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Tenge V, Vijayalakshmi Ayyar B, Ettayebi K, Crawford SE, Shen YT, Neill FH, Atmar RL, Estes MK. Bile acid-sensitive human norovirus strains are susceptible to sphingosine-1-phosphate receptor 2 inhibition. bioRxiv 2024:2024.01.02.573926. [PMID: 38260626 PMCID: PMC10802320 DOI: 10.1101/2024.01.02.573926] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2024]
Abstract
Human noroviruses (HuNoVs) are a diverse group of RNA viruses that cause both endemic and pandemic acute viral gastroenteritis. Previously we reported that many strains of HuNoV require bile or bile acid (BA) to infect human jejunal intestinal enteroid cultures. Of note, BA was not essential for replication of a pandemic-causing GII.4 HuNoV strain. Using the BA-requiring strain GII.3, we found that the hydrophobic BA GCDCA induces multiple cellular responses that promote replication in jejunal enteroids. Further, we found that chemical inhibition of the G-protein coupled receptor, sphingosine-1- phosphate receptor 2 (S1PR2), by JTE-013 reduced both GII.3 infection in a dose- dependent manner and cellular uptake in enteroids. Herein, we sought to determine if S1PR2 is required by other BA-dependent HuNoV strains and BA-independent GII.4, and if S1PR2 is required for BA-dependent HuNoV infection in other segments of the small intestine. We found JTE-013 inhibition of S1PR2 in jejunal HIEs reduces GI.1, GII.3, and GII.17 (BA-dependent) but not the GII.4 Sydney variant (BA-independent) infection, providing additional evidence of strain-specific differences in HuNoV infection. GII.3 infection of duodenal, jejunal and ileal lines derived from the same individual was also reduced with S1PR2 inhibition, indicating a common mechanism of BA-dependent infection among multiple segments of the small intestine. Our results support a model where BA-dependent HuNoV exploit the activation of S1PR2 by BA to infect the entire small intestine. Importance Human noroviruses (HuNoVs) are important viral human pathogens that cause both outbreaks and sporadic gastroenteritis. These viruses are diverse, and many strains are capable of infecting humans. Our previous studies have identified strain-specific requirements for hydrophobic bile acids (BAs) to infect intestinal epithelial cells. Moreover, we identified a BA receptor, sphingosine-1-phosphate receptor 2 (S1PR2), required for infection by a BA-dependent strain. To better understand how various HuNoV strains enter and infect the small intestine and the role of S1PR2 in HuNoV infection, we evaluated infection by additional HuNoV strains using an expanded repertoire of intestinal enteroid cell lines. We found that multiple BA-dependent strains, but not a BA- independent strain, all required S1PR2 for infection. Additionally, BA-dependent infection required S1PR2 in multiple segments of the small intestine. Together these results indicate S1PR2 has value as a potential therapeutic target for BA-dependent HuNoV infection.
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Shen YT, Guan M. [Application of plasma SARS-CoV-2 quantitative antigen detection in the diagnosis and treatment of COVID-19]. Zhonghua Yu Fang Yi Xue Za Zhi 2023; 57:2232-2238. [PMID: 38186181 DOI: 10.3760/cma.j.cn112150-20230711-00003] [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: 01/09/2024]
Abstract
The corona virus disease 2019(COVID-19) pandemic, caused by the severe acute respiratory syndrome coronavirus 2(SARS-CoV-2), has created an urgent need of scientific and effective biomarkers for the purpose of prevention and control. Currently, commonly employed viral nucleic acids, antibodies, and rapid antigen test detection technologies all exhibit a range of limitations, including restricted applicability, inadequate sensitivity and specificity. Plasma SARS-CoV-2 quantitative antigen, as an emerging biomarker, has garnered significant attention due to its potential clinical value in the diagnosis and management of COVID-19. This article comprehensively analyzes the principles and clinical applications of quantitative detection technology for plasma SARS-CoV-2 antigen. Additionally, it explores the challenges encountered in this field and provides insights into future prospects.
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Affiliation(s)
- Y T Shen
- Department of Laboratory Medicine, Huashan Hospital, Fudan University, Shanghai 200040, China
| | - M Guan
- Department of Laboratory Medicine, Huashan Hospital, Fudan University, Shanghai 200040, China
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Abstract
Manipulating active sites of catalysts is crucial but challenging in catalysis science and engineering. Beyond the design of the composition and structure of catalysts, the confined electromagnetic field in optical cavities has recently become a promising method for catalyzing chemical reactions via strong light-matter interactions. Another form of confined electromagnetic field, the charge density wave in plasmonic cavities, however, still needs to be explored for catalysis. Here, we present an unprecedented catalytic mode based on plasmonic cavities, called plasmonic cavity-catalysis. We achieve direct control of catalytic sites in plasmonic cavities through standing hot carrier waves. Periodic catalytic hotspots are formed because of localized energy and carrier distribution and can be well tuned by cavity geometry, charge density, and excitation angle. We also found that the catalytic activity of the cavity mode increases several orders of magnitude compared with conventional plasmonic catalysis. We ultimately demonstrate that the locally concentrated long-lived hot carriers in the standing wave mode underlie the formation of the catalytic hotspots. Plasmonic cavity-catalysis provides a new approach to manipulate the catalytic sites and rates and may expand the frontier of heterogeneous catalysis.
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Affiliation(s)
- Pin-Tian Lyu
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China
| | - Li-Xin Yin
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China
| | - Yi-Ting Shen
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China
| | - Zhaoshuai Gao
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China
| | - Hong-Yuan Chen
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China
| | - Jing-Juan Xu
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China
| | - Bin Kang
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China
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Ji XS, Zuo HD, Shen YT, Hao WJ, Tu SJ, Jiang B. Electrochemical selective annulative amino-ketalization and amino-oxygenation of 1,6-enynes. Chem Commun (Camb) 2022; 58:10420-10423. [PMID: 36043317 DOI: 10.1039/d2cc03922b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A new electrochemical selective annulative amino-ketalization and amino-oxygenation of 1,6-enynes with disulfonimides and alcohols is reported, producing a series of functionalized benzofurans under catalyst- and oxidant-free conditions. The annulative aminoketalization proceeds with simple short-chain alcohols such as methanol, ethanol and n-propanol as O-nucleophilic reagents, while the reaction occurs in the annulative aminooxygenation direction in the presence of water and large steric sec-butyl alcohol (SBA).
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Affiliation(s)
- Xiao-Shuang Ji
- School of Chemistry & Materials Science, Jiangsu Normal University, Xuzhou, 221116, P. R. China.
| | - Hang-Dong Zuo
- School of Chemistry & Materials Science, Jiangsu Normal University, Xuzhou, 221116, P. R. China. .,School of Environmental and Safety Engineering, Changzhou University, Changzhou, 213164, Jiangsu, P. R. China
| | - Yi-Ting Shen
- School of Chemistry & Materials Science, Jiangsu Normal University, Xuzhou, 221116, P. R. China.
| | - Wen-Juan Hao
- School of Chemistry & Materials Science, Jiangsu Normal University, Xuzhou, 221116, P. R. China.
| | - Shu-Jiang Tu
- School of Chemistry & Materials Science, Jiangsu Normal University, Xuzhou, 221116, P. R. China.
| | - Bo Jiang
- School of Chemistry & Materials Science, Jiangsu Normal University, Xuzhou, 221116, P. R. China.
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Cheong PL, Tsai JM, Wu YT, Lu L, Chiu YL, Shen YT, Li YJ, Tsao CH, Wang YC, Chang FM, Huang YH, Sun CW. Cultural Adaptation and Validation of Mullen Scales of Early Learning in Taiwanese children with Autism Spectrum Disorder, Global Developmental Delay, and Typically Developing Children. Res Dev Disabil 2022; 122:104158. [PMID: 35032783 DOI: 10.1016/j.ridd.2021.104158] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2021] [Revised: 11/09/2021] [Accepted: 12/23/2021] [Indexed: 05/22/2023]
Abstract
BACKGROUND The Mullen Scales of Early Learning (MSEL) is a standardized comprehensive developmental assessment tool for children aged 0-68 months. However, few Asia-based studies have explored cultural and linguistic adaptations of the MSEL or investigated its psychometric properties in populations with autism spectrum disorder (ASD). AIMS This study evaluated the reliability and validity of the MSEL-Taiwan version (MSEL-T) for Taiwanese children with ASD, global developmental delay (GDD), and typical development (TD). METHODS AND PROCEDURES The MSEL items were translated and modified according to the language and culture in Taiwan. In total, 191 children (ASD, 69; GDD, 36; and TD, 86) aged 19-68 months were assessed using the MSEL-T and Peabody Developmental Motor Scales 2 (PDMS-2) at enrollment, followed by the assessments of Vineland Adaptive Behavior Scale-Chinese version (VABS-C) at the age of 36 months or later. OUTCOMES AND RESULTS All subscales were verified to have good interrater reliability and internal consistency, and subscale scores indicated moderate to high correlations with PDMS-2 and VABS-C scores. Significant differences in MSEL-T scores were observed between same-aged pairs of children with TD and GDD and between pairs of children with TD and ASD. CONCLUSIONS AND IMPLICATIONS The findings provide evidence of validity and reliability of the MSEL-T. And it is suggested that the culturally and linguistically adapted MSEL-T is a good tool for the clinical assessment of children with and without ASD.
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Affiliation(s)
- Pou-Leng Cheong
- Department of Pediatrics, National Taiwan University Hospital Hsin-Chu Hospital, No. 25, Lane 442, Sec. 1, Jingguo Rd., Hsinchu City, 300, Taiwan, ROC; Department of Photonics, College of Electrical and Computer Engineering, National Yang Ming Chiao Tung University, 1001 University Road, Hsinchu, 300, Taiwan, ROC; Department of Biological Science and Technology, National Yang Ming Chiao Tung University, Hsinchu, Taiwan, ROC
| | - Jung-Mei Tsai
- Department of Psychology, National Taiwan University, No. 1, Sec. 4, Roosevelt Rd., Taipei, 10617, Taiwan, ROC
| | - Yen-Tzu Wu
- School and Graduate Institute of Physical Therapy, College of Medicine, National Taiwan University, No. 1, Sec. 4, Roosevelt Rd., Taipei, 10617, Taiwan, ROC; Department of Physical Medicine and Rehabilitation, National Taiwan University Hospital, No. 1, Changde St., Zhongzheng Dist., Taipei City, 100229, Taiwan, ROC.
| | - Lu Lu
- Department of Physical Medicine and Rehabilitation, National Taiwan University Hospital, No. 1, Changde St., Zhongzheng Dist., Taipei City, 100229, Taiwan, ROC
| | - Yi-Lun Chiu
- Department of Social Work, National Taiwan University, No. 1, Sec. 4, Roosevelt Rd., Taipei, 10617, Taiwan, ROC
| | - Yi-Ting Shen
- Department of Psychology, Kaohsiung Medical University, No. 100, Shih-Chuan 1st Road, Sanmin Dist., Kaohsiung City, 80708, Taiwan, ROC
| | - Yao-Jen Li
- Insititute of Epidemiology and Prevention Medicine, National Taiwan University, No. 1, Sec. 4, Roosevelt Rd., Taipei, 10617, Taiwan, ROC
| | - Chih-Hsuan Tsao
- Department of Psychology, National Taiwan University, No. 1, Sec. 4, Roosevelt Rd., Taipei, 10617, Taiwan, ROC; Department of Foreign Languages and Literatures, National Taiwan University, No. 1, Sec. 4, Roosevelt Rd., Taipei, 10617, Taiwan, ROC
| | - Yi-Chung Wang
- School and Graduate Institute of Physical Therapy, College of Medicine, National Taiwan University, No. 1, Sec. 4, Roosevelt Rd., Taipei, 10617, Taiwan, ROC
| | - Fu-Mei Chang
- Department of Clinical Psychology, Songde Branch, Taipei City Hospital, No. 145, Zhengzhou Rd., Datong Dist., Taipei City, 10341, Taiwan, ROC
| | - Yen-Hsun Huang
- Being Alive Clinic, 1F., No. 6-1, Ln. 38, Sec. 2, Nangang Rd., Nangang Dist., Taipei City, 115028, Taiwan, ROC; Department of Clinical Psychology, Fu Jen Catholic University, No. 510, Zhongzheng Rd., Xinzhuang Dist., New Taipei City, 242062, Taiwan, ROC
| | - Chia-Wei Sun
- Department of Photonics, College of Electrical and Computer Engineering, National Yang Ming Chiao Tung University, 1001 University Road, Hsinchu, 300, Taiwan, ROC
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Lu J, Lu XY, Shen YT, Zhang LP, Mei KW, Guan BC, Lu YH. [Analysis on vaccination willingness and related factors of influenza, pneumonia, and herpes zoster vaccine among people over 50 years old in Minhang district of Shanghai]. Zhonghua Yu Fang Yi Xue Za Zhi 2022; 56:125-131. [PMID: 35184439 DOI: 10.3760/cma.j.cn112150-20210423-00406] [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: 06/14/2023]
Abstract
Objective: To determine the knowledge of influenza, pneumonia, herpes zoster and related vaccines, willingness to vaccinate under multiple payment scenarios, and corresponding risk factors among people over 50 years old in Minhang District of Shanghai. Methods: A total of 1 672 respondents aged 50-69 from 13 communities/towns in Minhang district of Shanghai were included in this study using a stratified random sampling strategy on December 2020. The knowledge of influenza, pneumonia, herpes zoster and vaccines was investigated using a questionnaire, and the differences in the willingness under multiple payment scenarios were determined using chi-square test. The consistency in the willingness under multiple payment scenarios was compared using Cohen's Kappa and the risk factors of the willingness was determined using ordinal logistic regression. Results: The average age of 1 672 respondents was (60.48±5.96) years old, including 777 (46.47%) males and 895 (53.53%) females. A total of 1 350 subjects (80.74%) had local household registration in Shanghai. The proportion of the willingness to vaccinate for themselves, spouses, and parents under any payment scenario was determined to be 80.6% (influenza vaccine), 81.5% (pneumonia vaccine), and 74.0% (herpes zoster vaccine). The willingness to vaccinate against influenza and pneumonia under multiple payment scenarios remained stable (Kappa value ≥0.6), while that against herpes zoster infection was inconsistent (Kappa value ≤0.35). Logistic regression analysis showed that respondents who had higher knowledge of influenza and influenza vaccine [OR (95%CI): 1.111 (1.054-1.170), 1.182 (1.126-1.240), respectively], aged 50-59 [1.305 (1.085-1.531)] and local household registration in Shanghai [1.372 (1.079-1.721)] had higher willingness to vaccinate against influenza, while males had lower willingness [0.733 (0.551-0.910)]. Respondents who had higher knowledge of pneumonia and pneumonia vaccine [OR (95%CI): 1.837 (1.152-2.517), 2.217 (1.541-2.893), respectively] had higher willingness to receive pneumonia vaccine. Respondents aged 50-59 [1.327 (1.059-1.537)] and with local household registration in Shanghai [2.497 (1.417-4.400)] were more likely to be vaccinated against herpes zoster, while those with middle school degree or below [0.664 (0.396-0.992)] and high school degree [0.559 (0.324-0.964)] were less likely to be vaccinated. Conclusion: Among people aged over 50 years old in Minhang district of Shanghai, the willingness to vaccinate for themselves, spouses, and parents against influenza, pneumonia and herpes zoster infection is quite different under multiple payment scenarios, especially for herpes zoster vaccine.
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Affiliation(s)
- J Lu
- Department of Immunization Planning, Minhang Center for Disease Control and Prevention, Shanghai 201101, China Minhang Branch, Fudan School of Public Health, Shanghai 201100, China
| | - X Y Lu
- Department of Epidemiology, Ministry of Education Key Laboratory of Public Health Safety, Fudan School of Public Health, Shanghai 200032, China
| | - Y T Shen
- Department of Laboratory Medicine, Huashan Hospital, Fudan University, Shanghai 200040, China
| | - L P Zhang
- Department of Immunization Planning, Minhang Center for Disease Control and Prevention, Shanghai 201101, China Minhang Branch, Fudan School of Public Health, Shanghai 201100, China
| | - K W Mei
- Department of Immunization Planning, Minhang Center for Disease Control and Prevention, Shanghai 201101, China Minhang Branch, Fudan School of Public Health, Shanghai 201100, China
| | - B C Guan
- Department of Epidemiology, Ministry of Education Key Laboratory of Public Health Safety, Fudan School of Public Health, Shanghai 200032, China
| | - Y H Lu
- Department of Epidemiology, Ministry of Education Key Laboratory of Public Health Safety, Fudan School of Public Health, Shanghai 200032, China
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Wang SC, Shen YT, Zhang TS, Hao WJ, Tu SJ, Jiang B. Cyclic Oxime Esters as Deconstructive Bifunctional Reagents for Cyanoalkyl Esterification of 1,6-Enynes. J Org Chem 2021; 86:15488-15497. [PMID: 34664501 DOI: 10.1021/acs.joc.1c01972] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
A concise copper catalysis strategy for the addition-cyclization of cyclic oxime esters across 1,6-enynes with high stereoselectivity to generate 1-indanones bearing an all-carbon quaternary center is reported. In this process, single-electron reduction of cyclic oxime esters enables deconstructive carbon-carbon cleavage to provide a key cyanopropyl radical poised for the addition-cyclization. This reaction is redox-neutral, exhibits good functional group compatibility, and features 100% atomic utilization. This process driven by copper catalyst makes readily available cyclic oxime esters as bifunctional reagents to demonstrate convergent synthesis.
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Affiliation(s)
- Shi-Chao Wang
- School of Chemistry & Materials Science, Jiangsu Key Laboratory of Green Synthetic Chemistry for Functional Materials, Jiangsu Normal University, Xuzhou 221116, P. R. China
| | - Yi-Ting Shen
- School of Chemistry & Materials Science, Jiangsu Key Laboratory of Green Synthetic Chemistry for Functional Materials, Jiangsu Normal University, Xuzhou 221116, P. R. China
| | - Tian-Shu Zhang
- School of Materials and Chemical Engineering, Xuzhou University of Technology, Xuzhou 221018, P. R. China
| | - Wen-Juan Hao
- School of Chemistry & Materials Science, Jiangsu Key Laboratory of Green Synthetic Chemistry for Functional Materials, Jiangsu Normal University, Xuzhou 221116, P. R. China
| | - Shu-Jiang Tu
- School of Chemistry & Materials Science, Jiangsu Key Laboratory of Green Synthetic Chemistry for Functional Materials, Jiangsu Normal University, Xuzhou 221116, P. R. China
| | - Bo Jiang
- School of Chemistry & Materials Science, Jiangsu Key Laboratory of Green Synthetic Chemistry for Functional Materials, Jiangsu Normal University, Xuzhou 221116, P. R. China
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Shen YT, Chen H, Jiao XM, Yang DH, Xu JM, Kuang XY. [The value of MRI in early diagnosis of dysbaric osteonecrosis]. Zhonghua Lao Dong Wei Sheng Zhi Ye Bing Za Zhi 2018; 36:454-456. [PMID: 30248746 DOI: 10.3760/cma.j.issn.1001-9391.2018.06.016] [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] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Objective: To investigate the value of MRI in the early diagnosis of diagnosis of dysbaric osteonecrosis. Methods: Labor hygiene investigation and occupation health were examined on 52 high pressure operating personnel, were selected for the examination of both shoulders, hips and knees with X-ray and CT scan. Results: The cystic sign in dysbaric osteonecrosis as an important imaging feature, which perform in the MRI examination for T1W I sequence showed low or slightly low signal and T2W I sequence showed high signal, and X-ray and CT have a lower detection rate than MRI. The Kappa consistency test showed a high consistency with the two methods. At the same time MRI examination also can discover the bone marrow cavity necrosis early pathological change. Conclusion: MRI is an effective method for the diagnosis of early dysbaric osteonecrosis, which can improve the early diagnosis rate of dysbaric osteonecrosis.
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Affiliation(s)
- Y T Shen
- Yangpu Hospital, Tongji University, Shanhai 200090, China
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Lin YMJ, Hsin IL, Sun HS, Lin S, Lai YL, Chen HY, Chen TY, Chen YP, Shen YT, Wu HM. NTF3 Is a Novel Target Gene of the Transcription Factor POU3F2 and Is Required for Neuronal Differentiation. Mol Neurobiol 2018; 55:8403-8413. [PMID: 29549646 PMCID: PMC6153716 DOI: 10.1007/s12035-018-0995-y] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2017] [Accepted: 03/07/2018] [Indexed: 12/15/2022]
Abstract
POU-homeodomain transcription factor POU3F2 is a critical transcription factor that participates in neuronal differentiation. However, little is known about its downstream mediators. Here genome-wide analyses of a human neuronal differentiation cell model, NT2D1, suggested neurotrophin-3 (NTF3), a key mediator of neuronal development during the early neurogenic period, as a putative regulatory target of POU3F2. Western blot, cDNA microarray, and real-time quantitative PCR analyses showed that POU3F2 and NTF3 were upregulated during neuronal differentiation. Next-generation-sequence-based POU3F2 chromatin immunoprecipitation-sequencing and genome-wide in silico prediction demonstrated that POU3F2 binds to the NTF3 promoter during neuronal differentiation. Furthermore, unidirectional deletion or mutation of the binding site of POU3F2 in the NTF3 promoter decreased promoter-driven luciferase activity, indicating that POU3F2 is a positive regulator of NTF3 promoter activity. While NTF3 knockdown resulted in decreased viability and differentiation of NT2D1 cells, and POU3F2 knockdown downregulated NTF3 expression, recombinant NTF3 significantly rescued viable neuronal cells from NTF3- or POU3F2-knockdown cell cultures. Moreover, immunostaining showed colocalization of POU3F2 and NTF3 in developing mouse neurons. Thus, our data suggest that NTF3 is a novel target gene of POU3F2 and that the POU3F2/NTF3 pathway plays a role in the process of neuronal differentiation.
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Affiliation(s)
- Yi-Mei J Lin
- Institute of Biomedical sciences, National Chung Hsing University, Taichung City, Taiwan
| | - I-Lun Hsin
- Inflammation Research & Drug Development Center, Changhua Christian Hospital, No. 135 Nanxiao Street, Changhua, 500, Taiwan
| | - H Sunny Sun
- Institute of Molecular Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Shankung Lin
- Inflammation Research & Drug Development Center, Changhua Christian Hospital, No. 135 Nanxiao Street, Changhua, 500, Taiwan
| | - Yen-Ling Lai
- Inflammation Research & Drug Development Center, Changhua Christian Hospital, No. 135 Nanxiao Street, Changhua, 500, Taiwan
| | - Hsuan-Ying Chen
- Inflammation Research & Drug Development Center, Changhua Christian Hospital, No. 135 Nanxiao Street, Changhua, 500, Taiwan
| | - Ting-Yu Chen
- Inflammation Research & Drug Development Center, Changhua Christian Hospital, No. 135 Nanxiao Street, Changhua, 500, Taiwan
| | - Ya-Ping Chen
- Inflammation Research & Drug Development Center, Changhua Christian Hospital, No. 135 Nanxiao Street, Changhua, 500, Taiwan
| | - Yi-Ting Shen
- Institute of Biomedical sciences, National Chung Hsing University, Taichung City, Taiwan
| | - Hung-Ming Wu
- Inflammation Research & Drug Development Center, Changhua Christian Hospital, No. 135 Nanxiao Street, Changhua, 500, Taiwan.
- Graduate Institute of Acupuncture Science, China Medical University, Taichung, Taiwan.
- Department of Neurology, Changhua Christian Hospital, Changhua, Taiwan.
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Abstract
OBJECTIVES Outbreaks of shigellosis among men who have sex with men (MSM) have been reported since the late 1990s. HIV infection is an important risk factor. Since 2014, the global shigellosis epidemic has intensified. Whether chemsex (the use of crystal methamphetamine, γ-hydroxybutyrate or mephedrone to enhance sex) is a new risk factor has not been previously examined. METHODS We conducted a population-based, case-control study in Taiwan. Acute shigellosis cases diagnosed during the 2015 outbreak among MSM living with HIV were compared with those without shigellosis. CD4+ counts, plasma viral load (pVL), gonorrhoea, syphilis and amoebiasis records were obtained from the Notifiable Disease Surveillance System database. We invited cases/controls to provide information on illicit drug use and sexual behaviours, using a structured questionnaire. RESULTS Seventy-five shigellosis cases were compared with 225 controls. High pVL (>100 000 copies/mL; adjusted OR (aOR): 4.9, 95% CI 1.4 to 16.9), gonorrhoea (aOR: 29.4, 95% CI 2.3 to 340.2) and syphilis (aOR: 4.3, 95% CI 1.6 to 11.6) were independent risk factors of shigellosis. Twenty shigellosis cases and 59 controls completed the questionnaire. Oral-to-anal sex (aOR: 15.5, 95% CI 3.6 to 66.7), chemsex (aOR: 5.6, 95% CI 1.4 to 22.7) and poppers use (aOR: 10.9, 95% CI 1.9 to 64.2) within 12 months were independent behavioural risk factors of shigellosis. CONCLUSIONS Chemsex is a new risk factor for shigellosis among MSM living with HIV, as identified in the 2015-2016 outbreak. Additional risk factors include poppers use, sexual risk behaviours and high pVL. Further studies on chemsex among MSM, which is a rising public health concern, are urgently required.
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Affiliation(s)
- Hao-Hsin Wu
- Division of Infection Control and Biosafety, Centers for Disease Control, Taipei, Taiwan
| | - Yi-Ting Shen
- Office of Preventive Medicine, Centers for Disease Control, Taipei, Taiwan
| | - Chien-Shun Chiou
- Center for Diagnostics and Vaccine Development, Centers for Disease Control, Taipei, Taiwan
| | - Chi-Tai Fang
- Institute of Epidemiology and Preventive Medicine, College of Public Health, National Taiwan University, Taipei, Taiwan.,Division of Infectious Diseases, Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan
| | - Yi-Chun Lo
- Office of Deputy Director, Centers for Disease Control, Taipei, Taiwan
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Ge YJ, Cai XW, Lin H, Xu MY, Shen YT, Zhou D, Qian MJ, Deng J. [Base Activation of Peroxymonosulfate for the Degradation of Ciprofloxacin in Water]. Huan Jing Ke Xue 2017; 38:5116-5123. [PMID: 29964571 DOI: 10.13227/j.hjkx.201704232] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
The degradation of ciprofloxacin (CIP) in a base activated peroxymonosulfate (PMS) system was investigated. Results showed that a base activated PMS system can efficiently remove CIP. Singlet oxygen (1 O2) and superoxide anion radical (O2-·) were confirmed to be the major reactive oxygen species through radical quenching experiments. The NaOH concentration, PMS concentration, reactive temperature, and coexisting anions also affected CIP removal. Both NaOH and PMS concentration presented a dual effect, which was highly concentration dependent. An improvement in reactive temperature accelerated CIP degradation, and the calculated activation energy (Ea) was determined to be 5.09 kJ·mol-1 through the fitting of the Arrhenius equation. Different anions had different effects on CIP degradation. No obvious change in CIP concentration was observed when Cl-, SO42-, and NO3- were introduced. H2PO42- inhibited the degradation, but CO32- significantly promoted it. Ten oxidation products were identified through UPLC-MS/MS analysis, and the piperazine ring in the molecular structure of CIP was preferentially attacked by reactive oxygen species in the base activated PMS system.
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Affiliation(s)
- Yong-Jian Ge
- College of Civil Engineering and Architecture, Zhejiang University of Technology, Hangzhou 310014, China
| | - Xian-Wei Cai
- College of Civil Engineering and Architecture, Zhejiang University of Technology, Hangzhou 310014, China
| | - Han Lin
- College of Civil Engineering and Architecture, Zhejiang University of Technology, Hangzhou 310014, China
| | - Meng-Yuan Xu
- College of Civil Engineering and Architecture, Zhejiang University of Technology, Hangzhou 310014, China
| | - Yi-Ting Shen
- College of Civil Engineering and Architecture, Zhejiang University of Technology, Hangzhou 310014, China
| | - Dan Zhou
- College of Civil Engineering and Architecture, Zhejiang University of Technology, Hangzhou 310014, China
| | - Meng-Jie Qian
- College of Civil Engineering and Architecture, Zhejiang University of Technology, Hangzhou 310014, China
| | - Jing Deng
- College of Civil Engineering and Architecture, Zhejiang University of Technology, Hangzhou 310014, China
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12
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Chien T, Tseng TL, Wang JY, Shen YT, Lin TH, Shieh JC. Candida albicans DBF4 gene inducibly duplicated by the mini-Ura-blaster is involved in hypha-suppression. Mutat Res 2015; 779:78-85. [PMID: 26162773 DOI: 10.1016/j.mrfmmm.2015.06.013] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [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: 02/06/2015] [Revised: 06/15/2015] [Accepted: 06/26/2015] [Indexed: 06/04/2023]
Abstract
The opportunistic human fungal pathogen Candida albicans is a natural diploid that does not have a complete sexual cycle. The ability to switch between diverse cellular forms is important to its virulence. Here, we describe the characterization of the C. albicans DBF4 gene, a Saccharomyces cerevisiae homolog that encodes a regulatory subunit of Cdc7 kinase that is known to initiate DNA replication. We made a C. albicans strain, with one DBF4 allele deleted by the mini-Ura-blaster and the other controlled by a repressible promoter. We also found a third CaDBF4 copy that was later verified to be inducibly duplicated by targeted recombination with the min-Ura-blaster. Surprisingly, the strain deleted with the third CaDBF4 copy exhibited hyphal growth under repressed conditions. We conclude that the CaDBF4 gene is prone to being duplicated by the mini-Ura-blaster and that it suppresses hyphal growth in C. albicans.
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Affiliation(s)
- Ting Chien
- Department of Biomedical Sciences, Chung Shan Medical University, Taichung City, Taiwan, ROC
| | - Tzu-Ling Tseng
- Department of Biomedical Sciences, Chung Shan Medical University, Taichung City, Taiwan, ROC
| | - Jiun-Yuan Wang
- Department of Biomedical Sciences, Chung Shan Medical University, Taichung City, Taiwan, ROC
| | - Yi-Ting Shen
- Department of Biomedical Sciences, Chung Shan Medical University, Taichung City, Taiwan, ROC
| | - Ting-Hui Lin
- Department of Biomedical Sciences, Chung Shan Medical University, Taichung City, Taiwan, ROC
| | - Jia-Ching Shieh
- Department of Biomedical Sciences, Chung Shan Medical University, Taichung City, Taiwan, ROC; Department of Medical Research, Chung Shan Medical University Hospital, Taichung City, Taiwan, ROC.
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13
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Jheng HF, Tsai PJ, Chuang YL, Shen YT, Tai TA, Chen WC, Chou CK, Ho LC, Tang MJ, Lai KTA, Sung JM, Tsai YS. Albumin stimulates renal tubular inflammation through an HSP70-TLR4 axis in mice with early diabetic nephropathy. Dis Model Mech 2015; 8:1311-21. [PMID: 26398934 PMCID: PMC4610229 DOI: 10.1242/dmm.019398] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2014] [Accepted: 07/29/2015] [Indexed: 02/06/2023] Open
Abstract
Increased urinary albumin excretion is not simply an aftermath of glomerular injury, but is also involved in the progression of diabetic nephropathy (DN). Whereas Toll-like receptors (TLRs) are incriminated in the renal inflammation of DN, whether and how albumin is involved in the TLR-related renal inflammatory response remains to be clarified. Here, we showed that both TLR2 and TLR4, one of their putative endogenous ligands [heat shock protein 70 (HSP70)] and nuclear factor-κB promoter activity were markedly elevated in the kidneys of diabetic mice. A deficiency of TLR4 but not of TLR2 alleviated albuminuria, tubulointerstitial fibrosis and inflammation induced by diabetes. The protection against renal injury in diabetic Tlr4−/− mice was associated with reduced tubular injuries and preserved cubilin levels, rather than amelioration of glomerular lesions. In vitro studies revealed that albumin, a stronger inducer than high glucose (HG), induced the release of HSP70 from proximal tubular cells. HSP70 blockade ameliorated albumin-induced inflammatory mediators. HSP70 triggered the production of inflammatory mediators in a TLR4-dependent manner. Moreover, HSP70 inhibition in vivo ameliorated diabetes-induced albuminuria, inflammatory response and tubular injury. Finally, we found that individuals with DN had higher levels of TLR4 and HSP70 in the dilated tubules than non-diabetic controls. Thus, activation of the HSP70-TLR4 axis, stimulated at least in part by albumin, in the tubular cell is a newly identified mechanism associated with induction of tubulointerstitial inflammation and aggravation of pre-existing microalbuminuria in the progression of DN. Summary: Activation of the HSP70-TLR4 axis by albumin in the tubular cell induces tubular inflammation and injury.
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Affiliation(s)
- Huei-Fen Jheng
- Institute of Basic Medical Sciences, National Cheng Kung University, Tainan 701, Taiwan Institute of Clinical Medicine, National Cheng Kung University, Tainan 701, Taiwan
| | - Pei-Jane Tsai
- Institute of Basic Medical Sciences, National Cheng Kung University, Tainan 701, Taiwan Department of Medical Laboratory Science and Biotechnology, National Cheng Kung University, Tainan 701, Taiwan
| | - Yi-Lun Chuang
- Department of Physiology, National Cheng Kung University, Tainan 701, Taiwan
| | - Yi-Ting Shen
- Division of Nephrology, Department of Internal Medicine, National Cheng Kung University Hospital, Tainan 704, Taiwan
| | - Ting-An Tai
- Department of Physiology, National Cheng Kung University, Tainan 701, Taiwan
| | - Wen-Chung Chen
- Department of Pathology, National Cheng Kung University Hospital, Tainan 704, Taiwan
| | - Chuan-Kai Chou
- National Laboratory Animal Center, National Applied Research Laboratories, Taipei 115, Taiwan
| | - Li-Chun Ho
- Division of Nephrology, Department of Internal Medicine, E-DA Hospital/I-Shou University, Kaohsiung 824, Taiwan
| | - Ming-Jer Tang
- Department of Physiology, National Cheng Kung University, Tainan 701, Taiwan
| | | | - Junne-Ming Sung
- Division of Nephrology, Department of Internal Medicine, National Cheng Kung University Hospital, Tainan 704, Taiwan
| | - Yau-Sheng Tsai
- Institute of Basic Medical Sciences, National Cheng Kung University, Tainan 701, Taiwan Institute of Clinical Medicine, National Cheng Kung University, Tainan 701, Taiwan Research Center of Clinical Medicine, National Cheng Kung University Hospital, Tainan 704, Taiwan, Republic of China
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14
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Hu LW, Yen JH, Shen YT, Wu KY, Wu MJ. Luteolin modulates 6-hydroxydopamine-induced transcriptional changes of stress response pathways in PC12 cells. PLoS One 2014; 9:e97880. [PMID: 24846311 PMCID: PMC4028259 DOI: 10.1371/journal.pone.0097880] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2014] [Accepted: 04/25/2014] [Indexed: 01/08/2023] Open
Abstract
The neurotoxin 6-hydroxydopamine (6-OHDA), which causes transcriptional changes associated with oxidative and proteotoxic stress, has been widely used to generate an experimental model of Parkinson's disease. The food-derived compound luteolin has multi-target actions including antioxidant, anti-inflammatory and neurotrophic activities. The aim of this study is to investigate how luteolin affects 6-OHDA-mediated stress response pathways. The results showed that when PC12 cells were pre-treated with luteolin (20 µM) 30 min prior to 6-OHDA (100 µM) exposure, 6-OHDA-induced ROS overproduction, cytotoxicity, caspase-3 activation, and mRNA expression of BIM, TRB3 and GADD34 were significantly attenuated. Moreover, 6-OHDA-mediated cell cycle arrest and transcription of p53 target genes, p21, GADD45α and PUMA, were reduced by luteolin. Luteolin also significantly down-regulated 6-OHDA-mediated unfolded protein response (UPR), leading to decreases in phospho-eIF2α, ATF4, GRP78 and CHOP. In addition, luteolin attenuated 6-OHDA-induced Nrf2-mediated HO-1 and GCLC. Taken together, these results suggest that diminishing intracellular ROS formation and down-regulation of p53, UPR and Nrf2-ARE pathways may be involved in the neuroprotective effect of luteolin.
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Affiliation(s)
- Ling-Wei Hu
- Department of Biotechnology, Chia Nan University of Pharmacy and Science, Tainan, Taiwan
| | - Jui-Hung Yen
- Department of Molecular Biology and Human Genetics, Tzu Chi University, Hualien, Taiwan
| | - Yi-Ting Shen
- Department of Pharmacy, Chia Nan University of Pharmacy and Science, Tainan, Taiwan
| | - Kuan-Yi Wu
- Department of Biotechnology, Chia Nan University of Pharmacy and Science, Tainan, Taiwan
| | - Ming-Jiuan Wu
- Department of Biotechnology, Chia Nan University of Pharmacy and Science, Tainan, Taiwan
- * E-mail:
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15
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Li HB, Liao HY, Lin ST, Liu SK, Singh L, Singh MK, Soma AK, Wong HT, Wu YC, Zhao W, Asryan G, Chuang YC, Deniz M, Fang JM, Hsu CL, Huang TR, Kiran Kumar G, Lee SC, Li J, Li JM, Li YJ, Li YL, Lin CW, Lin FK, Liu YF, Ma H, Ruan XC, Shen YT, Singh V, Tang CJ, Tseng CH, Xu Y, Yang SW, Yu CX, Yue Q, Zeng Z, Zeyrek M, Zhou ZY. Limits on spin-independent couplings of WIMP dark matter with a p-type point-contact germanium detector. Phys Rev Lett 2013; 110:261301. [PMID: 23848861 DOI: 10.1103/physrevlett.110.261301] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2013] [Revised: 05/21/2013] [Indexed: 06/02/2023]
Abstract
We report new limits on a spin-independent weakly interacting massive particle (WIMP)-nucleon interaction cross section using 39.5 kg days of data taken with a p-type point-contact germanium detector of 840 g fiducial mass at the Kuo-Sheng Reactor Neutrino Laboratory. Crucial to this study is the understanding of the selection procedures and, in particular, the bulk-surface events differentiation at the sub-keV range. The signal-retaining and background-rejecting efficiencies were measured with calibration gamma sources and a novel n-type point-contact germanium detector. Part of the parameter space in the cross section versus WIMP-mass implied by various experiments is probed and excluded.
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Affiliation(s)
- H B Li
- Institute of Physics, Academia Sinica, Taipei 11529, Taiwan
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16
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Lin CY, Shen YT, Li YY, Huang YL, Lai JS. Trichosanthis Radix inhibits 3T3‐L1 adipogenesis. FASEB J 2012. [DOI: 10.1096/fasebj.26.1_supplement.969.2] [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)
| | | | | | - Yu-Ling Huang
- Agricultural Research InstituteCouncil of AgricultureExecutive YuanTaichungTaiwan
| | - Jui-Sheng Lai
- Agricultural Research InstituteCouncil of AgricultureExecutive YuanTaichungTaiwan
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17
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Tsai YJ, Pan H, Hung CM, Hou PT, Li YC, Lee YJ, Shen YT, Wu TT, Li C. The predominant protein arginine methyltransferase PRMT1 is critical for zebrafish convergence and extension during gastrulation. FEBS J 2011; 278:905-17. [PMID: 21214862 DOI: 10.1111/j.1742-4658.2011.08006.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Protein arginine methyltransferase (PRMT)1 is the predominant type I methyltransferase in mammals. In the present study, we used zebrafish (Danio rerio) as the model system to elucidate PRMT1 expression and function during embryogenesis. Zebrafish prmt1 transcripts were detected from the zygote period to the early larva stage. Knockdown of prmt1 by antisense morpholino oligo (AMO) resulted in delayed growth, shortened body-length, curled tails and cardiac edema. PRMT1 protein level, type I protein arginine methyltransferase activity, specific asymmetric protein arginine methylation and histone H4 R3 methylation all decreased in the AMO-injected morphants. The morphants showed defective convergence and extension and the abnormalities were more severe at the posterior than the anterior parts. Cell migration defects suggested by the phenotypes were not only observed in the morphant embryos, but also in a cellular prmt1 small-interfering RNA knockdown model. Rescue of the phenotypes by co-injection of wild-type but not catalytic defective prmt1 mRNA confirmed the specificity of the AMO and the requirement of methyltransferase activity in early development. The results obtained in the present study demonstrate a direct link of early development with protein arginine methylation catalyzed by PRMT1.
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Affiliation(s)
- Yun-Jung Tsai
- Department of Biomedical Sciences, Chung Shan Medical University, Taichung, Taiwan
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18
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Shen YT, Daoud MI, Lacefield JC. Computational models of distributed aberration in ultrasound breast imaging. IEEE Trans Ultrason Ferroelectr Freq Control 2010; 57:2627-2636. [PMID: 21156359 DOI: 10.1109/tuffc.2010.1737] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Two methods for simulation of ultrasound wavefront distortion are introduced and compared with aberration produced in simulations using digitized breast tissue specimens and a conventional multiple time-shift screen model. In the first method, aberrators are generated using a computational model of breast anatomy. In the second method, 10 to 12 irregularly shaped, strongly scattering inclusions are superimposed on the multiple-screen model to create a screen-inclusion model. Linear 2-D propagation of a 7.5-MHz planar, pulsed wavefront through each aberrator is computed using a first-order k-space method. The anatomical and screen-inclusion models reproduce two characteristics of arrival-time fluctuations observed in simulations using the digitized specimens that are not represented in simulations using the multiple-screen model: non-Gaussian first-order statistics and sharp changes in the rms arrival-time fluctuation as a function of propagation distance. The anatomical and screen-inclusion models both produce energy- level fluctuations similar to the digitized specimens, but the anatomical model more closely matches the pulse-shape distortion produced by the specimens. Both aberration models can readily be extended to 3-D, and the screen-inclusion model has the advantage of simplicity of implementation. Both models should enable more rigorous evaluation of adaptive focusing algorithms than is possible using conventional time-shift screen models.
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Affiliation(s)
- Yi-Ting Shen
- Department of Electrical and Computer Engineering, University of Western Ontario, London, Ontario, Canada
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19
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Tsai WC, Rao YK, Lin SS, Chou MY, Shen YT, Wu CH, Geethangili M, Yang CC, Tzeng YM. Methylantcinate A induces tumor specific growth inhibition in oral cancer cells via Bax-mediated mitochondrial apoptotic pathway. Bioorg Med Chem Lett 2010; 20:6145-8. [DOI: 10.1016/j.bmcl.2010.08.006] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2010] [Revised: 07/20/2010] [Accepted: 08/03/2010] [Indexed: 10/19/2022]
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20
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Chen L, Shen YT, Shannon RP. Diabetes and cardiovascular outcomes: finding the silver lining. Minerva Cardioangiol 2010; 58:253-267. [PMID: 20440254] [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: 05/29/2023]
Abstract
Type 2 diabetes mellitus and cardiovascular disease create a pernicious synergism that now threatens the public health in both developed and developing countries. As such, there has been a concerted therapeutic effort to mitigate the effects of hyperglycemia on adverse cardiovascular outcomes. Despite compelling epidemiological evidence linking diabetes to cardiovascular disease and mechanistic evidence linking hyperglycemia to cardiomyocyte and endothelial cell toxicity, clinical trials designed to examine the effects of tight glycemic control on CV outcomes have been disappointing. The apparent paradox requires a re-examination of the premise as well as consideration of new therapeutic approaches beyond tight glycemic control alone. In this review, we will review the evidence that links diabetes to adverse cardiovascular outcomes and will examine the mechanistic evidence whereby hyperglycemia causes cellular damage in experimental models. We will extrapolate from information gleaned from recent clinical trials and discuss a new therapeutic approach that embraces glycemic control, but with less collateral side effects and perhaps by mechanisms that are also cardio-protective.
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Affiliation(s)
- L Chen
- Cardiovascular Institute and the Department of Medicine, University of Pennsylvania, School of Medicine, Philadelphia, PA, USA
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21
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Shen YT, Kim TH, Gangopadhyay AK, Kelton KF. Icosahedral order, frustration, and the glass transition: evidence from time-dependent nucleation and supercooled liquid structure studies. Phys Rev Lett 2009; 102:057801. [PMID: 19257557 DOI: 10.1103/physrevlett.102.057801] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/23/2008] [Indexed: 05/27/2023]
Abstract
One explanation for the glass transition is a geometrical frustration owing to the development of non-space-filling short-range order (icosahedral, tetrahedral). However, experimental demonstrations of this are lacking. Here, the first quantitative measurements of the time-dependent nucleation rate in a Zr59Ti3Cu20Ni8Al10 bulk metallic glass are combined with the first measurements of the evolution of the supercooled liquid structure to near the glass transition temperature to provide strong support for an icosahedral-order-based frustration model for the glass transition in Zr-based glasses.
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Affiliation(s)
- Y T Shen
- Department of Physics, Washington University, St. Louis, Missouri 63130, USA
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22
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Abstract
Protein arginine methylation is a posttranslational modification involved in various cellular functions including cell signaling, protein subcellular localization and transcriptional regulation. We analyze the protein arginine methyltransferases (PRMTs) that catalyze the formation of methylarginines in porcine brain. We fractionated the brain extracts and determined the PRMT activities as well as the distribution of different PRMT proteins in subcellular fractions of porcine brain. The majority of the type I methyltransferase activities that catalyze the formation of asymmetric dimethylarginines was in the cytosolic S3 fraction. High specific activity of the methyltransferase was detected in the S4 fraction (high-salt stripping of the ultracentrifugation precipitant P3 fraction), indicating that part of the PRMT was peripherally associated with membrane and ribosomal fractions. The amount and distribution of PRMT1 are consistent with the catalytic activity. The elution patterns from gel filtration and anion exchange chromatography also indicate that the type I activity in S3 and S4 are mostly from PRMT1. Our results suggest that part of the type I arginine methyltransferases in brains, mainly PRMT1, are sequestered in an inactive form as they associated with membranes or large subcellular complexes. Our biochemical analyses confirmed the complex distribution of different PRMTs and implicate their regulation and catalytic activities in brain.
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Affiliation(s)
- Chien-Jen Hung
- Department of Biomedical Sciences, Chung Shan Medical University, Taichung, Taiwan, ROC
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23
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Tian F, Zhu J, Wei D, Shen YT. Magnetic field assisting DC electrodeposition: general methods for high-performance Ni nanowire array fabrication. J Phys Chem B 2007; 109:14852-4. [PMID: 16852880 DOI: 10.1021/jp051314h] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
One-dimensional magnetic nanowires are generally thought to show fine axial magnetism for their special high aspect ratio of the shape. However, the magnetic nanowire arrays fabricated by DC electrodeposition in template pores always show a low squareness in parallel to the nanowire direction. We developed two general and simple methods to improve the squareness of the as-fabricated Ni nanowire arrays parallel to the nanowire direction. The nanowires are found to be polycrystalline. The magnetism of the nanowire is also analyzed based on the microstructure.
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Affiliation(s)
- F Tian
- Electron Microscope Laboratory and Magnetic Physics Laboratory, School of Material Science and Engineering, Tsinghua University, Beijing 100084, China
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24
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Nikolaidis LA, Hentosz T, Doverspike A, Huerbin R, Stolarski C, Shen YT, Shannon RP. Mechanisms whereby rapid RV pacing causes LV dysfunction: perfusion-contraction matching and NO. Am J Physiol Heart Circ Physiol 2001; 281:H2270-81. [PMID: 11709392 DOI: 10.1152/ajpheart.2001.281.6.h2270] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Incessant tachycardia induces dilated cardiomyopathy in humans and experimental models; mechanisms are incompletely understood. We hypothesized that excessive chronotropic demands require compensatory contractility reductions to balance metabolic requirements. We studied 24 conscious dogs during rapid right ventricular (RV) pacing over 4 wk. We measured hemodynamic, coronary blood flow (CBF), myocardial O(2) consumption (MVO(2)) responses, myocardial nitric oxide (NO) production, and substrate utilization. Early pacing (6 h) resulted in decreased heart rate (HR)-adjusted coronary blood flow (CBF), MVO(2) (CBF/beat: 0.33 +/- 0.02 to 0.19 +/- 0.01 ml, P < 0.001, MVO(2)/beat: 0.031 +/- 0.002 to 0.016 +/- 0.001 ml O(2), P < 0.001), and contractility [left ventricular (LV) first derivative pressure (dP/dt)/LV end-diastolic diameter (EDD): 65 +/- 4 to 44 +/- 3 mmHg x s(-1) x mm(-1), P < 0.01], consistent with flow-metabolism-function coupling, which persisted over the first 72 h of pacing (CBF/beat: 0.15 +/- 0.01 ml, MVO(2)/beat: 0.013 +/- 0.001 ml O(2), P < 0.001). Thereafter, CBF per beat and MVO(2) per beat increased (CBF/beat: 0.25 +/- 0.01 ml, MVO(2)/beat: 0.021 +/- 0.001 ml O(2) at 28 days, P < 0.01 vs. 72 h). Contractility declined [(LV dP/dt)/LVEDD: 19 +/- 2 mmHg x s(-1) x mm(-1), P < 0.0001], signifying flow-function mismatch. Cardiac NO production, endothelial NO synthase expression, and fatty acid utilization decreased in late phase, whereas glycogen content and lactate uptake increased. Incessant tachycardia induces contractile, metabolic, and flow abnormalities reflecting flow-function matching early, but progresses to LV dysfunction late, despite restoration of flow and metabolism. The shift to flow-function mismatch is associated with impaired myocardial NO production.
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Affiliation(s)
- L A Nikolaidis
- Department of Medicine, Allegheny General Hospital, MCP-Hahnemann University School of Medicine, Pittsburgh, Pennsylvania 15212, USA
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25
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Shen YT, Pittman TJ, Buie PS, Bolduc DL, Kane SA, Koblan KS, Gould RJ, Lynch JJ. Functional role of alpha-calcitonin gene-related peptide in the regulation of the cardiovascular system. J Pharmacol Exp Ther 2001; 298:551-8. [PMID: 11454916] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/20/2023] Open
Abstract
It remains unknown whether the extent of vasoactive response to exogenous calcitonin gene-related peptide (CGRP) varies among different regional vascular beds. It is also unclear whether endogenous CGRP plays a functional role in regulating basal vascular activity. To address these two issues, experiments were conducted in 27 anesthetized rats instrumented with a carotid flow probe and catheters in a jugular vein, left ventricle (LV), and femoral artery, and in 6 conscious dogs, chronically instrumented with LV pressure gauge, aortic and atrial catheters, and ascending aortic, coronary, carotid, and renal flow probes. In both species, administration of human alpha-CGRP (0.1-0.5 microg/kg, i.v.) induced a dose-dependent peripheral vasodilation that was completely abolished by pretreatment with alpha-CGRP[8-37] (30 microg/kg/min, i.v.), a competitive antagonist of CGRP receptors. Regional blood flow measured by the radioactive microsphere technique in rats showed that the alpha-CGRP (0.3 microg/kg, i.v.)-induced increase in blood flow was greater (p < 0.05) in the heart (+53 +/- 16%) than in the brain (+14 +/- 6%). In the presence of beta-adrenergic receptor blockade with propranolol, however, the increases in blood flow in these two vascular beds were identical. In conscious dogs, alpha-CGRP (0.3 microg/kg, i.v.) produced similar increases in coronary (+24 +/- 6%), carotid (+26 +/- 3%), and renal (+26 +/- 6%) blood flow, which were different from the patterns induced by other vasodilators; at an equivalent level of reduction in mean arterial pressure and total peripheral resistance, alpha-CGRP increased coronary and carotid blood flow significantly less (p < 0.05) than adenosine or nitroprusside. Unlike alpha-CGRP, adenosine and nitroprusside, as expected, induced pronounced differential blood flow changes in these vascular beds. Neither systemic hemodynamics nor regional blood flow distribution was altered by the administration of a pharmacological blocking dose of alpha-CGRP[8-37] in the two species. Thus, we conclude that endogenous alpha-CGRP does not play an important role in cardiovascular regulation under normal, resting conditions, although exogenous alpha-CGRP induces a marked, comparable vasorelaxation in different regional vascular beds.
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Affiliation(s)
- Y T Shen
- Department of Pharmacology, Merck Research Laboratories, West Point, Pennsylvania 19486, USA.
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26
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Liu JL, Pliquett RU, Brewer E, Cornish KG, Shen YT, Zucker IH. Chronic endothelin-1 blockade reduces sympathetic nerve activity in rabbits with heart failure. Am J Physiol Regul Integr Comp Physiol 2001; 280:R1906-13. [PMID: 11353699 DOI: 10.1152/ajpregu.2001.280.6.r1906] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.7] [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: 01/22/2023]
Abstract
Endothelin-1 (ET-1) is elevated in chronic heart failure (CHF). In this study, we determined the effects of chronic ET-1 blockade on renal sympathetic nerve activity (RSNA) in conscious rabbits with pacing-induced CHF. Rabbits were chronically paced at 320–340 beats/min for 3–4 wk until clinical and hemodynamic signs of CHF were present. Resting RSNA and arterial baroreflex control of RSNA were determined. Responses were determined before and after the ET-1 antagonist L-754,142 (a combined ETA and ETB receptor antagonist, n = 5) was administered by osmotic minipump infusion (0.5 mg · kg−1 · h−1 for 48 h). In addition, five rabbits with CHF were treated with the specific ETA receptor antagonist BQ-123. Baseline RSNA (expressed as a percentage of the maximum nerve activity during sodium nitroprusside infusion) was significantly higher (58.3 ± 4.9 vs. 27.0 ± 1.0, P < 0.001), whereas baroreflex sensitivity was significantly lower in rabbits with CHF compared with control (3.09 ± 0.19 vs. 6.04 ± 0.73, P < 0.001). L-754,142 caused a time-dependent reduction in arterial pressure and RSNA in rabbits with CHF. In addition, BQ-123 caused a reduction in resting RSNA. For both compounds, RSNA returned to near control levels 24 h after removal of the minipump. These data suggest that ET-1 contributes to sympathoexcitation in the CHF state. Enhancement of arterial baroreflex sensitivity may further contribute to sympathoinhibition after ET-1 blockade in heart failure.
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Affiliation(s)
- J L Liu
- Department of Physiology and Biophysics, University of Nebraska College of Medicine, Omaha, Nebraska 68198-4575, USA
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Asai K, Kudej RK, Takagi G, Kudej AB, Natividad F, Shen YT, Vatner DE, Vatner SF. Paradoxically Enhanced Endothelin-B Receptor–Mediated Vasoconstriction in Conscious Old Monkeys. Circulation 2001; 103:2382-6. [PMID: 11352888 DOI: 10.1161/01.cir.103.19.2382] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Background
—We investigated the effects of aging on the responses to endothelin (ET) in conscious old (19.8±0.6 years) and young adult (6.8±0.3 years) monkeys and compared these results with those of other vasoconstrictors, eg, phenylephrine (PE) and angiotensin II (Ang II).
Methods and Results
—The monkeys (
Macaca fascicularis
) were chronically instrumented. Baseline total peripheral resistance (TPR) was not different between the 2 groups. As expected, TPR rose less (
P
<0.05) with PE (5 μg/kg) in old monkeys (34±3%) than in young monkeys (57±6%); TPR also rose less with Ang II. Surprisingly, TPR rose more (
P
<0.05) with endothelin-1 (ET-1, 25 ng · kg
−1
· min
−1
) in old monkeys (36±6%) than in young monkeys (10±2%). An ET
B
receptor agonist, sarafotoxin (S6c, 30 ng · kg
−1
· min
−1
) was administered in the presence of an ET
A
receptor antagonist, BQ-123 (1 mg/kg). Under these conditions, TPR increased more (
P
<0.05) in old monkeys (59±10%) than in young monkeys (31±4%). In the presence of nitric oxide synthase (NOS) inhibition with
N
W
-nitro-
l
-arginine methyl ester (60 mg/kg), vasoconstriction induced by S6c no longer differed with age, because it was enhanced in young monkeys (
P
<0.05) (68±9% versus 31±4%) but not in old monkeys (58±6% versus 59±10%). Thus, after NOS inhibition, vasoconstrictor responses to ET were no longer enhanced in old monkeys.
Conclusions
—Peripheral vasoconstriction (PE and Ang II) is reduced in old monkeys, as expected. Paradoxically, vasoconstriction induced by ET-1 was actually enhanced in old monkeys, which appears to be a result of impaired endothelium-dependent vasodilation, which with ET-1 should involve the ET
B
receptor.
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Affiliation(s)
- K Asai
- Cardiovascular Research Institute, University of Medicine, Dentistry of New Jersey, New Jersey Medical School, Newark, USA
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Gao H, Zhang ZH, Liu TL, Shen YT, Meng YL, Li XY. [The development of an automatic dialyser reuse device by microcomputer]. Zhongguo Yi Liao Qi Xie Za Zhi 2001; 25:151-150. [PMID: 12583285] [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: 05/24/2023]
Abstract
This article introduces the principles, composition and main functions of an automatic dialyser reuse device by microcomputer. It Ras more practical uses, better reliability, easier operations and greater effect than previous ones, and it's an ideal dialyser ruse device.
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Shen YT, Buie PS, Lynch JJ, Krause SM, Ma XL. Chronic therapy with an ET(A/B) receptor antagonist in conscious dogs during progression of congestive heart failure. Intracellular Ca(2+) regulation and nitric oxide mediated coronary relaxation. Cardiovasc Res 2000; 48:332-45. [PMID: 11054479 DOI: 10.1016/s0008-6363(00)00183-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/17/2022] Open
Abstract
BACKGROUND Although it is known that endothelin (ET-1) is elevated in heart failure (HF), it remains unclear if chronic ET(A/B) receptor antagonism affects the progression of HF, particularly by affecting coronary vasoactivity and left ventricular (LV) diastolic function. METHODS We examined the effects of an ET(A/B) receptor antagonist, L-753,037 (oral bid for 6 weeks, n=7), and vehicle (n=8) in conscious dogs with previously implanted aortic, coronary sinus and left atrial catheters, LV pressure gauge, aortic flow probe, LV dimension crystals and pacers. RESULTS Baseline hemodynamics were similar in the two groups. During the development of rapid pacing-induced HF, treatment with the ET(A/B) antagonist significantly reduced total peripheral resistance and increased cardiac output compared to vehicle. After 2 weeks of pacing, LV diastolic function (tau) was improved (P<0.05) in the ET(A/B) antagonist group (+6+/-2 ms) compared to the vehicle group (+12+/-2 ms). In addition, ET(A/B) antagonist treatment attenuated the increase in mean left atrial pressure and LV end-diastolic pressure that occurred during heart failure in vehicle-treated animals. However, LV systolic function (LV dP/dt, fractional shortening and Vcfc) neither at rest nor in response to dobutamine was altered by ET(A/B) antagonist treatment. Also, ET(A/B) antagonist treatment did not affect the progressive increases in LV dimension. After 6 weeks of pacing, maximal Ca(2+) transport in isolated cardiac sarcoplasmic reticulum (SR) was reduced (P<0.02) in the vehicle-treated compared to the ET(A/B) antagonist-treated dogs (1.34+/-0.09 vs. 1.60+/-0.06 micromol/mg/min, respectively). The improvement in SR function in the ET(A/B) antagonist-treated dogs was associated with a significant attenuation of the reduction in protein expression of SERCA2a and calsequestrin observed in the vehicle-treated dogs. Coronary arteries isolated from the dogs treated with the ET(A/B) antagonist exhibited enhanced (P<0.01) coronary endothelium-dependent relaxation compared to the vehicle group, while coronary responses to an NO donor were identical in the two groups. Plasma NO levels in the coronary sinus during the late stage of HF were higher (P<0.05) in the ET(A/B) antagonist group (40+/-2 microM) compared to the vehicle group (18+/-2 microM). CONCLUSIONS We conclude that in conscious dogs during the development of HF induced by rapid pacing, chronic inhibition of ET(A/B) receptors does not affect resting myocardial contractile function nor reserve, but reduces vascular resistance and improves LV diastolic function. After 6 weeks of pacing, the reduction in intracellular Ca(2+) regulation by the SR is also attenuated, and endothelium-dependent coronary relaxation is improved, which appears to be related to the preservation of coronary NO levels.
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Affiliation(s)
- Y T Shen
- Department of Pharmacology, Merck Research Laboratories, WP46-200, 19486, West Point, PA, USA.
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30
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Shen YT, Wiedmann RT, Lynch JJ, Gould RJ. Platelet glycoprotein IIb/IIIa receptor inhibitor preserves coronary flow reserve during progressive coronary arteriostenosis in swine. Arterioscler Thromb Vasc Biol 2000; 20:2309-15. [PMID: 11031220 DOI: 10.1161/01.atv.20.10.2309] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [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: 11/16/2022]
Abstract
Thrombosis resulting from blood platelet aggregation via glycoprotein (GP) IIb/IIIa receptor activation triggers the local release of vasoactive substances. Therefore, inhibition of these receptors could affect coronary vasoactive function during thrombotic coronary arteriostenosis. Twenty pigs were instrumented with an aortic catheter and with hydraulic occluders and flow probes on both the left anterior descending (LAD) and the left circumflex (LCx) coronary arteries. One of these 2 coronary arteries was repeatedly injured by external clamping for 15-second periods at 30-minute intervals while the pigs were given either a GP IIb/IIIa receptor inhibitor (L-739,758) (n=5), heparin (n=5), aspirin (n=3), or saline (n=7). There were no baseline differences between the 4 groups in mean arterial pressure, resting coronary blood flow (CBF), or reactive hyperemic response (RHR), which was induced by brief coronary artery occlusion and expressed as flow debt repayment. After multiple injuries, resting CBF had decreased by 95+/-2% (ie, nearly complete coronary artery occlusion) at 15+/-4 minutes in the control group, whereas in the heparin-, aspirin-, and GP IIb/IIIa inhibitor-treated groups, resting CBF had decreased by only 21+/-7% at 18+/-3 minutes, 15+/-3% at 18+/-5 minutes, and 15+/-7% at 21+/-4 minutes, respectively, suggesting that heparin, aspirin, and the GP IIb/IIIa inhibitor each prevented injury-induced coronary artery occlusion. After the initial injury, the RHR was progressively reduced in the control and heparin- and aspirin-treated groups but not in the GP IIb/IIIa inhibitor-treated group. At a comparable level of resting CBF ( approximately 15% below baseline), the RHR was reduced more in the control (-56+/-9%), heparin-treated (-49+/-9%), and aspirin-treated (-61+/-12) groups (P:<0.05) than in the GP IIb/IIIa inhibitor-treated group (-26+/-6%). When the resting CBF had decreased by approximately 35%, the RHR still was reduced significantly more (P<0.01) in the heparin-treated group (-64+/-9%) than in the GP IIb/IIIa inhibitor-treated group (-21+/-6%). In a separate group of control pigs (n=4) subjected to 2 injuries, coronary perfusion pressure distal to the injury site was reduced by 14+/-1 mm Hg from the arterial pressure, and the RHR was 20+/-6%. When the distal coronary perfusion pressure was reduced similarly (-14+/-1 mm Hg) in a separate group of GP IIb/IIIa inhibitor-treated pigs (n=4) by 2 injuries and the use of a hydraulic occluder, the RHR was 130+/-16% (P<0.01 versus control). Our data demonstrate for the first time that a platelet GP IIb/IIIa receptor inhibitor can preserve the distal coronary vasodilatory response during progressive coronary arteriostenosis.
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Affiliation(s)
- Y T Shen
- Department of Pharmacology, Merck Research Laboratories, West Point, PA, USA.
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31
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Kudej RK, Kim SJ, Shen YT, Jackson JB, Kudej AB, Yang GP, Bishop SP, Vatner SF. Nitric oxide, an important regulator of perfusion-contraction matching in conscious pigs. Am J Physiol Heart Circ Physiol 2000; 279:H451-6. [PMID: 10899086 DOI: 10.1152/ajpheart.2000.279.1.h451] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [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: 11/22/2022]
Abstract
We examined whether nitric oxide (NO) inhibition during moderate reduction in coronary blood flow (CBF) would affect perfusion-contraction matching. Coronary stenosis (CS) was induced in conscious pigs, which resulted in a stable 39 +/- 1% reduction in CBF for 1.5 h. Ischemic zone wall thickening (IZWT) decreased by an average of 56 +/- 2% during CS from 2.7 +/- 0.2 mm. After reperfusion, myocardial stunning was observed, but this recovered without evidence of necrosis. After recovery and subsequent administration of systemic NO synthase inhibition (N(omega)-nitro-L-arginine, 25 mg. kg(-1). day(-1) x 3 days), CS for 1.5 h reduced CBF similarly but decreased IZWT significantly more, P < 0.05, by 89 +/- 5%. Myocardial stunning, i.e., the decrease in IZWT at 12 h post-CS, was more severe (-65 +/- 5% vs. -21 +/- 3%), P < 0.05. Furthermore, CS during NO synthase inhibition resulted in multifocal subendocardial areas of necrosis in the area at risk. These data suggest that in the intact, conscious pig, NO inhibition prevents perfusion-contraction matching, resulting in intensification of post-ischemic stunning and development of subendocardial necrosis.
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Affiliation(s)
- R K Kudej
- Henry Hood Research Program, Weis Center for Research, Pennsylvania State University College of Medicine, Danville PA 17822, USA
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32
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Asai K, Kudej RK, Shen YT, Yang GP, Takagi G, Kudej AB, Geng YJ, Sato N, Nazareno JB, Vatner DE, Natividad F, Bishop SP, Vatner SF. Peripheral vascular endothelial dysfunction and apoptosis in old monkeys. Arterioscler Thromb Vasc Biol 2000; 20:1493-9. [PMID: 10845863 DOI: 10.1161/01.atv.20.6.1493] [Citation(s) in RCA: 137] [Impact Index Per Article: 5.7] [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] [Indexed: 01/13/2023]
Abstract
To determine the effects of aging on vasoactivity in a primate model (Macaca fascicularis), 13 young male monkeys (aged 7.1+/-0.4 years) and 9 old male monkeys (aged 19.8+/-0.6 years) were chronically instrumented for measurement of left ventricular and aortic pressures and cardiac output. Total cholesterol, triglyceride, and fasting blood sugar levels were not different between the 2 groups. There were no significant differences in baseline mean aortic pressure and total peripheral resistance (TPR) in the young monkeys versus the old monkeys. TPR fell less (P<0.05) with acetylcholine (1 microg/kg) in old monkeys (-25+/-1%) than in young monkeys (-34+/-2%), whereas decreases in TPR with sodium nitroprusside were similar in old and young monkeys. There was no evidence of atherosclerosis, but apoptosis of endothelial cells was enhanced (P<0.05) in the aortas and femoral arteries, but not in the media, of the old monkeys. There was a relationship (r=0.62, P=0.013) between the incidence of terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL)-positive endothelial cells and endothelial cell density in the femoral artery. The reduced endothelial cell density was also correlated (r=0.82, P<0.01) with depressed TPR responses to acetylcholine. Thus, vascular endothelial dysfunction was present in old monkeys without evidence of atherosclerosis, which may be due to endothelial apoptosis and reduced endothelial cell density.
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Affiliation(s)
- K Asai
- Weis Center for Research, Pennsylvania State University, College of Medicine, Danville 17822-2601, USA
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Abstract
OBJECTIVES Cardiovascular complications of cocaine use represent an important clinical problem, yet the mechanisms by which cocaine predisposes to myocardial ischemia are poorly understood. BACKGROUND The effects of cocaine on the coronary circulation have been studied extensively in experimental animal models, but have failed to recapitulate the clinical findings reported in humans who use cocaine. METHODS We studied 12 conscious, chronically instrumented dogs and 5 conscious, chronically instrumented baboons to determine whether there were important species differences in the response to cocaine. RESULTS Comparable doses of intravenous cocaine caused similar increases in left ventricular systolic, diastolic and mean arterial pressure in the two species. However, the peak coronary blood flow response in baboons (+8 +/- 3 from 47 +/- 6 ml/min) was less compared with dogs (+15 +/- 4 from 41 +/- 4 ml/min), while the coronary vascular resistance response was greater in baboons (+0.60 +/- 0.09 from 1.94 +/- 0.09 mm Hg/ml/mm) compared with dogs (+0.35 +/- 0.09 from 2.24 +/- 0.10 mm Hg/ml/min). Although myocardial oxygen consumption responses were similar between species, there was a significant difference (p < 0.05) in oxygen delivery between baboons (+164 +/- 47 from 705 +/- 59 ml of oxygen per minute) and dogs (+397 +/-51 from 656 +/- 33 ml of oxygen per minute) that was attributable to a significant (p < 0.05) increase in hemoglobin concentration in dogs (+2.1 +/- 0.5 g/dl) that was not observed in baboons. Consequently, cocaine caused a significant increase in myocardial oxygen extraction and decreased coronary sinus pH in baboons, but not dogs. CONCLUSIONS Cocaine caused greater coronary vasoconstriction and greater requirements for oxygen extraction in baboons compared with dogs.
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Affiliation(s)
- R P Shannon
- Department of Medicine, Allegheny General Hospital and the Cardiovascular & Pulmonary Research Institute, MCP Hahnemann University School of Medicine, Pittsburgh, Pennsylvania 15212, USA
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34
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Shen YT, Lynch JJ, Shannon RP, Wiedmann RT. A novel heart failure model induced by sequential coronary artery occlusions and tachycardiac stress in awake pigs. Am J Physiol 1999; 277:H388-98. [PMID: 10409219 DOI: 10.1152/ajpheart.1999.277.1.h388] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
A heart failure model was developed using conscious pigs subjected to serial myocardial infarctions followed by intermittent rapid ventricular pacing. Aortic and atrial catheters, left ventricular (LV) pressure gauge, LV dimension crystals, ascending aortic flow probe, pacing leads, and two coronary artery occluders were implanted in 15 pigs. The initial distal left circumflex coronary artery (LCX) occlusion produced a modest infarct, i.e., 18 +/- 3% of LV, and the second proximal LCX occlusion, performed 48 h later, enlarged the infarct to 33 +/- 2% of the LV with only modest changes in LV function. Thereafter, the pigs were subjected to ventricular pacing at 220 beats/min, which was maintained for 7 days and terminated for 3 days. This pacing cycle was repeated two more times and resulted in significantly impaired LV function and systemic hemodynamics. For example, after the second cycle of pacing, LV rate of pressure change (dP/dt, -41 +/- 4% from 2,778 +/- 112 mmHg/s), velocity of circumferential fiber shortening (V(cf): -53 +/- 6% from 1.1 +/- 0.1 s(-1)), and cardiac index (CI: -42 +/- 5% from 122 +/- 4 ml. min(-1). kg(-1)) were reduced significantly, whereas LV end-diastolic diameter (EDD: +34 +/- 6% from 39 +/- 2 mm), total peripheral resistance (TPR: +75 +/- 16% from 0.79 +/- 0.05 U), and mean left atrial pressure (LAP) (+21 +/- 1 mmHg from 5 +/- 1 mmHg) were increased significantly. Importantly, 3 wk after cessation of the final pacing cycle, LV dP/dt (-40 +/- 5%), V(cf) (-48 +/- 9%), and CI (-30 +/- 4%) remained depressed, whereas LV EDD (+39 +/- 5%), TPR (+43 +/- 9%), and LAP (+13 +/- 4 mmHg) were still increased. In contrast, hemodynamic impairment in six conscious pigs subjected to pacing only did not persist when pacing was terminated. Thus this model could provide a unique opportunity to study both the effects of preclinical therapeutic interventions and the mechanisms involved in the development of heart failure.
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Affiliation(s)
- Y T Shen
- Department of Pharmacology, Merck Research Laboratories, West Point, Pennsylvania 19486, USA.
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35
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Huang CH, Kim SJ, Ghaleh B, Kudej RK, Shen YT, Bishop SP, Vatner SF. An adenosine agonist and preconditioning shift the distribution of myocardial blood flow in conscious pigs. Am J Physiol 1999; 276:H368-75. [PMID: 9950835 DOI: 10.1152/ajpheart.1999.276.2.h368] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The goal of this study was to determine whether the cardioprotective effects of an A1-receptor agonist and ischemic preconditioning (IPC) involve a shift in the pre-coronary artery occlusion (CAO) spatial distribution of myocardial blood flow, which might shed light on the mechanism of IPC and explain its heterogeneous effects. Accordingly, 60 min of CAO followed by 72 h of coronary artery reperfusion (CAR) was examined in three groups of conscious pigs 10-14 days after instrumentation with aortic and left atrial catheters and coronary artery occluders. Myocardial infarct size, expressed as a fraction of the area at risk (AAR), was reduced significantly (P < 0.05) by infusion of the A1 agonist (27.1 +/- 6.6%) and to a greater extent (P < 0.05) by IPC (11.6 +/- 5.1%) compared with infarct size in vehicle-treated animals (55.1 +/- 2.9%). Transmural myocardial blood flow (radioactive microspheres) in the AAR shifted toward lower levels after infusion of the A1 agonist (1.27 +/- 0.19 vs. 0.74 +/- 0.10 ml. min-1. g-1) or IPC (1.27 +/- 0.11 vs. 0.96 +/- 0.09 ml. min-1. g-1) but not after infusion of the vehicle (1.20 +/- 0.10 vs. 1.23 +/- 0.09 ml. min-1. g-1). This study demonstrated that both pretreatment with an adenosine A1 agonist and also IPC altered the spatial distribution of pre-CAO myocardial blood flow, which might reflect a downregulation of metabolic state and thus play a role in the cardioprotective effects of IPC.
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Affiliation(s)
- C H Huang
- Cardiovascular and Pulmonary Research Institute, Allegheny University of the Health Sciences, Pittsburgh, Pennsylvania 15212, USA
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36
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Pan BS, Hannon JD, Wiedmann R, Potter JD, Kranias EG, Shen YT, Johnson RG, Housmans PR. Effects of isoproterenol on twitch contraction of wild type and phospholamban-deficient murine ventricular myocardium. J Mol Cell Cardiol 1999; 31:159-66. [PMID: 10072724 DOI: 10.1006/jmcc.1998.0854] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [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: 11/22/2022]
Abstract
Ablation of the gene for phospholamban (PLB), a transmembrane peptide regulator for the cardiac sarcoplasmic reticulum Ca2+ pump, in mice brings about a complete loss of the myocardial responses to beta-adrenergic agonists (e.g., Luo et al., Circ. Res. 1994; 75: 401). We have evaluated the functional significance of PLB-independent mechanisms in the myocardial responses to beta-adrenergic stimulation in isolated intact ventricular myocardium. We compared the effects of (-)-isoproterenol (ISO) on isometric twitch contraction of paced right ventricular muscle strips of wild type (WT) and PLB-deficient (PLBKO) mice. At 37 degrees C, frequent spontaneous contractions in both types of muscles required the inclusion of lidocaine, an antiarrhythmic, in the bathing medium. Thus the experiments were also performed at two lower temperatures, 30 degrees C and 25 degrees C, at which lidocaine was not needed. Under three conditions, in the absence of ISO, PLBKO ventricular muscles exhibited substantially shortened time to peak tension (TPT) and half relaxation time (TR1/2), compared with the WT muscles. In both WT and PLBKO muscles ISO increased the peak developed tension and decreased TPT and TR1/2 in a dose-dependent manner although the effects were generally smaller in PLBKO than in WT muscles. One micromolar ISO caused TPT and TR1/2 to decrease by 7.3+/-1.2% (mean+/-SEM) and 7.5+/-1.2% in PLBKO vs. 22.8+/-0.7% and 29.1+/-1.7% in WT at 37 degrees C; by 13.5+/-0.4% and 14.1+/-1.2% in PLBKO vs. 31.3+/-0.8%, and 44.8+/-1.3% in WT at 30 degrees C; by 15.0+/-2.3% and 21.1+/-4.9% in PLBKO vs. 25.8+/-1.9% and 54.0+/-1.9% in WT at 25 degrees C. These findings strongly suggest that PLB-independent mechanisms play a significant role in mediating the positive inotropic and lusitropic effects of beta-adrenergic agonists on ventricular myocardium.
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Affiliation(s)
- B S Pan
- Department of Pharmacology, Merck Res. Laboratories, West Point, PA 19486, USA
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37
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Shen YT, Wiedmann RT, Greenland BD, Lynch JJ, Grossman W. Combined effects of angiotensin converting enzyme inhibition and angiotensin II receptor antagonism in conscious pigs with congestive heart failure. Cardiovasc Res 1998; 39:413-22. [PMID: 9798526 DOI: 10.1016/s0008-6363(98)00117-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
OBJECTIVE The goal of this study was to determine if the hemodynamic effects of the combined administration of an angiotensin converting enzyme (ACE) inhibitor and angiotensin II type 1 (AT1) receptor antagonist are greater than those produced by either of these agents administered individually during heart failure. METHODS Ten farm pigs were chronically instrumented with aortic, left atrial and right atrial catheters, a left ventricular (LV) pressure gauge, LV dimension crystals, coronary occluders, an ascending aortic flow probe and pacing leads. Heart failure was induced by serial myocardial infarctions followed by repeated rapid ventricular pacing. RESULTS Heart failure was manifested by significant (p < 0.01) decreases in LV dP/dt (-38 +/- 5%, from 2943 +/- 107 mmHg/s) and cardiac output (-27 +/- 4%, from 4.1 +/- 0.2 l/min) and increases in left atrial pressure (+18 +/- 1 mmHg, from 4 +/- 1 mmHg) and total peripheral resistance (TPR)(+40 +/- 8%, from 23 +/- 2 mmHg/l/min). The effects of an ACE inhibitor (enalaprilat) and an AT1 receptor antagonist (L-158,809), administered in maximally effective doses, either individually or concomitantly, were examined on different days in conscious pigs with heart failure. There were no differences in any of the baseline hemodynamic measurements among the groups studied. Thirty minutes after administration, enalaprilat (4 mg/kg i.v.) increased (p < 0.05) cardiac output by 8 +/- 2% and reduced (p < 0.05) mean arterial pressure and TPR by 5 +/- 1 and 12 +/- 1%, respectively, while the changes in LV dP/dt (0 +/- 2%), LV fractional shortening (+4 +/- 3%) and heart rate (+1 +/- 1%) were not statistically significant. Similarly, L-158,809 (4 mg/kg, i.v.) increased cardiac output by 9 +/- 2% and reduced mean arterial pressure and TPR by 4 +/- 1 and 11 +/- 3%, respectively, while the changes in LV dP/dt (+3 +/- 3%), LV fractional shortening (+3 +/- 1%) and heart rate (0 +/- 1%) were not significant. However, enalaprilat (1 mg/kg, i.v.) and L-158,809 (1 mg/kg, i.v.), administered concomitantly, reduced TPR by 21 +/- 3%, an effect greater (p < 0.05) than when either of these agents was administered individually at a dose of 4 mg/kg, i.v. The changes in mean arterial pressure (-9 +/- 2%), cardiac output (+15 +/- 4%) and LV fractional shortening (+11 +/- 3%) also tended to be greater with concomitant administration. In addition, in a sequential dosing protocol, when L-158,809 (1 mg/kg, i.v.) was administered 30 min after enalaprilat (1 mg/kg, i.v.), TPR was reduced by 20 +/- 4% compared to only a 6 +/- 3% reduction (p < 0.05) when the enalaprilat was followed 30 min later by a second dose of enalaprilat (1 mg/kg, i.v.). The changes in mean arterial pressure and cardiac output for the combined treatment group also tended to be greater than those for the group given two sequential doses of enalaprilat. CONCLUSION In conscious pigs with heart failure, the combined vasodilatory effects of an ACE inhibitor and AT1 receptor antagonist are greater than those produced when only one of these agents is administered, suggesting that independent mechanisms of ACE inhibition and AT1 receptor antagonism could be partly responsible for the improved vascular dynamics during heart failure.
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Affiliation(s)
- Y T Shen
- Department of Pharmacology, Merck Research Laboratories, West Point, Pennsylvania 19486, USA
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38
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Kudej RK, Ghaleh B, Sato N, Shen YT, Bishop SP, Vatner SF. Ineffective perfusion-contraction matching in conscious, chronically instrumented pigs with an extended period of coronary stenosis. Circ Res 1998; 82:1199-205. [PMID: 9633919 DOI: 10.1161/01.res.82.11.1199] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.3] [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: 11/16/2022]
Abstract
Several models purported to represent hibernating myocardium involve a coronary stenosis (CS) to reduce blood flow (BF) and function without eliciting necrosis in anesthetized pigs. The goal of the present study was to determine whether sustained moderate reduction in coronary BF in conscious pigs induced hibernating myocardium, ie, perfusion-contraction matching with no necrosis. These experiments were conducted in conscious pigs chronically instrumented with a coronary artery BF probe and hydraulic occluder, left ventricular (LV) pressure gauge, and wall thickening (WT) crystals in the potentially ischemic and nonischemic zones. The hydraulic occluder was inflated to induce a stable 41+/-4% reduction in BF for 24 hours. Ischemic zone systolic WT fell initially with CS and then continued to decline during the period of CS even though blood flow did not change further, suggesting the induction of myocardial stunning. At 2 days after release of CS, WT was still depressed by 48+/-15%. Assessment of necrosis by histology or triphenyltetrazolium chloride showed 40+/-5% multifocal patchy necrosis interspersed with normal tissue involving the inner one third to one half of the ventricular wall. Regional myocardial BF (radioactive microsphere technique) was assessed by dividing the entire LV into an average of 488+/-59 pieces and examining the spatial distribution of BF within the area at risk (AAR). BF in the samples in the area of patchy necrosis was reduced (-66+/-4% from a baseline of 1.55+/-0.27 mL x min(-1) x g(-1)), whereas BF was maintained in samples in the AAR without necrosis (-2+/-7% from a baseline of 1.25+/-0.22 mL x min(-1) x g(-1)). These findings indicate that when hypoperfusion induced by CS in conscious pigs is sustained, the result is necrosis rather than hibernating myocardium. The remainder of the AAR, which lacked necrosis, might have been mistaken for hibernating myocardium had only histology been evaluated and BF not been measured and found to be at normal levels.
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Affiliation(s)
- R K Kudej
- Cardiovascular and Pulmonary Research Institute, Allegheny University of the Health Sciences, Pittsburgh, PA 15212, USA
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Shen YT, Woltmann RF, Appleby S, Prahalada S, Krause SM, Kivilghn SD, Johnson RG, Siegl PK, Lynch JJ. Lack of beneficial effects of growth hormone treatment in conscious dogs during development of heart failure. Am J Physiol 1998; 274:H456-66. [PMID: 9486248 DOI: 10.1152/ajpheart.1998.274.2.h456] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The effects of chronic treatment with growth hormone (porcine GH, 0.56 mg.kg-1.day-1 s.c.) were examined in dogs with heart failure induced by rapid ventricular pacing (240 beats/min) for 4 wk. Fourteen conscious dogs were studied 2-3 wk after surgical instrumentation with catheters in the descending aorta and left atrium, a pressure gauge in the left ventricle (LV), a flow probe around the ascending aorta, pacing leads on the ventricular free wall and left atrium, and ultrasonic crystals on the opposing anterior and posterior endomyocardium of the LV. GH treatment for 4 wk significantly increased both body weight and plasma insulin-like growth factor 1 (IGF-1) compared with vehicle-treated dogs (P < 0.01, +2.0 +/- 0.5 vs. +0.3 +/- 1.1 kg; 1,043 +/- 218 vs. 241 +/- 64 ng/ml, respectively). However, the changes in resting LV systolic (i.e., both isovolumic and ejection phases) and diastolic function (i.e., isovolumic relaxation time constant tau) and the systemic vascular resistance were similar for the GH- and vehicle-treated groups during the development of heart failure. LV contractile reserve, assessed with step infusion of isoproterenol or dobutamine challenge, was markedly attenuated after heart failure, but there were no differences between the GH- and vehicle-treated groups. During the progression of heart failure, the increases in plasma atrial natriuretic peptide correlated (P < 0.01) directly with left atrial pressure and inversely with LV circumferential fiber shortening. However, GH treatment did not substantially modify these relationships. In addition, renal function and myocardial ultrastructure at the advanced stage of heart failure also showed similar changes for the GH- and vehicle-treated groups. We conclude that in conscious dogs during the development of congestive heart failure produced by rapid ventricular pacing, GH at a dose that increases body weight and plasma IGF-1 levels does not affect LV performance or systemic vascular dynamics.
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Affiliation(s)
- Y T Shen
- Department of Pharmacology, Merck Research Laboratories, West Point, Pennsylvania 19486, USA
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von Harsdorf R, Edwards JG, Shen YT, Kudej RK, Dietz R, Leinwand LA, Nadal-Ginard B, Vatner SF. Identification of a cis-acting regulatory element conferring inducibility of the atrial natriuretic factor gene in acute pressure overload. J Clin Invest 1997; 100:1294-304. [PMID: 9276748 PMCID: PMC508307 DOI: 10.1172/jci119643] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.5] [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: 02/05/2023] Open
Abstract
To identify the cis-acting regulatory element(s) which control the induction of the atrial natriuretic factor (ANF) gene in acute pressure overload, DNA constructs consisting of promoter elements linked to a reporter gene were injected into the myocardium of dogs, which underwent aortic banding or were sham-operated. Expression of a reporter gene construct harboring the ANF promoter (-3400ANF) was induced 6-12-fold after 7 d of pressure overload. An internal deletion of 556 bp (nucleotide sequence -693 to -137) completely abrogated the inducibility of the ANF reporter gene construct. An activator protein-1 (AP1)-like site (-496 to -489) and a cAMP regulatory element (CRE) (-602 to -596) are located within the deleted sequence. Site-directed mutagenesis of the AP1-like site but not the CRE completely prevented the induction of this construct to acute pressure overload. Further, the AP1-like site was able to confer inducibility of a heterologous promoter (beta-myosin heavy chain) to higher values than controls. Gel mobility shift assay (GMSA) supershift analysis was performed using a radiolabeled probe of the ANF promoter (-506/-483) that included the AP1-like site (ATGAATCA) sequence, as well as a probe converted to contain an AP1 consensus sequence (ATGACTCA). GMSA analysis demonstrated that the ANF AP1-like element could bind both a constitutively expressed factor and the AP1 proteins, and conversion to a true AP1 site increased its affinity for AP1. However, 7 d after the onset of pressure overload, the AP1 proteins were present only at low levels, and the major complex formed by the ANF AP1-like probe was not supershifted by a jun antibody. Using a large animal model of pressure overload, we have demonstrated that a unique cis-acting element was primarily responsible for the overload induction of the ANF gene.
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Affiliation(s)
- R von Harsdorf
- Franz Volhard Klinik und Max-Delbrück-Centrum, Humboldt Universität zu Berlin, Berlin, Germany 13 122
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Rogers IT, Acker WR, Lodge KE, Holder DJ, Klein HJ, Lynch JJ, Shen YT. Effects of anesthesia and open-thorax surgery on coronary vascular reserve in swine. Lab Anim Sci 1997; 47:396-400. [PMID: 9306313] [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: 02/05/2023]
Abstract
The coronary reactive hyperemic response was examined in seven pigs under anesthetized and conscious conditions, (i.e., 5 days and 3 and 5 weeks after surgery). Tygon catheters were inserted in the descending aorta of five pigs; transonic flow probes and hydraulic occluders were placed on the left cranial descending and/or left circumflex coronary arteries. Two pigs underwent long-term implantation of similar instruments. The coronary reactive hyperemic response, expressed as repayment of flow deficit, was induced by brief complete coronary artery occlusion for 15 sec. Baseline mean arterial pressure, heart rate, and coronary blood flow were similar in the anesthetized and conscious pigs. There was also no significant difference in repayment of flow deficit between the anesthetized and conscious pigs 5 days after surgery. The repayment of flow deficit (709 +/- 144%) in conscious pigs 5 days after surgery tended to be greater, but was not statistically significant from that observed in the anesthetized pigs (510 +/- 79%). However, at 3 and 5 weeks after surgery, the reactive hyperemic flow and the repayment of flow deficit were numerically greater than those values observed in anesthetized pigs. The difference in reactive hyperemic flow between conscious and anesthetized pigs was statistically significant at week 3. The difference in repayment of flow deficit between conscious and anesthetized pigs was statistically significant at week 5. These results suggest that anesthesia, as well as recent surgery, attenuates coronary vascular reserve. The major factor in the attenuation of coronary reserve appears to be recent surgical manipulation, because repayment of flow deficit was still depressed in conscious pigs during the early phase of recovery from surgery.
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Affiliation(s)
- I T Rogers
- Laboratory Animal Resources, Merck Research Laboratories, West Point, PA 19486, USA
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Sato S, Sato N, Kudej RK, Uechi M, Asai K, Shen YT, Ishikawa Y, Vatner SF, Vatner DE. Beta-adrenergic receptor signalling in stunned myocardium of conscious pigs. J Mol Cell Cardiol 1997; 29:1387-400. [PMID: 9201624 DOI: 10.1006/jmcc.1997.0377] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [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: 02/04/2023]
Abstract
The primary goal of this study was to compare the effects of isoproterenol which stimulates beta-adrenergic receptors and forskolin, and NKH 477, a water soluble derivative of forskolin, which stimulate adenylyl cyclase in stunned myocardium of conscious pigs, previously instrumented for measurements of left ventricular pressure and dP/dt, arterial pressure, and wall thickening. Ten min of coronary artery occlusion induced transmural reductions in blood flow (radioactive microspheres) in subepicardium (-98 +/- 2%) and subendocardium (-99 +/- 1%). Wall thickening (piezoelectric crystals) fell from 2.50 +/- 0.26 mm to -0.26 +/- 0.26 mm and remained depressed at 1.37 +/- 0.19 mm after 20-30 min coronary artery reperfusion, reflecting myocardial stunning. At that time, isoproterenol (0.2 microgram/kg) increased wall thickening in stunned myocardium (+1.40 +/- 0.16 mm, P < 0.05) more than in control (+0.71 +/- 0.22 mm), while forskolin elicited the opposite effects. NKH 477 (30 micrograms/kg), which does not penetrate the blood-brain barrier, increased systolic wall thickening similarly before (+0.95 +/- 0.25 mm) and during (+1.01 +/- 0.24 mm) myocardial stunning. The reflex inotropic responses to inferior vena caval occlusion on wall thickening were diminished, P < 0.05, in the stunned myocardium (+0.53 +/- 0.05 mm) compared with control (+0.95 +/- 0.07 mm). beta-adrenergic receptor density, which was quantitated with 125I-cyanopindolol binding, was increased transmurally in stunned myocardium compared with non-ischemic myocardium (subepicardium: +23 +/- 5%, subendocardium: +34 +/- 13%, P < 0.05). Basal and forskolin-stimulated adenylyl cyclase activities were decreased slightly, but significantly, in the stunned subendocardium but not in the subepicardium, while isoproterenol stimulation of adenylyl cyclase activity showed no differences. In summary, paradoxical responses to beta-adrenergic receptor stimulation were observed in stunned myocardium, with pharmacological stimulation with isoproterenol evoking enhanced responses, and neural stimulation with inferior vena caval occlusion eliciting depressed responses. The diminished responses to forskolin in vivo, in stunned myocardium were out of proportion to the biochemical measurements, and may be attributed to neurally mediated cardiac effects of forskolin, since the responses to direct stimulation of adenylyl cyclase by NKH 477 were preserved.
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Affiliation(s)
- S Sato
- Department of Medicine, Harvard Medical School, Brigham & Women's Hospital, Boston, MA 02115, USA
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Sato N, Vatner SF, Shen YT, Kudej RK, Ghaleh-Marzban B, Uechi M, Asai K, Mirsky I, Patrick TA, Shannon RP, Vatner DE. Effects of cardiac denervation on development of heart failure and catecholamine desensitization. Circulation 1997; 95:2130-40. [PMID: 9133524 DOI: 10.1161/01.cir.95.8.2130] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
BACKGROUND Two signatures of heart failure are activation of the sympathetic nervous system and catecholamine desensitization. However, whether or not the elimination of cardiac nerves affects either the progression of heart failure or catecholamine desensitization is not clear. METHODS AND RESULTS We studied 8 dogs with selective ventricular denervation (VD) (surgical technique) and 10 intact dogs, chronically instrumented for measurement of left ventricular (LV) and arterial pressures, LV dP/dt, LV internal diameter, and wall thickness before and after heart failure was induced by rapid pacing (240 bpm) for 3 to 4 weeks. VD was confirmed by the absence of reflex effects induced by intracardiac veratrine and depletion of tissue norepinephrine and by supersensitive responses to norepinephrine. During the development of heart failure, LV end-systolic and end-diastolic stresses and heart rate increased, while myocardial contractility, as reflected by LV dP/dt and mean velocity of circumferential fiber shortening corrected for heart rate (Vcf(c)), decreased in both intact and VD dogs. However, the increases in LV end-diastolic stress and decreases in LV dP/dt as well as the relationship between LV systolic stress and Vcf(c) in heart failure were less (P<.05) in VD dogs. The responses of LV dP/dt and heart rate to both isoproterenol and norepinephrine in intact dogs were reduced in heart failure. The physiological desensitization to the inotropic effects of isoproterenol and norepinephrine was less in dogs with VD (P<.05), but chronotropic responses were similar because atrial innervation remained intact. Plasma norepinephrine levels were not different in VD dogs (592+/-79 pg/mL) compared with intact dogs (576+/-81 pg/mL) in heart failure. CONCLUSIONS Dogs with selective VD tolerated the development of heart failure better than intact dogs and demonstrated significantly less catecholamine desensitization. The latter indicates that intact ventricular innervation is required for physiological expression of catecholamine desensitization despite comparable elevation of plasma catecholamines during the development of heart failure.
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Affiliation(s)
- N Sato
- New England Regional Primate Research Center, Southborough, Mass 01772-9102, USA
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Shen YT, Wiedmann RT, Lynch JJ, Grossman W, Johnson RG. GH replacement fails to improve ventricular function in hypophysectomized rats with myocardial infarction. Am J Physiol 1996; 271:H1721-7. [PMID: 8945883 DOI: 10.1152/ajpheart.1996.271.5.h1721] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
To determine whether growth hormone (GH) replacement improves cardiac function, GH-deficient hypophysectomized rats with moderate myocardial infarction (MI) were studied after 3 wk of treatment with either recombinant rat GH (3.2 mg.kg-1.day-1 sc) or vehicle. The serum insulin-like growth factor I level in rats after GH treatment was approximately 10-fold greater than in vehicle-treated rats. GH replacement prevented a decrease in body weight at 1 wk (+5 +/- 6 vs. -26 +/- 4 g in vehicle group, P < 0.01) and increased body weight at 3 wk (+40 +/- 5 vs. -30 +/- 4 g in vehicle group, P < 0.01) after MI. Infarct size, expressed as a percentage of left ventricular (LV) perimeter, was similar for GH-treated (21 +/- 3%) and vehicle-treated (23 +/- 3%) rats. Basal LV systolic pressure, LV end-diastolic pressure, LV dP/dt, mean arterial pressure and heart rate, and the changes in these parameters in response to isoproterenol and norepinephrine were similar for these two groups. Although GH replacement tended to prevent depression in myocardial contractility during the recovery period after maximal stimulation either by the largest dose of isoproterenol (0.8 microgram/kg iv) or by acute volume loading, differences between the two groups were not statistically significant. In addition, to determine the effects of excess GH treatment in a severe state of cardiac dysfunction, nonhypophysectomized rats with larger infarcts (i.e., > 45% of the LV) were studied after 4 wk of treatment. There were no differences either in hemodynamic indexes or in infarct size between the GH- and vehicle-treated groups, whereas body weight had increased (P < 0.01) in the GH-treated group. Thus, although GH treatment effectively prevents the loss of body weight after MI, neither GH replacement nor excess GH treatment plays an important role in preserving cardiac function in rats with moderate or large MI.
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Affiliation(s)
- Y T Shen
- Department of Pharmacology and Clinical Research, Merck Research Laboratories, West Point, Pennsylvania 19486, USA
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Shen YT, Kudej RK, Bishop SP, Vatner SF. Inotropic reserve and histological appearance of hibernating myocardium in conscious pigs with ameroid-induced coronary stenosis. Basic Res Cardiol 1996; 91:479-85. [PMID: 8996633 DOI: 10.1007/bf00788729] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Inotropic reserve, demonstrated with administration of sympathomimetic amines, is characteristic of hibernating myocardium. The goal of this study was to determine whether inotropic reserve was present following chronic coronary artery constriction in the pig, which is one potential model of hibernating myocardium. The effects of isoproterenol were examined in five conscious pigs 21 +/- 2.1 days after ameroid implantation on the left circumflex coronary artery on measurements of left ventricular (LV) pressure, LV dP/dt, and regional wall thickening in the ameroid-dependent zone (posterior wall) and contralateral non-ischemic zone (anterior wall). Isoproterenol, 0.1 microgram/kg/min, increased LV dP/dt by 96 +/- 11%, heart rate by 43 +/- 13 beats/min, and normalized systolic wall thickening, slightly, but not significantly more in the ameroid-dependent zone (+1.57 +/- 0.31 mm) than in the contralateral non-ischemic zone (+1.04 +/- 0.31 mm), although the baseline wall thickening was reduced significantly in the ameroid-dependent zone. This occurred at a time when baseline myocardial blood flow was preserved and myocardial perfusion in the ameroid-dependent zone was derived in part from the native coronary circulation and also through collateral channels. Two weeks later histological evidence of lesions characteristic of hibernating myocardium, i.e., myofibrolysis and increased glycogen deposition, were observed. Thus, these histological changes and the confluence of chronically depressed regional function and residual inotropic reserve in the conscious pig with chronic ameroid-induced coronary constriction support this model for further study of hibernating myocardium.
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Affiliation(s)
- Y T Shen
- Harvard Medical School, New England Regional Primate Research Center, Southborough, MA 01772, USA
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46
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Abstract
BACKGROUND Myocardial blood flow distribution is known to be heterogeneous. It is also known that not all of the area at risk (AAR) infarcts with coronary artery occlusion (CAO) and coronary artery reperfusion (CAR). The goal of the present study was to determine whether the proportion of AAR that is salvaged or infarcted can be predicted by the pre-CAO level of myocardial blood flow, which varies considerably in individual samples as a result of natural heterogeneity. METHODS AND RESULTS The effects of 90-minute CAO followed by 5- to 7-day CAR were examined in six conscious baboons instrumented with aortic and left atrial catheters and coronary artery occluders. AAR was determined by dual perfusion. Myocardial blood flow was measured by radioactive microspheres before and after CAO and CAR. The AAR was cut into small pieces (0.21 +/- 0.01 g) and separated into two categories; salvaged (n = 252) or infarcted (n = 133). Analysis of myocardial blood flow distribution revealed two distinct populations (P < .01); infarcted tissues demonstrated higher pre-CAO myocardial blood flow than salvaged tissues. Importantly, 50% of the salvaged tissue samples were characterized by pre-CAO myocardial blood flows of < 0.90 mL.min-1.g-1 compared with 29% for infarcted samples, whereas 51% of infarcted samples were characterized by pre-CAO myocardial blood flows of > 1.12 mL.min-1.g-1 compared with 22% of salvaged samples. Endocardial analyses were qualitatively similar to transmural analyses. CONCLUSIONS This study suggests that heterogeneity of pre-CAO myocardial blood flows can predict the proportion of myocardium salvaged by CAR and can further explain the spatial heterogeneity of infarction that occurs after CAR, potentially independent of CAR injury.
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Affiliation(s)
- B Ghaleh
- Department of Medicine, Harvard Medical School, Brigham & Women's Hospital, Boston, Mass, USA
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Iwase M, Ishikawa Y, Shen YT, Shannon RP, Sato N, Ganguly PK, Eki T, Vatner DF, Vatner SF. Neurally mediated cardiac effects of forskolin in conscious dogs. Am J Physiol 1996; 271:H1473-82. [PMID: 8897942 DOI: 10.1152/ajpheart.1996.271.4.h1473] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Because major cardiovascular disease states are characterized by defects in adenylyl cyclase regulation, it becomes important to understand the mechanisms by which adenylyl cyclase activators affect inotropy and chronotropy in intact conscious animals. Accordingly, we examined the inotropic and chronotropic responses to forskolin in 11 normal conscious, chronically instrumented dogs and 3 dogs with ventricular denervation (VD). Left ventricular first derivative of pressure (LV dP/dt) increased by 96 +/- 7%, P < 0.05, in response to forskolin (50 nmol.kg-1.min-1) in normal dogs and by significantly less, 52 +/- 14%, in VD dogs. Circulating norepinephrine (NE) levels increased similarly in both groups (from 226 +/- 18 to 389 +/- 33 pg/ml in normal dogs, from 177 +/- 23 to 329 +/- 71 pg/ml in VD dogs). In the presence of ganglionic blockade, the increase in LV dP/dt in response to forskolin was reduced (+62 +/- 4%) in normal dogs but was unchanged in VD dogs (+52 +/- 12%). Ganglionic blockade abolished the increase in circulating NE levels in both groups. Increases in heart rate in the presence of ganglionic blockade (+54 +/- 6 beats/min) were less than in the presence of atropine alone (+92 +/- 10 beats/min). Notably, the LV dP/dt and heart rate responses to forskolin were further attenuated by beta-adrenergic receptor blockade in the presence and absence of ganglionic blockade. Morphine also attenuated the increases in both LV dP/dt and plasma NE in response to forskolin. Increases in LV dP/dt in response to NKH-477 (30 micrograms/kg), a water-soluble forskolin derivative, were similar before and after ganglionic blockade (+63 +/- 8 and +51 +/- 10%, respectively). However, in vitro experiments in LV sarcolemmal membrane preparations demonstrated that stimulation of adenylyl cyclase by forskolin and NKH-477 was not affected by beta-adrenergic receptor blockade. These results indicate that in conscious dogs, inotropic and chronotropic effects of forskolin are not only due to direct activation of adenylyl cyclase, but the effects also are mediated by neural mechanisms and potentiated by the prevailing level of sympathetic tone.
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Affiliation(s)
- M Iwase
- Department of Medicine, Harvard Medical School, Brigham and Women's Hospital, Boston 02115, USA
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Shen YT, Cervoni P, Claus T, Vatner SF. Differences in beta 3-adrenergic receptor cardiovascular regulation in conscious primates, rats and dogs. J Pharmacol Exp Ther 1996; 278:1435-43. [PMID: 8819531] [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
The goal of our study was to compare the effects of two beta 3-adrenergic receptor agonists, i.e., BRL37344 (BRL) and CL316243 (CL), in conscious dogs, rats and nonhuman primates, instrumented with aortic and atrial catheters, ascending aortic flow probes and left ventricular (LV) pressure gauges. In conscious dogs, CL, 10 micrograms/kg, i.v., reduced, P < .05, mean arterial pressure by 8 +/- 4% and total peripheral resistance by 51 +/- 4% and increased, P < .05, LV dP/dt by 79 +/- 10% and heart rate by 88 +/- 8%. These responses were similar to those induced by BRL, 8.3 micrograms/kg, i.v. After autonomic blockade (beta 1/beta 2-adrenergic, cholinergic and ganglionic), CL still reduced total peripheral resistance by 49 +/- 4%, and increased LV dP/dt by 21 +/- 4%, without an effect on heart rate. In conscious rats, 10 times the dose of CL 100 micrograms/kg, i.v., reduced, P < .05, total peripheral resistance by 18 +/- 4%, without major effects on LV dP/dt and heart rate. BRL, 83 micrograms/kg i.v., reduced total peripheral resistance similarly by 31 +/- 3%, and increased heart rate (25 +/- 3%) and LV dP/dt (27 +/- 5%) more, P < .05. In conscious monkeys and baboons, CL, 100 micrograms/kg, i.v., did not induce significant effects, whereas BRL, 83 micrograms/kg, i.v., increased heart rate (36 +/- 6%), LV dP/dt (85 +/- 9%) and decreased total peripheral resistance (30 +/- 2%). After beta 1/beta 2-adrenergic receptor blockade in rats and primates, there were almost no differences between BRL and CL, i.e., in primates there were almost no significant cardiovascular effects with either compound. Both CL and BRL increased circulating free fatty acids in the dog, but not in the baboon. Thus, CL appears to be a more specific beta 3-adrenergic receptor agonist than BRL. More importantly, beta 3-adrenergic receptor stimulation was most profound in dogs, where even a direct effect on LV contractility was identified, was diminished but still significant in rats, and essentially absent in primates.
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Affiliation(s)
- Y T Shen
- Department of Medicine, Harvard Medical School, Brigham & Women's Hospital Boston, Massachusetts, USA
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Cui Y, Shen YT, Kalthof B, Iwase M, Sato N, Uechi M, Vatner SF, Vatner DE. Identification and functional role of beta-adrenergic receptor subtypes in primate and rodent: in vivo versus isolated myocytes. J Mol Cell Cardiol 1996; 28:1307-17. [PMID: 8782072 DOI: 10.1006/jmcc.1996.0121] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
We determined the relationship between the beta 1- and beta 2-adrenergic receptor subtypes in isolated myocytes and their physiological responsiveness in chronically instrumented conscious baboons and rats. In conscious baboons, isoproterenol (ISO) (0.02 microgram/kg) increased left ventricular (LV) dP/dt by 89 +/- 6.7% from 2898 +/- 370 mmHg/s and only by 13 +/- 3.3% from 2491 +/- 146 mmHg/s after beta 1-adrenergic receptor blockade, indicating that the predominant physiological response was mediated by beta 1-adrenergic receptors. Decreases in mean arterial pressure (-11 +/- 0.5 mmHg v -16 +/- 4.6 mmHg) and coronary vascular resistance (-3.1 +/- 0.4 v -3.6 +/- 0.4 mmHg/ml/min) induced by ISO were not different before and after beta 1-blockade, indicating that beta 2-adrenergic receptors were not blocked. In conscious rats, ISO (0.4 microgram/kg) increased LV dP/dt by 50 +/- 4.9% from 13252 +/- 2002 mmHg/s and only by 10 +/- 3.9% from 10793 +/- 1364 mmHg/s after beta 1-adrenergic receptor blockade: whereas decreases in mean arterial pressure induced by ISO were not different before and after beta 1-blockade (-19 +/- 2.4 mmHg v -16 +/- 2.2 mmHg), i.e. very consistent with the physiological responses in baboons. In vitro studies of isolated myocytes, using radioligand binding with 125I-cyanopindolol (125I-cyp) and the subtype beta 1-selective antagonist betaxolol and the beta 2-selective antagonist ICI 118551 indicated that the beta 1/beta 2 ratio of rat myocytes was 92/8: whereas baboon myocytes were more equally distributed (59/41). Thus, in both species the preponderance of effects of ISO on ventricular function was beta 1-adrenergic receptor mediated, which is consistent with the beta 1/beta 2 ratio in rat myocytes but not in baboon myocytes, where a significant fraction of beta 2-adrenergic receptors does not appear to exert an effect on conctractility in vivo.
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MESH Headings
- Adrenergic beta-Antagonists/pharmacology
- Animals
- Betaxolol/pharmacology
- Blood Pressure/drug effects
- Cells, Cultured
- Coronary Vessels/drug effects
- Coronary Vessels/physiology
- Heart/drug effects
- Heart/physiology
- Heart Rate/drug effects
- In Vitro Techniques
- Isoproterenol/pharmacology
- Kinetics
- Male
- Myocardium/metabolism
- Papio
- Pindolol/analogs & derivatives
- Pindolol/metabolism
- Propanolamines/pharmacology
- Rats
- Rats, Sprague-Dawley
- Receptors, Adrenergic, beta-1/drug effects
- Receptors, Adrenergic, beta-1/physiology
- Receptors, Adrenergic, beta-2/drug effects
- Receptors, Adrenergic, beta-2/physiology
- Vascular Resistance/drug effects
- Ventricular Function, Left/drug effects
- Ventricular Function, Right/drug effects
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Affiliation(s)
- Y Cui
- Department of Medicine, Harvard Medical School, Brigham & Women's Hospital, Massachusetts General Hospital, Boston 02114, USA
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50
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Abstract
To determine whether the extent of myocardial infarction differs in conscious baboons and pigs, both devoid of performed collaterals, the effects of 40 and 90 min of coronary artery (CA) occlusion (O) both followed by 4-7 days of CA reperfusion (R) were examined in both species. CAO reduced subendocardial and subepicardial blood flows similarly, almost to zero, in baboons and pigs for the entire CAO period. At 24 h of CAR, subendocardial blood flow had almost returned to pre-CAO control levels in baboons but remained significantly depressed in pigs. The major difference in hemodynamics during CAO and CAR was in left ventricular end-diastolic pressure, which rose by 6 +/- 1 mmHg in pigs over the initial 24-h reperfusion period but did not change significantly in baboons. These data on recovery of subendocardial blood flow and left ventricular end-diastolic pressure suggest larger infarcts in pigs than in baboons. Indeed, infarct size expressed as a function of area at risk (IF/AAR) was significantly greater (P < 0.05) in pigs (53 +/- 4.9%) than in baboons (17 +/- 2.9%) with 90 min of CAO and 4-7 days of CAR. With 40 min of CAO and 4-7 days of CAR, IF/AAR was 46 +/- 3.6% in pigs, whereas in baboons the IF/AAR was minimal, i.e., 2 +/- 0.6%. Thus pigs and baboons were characterized by minimal coronary collateral circulation, but infarct size was significantly less in conscious baboons than in conscious pigs. Potentially, these differences could be explained, in part, by natural protective mechanisms and/or less reperfusion injury in primates. These results in primates may also help explain the salutary effects of CAR in patients at intervals longer than have been demonstrated to be beneficial in other experimental animals.
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Affiliation(s)
- Y T Shen
- Department of Medicine, Harvard Medical School, Boston, Massachusetts, USA
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