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Xu W, Yi SH, Feng R, Wang X, Jin J, Mi JQ, Ding KY, Yang W, Niu T, Wang SY, Zhou KS, Peng HL, Huang L, Liu LH, Ma J, Luo J, Su LP, Bai O, Liu L, Li F, He PC, Zeng Y, Gao D, Jiang M, Wang JS, Yao HX, Qiu LG, Li JY. [Current status of diagnosis and treatment of chronic lymphocytic leukemia in China: A national multicenter survey research]. Zhonghua Xue Ye Xue Za Zhi 2023; 44:380-387. [PMID: 37550187 PMCID: PMC10440613 DOI: 10.3760/cma.j.issn.0253-2727.2023.05.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Received: 06/06/2022] [Indexed: 08/09/2023]
Abstract
Objective: To understand the current status of diagnosis and treatment of chronic lymphocytic leukemia (CLL) /small lymphocytic lymphoma (SLL) among hematologists, oncologists, and lymphoma physicians from hospitals of different levels in China. Methods: This multicenter questionnaire survey was conducted from March 2021 to July 2021 and included 1,000 eligible physicians. A combination of face-to-face interviews and online questionnaire surveys was used. A standardized questionnaire regarding the composition of patients treated for CLL/SLL, disease diagnosis and prognosis evaluation, concomitant diseases, organ function evaluation, treatment selection, and Bruton tyrosine kinase (BTK) inhibitor was used. Results: ①The interviewed physicians stated that the proportion of male patients treated for CLL/SLL is higher than that of females, and the age is mainly concentrated in 61-70 years old. ②Most of the interviewed physicians conducted tests, such as bone marrow biopsies and immunohistochemistry, for patient diagnosis, in addition to the blood test. ③Only 13.7% of the interviewed physicians fully grasped the initial treatment indications recommended by the existing guidelines. ④In terms of cognition of high-risk prognostic factors, physicians' knowledge of unmutated immunoglobulin heavy-chain variable and 11q- is far inferior to that of TP53 mutation and complex karyotype, which are two high-risk prognostic factors, and only 17.1% of the interviewed physicians fully mastered CLL International Prognostic Index scoring system. ⑤Among the first-line treatment strategy, BTK inhibitors are used for different types of patients, and physicians have formed a certain understanding that BTK inhibitors should be preferentially used in patients with high-risk factors and elderly patients, but the actual use of BTK inhibitors in different types of patients is not high (31.6%-46.0%). ⑥BTK inhibitors at a reduced dose in actual clinical treatment were used by 69.0% of the physicians, and 66.8% of the physicians had interrupted the BTK inhibitor for >12 days in actual clinical treatment. The use of BTK inhibitors is reduced or interrupted mainly because of adverse reactions, such as atrial fibrillation, severe bone marrow suppression, hemorrhage, and pulmonary infection, as well as patients' payment capacity and effective disease progression control. ⑦Some differences were found in the perceptions and behaviors of hematologists and oncologists regarding the prognostic assessment of CLL/SLL, the choice of treatment options, the clinical use of BTK inhibitors, etc. Conclusion: At present, a gap remains between the diagnosis and treatment of CLL/SLL among Chinese physicians compared with the recommendations in the guidelines regarding the diagnostic criteria, treatment indications, prognosis assessment, accompanying disease assessment, treatment strategy selection, and rational BTK inhibitor use, especially the proportion of dose reduction or BTK inhibitor discontinuation due to high adverse events.
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Affiliation(s)
- W Xu
- Department of Hematology, the First Affiliated Hospital of Nanjing Medical University, Jiangsu Province Hospital, Nanjing 210029, China
| | - S H Yi
- State Key Laboratory of Experimental Hematology, National Clinical Research Center for Blood Diseases, Haihe Laboratory of Cell Ecosystem, Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin 300020, China
| | - R Feng
- Nanfang Hospital, Southern Medical University, Guangzhou 510515, China
| | - X Wang
- Shandong Provincial Hospital, Jinan 250021, China
| | - J Jin
- The First Affiliated Hospital of Medical College of Zhejiang University, Hangzhou 310003, China
| | - J Q Mi
- Ruijin Hospital Affiliated to Medical College of Shanghai Jiaotong University, Shanghai 200025, China
| | - K Y Ding
- Anhui Province Cancer Hospital, Hefei 230031, China
| | - W Yang
- Shengjing Hospital Affiliated to China Medical University, Shenyang 117004, China
| | - T Niu
- West China Hospital of Sichuan University, Chengdu 610044, China
| | - S Y Wang
- Union Hospital Affiliated to Fujian Medical University, Fuzhou 350001, China
| | - K S Zhou
- Henan Cancer Hospital (Affiliated Cancer Hospital of Zhengzhou University), Zhengzhou 450003, China
| | - H L Peng
- Xiangya Second Hospital of Central South University, Changsha 410008, China
| | - L Huang
- Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - L H Liu
- The Fourth Hospital of Hebei Medical University (Hebei Tumor Hospital), Shijiazhuang 050011, China
| | - J Ma
- Harbin Institute of hematological oncology, Harbin 150001, China
| | - J Luo
- The First Affiliated Hospital of Guangxi Medical University, Nanchang 530021, China
| | - L P Su
- Shanxi Cancer Hospital, Taiyuan 030013, China
| | - O Bai
- The first hospital of Jilin University, Changchun 130061, China
| | - L Liu
- The First Affiliated Hospital of Chongqing Medical University, Chongqing 400042, China
| | - F Li
- The First Affiliated Hospital of Nanchang University, Nanchang 330006, China
| | - P C He
- The First Affiliated Hospital of Xi' an Jiaotong University, Xi' an 710061, China
| | - Y Zeng
- The First Affiliated Hospital of Kunming Medical University, Kunming 650032, China
| | - D Gao
- Affiliated Hospital of Inner Mongolia Medical University, Hohhot 750306, China
| | - M Jiang
- The First Affiliated Hospital of Xinjiang Medical University, Urumqi 830011, China
| | - J S Wang
- Affiliated hospital of Guizhou Medical University, Guiyang 550004, China
| | - H X Yao
- Hainan Provincial People's Hospital, Haikou 570311, China
| | - L G Qiu
- State Key Laboratory of Experimental Hematology, National Clinical Research Center for Blood Diseases, Haihe Laboratory of Cell Ecosystem, Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin 300020, China
| | - J Y Li
- Department of Hematology, the First Affiliated Hospital of Nanjing Medical University, Jiangsu Province Hospital, Nanjing 210029, China
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2
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Liu JN, Dolikun M, Štambuk J, Trbojević-Akmačić I, Zhang J, Wang H, Zheng DQ, Zhang XY, Peng HL, Zhao ZY, Liu D, Sun Y, Sun Q, Li QH, Zhang JX, Sun M, Cao WJ, Momčilović A, Razdorov G, Wu LJ, Russell A, Wang YX, Song MS, Lauc G, Wang W. The association between subclass-specific IgG Fc N-glycosylation profiles and hypertension in the Uygur, Kazak, Kirgiz, and Tajik populations. J Hum Hypertens 2018; 32:555-563. [PMID: 29867134 DOI: 10.1038/s41371-018-0071-0] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2017] [Revised: 03/15/2018] [Accepted: 04/06/2018] [Indexed: 01/01/2023]
Abstract
Hypertension results from the interaction of genetic and acquired factors. IgG occurs in the form of different subclasses, of which the effector functions show significant variation. The detailed differences between the glycosylation profiles of the individual IgG subclasses may be lost in a profiling method for total IgG N-glycosylation. In this study, subclass-specific IgG Fc glycosylation profile was investigated in the four northwestern Chinese minority populations, namely, Uygur (UIG), Kazak (KZK), Kirgiz (KGZ), and Tajik (TJK), composed of 274 hypertensive patients and 356 healthy controls. The results showed that ten directly measured IgG N-glycan traits (i.e., IgG1G0F, IgG2G0F, IgG2G1FN, IgG2G1FS, IgG2G2S, IgG4G0F, IgG4G1FS, IgG4G1S, IgG4G2FS, and IgG4G2N) representing galactosylation and sialylation are significantly associated with hypertension, with IgG4 consistently showing weaker associations of its sialylation, across the four ethnic groups. We observed a modest improvement on the AUC of ROC curve when the IgG Fc N-glycan traits are added into the glycan-based model (difference between AUCs, 0.044, 95% CI: 0.016-0.072, P = 0.002). The AUC of the diagnostic model indicated that the subclass-specific IgG Fc N-glycan profiles provide more information reinforcing current models utilizing age, gender, BMI, and ethnicity, and demonstrate the potential of subclass-specific IgG Fc N-glycosylation profiles to serve as a biomarker for hypertension. Further research is however required to determine the additive value of subclass-specific IgG Fc N-glycosylation on top of biomarkers, which are currently used.
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Affiliation(s)
- J N Liu
- Beijing Key Laboratory of Clinical Epidemiology, School of Public Health, Capital Medical University, Beijing, China
| | - M Dolikun
- College of the Life Sciences and Technology, Xinjiang University, Urumqi, China
| | - J Štambuk
- Genos Glycoscience Research Laboratory, Zagreb, Croatia
| | | | - J Zhang
- Beijing Key Laboratory of Clinical Epidemiology, School of Public Health, Capital Medical University, Beijing, China
| | - H Wang
- Beijing Key Laboratory of Clinical Epidemiology, School of Public Health, Capital Medical University, Beijing, China
| | - D Q Zheng
- Beijing Key Laboratory of Clinical Epidemiology, School of Public Health, Capital Medical University, Beijing, China
| | - X Y Zhang
- Beijing Key Laboratory of Clinical Epidemiology, School of Public Health, Capital Medical University, Beijing, China
| | - H L Peng
- Beijing Key Laboratory of Clinical Epidemiology, School of Public Health, Capital Medical University, Beijing, China
| | - Z Y Zhao
- Beijing Key Laboratory of Clinical Epidemiology, School of Public Health, Capital Medical University, Beijing, China
| | - D Liu
- Beijing Key Laboratory of Clinical Epidemiology, School of Public Health, Capital Medical University, Beijing, China
| | - Y Sun
- Beijing Key Laboratory of Clinical Epidemiology, School of Public Health, Capital Medical University, Beijing, China
| | - Q Sun
- Beijing Key Laboratory of Clinical Epidemiology, School of Public Health, Capital Medical University, Beijing, China
| | - Q H Li
- Beijing Key Laboratory of Clinical Epidemiology, School of Public Health, Capital Medical University, Beijing, China
| | - J X Zhang
- Beijing Key Laboratory of Clinical Epidemiology, School of Public Health, Capital Medical University, Beijing, China
| | - M Sun
- Beijing Key Laboratory of Clinical Epidemiology, School of Public Health, Capital Medical University, Beijing, China
| | - W J Cao
- Beijing Key Laboratory of Clinical Epidemiology, School of Public Health, Capital Medical University, Beijing, China
| | - A Momčilović
- Genos Glycoscience Research Laboratory, Zagreb, Croatia
| | - G Razdorov
- Genos Glycoscience Research Laboratory, Zagreb, Croatia
| | - L J Wu
- Beijing Key Laboratory of Clinical Epidemiology, School of Public Health, Capital Medical University, Beijing, China
| | - A Russell
- School of Medical and Health Sciences, Edith Cowan University, Perth, WA, Australia
| | - Y X Wang
- Beijing Key Laboratory of Clinical Epidemiology, School of Public Health, Capital Medical University, Beijing, China.
| | - M S Song
- Beijing Key Laboratory of Clinical Epidemiology, School of Public Health, Capital Medical University, Beijing, China. .,School of Medical and Health Sciences, Edith Cowan University, Perth, WA, Australia.
| | - G Lauc
- Genos Glycoscience Research Laboratory, Zagreb, Croatia.,Faculty of Pharmacy and Biochemistry, University of Zagreb, Zagreb, Croatia
| | - W Wang
- Beijing Key Laboratory of Clinical Epidemiology, School of Public Health, Capital Medical University, Beijing, China.,School of Medical and Health Sciences, Edith Cowan University, Perth, WA, Australia
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3
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Lv B, Zhou ST, Peng HL, Ma HW, Wu Y, Zhao X. Successful management of primary splenic pregnancy: a case report and review of literature. CLIN EXP OBSTET GYN 2017; 44:487-488. [PMID: 29949303] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Ectopic pregnancy is defined as dislocation of a fertilized ovum anywhere other than in the cavity of uterus. Generally, the common site for dislocation is within fallopian tube, accounting for 95.5% of all ectopic gestations. Abdominal pregnancy is rare with a potentially life-threatening variation that resides within peritoneal cavity and the primary splenic pregnancy is even rarer. This report describes a patient with primary splenic pregnancy, who was successfully managed after splenectomy.
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4
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Peng HL, Schober HR, Voigtmann T. Velocity autocorrelation function in supercooled liquids: Long-time tails and anomalous shear-wave propagation. Phys Rev E 2016; 94:060601. [PMID: 28085468 DOI: 10.1103/physreve.94.060601] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2016] [Indexed: 06/06/2023]
Abstract
Molecular dynamic simulations are performed to reveal the long-time behavior of the velocity autocorrelation function (VAF) by utilizing the finite-size effect in a Lennard-Jones binary mixture. Whereas in normal liquids the classical positive t^{-3/2} long-time tail is observed, we find in supercooled liquids a negative tail. It is strongly influenced by the transfer of the transverse current wave across the period boundary. The t^{-5/2} decay of the negative long-time tail is confirmed in the spectrum of VAF. Modeling the long-time transverse current within a generalized Maxwell model, we reproduce the negative long-time tail of the VAF, but with a slower algebraic t^{-2} decay.
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Affiliation(s)
- H L Peng
- Institut für Materialphysik im Weltraum, Deutsches Zentrum für Luft- und Raumfahrt (DLR), 51170 Köln, Germany
- Institute for Materials Research, Tohoku University, Sendai 980-8577, Japan
| | - H R Schober
- Peter Grünberg Institut, Forschungszentrum Jülich, D-52425 Jülich, Germany
| | - Th Voigtmann
- Institut für Materialphysik im Weltraum, Deutsches Zentrum für Luft- und Raumfahrt (DLR), 51170 Köln, Germany
- Department of Physics, Heinrich-Heine-Universität Düsseldorf, Universitätsstraße 1, 40225 Düsseldorf, Germany
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5
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Abstract
The growth of the characteristic length scales both for diffusion and viscosity is investigated by molecular dynamics utilizing the finite-size effect in a binary Lennard-Jones mixture. For those quantities relevant to the diffusion process (e.g., the hydrodynamic value and the spatial correlation function), a strong system-size dependence is found. In contrast, it is weak or absent for the shear relaxation process. Correlation lengths are estimated from the decay of the spatial correlation functions. We find the length scale for viscosity decouples from the one of diffusivity, featured by a saturated length even in high supercooling. This temperature-independent behavior of the length scale is reminiscent of the unapparent structure change upon supercooling, implying the manifestation of configuration entropy. Whereas for the diffusion process, it is manifested by relaxation dynamics and dynamic heterogeneity. The Stokes-Einstein relation is found to break down at the temperature where the decoupling of these lengths happens.
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Affiliation(s)
- H L Peng
- Institut für Materialphysik im Weltraum, Deutsches Zentrum für Luft- und Raumfahrt (DLR), 51170 Köln, Germany
| | - Th Voigtmann
- Institut für Materialphysik im Weltraum, Deutsches Zentrum für Luft- und Raumfahrt (DLR), 51170 Köln, Germany
- Department of Physics, Heinrich-Heine-Universität Düsseldorf, Universitätsstraße 1, 40225 Düsseldorf, Germany
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6
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Abstract
We investigate the origin of the breakdown of the Stokes-Einstein relation (SER) between diffusivity and viscosity in undercooled melts. A binary Lennard-Jones system, as a model for a metallic melt, is studied by molecular dynamics. A weak breakdown at high temperatures can be understood from the collectivization of motion, seen in the isotope effect. The strong breakdown at lower temperatures is connected to an increase in dynamic heterogeneity. On relevant time scales some particles diffuse much faster than the average or than predicted by the SER. The van Hove self-correlation function allows one to unambiguously identify slow particles. Their diffusivity is even less than predicted by the SER. The time span of these particles being slow particles, before their first conversion to be a fast one, is larger than the decay time of the stress correlation. The contribution of the slow particles to the viscosity rises rapidly upon cooling. Not only the diffusion but also the viscosity shows a dynamically heterogeneous scenario. We can define a "slow" viscosity. The SER is recovered as the relation between slow diffusivity and slow viscosity.
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Affiliation(s)
- H R Schober
- Peter Grünberg Institut, Forschungszentrum Jülich, 52425 Jülich, Germany
| | - H L Peng
- Institut für Materialphysik im Weltraum, Deutsches Zentrum für Luft- und Raumfahrt (DLR), 51170 Köln, Germany
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7
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Anderson NM, Li D, Peng HL, Laroche FJF, Mansour MR, Gjini E, Aioub M, Helman DJ, Roderick JE, Cheng T, Harrold I, Samaha Y, Meng L, Amsterdam A, Neuberg DS, Denton TT, Sanda T, Kelliher MA, Singh A, Look AT, Feng H. The TCA cycle transferase DLST is important for MYC-mediated leukemogenesis. Leukemia 2016; 30:1365-74. [PMID: 26876595 DOI: 10.1038/leu.2016.26] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2015] [Revised: 12/21/2015] [Accepted: 02/01/2016] [Indexed: 12/22/2022]
Abstract
Despite the pivotal role of MYC in the pathogenesis of T-cell acute lymphoblastic leukemia (T-ALL) and many other cancers, the mechanisms underlying MYC-mediated tumorigenesis remain inadequately understood. Here we utilized a well-characterized zebrafish model of Myc-induced T-ALL for genetic studies to identify novel genes contributing to disease onset. We found that heterozygous inactivation of a tricarboxylic acid (TCA) cycle enzyme, dihydrolipoamide S-succinyltransferase (Dlst), significantly delayed tumor onset in zebrafish without detectable effects on fish development. DLST is the E2 transferase of the α-ketoglutarate (α-KG) dehydrogenase complex (KGDHC), which converts α-KG to succinyl-CoA in the TCA cycle. RNAi knockdown of DLST led to decreased cell viability and induction of apoptosis in human T-ALL cell lines. Polar metabolomics profiling revealed that the TCA cycle was disrupted by DLST knockdown in human T-ALL cells, as demonstrated by an accumulation of α-KG and a decrease of succinyl-CoA. Addition of succinate, the downstream TCA cycle intermediate, to human T-ALL cells was sufficient to rescue defects in cell viability caused by DLST inactivation. Together, our studies uncovered an important role for DLST in MYC-mediated leukemogenesis and demonstrated the metabolic dependence of T-lymphoblasts on the TCA cycle, thus providing implications for targeted therapy.
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Affiliation(s)
- N M Anderson
- Departments of Pharmacology and Medicine, The Center for Cancer Research, Section of Hematology and Medical Oncology, Boston University School of Medicine, Boston, MA, USA
| | - D Li
- Departments of Pharmacology and Medicine, The Center for Cancer Research, Section of Hematology and Medical Oncology, Boston University School of Medicine, Boston, MA, USA
| | - H L Peng
- Department of Pediatric Oncology, Dana-Farber Cancer Institute, Boston, MA, USA.,Division of Hematology/Institute of Molecular Hematology, Second Xiang-Ya Hospital, Central South University, Changsha, China
| | - F J F Laroche
- Departments of Pharmacology and Medicine, The Center for Cancer Research, Section of Hematology and Medical Oncology, Boston University School of Medicine, Boston, MA, USA
| | - M R Mansour
- Department of Pediatric Oncology, Dana-Farber Cancer Institute, Boston, MA, USA
| | - E Gjini
- Department of Pediatric Oncology, Dana-Farber Cancer Institute, Boston, MA, USA
| | - M Aioub
- Departments of Pharmacology and Medicine, The Center for Cancer Research, Section of Hematology and Medical Oncology, Boston University School of Medicine, Boston, MA, USA
| | - D J Helman
- Department of Pediatric Oncology, Dana-Farber Cancer Institute, Boston, MA, USA
| | - J E Roderick
- Department of Cancer Biology, University of Massachusetts School of Medicine, Worcester, MA, USA
| | - T Cheng
- Departments of Pharmacology and Medicine, The Center for Cancer Research, Section of Hematology and Medical Oncology, Boston University School of Medicine, Boston, MA, USA
| | - I Harrold
- Departments of Pharmacology and Medicine, The Center for Cancer Research, Section of Hematology and Medical Oncology, Boston University School of Medicine, Boston, MA, USA
| | - Y Samaha
- Departments of Pharmacology and Medicine, The Center for Cancer Research, Section of Hematology and Medical Oncology, Boston University School of Medicine, Boston, MA, USA
| | - L Meng
- Departments of Pharmacology and Medicine, The Center for Cancer Research, Section of Hematology and Medical Oncology, Boston University School of Medicine, Boston, MA, USA
| | - A Amsterdam
- David H Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - D S Neuberg
- Biostatistics and Computational Biology, Dana-Farber Cancer Institute, Boston, MA, USA
| | - T T Denton
- Department of Pharmaceutical Sciences, Washington State University, College of Pharmacy, Spokane, WA, USA
| | - T Sanda
- Department of Medicine, Cancer Science Institute of Singapore, National University of Singapore, Singapore, Singapore
| | - M A Kelliher
- Department of Cancer Biology, University of Massachusetts School of Medicine, Worcester, MA, USA
| | - A Singh
- Departments of Pharmacology and Medicine, The Center for Cancer Research, Section of Hematology and Medical Oncology, Boston University School of Medicine, Boston, MA, USA
| | - A T Look
- Department of Pediatric Oncology, Dana-Farber Cancer Institute, Boston, MA, USA
| | - H Feng
- Departments of Pharmacology and Medicine, The Center for Cancer Research, Section of Hematology and Medical Oncology, Boston University School of Medicine, Boston, MA, USA
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8
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Li YW, Liu L, Huang PR, Fang W, Luo ZP, Peng HL, Wang YX, Li AX. Chronic streptococcosis in Nile tilapia, Oreochromis niloticus (L.), caused by Streptococcus agalactiae. J Fish Dis 2014; 37:757-763. [PMID: 23952820 DOI: 10.1111/jfd.12146] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/18/2013] [Revised: 05/27/2013] [Accepted: 05/28/2013] [Indexed: 06/02/2023]
Affiliation(s)
- Y W Li
- Key Laboratory for Aquatic Products Safety Department of the Ministry of Education/State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou, Guangdong, China
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9
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Abstract
The structure feature of a model CuZr metallic glass during deformation is investigated by molecular dynamics simulations. A spatially heterogeneous irreversible rearrangement is observed in terms of nonaffine displacement. We find that regions with smaller nonaffine displacement have more Voronoi pentagons, while in those with larger nonaffine displacement other types of faces are more populated. We use the degree of local fivefold symmetry (LFFS) as the structural indicator to predict plastic deformation of local structures and find that the plastic events prefer to be initiated in regions with a lower degree of LFFS and propagate toward regions with a higher degree of LFFS.
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Affiliation(s)
- H L Peng
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190 China
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10
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Chen HY, Chen LK, Su CT, Chen SJ, Lin CH, Tsai YF, Wu CC, Peng HL, Lu TN. Left cervical aortic arch with aneurysm and obstruction: three-dimensional computed tomographic angiography and magnetic resonance angiographic appearance. Int J Cardiovasc Imaging 2002; 18:463-8. [PMID: 12537416 DOI: 10.1023/a:1021155625397] [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] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Cervical arch is a rare congenital anomaly presumed to result from persistence of the third aortic arch and regression of the normal fourth arch. Rather rare is cervical aortic arch associated with aneurysm and obstruction, with eight known cases reported. Definitive diagnosis with a noninvasive imaging modality is desirable and very important to prevent the need for disaster intervention. We present two cases of a pulsatile mass in the left supraclavicular region. Three-dimensional computed tomographic angiography and magnetic resonance angiography clearly showed a left-sided cervical aortic arch (Haughton type D) with arch aneurysm and coarctation (pseudocoarctation).
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Affiliation(s)
- H Y Chen
- Department of Diagnostic Radiology, Shin Kong Wu Ho-Su Memorial Hospital, Taipei, Taiwan, Republic of China
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11
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Abstract
A novel in vivo expression technology (IVET) was performed to identify Klebsiella pneumoniae CG43 genes that are specifically expressed during infection of BALB/c mice. The IVET employed a UDP glucose pyrophosphorylase (galU)-deficient mutant of K. pneumoniae which is incapable of utilizing galactose and synthesizing capsular polysaccharide, as demonstrated by its low virulence to BALB/c mice and a white nonmucoid colony morphology on MacConkey-galactose agar. By using a functional galU gene as the reporter, an IVE promoter could render the galU mutant virulent while maintaining the white nonmucoid colony phenotype. A total of 20 distinct sequences were obtained through the in vivo selection. Five of them have been identified previously as virulence-associated genes in other pathogens, while another five with characterized functions are involved in regulation and transportation of nutrient uptake, biosynthesis of isoprenoids, and protein folding. No known functions have been attributed to the other 10 sequences. We have also demonstrated that 2 of the 20 IVE genes turn on under iron deprivation, whereas the expression of another five genes was found to be activated in the presence of paraquat, a superoxide generator.
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Affiliation(s)
- Y C Lai
- Department of Life Science and Institute of Biotechnology, National Tsing Hua University, Hsin Chu, Taiwan, Republic of China
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12
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Abstract
Klebsiella pneumoniae is a common cause of septicemia and urinary tract infections. The PCR-supported genomic subtractive hybridization was employed to identify genes specifically present in a virulent strain of K. pneumoniae. Analysis of 25 subtracted DNA clones has revealed 19 distinct nucleotide sequences. Two of the sequences were found to be the genes encoding the transposase of Tn3926 and a capsule polysaccharide exporting enzyme. Three sequences displayed moderate homology with bvgAS, which encodes a two-component signal transduction system in Bordetella pertussis. The rest of the sequences did not exhibit homology with any known genes. The distribution of these novel sequences varied greatly in K. pneumoniae clinical isolates, reflecting the heterogeneous nature of the K. pneumoniae population.
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Affiliation(s)
- Y C Lai
- Department of Life Science and Institute of Biotechnology, National Tsing Hua University, Hsin Chu, Taiwan, Republic of China
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13
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Peng HL, Wu CC, Choi WM, Hui MS, Lu TN, Chen LK. Breast cancer detection using magnetic resonance imaging in breasts injected with liquid silicone. Plast Reconstr Surg 1999; 104:2116-20. [PMID: 11149777 DOI: 10.1097/00006534-199912000-00026] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Two patients who had received silicone injections in their breasts several years ago presented with breast complaints. Excluding cancer in these patients was very difficult. Mammograms were very difficult to interpret, as were the physical findings. Carcinoma was successfully detected by magnetic resonance imaging. When women who underwent the injudicious injection of silicone reach the cancer-prone age, the examining physicians should have a greater awareness of the detection and management of carcinoma coexistent with silicone mastopathy. We think that MRI is potentially valuable in the evaluation of the breast lesions; it plays an important role in the detection of breast cancer in breasts augmented with liquid silicone.
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Affiliation(s)
- H L Peng
- Department of Diagnostic Radiology, Shin-Kong Wu Ho-Su Memorial Hospital, Taipei, Taiwan.
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14
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Chang HY, Huang HC, Lee JH, Peng HL. Characterization of a putative Pseudomonas UDPglucose pyrophosphorylase. Proc Natl Sci Counc Repub China B 1999; 23:74-84. [PMID: 10420655] [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: 02/13/2023]
Abstract
A UDP-glucose pyrophosphorylase encoding gene was identified through functional complementation screening by using an Escherichia coli galU mutant. Sequence analysis of the gene indicated that it is most likely derived from a Pseud monas sp. The gene is located immediately upstream and transcribed in the same direction of the gor (glutathione reductase) gene and is capable of encoding a protein 30,943 daltons in size. The gene product synthesized in Escherichia coli was purified and its biochemical properties characterized. The recombinant UDP-glucose pyrophosphorylase exhibited a molecular weight of 130 kDa, suggesting a tetrameric organization of the gene product. Two mutant forms of the enzyme were identified. The activity of the mutant enzyme with a tyrosine to histidine (Y26 1H) substitution was found to be greatly reduced. On the other hand, the tyrosine to cysteine (Y84C) substitution resulted in an enzyme that functions normally at 37 degrees C but rather poorly at temperatures lower than 30 degrees C.
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Affiliation(s)
- H Y Chang
- Department of Life Science, National Tsing Hua University, Hsinchu, Taiwan, R. O. C
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15
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Abstract
The Klebsiella pneumoniae mdcR gene, which encodes a LysR-type regulator, was overexpressed in Escherichia coli. Purified MdcR was found to bind specifically to the control region of either the malonate decarboxylase (mdc) genes or mdcR. We have also demonstrated that MdcR is an activator of the expression of the mdc genes, whereas it represses the transcription of the putative control region of mdcR, PmdcR, indicating a negative autoregulatory control.
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Affiliation(s)
- H L Peng
- Institute of Biological Science and Technology, National Chiao Tung University, Hsin Chu, Taiwan, Republic of China
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16
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Huang YC, Lin TY, Leu HS, Peng HL, Wu JH, Chang HY. Outbreak of Candida parapsilosis fungemia in neonatal intensive care units: clinical implications and genotyping analysis. Infection 1999; 27:97-102. [PMID: 10219638 DOI: 10.1007/bf02560505] [Citation(s) in RCA: 85] [Impact Index Per Article: 3.4] [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: 11/26/2022]
Abstract
During a 5-month period, 17 infants hospitalized in neonatal intensive care units of a medical center and a branch hospital developed 18 episodes of Candida parapsilosis fungemia. The mean age at onset was 35 days. Prior to fungemia, all the infants had received hyperalimentation and antibiotics, and 15 infants had had central venous catheters. The presenting symptoms were variable but only vague in 40% of the episodes. Despite administration of antifungal agents, subsequent eradication of fungemia was achieved in only two-thirds of the episodes. None of the environmental samples was positive for C. parapsilosis, while 20% of hand-washing samples of staff working in both units yielded this microorganism. Four genotypes with two main types were identified from 14 outbreak strains and eight genotypes from 14 hand-washing strains, with one type predominant. The results suggest that C. parapsilosis fungemia increases the morbidity and mortality of neonates but does not cause acute lethal events. The outbreak was caused by two main genotypes, possibly via cross-infection by the hands of health care workers.
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Affiliation(s)
- Y C Huang
- Div. of Infectious Diseases, Chang Gung Children's Hospital
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17
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Peng HL, Cheng SD, Lee JH, Chang HY. Identification of a novel family of human Rab-like small GTP-binding proteins. Proc Natl Sci Counc Repub China B 1999; 23:38-44. [PMID: 9949723] [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: 02/10/2023]
Abstract
The presence of a novel family of Rab-like proteins (Rlp) in the human genome is reported. The gene encoding the Rlp-2 was isolated from a human lymphocyte genomic library. The Rlp-2 gene is intronless and was mapped to chromosome Xq21.3 using fluorescence in situ hybridization. Several cDNA clones encoding the Rlp-1 were identified in a human hippocampus lambda library. Northern analysis revealed a 2.1-kb transcript of Rlp-1 expressed predominantly in brain, heart and skeletal muscle. The transcript was also observed in all examined regions of the human brain at a similar level. An additional gene, termed Rlp-3, which is highly related to Rlp-1 and Rlp-2, was found in the GenBank Data Base. The predicted molecular mass for Rlp is approximately 31 kDa and is consistent with that of Rlp-1 synthesized in Escherichia coli.
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Affiliation(s)
- H L Peng
- Institute of Biological Science and Technology, National Chiao Tung University, Hsinchu, Taiwan, R.O.C
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18
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Abstract
The role of smooth muscle [Ca2+]i and membrane potential for the relaxation to hypercapnic (increased CO2) and normocapnic (unchanged CO2) acidosis is not complete understood. It is often stated that membrane hyperpolarization plays an important role but this has not been vigorously tested. In this study we investigated isolated rat cerebral small arteries under isobaric conditions. Lumen diameter was measured simultaneously with either [Ca2+]i or membrane potential, and acidosis was induced by increasing PCO2 or reducing HCO3- of the bathing solution or by adding HCI to a nominally bicarbonate-free solution. Confocal microscopy verified loading of smooth muscle cells with fluorescent dyes. Acidosis always reduced myogenic tone at transmural pressures between 20 and 120 mmHg. Acidification at a transmural pressure of 40 mmHg caused an increase in diameter and a decrease in [Ca2+]i. This was also seen in the presence of L-NNA and after depolarization with 50 mM K+. The response to hypercapnic and normocapnic acidosis was similar. However, while hypercapnic acidosis caused hyperpolarization, normocapnic acidosis caused depolarization. Dilatation, decrease of [Ca2+]i and depolarization, was also seen with reduction of pH in bicarbonate-free solution. We conclude that the isobaric relaxation to both hypercapnic and normocapnic acidosis is most likely mediated by a reduction of [Ca2+]i. Membrane potential may on the other hand not play a major role for this reduction of [Ca2+]i and it is possible that molecular CO2 has an effect on the membrane potential.
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Affiliation(s)
- H L Peng
- Department of Pharmacology, University of Aarhus, Aarhus C, Denmark
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19
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Peng HL, Lou MD, Chang ML, Chang HY. cDNA cloning and expression analysis of the human UDPglucose dehydrogenase. Proc Natl Sci Counc Repub China B 1998; 22:166-72. [PMID: 9850599] [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: 02/09/2023]
Abstract
A cDNA clone encoding the human UDPglucose dehydrogenase was isolated from a liver cDNA library. The cDNA is 2,355 bp in length with an open reading frame which is capable of encoding a protein of 494 residues. The predicted primary sequence of the gene product is in good agreement with that of the bovine enzyme determined previously found by means of protein sequencing. Two major transcripts of the UDPglucose dehydrogenase gene with sizes of 2.8 and 2.35 kb, respectively, were observed by Northern analysis. The gene was found to be expressed in a variety of tissues with the highest level in liver, consistent with the physiological function of the enzyme in excretion of endo- and xenobiotics compounds.
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Affiliation(s)
- H L Peng
- Institute of Biological Science and Technology, National Chiao-Tung University, Hsin Chu, Taiwan, R.O.C
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20
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Abstract
During a 4-month period, 9 premature infants hospitalized in a neonatal intensive care unit (NICU) developed Candida albicans fungaemia. All 9 infants received antifungal agents. Fluconazole was administered in 7 patients and successfully eradicated this organism in 6 with no adverse effects. For epidemiological investigation, 64 environmental specimens and hand-washings of all 54 staff members involved in the NICU were examined for the presence of this organism. No C. albicans could be identified from environmental sources, while the hand-washing of 1 nurse was C. albicans-positive. Two genotyping methods, including electrophoretic karyotyping using contour-clamped homogeneous electric field gel electrophoresis and polymerase chain reaction-based direct sequencing of rRNA gene, were used in the analysis of the isolates recovered from blood cultures of the infants, the hand-washing of the nurse and 7 control isolates. Both methods yielded comparable results and revealed that all 13 isolates from infected infants as well as the isolate from hand washing of the nurse were of the same genotype while the control isolates were distinct. These results suggest that the outbreak of C. albicans fungaemia was caused by a particular strain and possibly via cross-infection. In addition, we showed that fluconazole seemed to be safe and effective in treating C. albicans fungaemia in neonates, although the data were limited.
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Affiliation(s)
- Y C Huang
- Division of Infectious Diseases, Chang Gung Childrens Hospital, Taoyuan, Taiwan, ROC
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21
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Peng HL, Jensen PE, Nilsson H, Aalkjaer C. Effect of acidosis on tension and [Ca2+]i in rat cerebral arteries: is there a role for membrane potential? Am J Physiol 1998; 274:H655-62. [PMID: 9486271 DOI: 10.1152/ajpheart.1998.274.2.h655] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The cellular mechanism responsible for the reduction of tension in cerebral small arteries to acidosis is not known. In this study the role of smooth muscle intracellular Ca2+ concentration ([Ca2+]i) and membrane potential for the relaxation to acidosis was investigated in isolated rat cerebral small arteries. Isometric force was measured simultaneously with [Ca2+]i (fura 2) or with membrane potential (intracellular microelectrodes), and acidosis was induced by increasing PCO2 or reducing HCO3- of the bathing solution. Both hypercapnic and normocapnic acidosis were associated with a reduction of intracellular pH [measured with 2',7'-bis-(carboxyethyl)-5 (and -6)-carboxyfluorescein], caused relaxation, and reduced [Ca2+]i. However, whereas hypercapnic acidosis caused hyperpolarization, normocapnic acidosis was associated with depolarization. It is concluded that a reduction of [Ca2+]i is in part responsible for the direct effect of the acidosis on the vascular smooth muscle both during normo- and hypercapnia. The mechanism responsible for the reduction of [Ca2+]i differs between the hypercapnic and normocapnic acidosis, being partly explained by hyperpolarization during hypercapnic acidosis, whereas it is seen despite depolarization during normocapnic acidosis.
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Affiliation(s)
- H L Peng
- Department of Pharmacology, University of Aarhus, Denmark
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22
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Lau BH, Lin MI, Sung TC, Wei CP, Peng HL, Lee CC. Holocord intramedullary spinal cord astrocytoma: report of one case. Zhonghua Min Guo Xiao Er Ke Yi Xue Hui Za Zhi 1998; 39:48-50. [PMID: 9553293] [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: 02/07/2023]
Abstract
Intramedullary spinal cord astrocytoma in infants is relatively uncommon. Its occurrence is usually confined to the cervical and cervicothoracic regions. In this paper, we report on the case of a 4-month old male infant with low grade holocord intramedullary spinal cord astrocytoma. He had developed progressive weakness of the lower extremities over a month period. Neurological examination revealed flaccid paraplegia as well as complete loss of all modalities of sensation below the T10 level. MRI revealed a large intramedullary mass which was found to be an intramedullary astrocytoma at surgery. This case report presents the clinical features, radiographic findings, and treatment and outcome for this patient together with a review of relevant literature.
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Affiliation(s)
- B H Lau
- Department of Pediatrics Shin Kong Wu Ho Su Memorial Hospital, Taipei, Taiwan, R.O.C
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23
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Abstract
In this paper, the control of vascular smooth muscle intracellular pH (pHi) and the mechanisms of importance for the vasodilation to acidosis are reviewed. The three transport pathways of importance for the control of pHi are a sodium-coupled bicarbonate transport, a Na,H-exchanger and a Cl,HCO3- exchange. While the two latter pathways are present in all smooth muscle cells studied, the sodium-coupled bicarbonate transport may be present in two forms which are either coupled to chloride efflux or are independent of chloride. The chloride-independent pathway seems electroneutral, indicating a 1:1 stoichiometry. All three transporters can be activated by vasoactive hormones and the second messengers involved are under intense investigation. With respect to the mechanisms involved in the vasodilation to acidosis, there seems to be a nitric oxide-dependent pathway as well as a direct effect of acidosis on the smooth muscle cells. In some preparations, prostanoids may also be involved. The direct vasodilator effect of acidosis is probably mediated through reduction of extracellular pH and the acidosis is associated with a reduction of the intracellular calcium concentration, which could explain the reduction of smooth muscle tone.
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Affiliation(s)
- C Aalkjaer
- Department of Pharmacology, University of Aarhus, Denmark
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24
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Abstract
By using transposon insertional mutagenesis and deletion analyses, a recombinant clone containing the region upstream of the acoABCD operon of Klebsiella pneumoniae was found to be required for acetoin-inducible expression of the operon in Escherichia coli. The nucleotide sequence of the region was determined, and it displayed an open reading frame of 2,763 bp that is transcribed divergently to the acoABCD operon. This gene, designated acoK, is capable of encoding a protein with an overall 58.4% amino acid identity with MalT, the transcriptional activator of the E. coli maltose regulon. A conserved sequence for nucleotide binding at the N-terminal region, as well as a helix-turn-helix motif belonging to the LuxR family of transcriptional regulators at the C terminus, was also identified. Primer extension analysis identified two transcription initiation sites, S1 and S2, located 319 and 267 bp, respectively, upstream of the putative start codon of acoK. Several copies of NtrC recognition sequence [CAC-(N11 to N18)-GTG] were found in the promoter regions of both the acoK gene and the acoABCD operon. Acetoin-dependent expression of the acoABCD operon could be restored in the E. coli acoK mutants by supplying a plasmid carrying an intact acoK, suggesting a transactivating function of the gene product. The AcoK protein overproduced in E. coli was approximately 100 kDa, which is in good agreement with the molecular mass deduced from the nucleotide sequence. A specific DNA binding property and an ATPase activity of the purified AcoK were also demonstrated.
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Affiliation(s)
- H L Peng
- Department of Microbiology, Chang Gung College of Medicine and Technology, Kwei San, Tao Yuan, Taiwan
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25
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Cheng SD, Peng HL, Chang HY. Localization of the human UGP2 gene encoding the muscle isoform of UDPglucose pyrophosphorylase to 2p13-p14 by fluorescence in situ hybridization. Genomics 1997; 39:414-6. [PMID: 9119383 DOI: 10.1006/geno.1996.4426] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Affiliation(s)
- S D Cheng
- Department of Anatomy, Chang Gung College of Medicine and Technology, Kwei-San, Taiwan
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26
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Peng HL, Chen DF, Lan HX, Zhang XM, Gu Z, Jiang MH. Anti-lipid peroxidation of gomisin J on liver mitochondria and cultured myocardial cells. Zhongguo Yao Li Xue Bao 1996; 17:538-41. [PMID: 9863151] [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: 02/09/2023]
Abstract
AIM To study the influences of gomisin J on lipid peroxidation and calcium paradox. METHODS Using two in vitro models of rat liver mitochondria membrane lipid peroxidation (LPO) and cultured myocardial cells. RESULTS Gomisin J inhibited Fe2+/ascorbic acid and ADP/NADPH-induced LPO with IC50 (95% confidence limits) 5.5 (4.5-6.7) and 4.7 (2.8-7.8) mumol.L-1, respectively, when cultured myocardial cells preincubated with Ca(2+)-free medium for 2 min were incubated with normal medium containing Ca2+, a marked increase of malondialdehyde (MDA) formation occurred and gomisin J 10 mumol.L-1 protected myocardial cells through decreasing MDA formation. CONCLUSION Gomisin J inhibits LPO in rat liver mitochondria and protects cultured myocardial cells from being injured by calcium paradox.
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Affiliation(s)
- H L Peng
- Department of Pharmacology, School of Pharmacy, Shanghai Medical University, China
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27
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Duggleby RG, Peng HL, Chang HY. An improved assay for UDPglucose pyrophosphorylase and other enzymes that have nucleotide products. Experientia 1996; 52:568-72. [PMID: 8698091 DOI: 10.1007/bf01969730] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
UDPglucose pyrophosphorylase catalyses the interconversion UDPglucose plus pyrophosphate and glucose 1-phosphate plus UTP. Several assay methods for this enzyme have been described but the only one that can be used to investigate the specificity with respect to various UDPsugars is based on coupling to UTP formation. This assay employs phosphoglycerate kinase to catalyse the formation 1,3- bisphosphoglycerate which is then used to oxidise NADH in the presence of glyceraldehyde 3-phosphate dehydrogenase. We have found that the activity of phosphoglycerate kinase towards UTP is low which limits the usefulness of the assay to very low rates, in agreement with the published recommendation of Hansen et al. Here it is shown that the dynamic range of the assay is increased by more than five fold on addition of nucleoside diphosphate kinase and ADP, which convert UTP to the preferred phosphoglycerate kinase substrate, ATP. It is also shown that the improved assay is suitable for enzymes with other nucleotide triphosphate products.
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Affiliation(s)
- R G Duggleby
- Department of Biochemistry, University of Queensland, Brisbane, Australia.
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28
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Peng HL, Deng WL, Yang YH, Chang HY. Identification and characterization of the acoD gene encoding a dihydrolipoamide dehydrogenase of the Klebsiella pneumoniae acetoin dehydrogenase system. J Biochem 1996; 119:1118-23. [PMID: 8827447 DOI: 10.1093/oxfordjournals.jbchem.a021357] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
The acoD gene, which encodes a dihydrolipoamide dehydrogenase component of the acetoin dehydrogenase enzyme system of Klebsiella pneumoniae was isolated and the nucleotide sequence determined. The gene is capable of encoding a protein of 465 amino acid residues with conserved binding domains for NAD and FAD, and two redox-active cysteine residues. The acoD gene product exhibited a Michaelis constant of 170 microM for NAD, while NADP can not be used as a substrate. The purified enzyme appeared to be a dimer of the acoD gene product. It did not associate tightly with the E1 and E2 components of either acetoin dehydrogenase or 2-oxoglutarate dehydrogenase to form an active multi-enzyme complex.
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Affiliation(s)
- H L Peng
- Department of Microbiology and Immunology, Chang-Gung College of Medicine and Technology, Kwei-San, Taiwan
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29
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Abstract
Non-mucoid mutants of a Klebsiella pneumoniae wild type strain CG43 were generated by transposon mutagenesis. One of the mutants was incapable of fermenting galactose and was designated CG43-17. Alterations of the bacterial surface including capsule, lipopolysaccharides, and several species of outer membrane proteins were noted. The mutant was avirulent to mice and became highly sensitive to human serum. The defects could not be complemented by the gaIETK operon. Diminished activity of UDP-glucose pyrophosphorylase in CG43-17 suggested that it is a gaIU mutant. This possibility was confirmed because the parental phenotypes could be fully restored in the mutant by transforming it with a human liver cDNA encoding UDP-glucose pyrophosphorylase.
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Affiliation(s)
- H Y Chang
- Department of Molecular and Cellular Biology, Chang Gung College of Medicine and Technology, Kwei-San, Taiwan
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30
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Abstract
Consistent with previous results, overexpression of rabbit skeletal muscle glycogen synthase in COS cells did not lead to overaccumulation of glycogen unless activating Ser-->Ala mutations were present at key regulatory phosphorylation sites 2 (Ser7) and 3a (Ser644) in the enzyme. In addition, we found that expression of glycogenin, glycogen branching enzyme, or UDP-glucose pyrophosphorylase alone in COS cells had no effect on the glycogen level. However, coexpression of the hyperactive 2,3a glycogen synthase mutant with either glycogenin or UDP-glucose pyrophosphorylase led to higher glycogen accumulation than that obtained from the expression of glycogen synthase alone. Coexpression of glycogenin with the 2,3a mutant of glycogen synthase led to the appearance of glycogenin with a lower molecular weight suggestive of reduced glucosylation. Increased glycogen synthesis may lead to competition between glycogenin and glycogen synthase for their common substrate UDP-glucose. In summary, we conclude that (i) glycogen synthase is a primary rate-limiting enzyme of glycogen biosynthesis in COS cells, (ii) that phosphorylation of glycogen synthase is regulatory for glycogen accumulation, and (iii) once glycogen synthase is activated, the reaction mediated by UDP-glucose pyrophosphorylase can become rate-determining.
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Affiliation(s)
- A V Skurat
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, 46202-5122, USA
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31
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Abstract
Comparison of the amino acid sequences of five eukaryotic UDPglucose pyrophosphorylases has identified a number of conserved residues that may be important for substrate binding or catalysis. Using the cloned cDNA for the human liver enzyme, we have investigated the role of several of these residues by site-directed mutagenesis. Changing the single conserved cysteine (residue 123) to serine resulted in an active enzyme, as did mutating the single concerned histidine (residue 266) to arginine. The two conserved tryptophans were each altered to serine; W218S is active while W333S is not. In the latter case, the enzyme does not appear to fold correctly, and a similar result was obtained by mutation to lysine at one (residue 391) of the four conserved arginines. The other three arginines are not essential, as judged by the observation that R389H, R422Q and R445H are all active. The kinetic properties of each active mutant were investigated and in most cases were found to be similar to those of wild-type. The most dramatic change is a sevenfold increase in the Km for magnesium pyrophosphate with C123S. Overall, none of these conserved residues appears to be essential for activity, although such a role cannot be ruled out for W333 and R391 where mutation resulted in defective folding.
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Affiliation(s)
- H Y Chang
- Department of Molecular and Cellular Biology, Chang-Gung College of Medicine and Technology, Kwei-San, Taiwan, Republic of China
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32
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Duggleby RG, Chao YC, Huang JG, Peng HL, Chang HY. Sequence differences between human muscle and liver cDNAs for UDPglucose pyrophosphorylase and kinetic properties of the recombinant enzymes expressed in Escherichia coli. Eur J Biochem 1996; 235:173-9. [PMID: 8631325 DOI: 10.1111/j.1432-1033.1996.00173.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
UDP-Glc pyrophosphorylase (EC 2.7.7.9) catalyses the interconversion of MgUTP plus Glc1P and UDP-Glc plus MgPPi. Complementation of an Escherichia coli strain lacking this activity has allowed isolation of cDNA encoding this enzyme from a human muscle library. Two forms were identified and the nucleotide sequence of each was determined; they were found to differ only in the 5' region and we suggest that these arise from the use of a different first exon in the two transcripts. These nucleotide sequences are different from that of the cDNA which was isolated previously from a human liver library [Peng, H.-L. & Chang, H.-Y. (1993) FEBS Lett. 329, 153-158] and it is proposed that these liver and muscle forms are derived from different genes. The cDNA for muscle form I, muscle form II, the liver form, and the liver form fused to part of the lacZ gene were expressed in Escherichia coli and the kinetic properties of each enzyme were characterised. Muscle form I and the LacZ/liver fusion enzyme exhibit Michaelis-Menten kinetics towards all substrates while muscle form II has a sigmoidal dependence of rate upon the concentration of MgPPi. The liver form shows Michaelis-Menten kinetics towards MgUTP. For the remaining three substrates, complex kinetics were observed involving a combination of sigmoidicity at low substrate concentration and partial inhibition at high substrate concentration.
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Affiliation(s)
- R G Duggleby
- Centre for Protein Structure, Function and Engineering, Department of Biochemistry, University of Queensland, Brisbane, Australia
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33
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Abstract
A cosmid clone which was capable of depleting acetoin in vivo was isolated from a library of Klebsiella pneumoniae CG43 cosmids. The smallest functional subclone contained a 3.9-kb DNA fragment of the cosmid clone. Sequencing of the DNA fragment revealed three open reading frames (ORFs A, B, and C) encoding polypeptides of 34, 36, and 52 kDa, respectively. The presence of these proteins was demonstrated by expression of the recombinant DNA clone in Escherichia coli. Considerable similarities between the deduced amino acid sequences of the ORFs and those of the following enzymes were found: acetoin dissimilation enzymes, pyruvate dehydrogenase complex, 2-oxoglutarate dehydrogenase complex, and branched-chain 2-oxo acid dehydrogenase complex of various origins. Activities of these enzymes, including acetoin-dependent dichlorophenolin-dohenol oxidoreductase and dihydrolipoamide acetyltransferase, were detected in the extracts of E. coli harboring the genes encoding products of the three ORFs. Although not required for acetoin depletion in vivo, a possible fourth ORF (ORF D), located 39 nucleotides downstream of ORF C, was also identified. The deduced N-terminal sequence of the ORF D product was highly homologous to the dihydrolipoamide dehydrogenases of several organisms. Primer extension analysis identified the transcriptional start of the operon as an A residue 72 nucleotides upstream of ORF A.
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Affiliation(s)
- W L Deng
- Department of Microbiology and Immunology, Chang Gung College of Medicine and Technology, Tao Yuan, Taiwan
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34
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Abstract
The deaD gene of Klebsiella pneumoniae was isolated and its nucleotide sequence determined. The K. pneumoniae gene is highly homologous with the Escherichia coli analog throughout most of the coding region. The deduced primary sequence of the K. pneumoniae deaD gene product is 659 amino acids in length, in contrast with the 571 amino acids of the E. coli deaD product published previously. Sequence comparison revealed several differences near the 3' end of the deaD genes which result in the frame-shift effect. The 3' end sequence of the E. coli deaD gene was therefore analyzed to verify the discrepancy. Our result indicates that the E. coli deaD gene encodes a product of comparable size to the K. pneumoniae DeaD protein, and the carboxyl terminal sequences of the two proteins are highly homologous. In vivo expression of the K. pneumoniae deaD gene in E. coli yielded a 65-kDa protein. Primer extension analysis of the mRNA from K. pneumoniae identified a major transcription start site at an A residue 44 nt upstream of the first in-frame ATG codon.
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Affiliation(s)
- H L Peng
- Department of Microbiology and Immunology, Chang-Gung Medical College, Kwei-San, Taiwan
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35
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Abstract
A human liver cDNA clone which encodes the UDP-glucose pyrophosphorylase was isolated by complementation of a bacterial galU mutant. The deduced amino acid sequence of the human enzyme comprised 508 amino acids with a calculated molecular mass of 56,950. The human enzyme significantly resembles those of potato tuber and slime mold with a homology of 46.6% and 43.2%, respectively, in amino acid sequence. No homology was found between the eukaryotic and the prokaryotic enzymes. Northern blotting analysis revealed that the gene was expressed at the highest level in skeletal muscle, followed by liver, heart and kidney.
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Affiliation(s)
- H L Peng
- Department of Microbiology and Immunology, Chang-Gung Medical College, Kwei-San, Taiwan, ROC
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36
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Peng HL, Jiang MH, Yang ZC. Determination of beta-adrenoceptor subtypes in human pulmonary artery and thoracic aorta by radioligand binding. Zhongguo Yao Li Xue Bao 1993; 14:298-301. [PMID: 8249619] [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: 01/29/2023]
Abstract
The beta-adrenoceptors of human pulmonary artery (PA) and thoracic aorta (TA) were studied by the use of a high specific activity radioligand [125I]pindolol (Pin). To identify the subtypes of beta-adrenoceptors in the 2 blood vessels, the competitive inhibition curves of [125I]Pin by beta 1-antagonist atenolol and beta 2-agonist salbutamol were analyzed using a computer program LIGAND of a mathematical model of the ligand-binding system. The Bmax (15.3 +/- 1.2 fmol/mg protein) and the dissociation constant Kd (44 +/- 4 pmol.L-1) for PA were similar to those for TA (Bmax, 12.8 +/- 1.2 fmol/mg protein, Kd, 45 +/- 4 pmol.L-1). Competitive inhibition analysis showed that the beta 1- and beta 2-adrenoceptor subtypes coexisted in human PA and TA, with beta 1 adrenoceptor dominant. The ratios of beta 1:beta 2 in PA and TA were 2.9:1.0 and 2.1:1.0, respectively.
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Affiliation(s)
- H L Peng
- Department of Pharmacology, School of Pharmacy, Shanghai Medical University, China
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Abstract
The entire galactose (gal) operon of Klebsiella pneumoniae was isolated and functionally analyzed in Escherichia coli. The genes encoding galactokinase (galK), galactose-1-phosphate uridyltransferase (galT), and UDP-galactose-4-epimerase (galE) were mapped by complementation analysis. The gene order E-T-K was found to be identical to that of Salmonella spp. and E. coli. Analysis of the nucleotide sequence in the control region revealed significant homology with that of E. coli. Two major sites for transcriptional initiation, both mapped to a cytosyl residue, were identified by primer extension. When the operon is expressed in E. coli, the K. pneumoniae gal gene products make up about 30% of the total cellular proteins. The presence of a powerful promoter responsible for high level synthesis of the gal proteins was also demonstrated using beta-galactosidase as reporter.
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Affiliation(s)
- H L Peng
- Department of Microbiology and Immunology, Chang-Gung Medical College, Taiwan
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Peng HL, Wang PY, Wu CM, Hwang DC, Chang HY. Cloning, sequencing and heterologous expression of a Klebsiella pneumoniae gene encoding an FAD-independent acetolactate synthase. Gene 1992; 117:125-30. [PMID: 1644303 DOI: 10.1016/0378-1119(92)90500-o] [Citation(s) in RCA: 20] [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] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The gene encoding the valine-resistant and FAD-independent acetolactate synthase of Klebsiella pneumoniae was isolated and expressed in Escherichia coli. The nucleotide sequence of this gene was determined and it exhibited an open reading frame of 1680 bp in length. In vivo expression of the acetolactate synthase-encoding gene in E. coli revealed a single 60-kDa protein which is consistent with the molecular weight calculated from the deduced amino acid sequence of the gene product. The gene product shares about 20-30% homology with the acetolactate synthases of E. coli, yeast and higher plants.
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Affiliation(s)
- H L Peng
- Department of Microbiology and Immunology, Chang-Gung Medical College, Taiwan, ROC
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Peng HL, Wang PY, Wu JL, Chiu CT, Chang HY. Molecular epidemiology of Klebsiella pneumoniae. Zhonghua Min Guo Wei Sheng Wu Ji Mian Yi Xue Za Zhi 1991; 24:264-71. [PMID: 1726368] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Plasmid profile, restriction fragment length polymorphism (RFLP) patterned by an rRNA probe, and capsule serotyping of 143 Taiwan local bacteriemic isolates of Klebsiella pneumoniae were analyzed. Our results indicate that K1 and K2 are probably the most prevalent serotypes in Taiwan, accounting for 39% of total isolates tested. A remarkable genotypic heterogeneity was observed among these isolates by the analysis of rRNA gene RFLP patterns and plasmid profile, which highlighted differences that were not discerned by the serological tests used to differentiated these strains. On the basis of these analyses, 27 rRNA gene restriction patterns and 57 plasmid profiles were identified.
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Affiliation(s)
- H L Peng
- Department of Microbiology and Immunology, Chang-Gung Memorial Hospital, Lin Kou, Taiwan
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Peng HL, Novick RP, Kreiswirth B, Kornblum J, Schlievert P. Cloning, characterization, and sequencing of an accessory gene regulator (agr) in Staphylococcus aureus. J Bacteriol 1988; 170:4365-72. [PMID: 2457579 PMCID: PMC211451 DOI: 10.1128/jb.170.9.4365-4372.1988] [Citation(s) in RCA: 418] [Impact Index Per Article: 11.6] [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: 01/01/2023] Open
Abstract
We have previously identified a gene in Staphylococcus aureus, agr, whose activity is required for high-level post-exponential-phase expression of a series of secreted proteins. In this paper, we describe the cloning of this gene in Escherichia coli by using an inserted transposon (Tn551) as a cloning probe. The cloned gene, consisting of a 241-codon open reading frame containing the site of the transposon insertion, was recloned to an S. aureus vector, pSK265, and shown to be functional in S. aureus. Activity was evaluated by determinations of alpha-hemolysin, beta-hemolysin, and toxic shock syndrome toxin-1 production in early-stationary-phase cultures. The cloned gene showed considerable variation with respect to different exoproteins and different host strains compared with the chromosomal agr determinant; this variation could not be attributed to the higher copy number of the cloned gene and probably reflects inapparent subtleties of the regulatory system.
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Affiliation(s)
- H L Peng
- Public Health Research Institute, New York, New York 10016
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