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Kan XZ, Li XF, Lei ZP, Wang M, Chen L, Gao H, Yang ZY. Complete mitochondrial genome of Cabot's tragopan, Tragopan caboti (Galliformes: Phasianidae). GENETICS AND MOLECULAR RESEARCH 2010; 9:1204-16. [PMID: 20589618 DOI: 10.4238/vol9-2gmr820] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Cabot's tragopan, Tragopan caboti, is a globally threatened pheasant endemic to southeast China. The complete mitochondrial genome of Cabot's tragopan was sequenced. The circular genome contains 16,727 bp, encoding a standard set of 13 protein-coding genes, two ribosomal RNA genes, and 22 transfer RNA genes, plus the putative control region, a structure very similar to that of other Galliformes. As found in other vertebrates, most of these genes code on the H-strand, except for the NADH dehydrogenase subunit 6 (nad6) and eight tRNA genes (Gln, Ala, Asn, Cys, Tyr, Ser(UCN), Pro, Glu). All protein-coding genes initiated with ATG, except for cox1, which began with GTG, and had a strong skew of C vs G (GC skew = -0.29 to -0.73). One extra 'C' nucleotide was found in the NADH dehydrogenase subunit 3 (nad3). All the tRNA gene sequences have the potential to fold into typical cloverleaf secondary structures. Conserved sequences in three domains were identified within the control region (D-loop). These results provide basic information for phylogenetic analyses among Galliform birds, and especially Tragopan species.
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Gnutek P, Yang ZY, Rudowicz C. Modeling local structure using crystal field and spin Hamiltonian parameters: the tetragonal Fe(K)(3+)-O(I)(2-) defect center in KTaO(3) crystal. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2009; 21:455402. [PMID: 21694012 DOI: 10.1088/0953-8984/21/45/455402] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The local structure and the spin Hamiltonian (SH) parameters, including the zero-field-splitting (ZFS) parameters D and (a+2F/3), and the Zeeman g factors [Formula: see text] and [Formula: see text], are theoretically investigated for the Fe(K)(3+)-O(I)(2-) center in KTaO(3) crystal. The microscopic SH (MSH) parameters are modeled within the framework of the crystal field (CF) theory employing the CF analysis (CFA) package, which also incorporates the MSH modules. Our approach takes into account the spin-orbit interaction as well as the spin-spin and spin-other-orbit interactions omitted in previous studies. The superposition model (SPM) calculations are carried out to provide input CF parameters for the CFA/MSH package. The combined SPM-CFA/MSH approach is used to consider various structural models for the Fe(K)(3+)-O(I)(2-) defect center in KTaO(3). This modeling reveals that the off-center displacement of the Fe(3+) ions, Δ(1)(Fe(3+)), combined with an inward relaxation of the nearest oxygen ligands, Δ(2)(O(2-)), and the existence of the interstitial oxygen O(I)(2-) give rise to a strong tetragonal crystal field. This finding may explain the large ZFS experimentally observed for the Fe(K)(3+)-O(I)(2-) center in KTaO(3). Matching the theoretical MSH predictions with the available structural data as well as electron magnetic resonance (EMR) and optical spectroscopy data enables predicting reasonable ranges of values of Δ(1)(Fe(3+)) and Δ(2)(O(2-)) as well as the possible location of O(I)(2-) ligands around Fe(3+) ions in KTaO(3). The defect structure model obtained using the SPM-CFA/MSH approach reproduces very well the ranges of the experimental SH parameters D, [Formula: see text] and [Formula: see text] and importantly yields not only the correct magnitude of D but also the sign, unlike previous studies. More reliable predictions may be achieved when experimental data on (a+2F/3) and/or crystal field energy levels become available. Comparison of our results with those arising from alternative models existing in the literature indicates considerable advantages of our method and presumably higher reliability of our predictions.
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Yang ZY, Zhao M. A study of the porosities of polymer nanoporous films using numerical simulations and experimental methods. ACTA ACUST UNITED AC 2007. [DOI: 10.1088/1464-4258/9/10/017] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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79
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Yang ZY, Lu YF. Broadband nanowire-grid polarizers in ultraviolet-visible-near-infrared regions. OPTICS EXPRESS 2007; 15:9510-9. [PMID: 19547298 DOI: 10.1364/oe.15.009510] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Broadband nanowire-grid polarizers were designed and numerically simulated using the finite difference time domain (FDTD) method. Using a broadband stimulation source, optical properties of the polarizers were analyzed in the ultraviolet (UV)-visible-near infrared (NIR) regions. Specifically, the extinction ratios and optical transmittances of transverse magnetic (TM) and transverse electric (TE) modes were characterized for different metal materials and geometrical parameters including wire-grid periods, metal-wire fill ratios, and spacing between wire-grid layers. Based on the simulation results, an extra broadband polarizer with an average extinction ratio higher than 70 dB and transmission efficiency over 64% in the range of 0.3 to 5 mum was proposed.
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80
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Yang ZY, Lu W, Luk KDK, Lee R. Errors in the Measurement of Lumbar Spine Motions Using Skin Mounted Sensors. J Biomech 2007. [DOI: 10.1016/s0021-9290(07)70588-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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81
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Yin L, Song XF, Qu SF, Huang T, Mei JP, Yang ZY, Li J. Performance evaluation of a dental handpiece in simulation of clinical finishing using a novel 2DOF in vitro apparatus. Proc Inst Mech Eng H 2006; 220:929-38. [PMID: 17236525 DOI: 10.1243/09544119jeim98] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
This paper reports on the performance evaluation of a dental handpiece in simulation of clinical finishing using a novel two-degrees-of-freedom (2DOF) in vitro apparatus. The instrumented apparatus consisted of a two-dimensional computer-controlled coordinate worktable carrying a dental handpiece, a piezoelectric force dynamometer, and a high-speed data acquisition and signal conditioning system for simulating the clinical operations and monitoring the dental finishing processes. The performance of the dental handpiece was experimentally evaluated with respect to rotational speed, torque, and specific finishing energy under the applied clinical finishing conditions. The results show that the rotational speeds of the dental handpiece decreased by increasing either the depth of cut or the feed rate at a constant clinically applied air pressure and water flowrate. They also decreased when increasing both the tangential and normal finishing forces. The specific finishing energy decreased with an increase in either depth of cut or feed rate, while the finishing torque increased as either the depth of cut or the feed rate was increased. Implications of these results were to provide guidance for proper applications of dental handpieces in clinical practice.
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Wang X, Ji M, Wang JF, Liu Z, Yang ZY. Anaerobic uptake of phosphate in an anaerobic-aerobic granular sludge sequencing batch reactor. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2006; 53:63-70. [PMID: 16841728 DOI: 10.2166/wst.2006.266] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
An unusual phenomenon of anaerobic phosphate uptake under alternating anaerobic/aerobic condition was observed in a granular sludge sequencing batch reactor, fed with acetate as sole organic substrate. Anaerobic phosphate uptake efficiencies remained at 50-70% as the influent P/COD was increased from 2/100 to 4/100, and results showed that anaerobic uptake of phosphate was correlated with anaerobic absorption of acetate. Excluding the main possibility of chemical phosphate removal, it appeared that phosphate uptake during the anaerobic phase was associated with organisms enriched in the reactor. Moreover, results indicated that intracellular glycogen was used as the main energy source of organics anaerobic absorption and intracellular polymers storage. Measuring and analysing the variation of phosphate, organic substrate, intracellular glycogen and pH in the anaerobic phase, a preliminary explanation was developed that anaerobic uptake of phosphate was the demand of intracellular glycogen degradation, and extracellular phosphate was transported to intracellular by pH gradient-sensitive phosphate carrier protein.
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83
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Yang ZY, Liu GQ. Effect of p-glycoprotein inhibitor combinations on drug efflux from rat brain microvessel endothelial cells. DIE PHARMAZIE 2004; 59:952-6. [PMID: 15638085] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/01/2023]
Abstract
In an effort to develop a clinically useful approach to inhibit the drug efflux across the blood brain barrier (BBB) mediated by P-glycoprotein (P-gp), the combined inhibitory effect of four P-gp inhibitors: cyclosporin A (CsA), verapamil (Ver), tetrandrine (Tet) and doxorubicin (Dox), was evaluated by determining the intracellular concentration of rhodamine 123 in in vitro cultured rat brain microvessel endothelial cells (BMEC). The results showed that CsA combined with Ver or Tet synergistically inhibited P-gp mediated efflux of Rh123 from rat BMEC, suggesting that the combined application of P-gp inhibitors would possibly be a useful approach to increase drug concentration in brain tissues, enhance the therapeutic effect and reduce the toxicity of drugs.
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84
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Lowndes IS, Fogarty T, Yang ZY. The application of genetic algorithms to optimise the performance of a mine ventilation network: the influence of coding method and population size. Soft comput 2004. [DOI: 10.1007/s00500-004-0364-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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85
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Muetterties EL, Bleeke JR, Yang ZY, Day VW. Complexity in the reductive reaction of cobalt(II) chloride in the presence of phosphites. Isolation of stable, noninterconvertible Co[P(OCH3)3]4 and Co2[P(OCH3)3]8 molecules. J Am Chem Soc 2002. [DOI: 10.1021/ja00374a049] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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86
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Zhang M, Yang ZY, Binns CW, Lee AH. Diet and ovarian cancer risk: a case-control study in China. Br J Cancer 2002; 86:712-7. [PMID: 11875731 PMCID: PMC2375319 DOI: 10.1038/sj.bjc.6600085] [Citation(s) in RCA: 83] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2001] [Accepted: 11/19/2001] [Indexed: 11/08/2022] Open
Abstract
This case-control study, conducted in Zhejiang, China during 1999-2000, investigated whether dietary factors have an aetiological association with ovarian cancer. Cases were 254 patients with histologically confirmed epithelial ovary cancer. The 652 controls comprised 340 hospital visitors, 261 non-neoplasm hospital outpatients without long-term diet modifications and 51 women recruited from the community. A validated food frequency questionnaire was used to measure the habitual diet of cases and controls. The risks of ovarian cancer for the dietary factors were assessed by adjusted odds ratios based on multivariate logistic regression analysis, accounting for potential confounding demographic, lifestyle, familial factors and hormonal status, family ovarian cancer history and total energy intake. The ovarian cancer risk declined with increasing consumption of vegetables and fruits but vice versa with high intakes of animal fat and salted vegetables. The adjusted upper quartile odds ratio compared to the lower quartile was 0.24 (0.1-0.5) for vegetables, 0.36 (0.2-0.7) for fruits, 4.6 (2.2-9.3) for animal fat and 3.4 (2.0-5.8) for preserved (salted) vegetables with significant dose-response relationship. The risk of ovarian cancer also appeared to increase for those women preferring fat, fried, cured and smoked food.
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87
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Xia Y, Yang ZY, Xia P, Hackl T, Hamel E, Mauger A, Wu JH, Lee KH. Antitumor Agents. 211. Fluorinated 2-phenyl-4-quinolone derivatives as antimitotic antitumor agents. J Med Chem 2001; 44:3932-6. [PMID: 11689079 DOI: 10.1021/jm0101085] [Citation(s) in RCA: 112] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Fluorinated 2-phenyl-4-quinolone derivatives were synthesized and evaluated in National Cancer Institute's 60 human tumor cell line in vitro screen. From the results, the ketone moiety plays an essential role in activity. Among the compounds tested, 2'-fluoro-6-pyrrol-2-phenyl-4-quinolone (13) exhibited the most potent cytotoxic activities (log GI(50) < -8.00) against renal and melanoma tumor cell lines. Compound 13 was also a potent inhibitor of tubulin polymerization (IC(50) = 0.46 microM) and of radiolabeled colchicine binding to tubulin, with activities comparable to those of the potent antimitotic natural products colchicine, podophyllotoxin, and combretastatin A-4.
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88
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He M, Yang ZY, Nie YF, Wang J, Xu P. A new type of class I bacterial 5-enopyruvylshikimate-3-phosphate synthase mutants with enhanced tolerance to glyphosate. BIOCHIMICA ET BIOPHYSICA ACTA 2001; 1568:1-6. [PMID: 11731078 DOI: 10.1016/s0304-4165(01)00181-7] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Glyphosate or Roundup is the most extensively used herbicide for broad-spectrum control of weeds. Glyphosate inhibits 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS), a key enzyme in the aromatic amino acid biosynthetic pathway in microorganisms and plants. Applying the staggered extension process, we randomly mutated and recombined the aroA genes of Salmonella typhimurium and Escherichia coli to obtain four variants that exhibit significantly enhanced tolerance to glyphosate. All four mutants are chimeras of the two parental genes and, in addition, three of them carry one or more de novo point mutations. None of the amino acid substitutions in the mutants was in a position previously known to be important for catalysis or substrate binding. Kinetic analysis of EPSPS activity from these mutants indicated that the tolerance was attributed to a 2-10-fold increased specific activity, 0.4-8-fold reduced affinity to glyphosate, and 2.5-19-fold decreased K(m) for phosphoenolpyruvate. Such mutants will be instrumental for the structural and function study of the enzyme and for the generation of transgenic crops resistant to the herbicide.
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89
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Akyürek LM, Nallamshetty S, Aoki K, San H, Yang ZY, Nabel GJ, Nabel EG. Coexpression of guanylate kinase with thymidine kinase enhances prodrug cell killing in vitro and suppresses vascular smooth muscle cell proliferation in vivo. Mol Ther 2001; 3:779-86. [PMID: 11356082 DOI: 10.1006/mthe.2001.0315] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Herpes simplex virus-thymidine kinase (HSV-TK) phosphorylates the prodrugs ganciclovir (GCV) and acyclovir (ACV), leading to disruption of DNA synthesis and inhibition of cell proliferation. HSV-TK vectors have been successfully employed in cardiovascular and cancer gene therapy. Activation of GCV and ACV, after an initial phosphorylation step by the viral thymidine kinase, is carried out by guanylate kinase. We reasoned that coexpression of guanylate kinase (GK) with HSV-TK would augment phosphorylation of GCV or ACV, leading to increased cell killing. To test this hypothesis, a vector expressing TK with GK (TKciteGK) was developed and tested on vascular smooth muscle cells (vsmcs) in vitro and in vivo. Compared to HSV-TK vectors, killing of vascular cells transduced with TKciteGK and exposed to GCV was significantly increased (P = 0.03). The TKciteGK construct was evaluated with three promoters: CMV, EF1alpha, and SM22alpha. TKciteGK expression driven by a CMV promoter induced cell killing more effectively than SM22alpha or EF1alpha promoters in primary vsmcs. Based upon these in vitro findings, TKciteGK vectors with a CMV promoter were tested in two animal models of cardiovascular disease: balloon angioplasty and stent deployment in pig arteries. Following vascular injury, expression of CMV-TKciteGK with GCV significantly reduced vsmc proliferation and intimal lesion formation compared to control vectors with GCV. In the angioplasty model, there was an 80% reduction in intima-to-media area ratio (P = 0.0002). These findings were paralleled in a stent model with 66% reduction in intimal lesions (P = 0.006). Coexpression of GK with TK increases cell killing and permits administration of GCV at lower doses. These modifications in TKciteGK vectors and GCV showed enhanced efficacy at lower prodrug doses, leading to improved safety for cardiovascular gene therapy.
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90
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Li XB, Yi CD, Zhai WX, Yang ZY, Zhu LH. [A genetically modified japonica restorer line, C418-Xa21, and its hybrid rice with bacterial blight resistance]. SHENG WU GONG CHENG XUE BAO = CHINESE JOURNAL OF BIOTECHNOLOGY 2001; 17:380-4. [PMID: 11702691] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/22/2023]
Abstract
The cloned bacterial blight (BB) resistance gene Xa21 was transferred into C418, a major restorer line of japonica hybrid rice in China, using an Agrobacterium-mediated system. The integrated single copy of transgene displayed a 3:1 segregation ratio in T1 generation in PCR and resistance analyses. The transgenic homozygous C418-Xa21 lines were selected in T2 generation through PCR and resistance analyses. The selected transgenic restorer lines were then crossed with a commonly used sterile line, TijinA, to produce Xa21 transgenic hybrid rice. Molecular analysis revealed that the produced hybrid rice, named as Tiyou418-Xa21, inherited the transgene. Both C418-Xa21 and Tiyou418-Xa21 plants displayed high resistance with a broad spectrum to Xoo races and maintained their normal elite agronomic characters. We also observed that the resistance level of Tiyou418-Xa21 was obviously higher than that of C418-Xa21 which may be attributed to their differences in genetic background. The propagation of this BB resistant hybrid variety with the transgene Xa21 with extend hybrid rice production in north China.
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91
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Xia Y, Yang ZY, Hour MJ, Kuo SC, Xia P, Bastow KF, Nakanishi Y, Namrpoothiri P, Hackl T, Hamel E, Lee HK. Antitumor Agents. Part 204: Synthesis and Biological Evaluation of Substituted 2-Aryl Quinazolinones. Bioorg Med Chem Lett 2001; 11:1193-6. [PMID: 11354375 DOI: 10.1016/s0960-894x(01)00190-1] [Citation(s) in RCA: 136] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
A series of 2',3',4',6,7-substituted 2-aryl quinazolinones were synthesized and evaluated for biological activity. Among them, 17 displayed significant growth inhibitory action against a panel of tumor cell lines. Compound 17 was also a potent inhibitor of tubulin polymerization. Compounds 8-10 displayed selective activity against P-gp-expressing epidermoid carcinoma of the asopharynx.
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92
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Ye ZH, Yang ZY, Chan GY, Wong MH. Growth response of Sesbania rostrata and S. cannabina to sludge-amended lead/zinc mine tailings. A greenhouse study. ENVIRONMENT INTERNATIONAL 2001; 26:449-455. [PMID: 11392765 DOI: 10.1016/s0160-4120(01)00026-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Legumes are ideal for revegetation of metal-mined wastelands which lack nitrogen (N). A greenhouse study was conducted to investigate the feasibility of using Sesbania rostrata and S. cannabina for the reclamation of lead/zinc (Pb/Zn) mine tailings and to evaluate the effects of organic amendment using sewage sludge (0%, 25%, 50%, and 75%, v/v). The results showed that both species could continue to grow on the highly toxic tailings substrata for at least 80 days, although their growth suffered from adverse effects. That S. rostrata with stem and root nodules had better growth (biomass, growth rates, and biomass of nodules) than S. cannabina suggested that S. rostrata is a better choice as a pioneer species for revegetation of the mine tailings. Stem nodules had less obvious adverse effects imposed by tailings than root nodules. Application of sewage sludge increased contents of total carbon (C), N, phosphorus (P), and potassium (K), and reduced total Zn, Pb, Cd, and DTPA-extractable Pb and Cd in tailings substrata. These, in turn, reduced metal (Zn, Pb, and Cd) uptake and accumulation in plant tissues, and improved plant growth performance, including biomass, growth rates, stem nodulation. Fifty percent (v/v) of sludge application rate was the best loading rate for plant growth.
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93
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Shang ZB, Gao Q, Yang DA, Yang ZY. Spatial distribution analysis on climatic variables in northeast China. J Environ Sci (China) 2001; 13:247-251. [PMID: 11590751] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Information ecology is a new research area of modern ecology. Here describes the spatial distribution analysis methods of four sorts of climatic variables, i.e. temperature, precipitation, relative humidity and sunshine fraction in Northeast China. First, digital terrain models was built with large-scale maps and vector data. Then trend surface analysis and interpolation method were used to analyze the spatial distribution of these four kinds of climatic variables at three temporal scale: (1) monthly data; (2) mean monthly data of thirty years, and (3) mean annual data of thirty years. Ecological information system were used for graphics analysis on the spatial distribution of these climatic variables.
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Han J, Sheng LS, Yang ZY, Xiang BR, An DK. [High performance liquid chromatography/electrospray ionization mass spectrometric characterization of recombinant L-asparaginase II]. YAO XUE XUE BAO = ACTA PHARMACEUTICA SINICA 2001; 36:46-50. [PMID: 12579860] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
Abstract
AIM To characterize the primary structure of recombinant L-asparaginase II product. METHODS The molecular weight of the protein was measured by pneumatically-assisted electrospray ionization mass spectrometry with flow injection mode. Subsequently, tryptic peptide mapping was performed by high performance liquid chromatography on a C8 column with tandem UV and MS detection. An easy-to-use and simple denaturation process with trichloroacetic acid was conducted prior to tryptic digest so as to release the digest resistance from the protein structure. The amino acid sequences of the tryptic peptides were elucidated based on their in-source collision-induced dissociation spectra. RESULTS The measured molecular mass was different from the theoretical value. Three amino acid variations were unambiguously detected along the peptide backbone derived from the gene-encoding sequence. CONCLUSION This paper revealed that LC/ESI/MS had provided a promising and robust technique in primary structure analysis and quality control of DNA-derived recombinant protein pharmaceuticals.
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Chen Y, Xia P, Zhang Q, Zheng YH, Xia Y, Yang ZY. [Synthesis of droloxifene citrate and its new bioactivity]. YAO XUE XUE BAO = ACTA PHARMACEUTICA SINICA 2000; 35:902-5. [PMID: 12567911] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
Abstract
AIM To investigate a feasible synthetic procedure of droloxifene and study on its new bioactivities. METHODS AND RESULTS Droloxifene was synthesized using methoxybenzene and phenylacetic acid as starting materials, via Friedel-Crafts acylation, alkylation, demethylation, etherification, Grignard addition, elimination-dehydration, conversing configuration and forming citrate, totally 8 steps, overall yield 14.7% (9.2%). By pharmacological test, droloxifene citrate shows two new bioactivities: (1) obvious effect on reversing the MDR of K562/A02 cells and modulating mdrl, GST pi and TopoII alpha expression. (2) inducing apoptosis in cultured rat luteal cell. CONCLUSION The improved synthetic procedure is shorter than the reported method by two steps and has advantages of simple separation, purification and conversion of configuration; easily available starting materials and reagents; concise operation. Two new bioactivities on reversing MDR and inducing apoptosis of luteal cell offered a clue in new drugs research and widened clinic application of droloxifene.
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96
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Sullivan NJ, Sanchez A, Rollin PE, Yang ZY, Nabel GJ. Development of a preventive vaccine for Ebola virus infection in primates. Nature 2000; 408:605-9. [PMID: 11117750 DOI: 10.1038/35046108] [Citation(s) in RCA: 509] [Impact Index Per Article: 21.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Outbreaks of haemorrhagic fever caused by the Ebola virus are associated with high mortality rates that are a distinguishing feature of this human pathogen. The highest lethality is associated with the Zaire subtype, one of four strains identified to date. Its rapid progression allows little opportunity to develop natural immunity, and there is currently no effective anti-viral therapy. Therefore, vaccination offers a promising intervention to prevent infection and limit spread. Here we describe a highly effective vaccine strategy for Ebola virus infection in non-human primates. A combination of DNA immunization and boosting with adenoviral vectors that encode viral proteins generated cellular and humoral immunity in cynomolgus macaques. Challenge with a lethal dose of the highly pathogenic, wild-type, 1976 Mayinga strain of Ebola Zaire virus resulted in uniform infection in controls, who progressed to a moribund state and death in less than one week. In contrast, all vaccinated animals were asymptomatic for more than six months, with no detectable virus after the initial challenge. These findings demonstrate that it is possible to develop a preventive vaccine against Ebola virus infection in primates.
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Akyürek LM, Yang ZY, Aoki K, San H, Nabel GJ, Parmacek MS, Nabel EG. SM22alpha promoter targets gene expression to vascular smooth muscle cells in vitro and in vivo. Mol Med 2000; 6:983-91. [PMID: 11147575 PMCID: PMC1949920] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023] Open
Abstract
BACKGROUND Gene transfer into vascular smooth muscle cells (vsmcs) holds promise for studying the pathogenesis of arterial disorders. However, a potential limitation of vectors with heterologous promoters is organ toxicity resulting from unrestricted transgene expression. Vascular smooth muscle cell-specific gene expression could increase the safety of vectors for vascular diseases. MATERIALS AND METHODS To develop vectors that target gene expression to vsmcs, we constructed vectors encoding human placental alkaline phosphatase (hpAP) and chloramphenicol transferase (CAT) driven by a 441-bp region of the murine SM22alpha promoter (AdSM22alpha-hpAP). RESULTS Transfection of AdSM22alpha-hpAP into vascular and nonvascular cells resulted in the expression of alkaline phosphatase (AP) in primary arterial and venous smcs, but not in primary endothelial cells or National Institutes of Health (NIH) 3T3 cells. Expression of AP was observed on 32.5 +/- 1.4% of primary pig vsmcs-infected AdSM22alpha-hpAP at a multiplicity of infection (MOI) of 500; whereas, infection with AdCMV-hpAP resulted in 100 +/- 0.0% expression at a MOI of 250. In vitro, expression from the heterologous cytomegalovirus (CMV) promoter was approximately 10(3)-fold higher in vsmcs, compared with the SM22alpha promoter. Following introduction of AdSM22alpha-hpAP vectors into balloon-injured pig arteries, AP recombinant protein was detected in neointimal (2.23 +/- 1.14%) and medial (0.56 +/- 0.21%) smcs, but not in endothelial or adventitial cells. In contrast, AdCMV-hpAP vectors led to AP expression in intimal endothelial and smcs cells (39.14 +/- 10.09%) and medial smcs (2.84 +/- 1.05%). AP expression was not observed in endothelial or vsmcs following transfection with the control vector, adenoviral vector lacking E1 (AddeltaE1). CONCLUSIONS The SM22alpha promoter programs recombinant gene expression exclusively to vascular smcs in vitro and in vivo. Although expression levels are lower than with heterologous promoters, these vectors may provide a safe and effective tool for gene therapy of vascular diseases.
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98
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Cai ZB, Zhou M, Hu WX, Yang ZY. [Synthesis and antineoplastic activity of N,N'-disubstituted phenyl-3,6-dimethyl-1,4-dihydro-1,2,4,5-tetrazine-1,4-dicarboamide derivatives]. YAO XUE XUE BAO = ACTA PHARMACEUTICA SINICA 2000; 35:793-6. [PMID: 11372451] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/16/2023]
Abstract
AIM To search for antineoplastic drugs with fewer side effects and improved activities, using tetrazine derivatives with different substituted groups in their phenyl rings. METHODS The title compounds have been synthesized by reacting 3,6-dimethyl-1,6-dihydro-1,2,4,5-tetrazine with substituted phenyl isocyanates in the presence of p-dimethylamino pyridine as catalyst. RESULTS Eighteen new N,N'-disubstituted phenyl-3,6-dimethyl-1,4-dihydro-1,2,4,5-tetrazine-1,4-dicarboamides have been synthesized. Their structures have been confirmed by IR, 1HNMR and elemental analysis. The antineoplastic activities were screened. The structure-activity relationship has also been studied. CONCLUSION The meta-substituted tetrazine derivatives showed marked antitumor activities against P388 and A-549 when electronic effect constants and hydrophobic constants of their substitutents are in a certain range.
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Yang ZY, Duckers HJ, Sullivan NJ, Sanchez A, Nabel EG, Nabel GJ. Identification of the Ebola virus glycoprotein as the main viral determinant of vascular cell cytotoxicity and injury. Nat Med 2000; 6:886-9. [PMID: 10932225 DOI: 10.1038/78645] [Citation(s) in RCA: 273] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Here we defined the main viral determinant of Ebola virus pathogenicity; synthesis of the virion glycoprotein (GP) of Ebola virus Zaire induced cytotoxic effects in human endothelial cells in vitro and in vivo. This effect mapped to a serine-threonine-rich, mucin-like domain of this type I transmembrane glycoprotein, one of seven gene products of the virus. Gene transfer of GP into explanted human or porcine blood vessels caused massive endothelial cell loss within 48 hours that led to a substantial increase in vascular permeability. Deletion of the mucin-like region of GP abolished these effects without affecting protein expression or function. GP derived from the Reston strain of virus, which causes disease in nonhuman primates but not in man, did not disrupt the vasculature of human blood vessels. In contrast, the Zaire GP induced endothelial cell disruption and cytotoxicity in both nonhuman primate and human blood vessels, and the mucin domain was required for this effect. These findings indicate that GP, through its mucin domain, is the viral determinant of Ebola pathogenicity and likely contributes to hemorrhage during infection.
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Feng QF, Wang M, Wang LJ, Yang ZY, Zhang YG, Zhang DW, Yin WB. A study of postoperative radiotherapy in patients with non-small-cell lung cancer: a randomized trial. Int J Radiat Oncol Biol Phys 2000; 47:925-9. [PMID: 10863061 DOI: 10.1016/s0360-3016(00)00509-5] [Citation(s) in RCA: 132] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
PURPOSE To study the value of postoperative radiotherapy for non-small-cell lung cancer (NSCLC) with positive regional lymph metastases (NI or N2) after radical surgery. MATERIALS AND METHODS From February 1982 to October 1995, 366 patients with NSCLC and N1 or N2 disease were randomized into postoperative radiotherapy (S + R) (183 patients) and no further treatment (S alone) (182 patients). Postoperative radiotherapy (RT) was administrated 3-4 weeks after radical operation. Irradiated fields covered the bronchial stump, ipsilateral hilum, and most of the mediastinum. The midplane dose was 6000 cGy/30 fractions/6 weeks, with the spinal cord limited to 4000 cGy/20 fractions/4 weeks or less. One hundred thirty-four patients in S + R group and 162 patients in S alone group were evaluated. Clinical data were comparable in both arms, except for the numbers of N2 patients. RESULTS The 3-year and 5-year overall survival rates were 51.9% and 42.9% in the S + R group and 50.2% and 40.5% in the S alone Group (p = 0.56). The 3-year and 5-year disease-free survival rates were 50.7% +/- 4.7% and 42.9% +/- 5.2% in the S + R group vs. 44.4% +/- 4.3% and 38.2% +/- 4.5% in the S alone group (p = 0.28), respectively. In the patients with NI or T3-4 tumors, there was a trend toward improved survival in the S + R group, especially in the patients with T3-4N1M0. These patients demonstrated 20% improvement in overall survival (p = 0.092) and greater than 20% better disease-free survival (p = 0.057). Postoperative RT reduced local recurrence but had no impact on distant metastases. CONCLUSION Postoperative RT significantly reduced local relapses, but did not improve overall survival, due to a high frequency of distant metastases in this patient group.
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