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Liu Q, Wang XZ, Mu DB, Li TY, Liu YS, Yu ZY. Correlation analysis of hormone receptors and the expressions of HER-2 and Ki-67 in breast cancer. EUR J GYNAECOL ONCOL 2015; 36:78-83. [PMID: 25872340] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
OBJECTIVE This study aims to investigate the correlation and clinical significance of hormone receptors and the expressions of HER-2 and Ki-67 in breast cancer primary lesions and lymph node metastatic tissues. METHODS 83 cases were studied, who were performed breast cancer surgeries and confirmed the ipsilateral axillary lymph node metastasis by the postoperative pathological diagnosis. Immunohistochemical method was used to simultaneously detect the expressions of ER, PR, HER-2 and Ki-67 in the primary lesions and lymph node metastases. RESULTS ER exhibited the expression concordance rate as 85.5% in primary lesions and metastases, with significant difference (P = 0.039); the expression concordance rates of PR and HER-2 in primary lesions and metastases were 90.4% and 89.2%, respectively, without significant difference (P = 0.289, 0.180); between the Ki-67-highly-expressed primary lesions and Ki-67-lowly-expressed metastases, the expressions of ER in primary lesions and metastases exhibited statistical significance, with P as 0.031. CONCLUSIONS The primary lesions and lymph node metastases had higher consistency, while there was still about 10% patients showed differentiated expression. The simultaneous detection of breast cancer primary lesions and lymph node metastases was still very necessary.
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Xu WJ, Chen LG, Chen X, Liu YS, Zheng TH, Song JJ, Xu W, Li P, Zhang MQ, Xiao CX, Guleng B, Ren JL. Silencing ECHS1 attenuates the proliferation and induces the autophagy of hepatocellular carcinoma via impairing cell metabolism and activating AMPK. Neoplasma 2015; 62:872-80. [PMID: 26458321 DOI: 10.4149/neo_2015_106] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Hepatocellular carcinoma (HCC) is among the most common cancers in the world with a low survival rate. Our previous study showed Short chain enoyl-CoA hydratase (ECHS1) could bind to HBsAg (HBs) and that ECHS1's localization in mitochondria induced HepG2 cell apoptosis. However, the role of the ECHS1 in energy metabolism and autophagy during hepatocellular carcinoma development remains undefined. We aimed to determine what ECHS1 does to energy metabolism and its effects on HCC progression. We performed CCK-8, EdU assays in hepatocellular carcinoma cell lines (HepG2 and HuH7) with stable ECHS1 knock-down. ATP and NADP+/NADPH levels were measured using an colorimetric assay. Our data demonstrated that ECHS1 silencing inhibited cell proliferation and induced autophagy. ECHS1 knockdown did not increase fatty acid synthesis, but decreased cellular ATP. This resulted in AMP-activated protein kinase (AMPK) activation and induced HCC cell autophagy. Our results showed that silencing ECHS1 to attenuate proliferation and induce autophagy may make it a novel cancer therapy target.
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Chang C, Sun J, Xiong ZF, Guo LT, Liu YS, Zhang ZQ, Wu XL. A compact two-way high-power microwave combiner. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2014; 85:084704. [PMID: 25173292 DOI: 10.1063/1.4891698] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
A compact 2-way high-power microwave (HPM) waveguide combiner as an important equipment to realize the coherent microwave combination was theoretically designed, built, and proof-of-principle experimentally tested. The theoretical and experimental S-parameters are basically consistent with each other: return loss <-25 dB, and the isolation degree between 2-channels of the HPM combiner >25 dB to avoid the inter-modulating between the HPM sources. The C-band HPM experiment was carried out, and the power capacity of the HPM combiner was demonstrated to reach multi-gigawatts.
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Qing ZX, Cheng P, Liu XB, Liu YS, Zeng JG, Wang W. Structural speculation and identification of alkaloids in Macleaya cordata fruits by high-performance liquid chromatography/quadrupole-time-of-flight mass spectrometry combined with a screening procedure. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2014; 28:1033-1044. [PMID: 24677525 DOI: 10.1002/rcm.6874] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2013] [Revised: 01/28/2014] [Accepted: 02/17/2014] [Indexed: 06/03/2023]
Abstract
RATIONALE Alkaloids with significant therapeutic effects are the main active constituents of Macleaya cordata, which is a perennial herb plant in the Papaveraceae family. A systematic and novel method for speculating and identifying the structures of alkaloids in M. cordata fruits by high-performance liquid chromatography/quadrupole-time-of-flight mass spectrometry (HPLC/Q-TOF-MS) with a screening procedure was reported. METHODS Investigation of mass spectral fragmentation of alkaloids was carried out based on the tandem mass spectrometry (MS/MS) data analyses of eight reference substances. The skeletons of alkaloids were determined by their ultraviolet spectra (UV) and MS/MS data. The substituent groups of the alkaloids were acquired through a screening procedure developed in our laboratory and MS/MS data. The substituent linkage sites were deduced by MS/MS fragmentation behavior, as well as biosynthetic pathways of related alkaloids. RESULTS The structures of 21 alkaloids were speculated in this study, 10 of which were reported for the first time in M. cordata. Furthermore, benzyltetrahydroisoquinoline and N-methyltetrahydroprotoberberine-type alkaloids were discovered, which indirectly proved that the biosynthetic pathways of benzophenanthridine alkaloids reported in Eschscholtzia california existed in M. cordata as well. CONCLUSIONS HPLC/Q-TOF-MS combined with a screening procedure was a systematic and reliable method for speculating and elucidating the structures of alkaloids. This study might be useful for the identification of other compounds in herbal medicines.
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Gu ZT, Wang H, Li L, Liu YS, Deng XB, Huo SF, Yuan FF, Liu ZF, Tong HS, Su L. Heat stress induces apoptosis through transcription-independent p53-mediated mitochondrial pathways in human umbilical vein endothelial cell. Sci Rep 2014; 4:4469. [PMID: 24667845 PMCID: PMC3966036 DOI: 10.1038/srep04469] [Citation(s) in RCA: 101] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2013] [Accepted: 03/05/2014] [Indexed: 02/07/2023] Open
Abstract
Cells apoptosis induced by intense heat stress is the prominent feature of heat-related illness. However, little is known about the biological effects of heat stress on cells apoptosis. Herein, we presented evidence that intense heat stress could induce early apoptosis of HUVEC cells through activating mitochondrial pathway with changes in mitochondrial membrane potential(ΔΨm), release of cytochrome c, and activation of caspase-9 and -3. We further revealed that p53 played a crucial role in heat stress-induced early apoptosis, with p53 protein rapidly translocated into mitochondria. Using pifithrin-α(PFT), a p53's mitochondrial translocation inhibitor, we found that pretreated with PFT, heat stress induced mitochondrial p53 translocation was significantly suppressed, accompanied by a significant alleviation in the loss of ΔΨm, cytochrome c release and caspase-9 activation. Furthermore, we also found that generation of reactive oxygen species (ROS) was a critical mediator in heat stress-induced apoptosis. In addition, the antioxidant MnTMPyP significantly decreased the heat stress-induced p53's mitochondrial translocation, followed by the loss of ΔΨm, cytochrome c release, caspase-9 activation and heat stress-mediated apoptosis. Conclusively, these findings indicate the contribution of the transcription-independent mitochondrial p53 pathway to early apoptosis in HUVEC cells induced by oxidative stress in response to intense heat stress.
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Tao HF, Liu YS, Fang JL, Su YZ, Chen FH, Zhou LY, Zhu YS. Significance of SODD expression in childhood acute lymphoblastic leukemia and its influence on chemotherapy. GENETICS AND MOLECULAR RESEARCH 2014; 13:2020-31. [PMID: 24737427 DOI: 10.4238/2014.march.24.6] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
This study explored the clinical significance of silencer of death domain (SODD) expression in childhood acute lymphoblastic leukemia (ALL) and its influence on chemotherapy as well as the effect of SODD expression on apoptosis of leukemic cells. The expression of SODD proteins in different ALL groups was determined by immunocytochemistry. The SODD RNAi-interfering plasmid was constructed and transferred to Jurkat cells, and the effects of SODD expression on cell proliferation and apoptosis were analyzed using the MTT and FCM methods. The expressions of SODD, Phospho-NF-κB-P65, Bcl-2, and Caspase 3 were detected by Western blot analysis. The expression of SODD proteins was significantly higher in the ALL groups than in the control group (P < 0.05). The positive expression rate of SODD was significantly higher in refractory/relapsed and clinical high-risk groups than in standard-risk, initial treatment, and complete remission groups (P < 0.05). Microtubule-targeting drugs such as vincristine and taxol can notably down-regulate SODD expression during apoptosis, whereas DNR, and Ara-c cannot. The sensitivity of Jurkat cells to chemotherapeutic drugs increased with down-regulated SODD expression induced by SODD-interfering plasmid transfection. The sensitivity of the cells transfected with SODD-cloning genes decreased. SODD expression was high in the ALL children. These findings indicated that SODD over-expression might be correlated with the clinical classification, curative effect, and prognosis of ALL cells. Microtubule-targeting drugs can specifically down-regulate SODD expression in leukemic cells, thereby increasing the sensitivity of leukemic cells to SODD-targeting chemotherapeutics. In contrast, increased SODD expression tends to reduce sensitivity.
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Zhou XM, Liu YS, Li XJ. Confirmation of a purple-leaved plum graft hybrid. GENETICS AND MOLECULAR RESEARCH 2013; 12:710-3. [PMID: 23546953 DOI: 10.4238/2013.march.11.19] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Fifty-seven scions from an adult purple-leaved plum tree were grafted onto the crown of a 6-year-old Yuhuang plum tree and compared to the control of a non-grafted tree. The floral buds of the purple-leaved plum were fully removed before blossoming to avoid sexual hybridization between the two species. The seeds of the Yuhuang plum were picked in July and sown in the spring after stratification. Three, eleven and eight variants with purplish red leaves were found among the seedlings that grew from the seeds picked in 1999, 2000, and 2001, respectively. The ratio of variant occurrence ranged from 2.3 to 15.8%. Our results confirmed the observation of a graft hybrid by Luther Burbank.
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Lin YH, Liu YS, Lin YC, Wei YS, Liao KS, Lee KR, Lai JY, Chen HM, Jean YC, Liu CY. Decoupling free-carriers contributions from oxygen-vacancy and cation-substitution in extrinsic conducting oxides. JOURNAL OF APPLIED PHYSICS 2013; 113:33706. [PMID: 23405036 PMCID: PMC3562333 DOI: 10.1063/1.4776781] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/07/2012] [Accepted: 01/02/2013] [Indexed: 06/01/2023]
Abstract
The intrinsic oxygen-vacancies and the extrinsic dopants are two major fundamental free-carrier sources for the extrinsic conducting oxides, such as Sn-doped In(2)O(3). Yet, the individual contributions of the above two free-carrier sources to the total carrier concentrations have never been unraveled. A carrier-concentration separation model is derived in this work, which can define the individual contributions to the total carrier concentration from the intrinsic oxygen-vacancies and the extrinsic dopants, separately. The individual contributions obtained from the present carrier-concentration separation model are verified by the two-state trapping model, photoluminescence, and positron annihilation lifetime (PAL) spectroscopy. In addition, the oxygen-vacancy formation energy of the Sn:In(2)O(3) thin film is determined to be 0.25 eV by PAL spectroscopy.
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Li B, Wang C, Zhang Y, Zhao XY, Huang B, Wu PF, Li Q, Li H, Liu YS, Cao LY, Dai WM, Fang WG, Shang DS, Cao L, Zhao WD, Chen YH. Elevated PLGF contributes to small-cell lung cancer brain metastasis. Oncogene 2012; 32:2952-62. [DOI: 10.1038/onc.2012.313] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Liu YS, Hong XK, Feng JF, Yang XF. Fano-Rashba effect in thermoelectricity of a double quantum dot molecular junction. NANOSCALE RESEARCH LETTERS 2011; 6:618. [PMID: 22151740 PMCID: PMC3258288 DOI: 10.1186/1556-276x-6-618] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/25/2011] [Accepted: 12/07/2011] [Indexed: 05/31/2023]
Abstract
We examine the relation between the phase-coherent processes and spin-dependent thermoelectric effects in an Aharonov-Bohm (AB) interferometer with a Rashba quantum dot (QD) in each of its arm by using the Green's function formalism and equation of motion (EOM) technique. Due to the interplay between quantum destructive interference and Rashba spin-orbit interaction (RSOI) in each QD, an asymmetrical transmission node splits into two spin-dependent asymmetrical transmission nodes in the transmission spectrum and, as a consequence, results in the enhancement of the spin-dependent thermoelectric effects near the spin-dependent asymmetrical transmission nodes. We also examine the evolution of spin-dependent thermoelectric effects from a symmetrical parallel geometry to a configuration in series. It is found that the spin-dependent thermoelectric effects can be enhanced by controlling the dot-electrode coupling strength. The simple analytical expressions are also derived to support our numerical results.PACS numbers: 73.63.Kv; 71.70.Ej; 72.20.Pa.
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Liu YS. Telegony, the Sire Effect and non-Mendelian Inheritance Mediated by Spermatozoa: A Historical Overview and Modern Mechanistic Speculations. Reprod Domest Anim 2011; 46:338-43. [DOI: 10.1111/j.1439-0531.2010.01672.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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Huang YH, Liu YS, Hung SY, Li CG, Janabi-Sharifi F. Dynamic phase evaluation in sparse-sampled temporal speckle pattern sequence. OPTICS LETTERS 2011; 36:526-528. [PMID: 21326444 DOI: 10.1364/ol.36.000526] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The rapid progress of modern manufacturing technology has posed stringent requirements for inspecting techniques for vibration characterization and dynamic testing. Because of its simplicity, accuracy, and whole-field character, speckle interferometry has served as one of the major techniques for dynamic measurement, where normally a dense-sampled temporal speckle sequence is captured for phase retrieval using Fourier or wavelet transforms. In this Letter, a method is proposed for phase evaluation of sparse-sampled speckle patterns when the sampling rate is lower than two points per temporal cycle. Dynamic experiments using a high-speed camera demonstrated the effectiveness of the proposed method for complicated wrapped phase retrieval in electronic/digital speckle pattern interferometry.
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Duan GJ, Zhu J, Xu CY, Wan JY, Zhang L, Ge XD, Liu LM, Liu YS. Protective effect of Gö6976, a PKD inhibitor, on LPS/D: -GalN-induced acute liver injury in mice. Inflamm Res 2010; 60:357-66. [PMID: 21063746 DOI: 10.1007/s00011-010-0278-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2010] [Accepted: 10/27/2010] [Indexed: 11/30/2022] Open
Abstract
OBJECTIVE Protein kinase D (PKD) is a newly described serine/threonine protein kinase that plays a pivotal role in inflammatory response. In the present study, we examined the protective effect of Gö6976, a PKD inhibitor, on lipopolysaccharide (LPS) and D: -galactosamine (D: -GalN)-induced acute liver injury in mice. MATERIALS AND METHODS Mice were pretreated intraperitoneally with Gö6976 30 min before LPS/D: -GalN administration . The mortality and degree of hepatic injury was subsequently assessed. RESULTS The results indicated that LPS/D: -GalN administration markedly induced hepatic PKD activation, lethality and liver injury, while pretreatment of the PKD inhibitor Gö6976 significantly inhibited LPS-induced PKD activation, improved the survival of LPS/D: -GalN-administered mice and attenuated LPS/D: -GalN-induced liver injury, as evidenced by reduced levels of serum aminotransferases as well as reduced histopathological changes. In addition, the protective effects of Gö6976 were paralleled by suppressed activation of mitogen-activated protein kinases (MAPKs), decreased expression of tumor necrosis factor-α (TNF-α) and adhesion molecules, and reduced apoptosis and myeloperoxidase (MPO) activity in liver. CONCLUSIONS Our experimental data indicated that Gö6976, a PKD inhibitor, could effectively prevent LPS/D: -GalN-induced acute liver injury by inhibition of MAPKs activation to reduce TNF-α production. This suggests the potential pharmacological value of PKD inhibitors in the intervention of inflammation-based liver diseases.
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Liu YS, Wang JY, Long HL. Analysis of arable land loss and its impact on rural sustainability in Southern Jiangsu Province of China. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2010; 91:646-653. [PMID: 19853366 DOI: 10.1016/j.jenvman.2009.09.028] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2009] [Revised: 09/16/2009] [Accepted: 09/21/2009] [Indexed: 05/28/2023]
Abstract
Rapid urbanization and industrialization in southern Jiangsu Province have consumed a huge amount of arable land. Through comparative analysis of land cover maps derived from TM images in 1990, 2000 and 2006, we identified the trend of arable land loss. It is found that most arable land is lost to urbanization and rural settlements development. Urban settlements, rural settlements, and industrial park-mine-transport land increased, respectively, by 87 997 ha (174.65%), 81 041 ha (104.52%), and 12 692 ha (397.99%) from 1990 to 2006. Most of the source (e.g., change from) land covers are rice paddy fields and dryland. These two covers contributed to newly urbanized areas by 37.12% and 73.52% during 1990-2000, and 46.39% and 38.86% during 2000-2006. However, the loss of arable land is weakly correlated with ecological service value, per capita net income of farmers, but positively with grain yield for some counties. Most areas in the study site have a low arable land depletion rate and a high potential for sustainable development. More attention should be directed at those counties that have a high depletion rate but a low potential for sustainable development. Rural settlements should be controlled and rationalized through legislative measures to achieve harmonious development between urban and rural areas, and sustainable development for rural areas with a minimal impact on the ecoenvironment.
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Liu YS, Wu JY. Use of n-hexadecane as an oxygen vector to improve Phaffia rhodozyma growth and carotenoid production in shake-flask cultures. J Appl Microbiol 2007; 101:1033-8. [PMID: 17040227 DOI: 10.1111/j.1365-2672.2006.03009.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
AIMS To identify beneficial oxygen vectors for Phaffia rhodozyma in liquid cultures, and to evaluate their use to improve the oxygen transfer and carotenoid production in the yeast cultures. METHODS AND RESULTS Several liquid hydrocarbons were tested as oxygen vectors for improving the yeast growth and carotenoid production in shake-flask cultures of P. rhodozyma. While all nontoxic organic liquids (Log P: > or =5.6) showed a positive effect, n-hexadecane was proved to be the most beneficial for the yeast growth and carotenoid production. The addition of 9% (v/v) n-hexadecane to the liquid medium at the time of inoculation was found to be optimal, increasing the carotenoid yield by 58% (14.5 mg l(-1) vs 9.2 g l(-1) in the control) and the oxygen transfer rate (OTR) by 90%. CONCLUSIONS The addition of n-hexadecane to shake-flask cultures of P. rhodozyma significantly improved the oxygen transfer in culture, thus increasing the carotenoid production. SIGNIFICANCE AND IMPACT OF THE STUDY Use of organic oxygen vectors such as n-hexadecane may be a simple and useful means for enhancing oxygen transfer and carotenoid production in liquid fermentation of P. rhodozyma.
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He QY, Cao J, Liu XH, Li MX, Liu YS, Xie JY, Liang SP. DEPD: a novel database for differentially expressed proteins. Bioinformatics 2005; 21:3694-6. [PMID: 16020467 DOI: 10.1093/bioinformatics/bti580] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
SUMMARY The Differentially Expressed Protein Database was designed to store the output of comparative proteomics studies and provides a publicly available query and analysis platform for data mining. The database contains information about more than 3000 differentially expressed proteins (DEPs) manually extracted from the published literature, including relevant biological, experimental and methodological elements. Tools for visualization and functional analysis of DEPs are provided via a user-friendly webinterface. AVAILABILITY http://protchem.hunnu.edu.cn/depd/.
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Balic A, Bowles VM, Liu YS, Meeusen ENT. Local immune responses in sensitized sheep following challenge infection with Teladorsagia circumcincta. Parasite Immunol 2004; 25:375-81. [PMID: 14521580 DOI: 10.1046/j.1365-3024.2003.00646.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Sheep were sensitized by weekly infections with Teladorsagia circumcincta over a 9-week period. After a 12-week rest, sheep were divided into four groups and killed without challenge or 3, 5 and 10 days post challenge (DPC) with 50000 L3. Recovery of challenge larvae from abomasal scrapings was highest at 3 DPC while no parasites were recovered by 10 DPC. Abomasal lymph nodes (ALN) of challenged sheep were significantly larger at 5 DPC, coinciding with an increase in the proportion of CD4 T cells and a decrease in CD21+ cells, probably reflecting the loss of CD21 from terminally differentiated antibody secreting cells. A significant increase was observed in gammadelta-TCR+ cells at 3 DPC in the ALN, while their number slightly decreased in the abomasal tissues throughout the challenge period. The number of tissue eosinophils was dramatically increased after challenge compared with the unchallenged controls, with a peak at 3 DPC, coinciding with the peak in larval recovery. CD4+ cells significantly increased in the abomasal tissues at 5 DPC, while no changes in globule leucocytes were observed until 10 DPC. Antibody-secreting cell probes (ASC-probes) generated from the ALN showed highest reactivity against larval antigens at 5 DPC. This reactivity was predominantly directed against regions between 90 and 100 kDa and 30-35 kDa in the L3 preparation and lower molecular weight antigens in the L4. No reactivity was observed against the adult extract. The 30-35 kDa antigen seemed to exist as a high molecular weight complex in L3 homogenate and was not susceptible to protease K treatment, suggesting it may be non-protein in nature.
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Perozo E, Cuello LG, Cortes DM, Liu YS, Sompornpisut P. EPR approaches to ion channel structure and function. NOVARTIS FOUNDATION SYMPOSIUM 2002; 245:146-58; discussion 158-64, 165-8. [PMID: 12027005 DOI: 10.1002/0470868759.ch10] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
The fundamental processes that underlie ion channel function are permeation/ selectivity and gating. In an effort to understand ion channel gating, we have used an approach that combines reporter-group spectroscopic techniques (spin labelling/ electron paramagnetic resonance, EPR) and electrophysiological methods with classical biochemical and molecular biological procedures. As an ideal test channel, we have focused our attention on the K+ channel from Streptomyces lividans, KcsA. Through site-directed spin labelling, cysteine chemistry was used to introduce nitroxide radicals into specific sites within KcsA with high reactivity and specificity. EPR spectroscopy analysis of the spin labelled mutants yields two types of structural information: (1) mobility and solvent accessibility of the attached nitroxide through collisional relaxation methods and (2) distances between pairs of nitroxides through dipole-dipole interactions. Using this approach, we analysed the correlation between KcsA crystal structure and the EPR data, extend it to derive low-resolution folds of full-length KcsA and apply it in the determination of the molecular rearrangements responsible for pH-dependent gating.
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Leung HY, Yip SK, Cheon C, Liu YS, Lau J, Wong HK, Chung KH. A randomized controlled trial of tolterodine and oxybutynin on tolerability and clinical efficacy for treating Chinese women with an overactive bladder. BJU Int 2002; 90:375-80. [PMID: 12175392 DOI: 10.1046/j.1464-410x.2002.02905.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Objective To compare the tolerability and clinical efficacy of tolterodine and oxybutynin in the treatment of Hong Kong Chinese women with an overactive bladder. Patients and methods A randomized controlled trial was conducted at two urogynaecology centres in Hong Kong. In all, 106 women with urodynamically confirmed detrusor instability were recruited. Baseline severity assessments included a visual analogue scale (VAS), urinary diary and urinary pad-test. The women were randomized to receive either oral tolterodine 2 mg or oxybutynin 5 mg twice daily for 10 weeks. Treatment responses were assessed at 4 and 10 weeks using the VAS and urinary diary. Treatment tolerability was assessed at baseline, 4 and 10 weeks using the Xerostomia Questionnaire. A urinary pad-test was repeated at 10 weeks. Results The perceived change from baseline VAS was better in the tolterodine than the oxybutynin group after 10 weeks of treatment (per-protocol analysis, P = 0.043). The two drugs were effective in reducing the symptoms of frequency (P < 0.001). Tolterodine was significantly better than oxybutynin in reducing urinary leakage (urinary pad-test; median change - 5.00 g vs 0 g, P = 0.019). Both drugs caused a significant worsening of dry mouth (overall dryness, P < 0.005; discomfort, P < 0.005; sleep, P = 0.021; speaking, P = 0.045; swallowing, P = 0.004; and liquid consumption, P = 0.017). Conclusions Both oxybutynin and tolterodine were effective in ameliorating the severity of the symptoms of detrusor instability. Tolterodine was better than oxybutynin in both subjective and objective outcome measures, but both drugs caused similar worsening of dry mouth that may limit the tolerability of these medications.
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Fridman E, Liu YS, Carmel-Goren L, Gur A, Shoresh M, Pleban T, Eshed Y, Zamir D. Two tightly linked QTLs modify tomato sugar content via different physiological pathways. Mol Genet Genomics 2002; 266:821-6. [PMID: 11810256 DOI: 10.1007/s00438-001-0599-4] [Citation(s) in RCA: 100] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2001] [Accepted: 09/21/2001] [Indexed: 10/27/2022]
Abstract
Congenic lines that differ in a single defined chromosome segment are useful for the study of complex phenotypes, as they allow isolation of the effect of a particular quantitative trait locus (QTL) from those of the entire genome. We conducted high-resolution QTL mapping of a 9-cM introgression, originating from the wild tomato species Lycopersicon pennellii, in two extremely different genetic and physiological backgrounds. In the "indeterminate" glasshouse background we identified only a single QTL ( Brix9-2-5) that affects the total soluble solids of the fruit [mainly sugars, measured in Brix units (B)]. This QTL was previously delimited within the gene for an apoplastic invertase, Lin5, that modulates sugar partitioning to the fruit. Analysis of the effects of the same chromosome segment in "determinate", open-field tomatoes, revealed two QTLs, 0.3 cM apart: the fruit-specific Brix9-2-5 that affects B only, and the shoot-specific PW9-2-5, which accounts for an altered growth habit resulting in increases in plant weight, yield, and B. This study highlights the power of the congenic approach for dissecting developmental pathways leading to complex phenotypes.
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Sompornpisut P, Liu YS, Perozo E. Calculation of rigid-body conformational changes using restraint-driven Cartesian transformations. Biophys J 2001; 81:2530-46. [PMID: 11606268 PMCID: PMC1301722 DOI: 10.1016/s0006-3495(01)75898-5] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
We present an approach for calculating conformational changes in membrane proteins using limited distance information. The method, named restraint-driven Cartesian transformations, involves 1) the use of relative distance changes; 2) the systematic sampling of rigid body movements in Cartesian space; 3) a penalty evaluation; and 4) model refinement using energy minimization. As a test case, we have analyzed the structural basis of activation gating in the Streptomyces lividans potassium channel (KcsA). A total of 10 pairs of distance restraints derived from site-directed spin labeling and electron paramagnetic resonance (SDSL-EPR) spectra were used to calculate the open conformation of the second transmembrane domains of KcsA (TM2). The SDSL-EPR based structure reveals a gating mechanism consistent with a scissoring-type motion of the TM2 segments that includes a pivot point near middle of the helix. The present approach considerably reduces the amount of time and effort required to establish the overall nature of conformational changes in membrane proteins. It is expected that this approach can be implemented into restrained molecular dynamics protocol to calculate the structure and conformational changes in a variety of membrane protein systems.
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Wen L, Chen L, Liu YS. [Relationship between basic fibroblast growth factor (bFGF) and cell proliferation, invasion in pituitary adenoma]. HUNAN YI KE DA XUE XUE BAO = HUNAN YIKE DAXUE XUEBAO = BULLETIN OF HUNAN MEDICAL UNIVERSITY 2001; 26:466-8. [PMID: 12536505] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
Abstract
Basic fibroblast growth factor (bFGF) and proliferating cell nuclear antigen (PCNA) were examined by immunohistochemistry in fifty-one pituitary adenomas. The results showed that the intensity of bFGF expression was strong or intermediate in twenty-nine adenomas, which was positively related to cell proliferation, there was positive relationship between bFGF expressin and tumor invasion in non-functional adenomas. The data suggest that bFGF may play some role in the origin and progression of pituitary adenomas.
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Liu YS, Sompornpisut P, Perozo E. Structure of the KcsA channel intracellular gate in the open state. NATURE STRUCTURAL BIOLOGY 2001; 8:883-7. [PMID: 11573095 DOI: 10.1038/nsb1001-883] [Citation(s) in RCA: 169] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Ion channels catalyze the selective transfer of ions across the membrane in response to a variety of stimuli. These channels gate by controlling the access of ions to a centrally located water-filled pore. The crystal structure of the Streptomyces lividans potassium channel (KcsA) has allowed a molecular exploration of this mechanism. Electron paramagnetic resonance (EPR) studies have uncovered significant conformational changes at the intracellular end of the second transmembrane helix (TM2) upon gating. We have used site-directed spin labeling (SDSL) and EPR spectroscopy in an attempt to quantify the structural rearrangements of the KcsA TM2 bundle underlying the transition from the closed to the open state. Under conditions favoring the closed and open conformations, 10 intersubunit distances were obtained across TM2 segments from tandem dimer constructs. Analysis of these data points to a mechanism in which each TM2 helix tilts away from the permeation pathway, towards the membrane plane, and rotates about its helical axis, supporting a scissoring-type motion with a pivot point near residues 107-108. These movements are accompanied by a large increase in the diameter of the vestibule below the central water-filled cavity.
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Zhang YH, Liu YS, Liu SM. [Study of acute supratentorial and infratentorial localized lesions by transcranial Doppler]. HUNAN YI KE DA XUE XUE BAO = HUNAN YIKE DAXUE XUEBAO = BULLETIN OF HUNAN MEDICAL UNIVERSITY 2001; 26:383-6. [PMID: 12536747] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
Abstract
OBJECTIVE To evaluate the correlation between increased intracranial pressure in supratentorial, infratentorial and TCD parameters of basal arteries. METHODS Sixteen New Zealand white rabbits were randomly divided into two groups: supratentorial group and infratentorial group. Intracranial pressures were raised after inflation of a preplaced epidural balloons. TCD parameters of the BA, rMCA were examined at intervals of 15 minutes after inflation of the balloon. ICP, ASP, HR, R were also recorded simultaneously. RESULTS 1. The normal spectra of BA were characterized by a high-resistance, low-flow waveform. 2. At the 0.4 ml, 0.5 ml balloon volume level, ICP in supratentorial group was significantly increased than that in infratentorial group; 3. The correlation between ICP and MCA's TCD parameters were better than that between ICP and BA's TCD parameters in the supratentorial group. In the infratentorial group, the correlation between ICP and BA's TCD parameters were better than that between ICPs and MCA's TCD. CONCLUSIONS 1. There are intracranial pressure gradients in mass lesions, so fibroptic probe should be placed at the place where the mass lesion takes place. 2. To perform non-invasive ICP monitoring by TCD, the basal artery should be chosen according to the mass lesions.
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Wang J, Liu YS, Liu SM. [Changes in somatosensory evoked potentials and brainstem auditory evoked potentials during acute intracranial hypertension in rabbits]. HUNAN YI KE DA XUE XUE BAO = HUNAN YIKE DAXUE XUEBAO = BULLETIN OF HUNAN MEDICAL UNIVERSITY 2001; 26:197-9. [PMID: 12536678] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
Abstract
OBJECTIVE To study the changes in somatosensory evoked potentials (SEPs) and brainstem auditory evoked potentials (BAEPs) during intracranial hypertension. METHOD A rabbit model of acute intracranial hypertension was developed. Thirty New Zealand rabbits were divided into 3 group. Both Group A and B were groups with intracranial hypertension; Group C was the control group. In Group A, balloons were placed to the right parietal lobe beneath the dura mater; in Group B, to temporal at the middle fossa near the brainstem. RESULT (1) In Group A, when ICP rose to (1.48 +/- 0.35) kPa, P1 amplitude of SEPs was significantly changed, whereas latencies of Wave IV, V, and VII of BAEPs were prolonged when ICP rose to (9.40 +/- 1.60) kPa. In group B, P1 amplitude of SEPs was changed when ICP reached (8.10 +/- 1.25) kPa, and latency of Wave III of BAEPs was prolonged when ICP rose to (3.11 +/- 0.80) kPa. (2) P1 amplitude increased with ICP value when the balloon volume increased from V = 0.0 ml, ICP = (0.43 +/- 0.10) kPa to V = 0.4 ml, ICP = (2.44 +/- 0.65) kPa and then decreased afterward. CONCLUSIONS (1) Changes in SEPs and BAEPs relate to not only ICP value but also the location of the balloon. (2) With the increasing of ICP, P1 amplitude increases firstly and then decreases.
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