of the gain realized by the Department of Pediatrics, University of Florida Health Science Center. The positive results in amalgamation of the neonatal services in Jacksonville have far outweighed any potential harmful effects from competition between an academic center and other private nurseries in the city.
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Affiliation(s)
- T Chiu
- Department of Pediatrics, University of Florida Health Science Center, Jacksonville
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