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Huong DT, Walker TM, Ha DT, Ngoc KTT, Trung VN, Nam LT, Ngoc PTT, Nguyet LT, Thanh NT, Minh NH, Cuong NK, Khiem NV, Ngoc HVT, Bich TTT, Hong HN, Trieu PP, Lan LK, Lan K, Hue NN, Huong NTL, Thao TLTN, Quang NL, Anh TDD, Crook DW, Thwaites GE, Thuong NTT, Hoa NB, Luong DV, Hung NV. The implementation of whole-genome sequencing for Mycobacterium tuberculosis in Vietnam. IJTLD OPEN 2024; 1:320-322. [PMID: 39035433 PMCID: PMC11257095 DOI: 10.5588/ijtldopen.24.0147] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/22/2024] [Accepted: 05/14/2024] [Indexed: 07/23/2024]
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Zhou J, Lan K, Yang F. P35.26 Comparative Genomic Profiling of Lung Adenocarcinoma in Self-Reported Asian and White Patients, a Propensity Matched Study of 1400 Samples. J Thorac Oncol 2021. [DOI: 10.1016/j.jtho.2021.01.727] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Nie K, Guo X, Zhou X, Zhang Z, Zhang C, Lan K, Ji Y. Irinotecan combined with oxaliplatin and S1 in patients with metastatic pancreatic adenocarcinoma. Ann Oncol 2019. [DOI: 10.1093/annonc/mdz247.033] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Lan K, Zhou J, Yang F, Wang J. P1.14-21 Propensity-Matched Genomic Profiling Comparison of Lung Adenocarcinomas Among 3 Races, a Multicenter Study of 4655 Patients. J Thorac Oncol 2019. [DOI: 10.1016/j.jtho.2019.08.1172] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Lan K, Yang WB, Zhang XW, Bai WJ, Li Q, Xu T. [Application of flurbiprofen axetil in pain management associated during transrectal ultrasound-guided prostate biopsy]. BEIJING DA XUE XUE BAO. YI XUE BAN = JOURNAL OF PEKING UNIVERSITY. HEALTH SCIENCES 2017; 49:643-647. [PMID: 28816281] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
OBJECTIVE To examine the effects of perioperative intravenous administration of flurbiprofen axetil (FA) on pain associated with transrectal ultrasound-guided prostate biopsy. METHODS This was a randomized,controlled study. Eighty-one patients who underwent 12 core prostate biopsy were included in the study. The patients were randomly assigned to one of three groups (n=27 in each) by type of procedure during prostate biopsy. Group intrarectal local anesthesia (IRLA) received intrarectal 5% (0.05 g/L) lidocaine gel 60 mg, 5 minutes before the procedure alone; Group FA received intravenous flurbiprofen axetil (1 mg/kg) 1 hour before the procedure; Group IRLA+FA received intrarectal 5% lidocaine gel 60 mg, 5 minutes before the procedure and intravenous flurbiprofen axetil (1 mg/kg) 1 hour before the procedure. The patients were asked to score the pain by using visual analogue scale (VAS) in 4 situations,including when the probe was inserted (VASI),during anesthesia (VAS II),during biopsy (VAS III) and 20 minutes after biopsy (VAS IV). The findings were evaluated with analysis of variance,and the Tukey post hoc test was followed with an overall 2-tailed significance level at α =0.05. P1, P value between Group IRLA and Group FA; P2, P value between Group FA and Group IRLA +FA, P3, P value between Group IRLA and Group IRLA +FA. The bonferroni method was used to adjust the test level, α=0.017,a P value of less than 0.017 was accepted as the threshold for statistical significance. RESULTS No major complications,including sepsis and severe rectal bleeding,were noted in any patient. There were no differences in general condition of the patients before procedure among the 3 groups. There were statistically significant differences in VAS scores among the 3 groups in VAS II (5.7±2.2, 3.0±1.5,3.3±1.9,respectively,P=0.012) and VAS III (6.7±2.3,3.0±2.1,2.9±1.6,respectively,P=0.001). There were no differences in the pain scores among the 3 groups during probe insertion (VAS I, 3.2±1.0,4.1±2.1,4.2±1.7, respectively,P=5.752) and 20 minutes after biopsy (VAS IV, 1.4±2.1,1.0±0.9,1.1±0.7,respectively,P=3.772). Between-column differences among the 3 groups were VAS II (P1=0.007,P2=5.655,P3=0.001,respectively) and VAS III(P1=0.008,P2=7.517,P3=0.001,respectively),the differences between Group IRLA and Group FA,Group IRLA and Group IRLA +FA in VAS II and VAS III were statistically significant. CONCLUSION The intravenous flurbiprofen axetil was found to be more effective than intrarectal lidocaine gel alone.
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Zhang XW, Lan K, Yang WB, Li Q, Zhao YP, Yin HQ, Kite B, Bai WJ, Xu T. [Expression and localization of transmembrane protein CMTM2 in human testis and sperm]. BEIJING DA XUE XUE BAO. YI XUE BAN = JOURNAL OF PEKING UNIVERSITY. HEALTH SCIENCES 2017; 49:575-579. [PMID: 28816268] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
OBJECTIVE To study the expression of transmembrane protein CMTM2 in the testis and sperm of adult males and to approach the potential function of the protein in the male reproductive system. METHODS The expression of CMTM2 in human testis and sperm was confirmed by Western blot. Immunohistochemical staining was used for detecting CMTM2 localization in the testis tissue, TRITC-CMTM2 and FITC-Hoechst double immunofluorescence staining was performed to examine the subcellular localization of CMTM2 in the human sperm before and after acrosome reaction, that is, immunofluorescent staining was used for detecting CMTM2 localization in both the testis and sperm before and after the acrosome reaction. RESULTS CMTM2 was presented in both human testis and sperm. In the testis, CMTM2 immunoreactive particles were observed mainly in the membrane of the different stages of spermatogenic cells. In the human sperm, its immunoreactivity was restrictively localized to the posterior head where sperm-egg fusion occurred, and the CMTM2 localization was not affected by sperm acrosome reaction. CMTM2 was widely expressed in seminiferous tubules of the human testis, mainly in the cell membranes of spermatogenic cells, which was consistent with the previous reports. The immunofluorescence performed on frozen human testis slides showed similar findings with immunohistochemistry, which gave weight to the localization of CMTM2 in the cell membranes of spermatogenic cells at different stages. TRITC-CMTM2 and FITC-Hoechst double immunofluorescence staining was performed to examine the subcellular localization of CMTM2 in the human sperm before and after acrosome reaction. CMTM2 was localized at the posterior head of sperm before and after acrosome reaction. The localization and expression of CMTM2 were not affected by sperm acrosome reaction. CONCLUSION Expression of CMTM2 in the male reproductive system of the adult human exhibits cell- and region-specific patterns, which suggests that they may play an important role in spermatogenesis and sperm-egg fusion. The expression of CMTM2 in the male reproductive system of the adult human exhibits cell- and region-specific patterns, which suggests that they may play an important role in spermatogenesis and sperm-egg fusion. However, it still remains to be further elucidated about the definite role of CMTM2 in male reproductive system and the process of spermatogenesis. And in vitro fertilization experiments are needed to confirm the role of CMTM2 in fertilization in future.
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Ren G, Yan J, Liu J, Lan K, Chen YH, Huo WY, Fan Z, Zhang X, Zheng J, Chen Z, Jiang W, Chen L, Tang Q, Yuan Z, Wang F, Jiang S, Ding Y, Zhang W, He XT. Neutron Generation by Laser-Driven Spherically Convergent Plasma Fusion. PHYSICAL REVIEW LETTERS 2017; 118:165001. [PMID: 28474938 DOI: 10.1103/physrevlett.118.165001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2016] [Indexed: 06/07/2023]
Abstract
We investigate a new laser-driven spherically convergent plasma fusion scheme (SCPF) that can produce thermonuclear neutrons stably and efficiently. In the SCPF scheme, laser beams of nanosecond pulse duration and 10^{14}-10^{15} W/cm^{2} intensity uniformly irradiate the fuel layer lined inside a spherical hohlraum. The fuel layer is ablated and heated to expand inwards. Eventually, the hot fuel plasmas converge, collide, merge, and stagnate at the central region, converting most of their kinetic energy to internal energy, forming a thermonuclear fusion fireball. With the assumptions of steady ablation and adiabatic expansion, we theoretically predict the neutron yield Y_{n} to be related to the laser energy E_{L}, the hohlraum radius R_{h}, and the pulse duration τ through a scaling law of Y_{n}∝(E_{L}/R_{h}^{1.2}τ^{0.2})^{2.5}. We have done experiments at the ShengGuangIII-prototype facility to demonstrate the principle of the SCPF scheme. Some important implications are discussed.
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Lai S, Huang C, Wang C, Chen Y, Lan K, Cheng A, Kuo S. Effect of Immunohistochemical Biological Expression on Clinical Outcome for Patients With Breast Cancer and Brain Metastases After Brain Radiation Therapy. Int J Radiat Oncol Biol Phys 2014. [DOI: 10.1016/j.ijrobp.2014.05.900] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Han J, Jin M, Zhang P, Liu J, Wang L, Wen D, Wu X, Liu G, Zou Y, Lv X, Dong X, Shao B, Gu S, Zhou D, Leng Q, Zhang C, Lan K. Epidemiological link between exposure to poultry and all influenza A(H7N9) confirmed cases in Huzhou city, China, March to May 2013. Euro Surveill 2013; 18:20481. [PMID: 23725866] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/02/2023] Open
Abstract
We analysed the association between influenza A(H7N9) confirmed cases and exposure to poultry in Huzhou city, China. All cases (n=12) had a history of direct exposure to poultry or live poultry markets. We detected A(H7N9)-positive poultry samples from each site that was epidemiologically associated with cases. None of the cases’ close contacts tested positive. After closure of the markets, no new cases were identified, suggesting an epidemiological link between poultry exposure and A(H7N9) virus infection.
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Han J, Jin M, Zhang P, Liu J, Wang L, Wen D, Wu X, Liu G, Zou Y, Lv X, Dong X, Shao B, Gu S, Zhou D, Leng Q, Zhang C, Lan K. Epidemiological link between exposure to poultry and all influenza A(H7N9) confirmed cases in Huzhou city, China, March to May 2013. Euro Surveill 2013. [DOI: 10.2807/ese.18.20.20481-en] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Binary file ES_Abstracts_Final_ECDC.txt matches
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Shao Y, Sun X, Lan K, Bircher C. WE-C-217BCD-10: Development of High Performance PET for Animal Imaging and Therapy Applications. Med Phys 2012; 39:3951. [PMID: 28520023 DOI: 10.1118/1.4736126] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
PURPOSE A prototype small animal PET is developed with several novel technologies to measure 3D gamma-interaction positions and to substantially improve imaging performance. METHODS Each new detector has an 8×8 array of 1.95×1.95×30 mm̂3 LYSO scintillators, with each end optically connected to a solid-state photo multiplier (SSPM) array through a light guide. This dual-ended-readout enables the depth-of-interaction (DOI) measurement. Each SSPM array has 16 SSPMs arranged in a 4×4 matrix. Each SSPM has active area about 3×3 mm̂2, with its output read by an ASIC electronics that directly converts analog signals to digital timing pulses which encode the interaction information for energy, timing, crystal of interaction, and DOI calculations. These digital pulses are transferred to and decoded by FPGA-based TDC for coincident event selection and data acquisition. This independent readout of each SSPM and parallel signal process significantly improve signal-to-noise ratio and permit applying flexible data processing algorithms. The current prototype system consists of two rotating detector panels on a portable gantry, with 4 detectors linearly packed together in each panel to provide ∼16 mm axial and variable trans- axial FOV with adjustable panel-to-panel distance. List-mode OSEM-based image reconstruction with resolution modeling was implemented. Both Na- 22 point source and phantom were used to evaluate the system performance. RESULTS The measured energy, timing, spatial and DOI resolutions for each crystal were around 16%, 2.6 ns, 2.0 mm and 5.0 mm, respectively. The measured spatial resolutions with DOI were ∼1.7 mm across the entire FOV in all direction, while those without DOI were much worse and non-uniform across the FOV, in the range predominately around 3.0 to 4.0 mm. In addition, images from a F-18 hot-rod phantom with DOI show significantly improved quality compared to those without DOI. CONCLUSIONS DOI- measurable PET shows substantially improved image performance for a compact system. National Institute of Health. University of Texas MD Anderson Cancer Center.
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Verma SC, Lan K, Robertson E. Structure and function of latency-associated nuclear antigen. Curr Top Microbiol Immunol 2006; 312:101-36. [PMID: 17089795 PMCID: PMC3142369 DOI: 10.1007/978-3-540-34344-8_4] [Citation(s) in RCA: 89] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Latency-associated nuclear antigen (LANA) encoded by open reading frame 73 (ORF73) is the major latent protein expressed in all forms of KSHV-associated malignancies. LANA is a large (222-234 kDa) nuclear protein that interacts with various cellular as well as viral proteins. LANA has been classified as an oncogenic protein as it dysregulates various cellular pathways including tumor suppressor pathways associated with pRb and p53 and can transform primary rat embryo fibroblasts in cooperation with the cellular oncogene Hras. It associates with GSK-3beta, an important modulator of Wnt signaling pathway leading to the accumulation of cytoplasmic beta-catenin, which upregulates Tcf/Lef regulated genes after entering into the nucleus. LANA also blocks the expression of RTA, the reactivation transcriptional activator, which is critical for the latency to lytic switch, and thus helps in maintaining viral latency. LANA tethers the viral episomal DNA to the host chromosomes by directly binding to its cognate binding sequence within the TR region of the genome through its C terminus and to the nucleosomes through the N terminus of the molecule. Tethering to the host chromosomes helps in efficient partitioning of the viral episomes in the dividing cells. Disruptions of LANA expression led to reduction in the episomal copies of the viral DNA, supporting its role in persistence of the viral DNA. The functions known so far suggest that LANA is a key player in KSHV-mediated pathogenesis.
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Xu SX, Lan K, Shan YL, Wang H, Luo JY, Cui F, Huang YS, Meng JP, Zhang XM, Yin YB. Real-time quantitative assay of HCV RNA using the duplex scorpion primer. Arch Virol 2006; 152:431-40. [PMID: 16991014 DOI: 10.1007/s00705-006-0843-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2005] [Accepted: 07/31/2006] [Indexed: 10/24/2022]
Abstract
A novel real-time quantitative method for detecting HCV in serum was established in which the duplex scorpion primer was used to provide a unimolecular probing mechanism for hybridizing the highly conserved 5' noncoding region (5' NCR) of the HCV genome specifically. Through methodological evaluation, we found this new method had a wide linearity, high sensitivity, repeatability and specificity. Compared to the commercial TaqMan method, this method was found to be more sensitive and less costly, and the final results were obtained more quickly. Therefore, it could be applied to diagnose and monitor HCV infection in clinical practice.
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Lan K, Chen XL. Crystal structure of (diphenylphosphinoyl)phenylmethanol, C19H17O2P. Z KRIST-NEW CRYST ST 2006. [DOI: 10.1524/ncrs.2006.0026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
AbstractC19H17O2P, monoclinic, P121/n1 (no. 14), a = 11.239(4) Å, b = 6.310(2) Å, c = 22.157(8) Å, β = 92.091(7)°, V = 1570.3Å3, Z = 4, Rgt(F) = 0.041, wRref(F2) = 0.114, T = 293 K.
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Lan K, Chen XL. Crystal structure of(diphenylphosphinoyl) phenylmethanol,C19H17O2P. Z KRIST-NEW CRYST ST 2006. [DOI: 10.1524/ncrs.2006.221.14.171] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Miyoshi T, Sarsour M, Yuan L, Zhu X, Ahmidouch A, Ambrozewicz P, Androic D, Angelescu T, Asaturyan R, Avery S, Baker OK, Bertovic I, Breuer H, Carlini R, Cha J, Chrien R, Christy M, Cole L, Danagoulian S, Dehnhard D, Elaasar M, Empl A, Ent R, Fenker H, Fujii Y, Furic M, Gan L, Garrow K, Gasparian A, Gueye P, Harvey M, Hashimoto O, Hinton W, Hu B, Hungerford E, Jackson C, Johnston K, Juengst H, Keppel C, Lan K, Liang Y, Likhachev VP, Liu JH, Mack D, Margaryan A, Markowitz P, Martoff J, Mkrtchyan H, Nakamura SN, Petkovic T, Reinhold J, Roche J, Sato Y, Sawafta R, Simicevic N, Smith G, Stepanyan S, Tadevosyan V, Takahashi T, Tanida K, Tang L, Ukai M, Uzzle A, Vulcan W, Wells S, Wood S, Xu G, Yamaguchi H, Yan C. High resolution spectroscopy of the 12Lambda B hypernucleus produced by the (e,e'K+) reaction. PHYSICAL REVIEW LETTERS 2003; 90:232502. [PMID: 12857252 DOI: 10.1103/physrevlett.90.232502] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2002] [Indexed: 05/24/2023]
Abstract
High-energy, cw electron beams at new accelerator facilities allow electromagnetic production and precision study of hypernuclear structure, and we report here on the first experiment demonstrating the potential of the (e,e'K+) reaction for hypernuclear spectroscopy. This experiment is also the first to take advantage of the enhanced virtual photon flux available when electrons are scattered at approximately zero degrees. The observed energy resolution was found to be approximately 900 keV for the (12)(Lambda)B spectrum, and is substantially better than any previous hypernuclear experiment using magnetic spectrometers. The positions of the major excitations are found to be in agreement with a theoretical prediction and with a previous binding energy measurement, but additional structure is also observed in the core excited region, underlining the future promise of this technique.
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Ren CP, Lan K, Liu WD, He ZW, Wang H, Yao KT. [Infection of mutated mouse complement receptor type II by Epstein-Barr virus]. HUNAN YI KE DA XUE XUE BAO = HUNAN YIKE DAXUE XUEBAO = BULLETIN OF HUNAN MEDICAL UNIVERSITY 2001; 26:98-102. [PMID: 12536634] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/19/2023]
Abstract
Site-directed mutagenesis method was used to introduce two desired mutations, which were confirmed by DNA sequencing, into mouse complement receptor Type II gene(MCR2). Then the constructed eukaryotic expression vectors containing wild type mouse CR2/1(wtMCR2/1), mutant type mouse CR2/1 (mtMCR2/1) and human CR2 (hCR2) cDNA were transferred into mouse SP2/0 cells by electroporation. After two-week screening by G418, the stably transfected clones were obtained. Several ways including PCR, RT-PCR, and immunohistochemistry were utilized to screen those clones with interesting genes integrated and expressed. Then Epstein-Barr virus(EBV) was used to infect these transfected cells and EBER-1 (EBV encoded RNAs) hybridization results showed that only hCR2 and mtMCR2 transfected SP2/0 cells could be infected by EBV, but positive rate of the former was much higher than the latter. This study sets groundwork for elucidating the mechanism by which EBV enters the cells and for establishing the animal model of EBV-related nasopharyngeal carcinoma (NPC).
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Lan K, Jorgenson JW. A hybrid of exponential and gaussian functions as a simple model of asymmetric chromatographic peaks. J Chromatogr A 2001; 915:1-13. [PMID: 11358238 DOI: 10.1016/s0021-9673(01)00594-5] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
A hybrid of exponential and Gaussian functions is developed as a model of asymmetric peak profiles. This exponential-Gaussian hybrid function (EGH) is mathematically simple, numerically stable, and its parameters are readily determined by making graphical measurements and applying simple equations. Furthermore, the statistical moments of the EGH function can be accurately approximated (within+/-0.15% error) at any level of asymmetry using formulae that are easily programmed into a computer. These features of the EGH make it very easy to implement by most chromatographers. The EGH serves as a useful alternative to the exponentially modified Gaussian (EMG) for modeling slightly asymmetric peaks since the two models produce nearly the same profile at relatively low asymmetries. The EGH also serves as an addition to the extensive list of alternative models that are sometimes better than the EMG at describing highly asymmetric peaks. A comparison between EMG and EGH curves at various asymmetries is made by analysis of toluene, phenylalanine, and pyridine on a reversed-phase liquid chromatographic system.
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Wade SM, Lan K, Moore DJ, Neubig RR. Inverse agonist activity at the alpha(2A)-adrenergic receptor. Mol Pharmacol 2001; 59:532-42. [PMID: 11179449 DOI: 10.1124/mol.59.3.532] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Constitutive activation of G protein-coupled receptors (GPCRs) is now well recognized and many classical GPCR antagonists have been found to be inverse agonists. For the alpha(2A)-adrenergic receptor (AR) we determine the relative inverse efficacies of a series of antagonists and utilize the extended ternary complex model to estimate the fraction of constitutively active mutant (CAM) receptors in the active state. Stable Chinese hamster ovary cell lines expressing the porcine alpha(2A)-AR in its wild-type (WT) and constitutively activated (CAM-T373K) form were isolated. Activation of both G(i) and G(s) was enhanced for CAM receptors. cAMP production was suppressed in cells with the CAM alpha(2A)-AR and this suppression was reversed by alpha(2)-adrenergic antagonists with an order of inverse efficacy of rauwolscine > yohimbine > RX821002 > MK912, whereas phentolamine and idazoxan were essentially neutral antagonists. This striking difference in inverse efficacy between idazoxan and RX821002 may account for in vivo pharmacological differences between these two alpha(2)-adrenergic antagonists. Agonist binding affinity to the non-G protein-coupled CAM receptor was 3- to 9-fold higher than to WT, whereas binding of the most efficacious inverse agonists, yohimbine and rauwolscine, was 1.7- and 2.1-fold weaker. Analysis of this difference by the extended ternary complex model indicates that approximately 50% of the CAM alpha(2A)-AR is in the active (R*) state although there is no detectable constitutive activity of the WT receptor in the absence of agonist.
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Lan K, Jorgenson JW. Spatial and temporal progressions of spatial statistical moments in linear chromatography. J Chromatogr A 2001; 905:47-57. [PMID: 11206807 DOI: 10.1016/s0021-9673(00)00988-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Generalizations of existing models of chromatography allow the spatial and temporal progressions of all spatial statistical moments in linear chromatography to be given as the solution to a set of ordinary differential equations. Basic strategies of simplifying these equations are described.
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Otsuka M, Kato N, Lan K, Yoshida H, Kato J, Goto T, Shiratori Y, Omata M. Hepatitis C virus core protein enhances p53 function through augmentation of DNA binding affinity and transcriptional ability. J Biol Chem 2000; 275:34122-30. [PMID: 10924497 DOI: 10.1074/jbc.m000578200] [Citation(s) in RCA: 132] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Hepatitis C virus (HCV) causes a persistent infection, chronic hepatitis, and hepatocellular carcinoma. Since there are several reports indicating that some viruses influence the tumor suppressor p53 function, we determined the effects of HCV proteins on p53 function and its mechanism determined by use of a reporter assay. Among seven HCV proteins investigated (core, NS2, NS3, NS4A, NS4B, NS5A, and NS5B), only core protein augmented the transcriptional activity of p53 and increased the expression of p21(waf1) protein, which is a major target of p53. Core protein increased both DNA-binding affinity of p53 in electrophoretic morbidity shift assay and transcriptional ability of p53 itself in a reporter assay. The direct interaction between core protein and C terminus of p53 was also shown by glutathione S-transferase fusion protein binding assay. In addition, core protein interacted with hTAF(II)28, a component of the transcriptional factor complex in vivo and in vitro. These results suggest that HCV core protein interacts with p53 and modulates p53-dependent promoter activities during HCV infection.
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Kato N, Yoshida H, Ono-Nita SK, Kato J, Goto T, Otsuka M, Lan K, Matsushima K, Shiratori Y, Omata M. Activation of intracellular signaling by hepatitis B and C viruses: C-viral core is the most potent signal inducer. Hepatology 2000; 32:405-12. [PMID: 10915750 DOI: 10.1053/jhep.2000.9198] [Citation(s) in RCA: 173] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
To clarify the effects of hepatitis C virus (HCV) infection on hepatocytes, we analyzed and compared the induction of intracellular signals by HCV and hepatitis B virus (HBV) proteins. We examined the influence of 7 HCV (core, NS2, NS3, NS4A, NS4B, NS5A, and NS5B) and 4 HBV (precore, core, polymerase, and X) proteins on 5 well-defined intracellular signaling pathways associated with cell proliferation, differentiation, and apoptosis by use of a reporter assay. Viral protein-expression vectors were cotransfected into mammalian cells with reporter vectors having a luciferase gene driven by the following inducible cis-enhancer elements: the cyclic adenosine monophosphate response element, the serum response element (SRE), and the binding sites for nuclear factor kappaB (NF-kappaB), activator protein 1 (AP-1), and serum response factor (SRF). In addition, the activation of signals by HCV proteins was examined in a reporter plasmid having a natural interleukin-8 (IL-8) promoter upstream of a luciferase gene. Of 11 HCV and HBV proteins, HCV core had the strongest influence on intracellular signals, especially NF-kappaB-, AP-1-, and SRE-associated pathways. HCV core's activation level exceeded that of HBV X protein, a well-characterized transactivator of these signals. Moreover, HCV core activated the IL-8 promoter through NF-kappaB and AP-1. For the other proteins, HCV NS4B showed signal activation, but signals were activated at a lesser extent. The luciferase reporter assay, a recently introduced technique, helped in the elucidation of molecular events underlying the inflammatory and proliferation process in the liver induced by HCV.
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Xie L, Xu L, He Z, Zhou W, Wang L, Zhang L, Lan K, Ren C, Liu W, Yao K. Identification of differentially expressed genes in nasopharyngeal carcinoma by means of the Atlas human cancer cDNA expression array. J Cancer Res Clin Oncol 2000; 126:400-6. [PMID: 10929762 DOI: 10.1007/pl00008488] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
PURPOSE To investigate genes of critical areas, including cell cycle/growth control, apoptosis, oncogene/tumor suppressors and growth factor/cytokines, that are differentially expressed in nasopharyngeal carcinoma. METHODS The Human Cancer cDNA Atlas, which contains 588 genes relating to tumor biology, was used to screen normal nasopharyngeal tissue, nasopharyngeal cancer (NPC). The reverse transcription/polymerase chain reaction was used to confirm the expression pattern of some genes identified by Atlas hybridization. RESULTS The differentially expressed cell cycle/growth control regulators in NPC showed a stronger tendency toward cell proliferation with the up-regulation of cyclin D1, cyclin D2 etc. The expression pattern of apoptosis-related genes demonstrated the up-regulation of both anti-apoptotic factors such as the BCL-2-related protein A1, TRAF3, the inhibitor of apoptosis protein A1 (IAPI) and apoptotic pathway elements such as Fas/Apo-1, Apo-2 ligand etc. Among oncogenes/tumor suppressors, MDM2, STAT1 and STAT2 were found to be up-regulated in NPC. The expression profile of growth factors/cytokines showed the up-regulation of many growth-enhancing factors such as EGR1, tumor-derived growth factor 1, platelet-derived growth factor A chain etc. as well as Th1-type cytokines e.g. interleukin-1beta and interferons. A smaller number of genes were down-regulated in nasopharyngeal cancer, such as those encoding ERK1, Raf, secreted apoptosis-related protein 1, CD27BP, transforming growth factor beta2, pre-B-cell-stimulating factor homologue etc. CONCLUSION The consistent tendency toward cell proliferation, the possibility of a stronger antiapoptotic force that operates on the normal apoptotic pathway, or the autocrine or paracrine growth factors may account for the development of NPC. Some genes are reported for the first time to have changed expression in nasopharyngeal carcinoma. The simple, quick, and high-throughput method of profiling gene expression by cDNA array hybridization provides us with a quick overview of key factors that may be involved in NPC, and may identify genes suitable for further study of carcinogenesis mechanism or targets for possible molecular diagnosis or therapy.
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Liu W, Ren C, Shi J, Feng X, He Z, Xu L, Lan K, Xie L, Peng Y, Fan J, Kung HF, Yao KT, Xu RH. Characterization of the functionally related sites in the neural inducing gene noggin. Biochem Biophys Res Commun 2000; 270:293-7. [PMID: 10733942 DOI: 10.1006/bbrc.2000.2415] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Previously we have shown that blocking bone morphogenetic protein (BMP) receptor signaling by a dominant negative BMP receptor causes neurogenesis in Xenopus animal caps (ACs), whereas the physiological neural inducer noggin acts as a homodimer physically binding to BMP-4 and disrupting its signaling at the ligand level. The present study attempted to elucidate the relationship between the structure and function of noggin. By replacing some cysteine residues with serine residues through a site-directed mutagenesis strategy, we generated three noggin mutants, C145S, C205S, and C(218, 220, 222)S (3CS). Although mRNAs encoded by these mutants were translated as efficiently as wild-type (WT) noggin mRNA, they behaved differently when expressed in vivo. Expression of WT noggin or C205S in Xenopus ACs converted the explants (prospective ectoderm) into neural tissue, indicated by the neural-like morphology and expression of the pan neural marker NCAM in the ACs. In contrast, ACs expressing C145S or 3CS sustained an epidermal fate like the control caps. Similar results were observed in the mesoderm where C205S (but not C145S and 3CS) displayed dorsalizing activity as well as WT noggin. Altogether, our results suggest that Cys145 alone or Cys(218, 220, 222) as a whole in noggin protein is required for the biological activities of noggin, probably participating in the dimerization of noggin with BMP-4 or itself.
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Lan K, Jorgenson JW. Theoretical investigation of the spatial progression of temporal statistical moments in linear chromatography. Anal Chem 2000; 72:1555-63. [PMID: 10763252 DOI: 10.1021/ac990533u] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Migration and dispersion in chromatography are modeled by analogy to an effective eddy diffusion process. On the basis of this model, the spatial rates of temporal statistical moment change are derived for general chromatography in linear media. In most practical cases, these equations can be simplified so that temporal statistical moments can be calculated by solving a system of ordinary differential equations that depend only on the local HETP, solute velocity, and initial values of the temporal statistical moments. The calculations of temporal centroid, temporal variance, temporal skew, and temporal excess are demonstrated for the case of linear solvent strength gradients. It is shown for the case of temporally invariant separation environments, such as isocratic liquid chromatographic systems and isothermal gas chromatographic systems, that temporal variance contributions are spatially additive and that the temporal third normalized central moment is unaffected by spatial variations in the medium. A refined explanation is given for how peak symmetry is improved in gradient forms of chromatography.
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