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51.
Fluorescence imaging and phototoxicity effects of new formulation of chlorin e6-polyvinylpyrrolidone
Chin WW Lau WK Heng PW Bhuvaneswari R Olivo M 《Journal of photochemistry and photobiology. B, Biology》2006,84(2):103-110
Evaluations of the efficiency of a new formulation of chlorin consisting of a complex of trisodium salt chlorin e6 (Ce6) and polyvinylpyrrolidone (PVP) in photodynamic therapy (PDT) and fluorescence diagnosis was performed on poorly differentiated human bladder carcinoma murine model with the following specific aims: (i) to qualitatively evaluate the fluorescence accumulation in human bladder tumor, (ii) to determine fluorescence distribution of Ce6-PVP using the tissue extraction technique and fluorescence imaging technique, (iii) to compare the fluorescence distribution of Ce6, Ce6-PVP and Photofrin in skin of nude mice, and (iv) to investigate phototoxicity caused by different parameters (drug-light interval, drug dose, irradiation fluence rate and total light fluence) in PDT. The fluorescence of the Ce6-PVP formulation was determined either by fluorescence imaging measurements or by chemical extraction from the tissues displaying similar trends of distribution. Our results demonstrated that the Ce6-PVP formulation possesses less in vivo phototoxic effect compared to Ce6 alone. The phototoxicity revealed a strong dependence on the drug and light dosimetry as well as on the drug-light interval. In PDT, the Ce6-PVP compound was most toxic at the 1h drug-light interval at 200J/cm(2), while Ce6 alone was most toxic at a light dose of more that 50J/cm(2) at the 1 and 3h drug-light interval. We also confirmed that Ce6-PVP has a faster clearance compared to Ce6 alone or Photofrin. This eliminates the need for long-term photosensitivity precautions. In conclusion, the Ce6-PVP formulation seems to be a promising photosensitizer for fluorescence imaging as well as for photodynamic treatment. 相似文献
52.
Enzyme‐Mediated Site‐Specific Bioconjugation of Metal Complexes to Proteins: Sortase‐Mediated Coupling of Copper‐64 to a Single‐Chain Antibody 下载免费PDF全文
Dr. Brett M. Paterson Dr. Karen Alt Charmaine M. Jeffery Prof. Roger I. Price Shweta Jagdale Dr. Sheena Rigby Dr. Charlotte C. Williams Prof. Karlheinz Peter Prof. Christoph E. Hagemeyer Assoc. Prof. Paul S. Donnelly 《Angewandte Chemie (International ed. in English)》2014,53(24):6115-6119
The enzyme‐mediated site‐specific bioconjugation of a radioactive metal complex to a single‐chain antibody using the transpeptidase sortase A is reported. Cage amine sarcophagine ligands that were designed to function as substrates for the sortase A mediated bioconjugation to antibodies were synthesized and enzymatically conjugated to a single‐chain variable fragment. The antibody fragment scFvanti‐LIBS targets ligand‐induced binding sites (LIBS) on the glycoprotein receptor GPIIb/IIIa, which is present on activated platelets. The immunoconjugates were radiolabeled with the positron‐emitting isotope 64Cu. The new radiolabeled conjugates were shown to bind selectively to activated platelets. The diagnostic potential of the most promising conjugate was demonstrated in an in vivo model of carotid artery thrombosis using positron emission tomography. This approach gives homogeneous products through site‐specific enzyme‐mediated conjugation and should be broadly applicable to other metal complexes and proteins. 相似文献
53.
John W. Goodby Isabel M. Saez Stephen J. Cowling Julita S. Gasowska Robert A. MacDonald Susan Sia 《Liquid crystals》2013,40(6-7):567-605
In this article we investigate the complexity of the molecular architectures of liquid crystals based on rod-like mesogens. Starting from simple monomeric systems founded on fluoroterphenyls, we first examine the effects of aromatic core structure on mesophase formation from the viewpoint of allowable polar interactions, and then we model these interactions as a function of terminal aliphatic chain length. By incorporating a functional group at the end of one, or both, of the aliphatic chains we study the effects caused by intermolecular interfacial interactions in lamellar phases, and in particular the formation of synclinic or anticlinic modifications. We then develop these ideas with respect to dimers, trimers, tetramers, etc. We show, for dendritic systems, that at a certain level of molecular complexity the local mesogenic interactions become irrelevant, and it is gross molecular shape that determines mesophase stability. The outcome of these studies is to link the complexity of the molecular interactions at the nanoscale level, which lead to the creation of the various liquid-crystalline polymorphs, with the formation of mesophases that are dependent on complex shape dependencies for mesoscopic supermolecular architectures. 相似文献
54.
Xiu Jie Liu Xin He Cheng Ling Shi Jie Meng Ying Lu Shao Hong Qiang Si Tao Hu 《中国化学快报》2011,22(10):1139-1142
On the propose of searching for the SAR and obtaining novel antiplatelet aggregating drugs,we have described the synthesis procedure and the activities in vitro on antiplatelet aggregation of two series of derivatives,which contain both 18 N.N’-di(2- substitutedphenyl)-4-methoxyisophthalamides(2a-2r) of the 2 series and nine N,N’-di(2-substitutedphenyl)-4-methoxybenzene- 1,3-disulfonamides(3a-3i) of the 3 series.The results showed that three compounds 2e,2i and 3g emerged as significant activities of antiplatelet aggregation,superior to two reference drugs picotamide and aspirin,and eight compounds 2j,2k,21,2o,2p,2q,2r and 3i merely superior to picotamide.The preliminary SAR shows that it is favorable for the 2 series to increase the activities via the steric hindrance substituents attached to the two side chain benzene rings at 2-positions.And the arylamides of the 2 series have better the activity values than the arylsulfonamides of the 3 series respective except for 3b and 3g.On the contrary,electrostatic factors would not contribute evidently to the activities of the two series.The structures of 15 compounds newly synthesized have been established by MS and ~1H NMR and been first reported in this paper. 相似文献
55.
Shubhajit Paul Susithra Selvam Paul Wan Sia Heng Lai Wah Chan 《Journal of fluorescence》2013,23(5):1065-1076
Molecular aggregation in aqueous media is one of the factors which largely affects the efficacy of photosensitizers in photodynamic therapy. Chlorin e6 (Ce6) in aggregated form is known to exhibit markedly reduced therapeutic effects. In the present study, aggregate to monomer conversion of Ce6 was investigated as a function of pH and polyvinylpyrrolidone (PVP) concentration by simple absorption and fluorescence spectroscopic techniques. Aggregation of Ce6 was observed in the pH range of 2 to 6 as indicated by changes in UV–vis absorption spectra, fluorescence emission spectra and relative quantum yield. Novel chemometric approach was considered for determining the relative monomerization efficiency of different grades of PVP. The chemometric analysis and binding constant study both strongly revealed that the Ce6-PVP complex was more efficiently formed with PVP of the lowest molecular weight (K17). Thermodynamic parameters, such as the heat of entropy and enthalpy, showed that complex formation was largely attributed to hydrophobic interaction between Ce6 and PVP. This was found to be consistent with the results obtained from molecular simulation study. 相似文献
56.
Rotimi C Leppert M Matsuda I Zeng C Zhang H Adebamowo C Ajayi I Aniagwu T Dixon M Fukushima Y Macer D Marshall P Nkwodimmah C Peiffer A Royal C Suda E Zhao H Wang VO McEwen J;International HapMap Consortium 《Community genetics》2007,10(3):186-198
The International HapMap Consortium has developed the HapMap, a resource that describes the common patterns of human genetic variation (haplotypes). Processes of community/public consultation and individual informed consent were implemented in each locality where samples were collected to understand and attempt to address both individual and group concerns. Perceptions about the research varied, but we detected no critical opposition to the research. Incorporating community input and responding to concerns raised was challenging. However, the experience suggests that approaching genetic variation research in a spirit of openness can help investigators better appreciate the views of the communities whose samples they seek to study and help communities become more engaged in the science. 相似文献
57.
Artuso M Blusk S Butt J Khalil S Li J Menaa N Mountain R Nisar S Randrianarivony K Sia R Skwarnicki T Stone S Wang JC Bonvicini G Cinabro D Dubrovin M Lincoln A Asner DM Edwards KW Naik P Briere RA Ferguson T Tatishvili G Vogel H Watkins ME Rosner JL Adam NE Alexander JP Cassel DG Duboscq JE Ehrlich R Fields L Gibbons L Gray R Gray SW Hartill DL Heltsley BK Hertz D Jones CD Kandaswamy J Kreinick DL Kuznetsov VE Mahlke-Krüger H Mohapatra D Onyisi PU Patterson JR Peterson D Pivarski J Riley D 《Physical review letters》2007,99(7):071802
We measure the decay constant f(Ds+) using the D(s+)-->l+ nu channel, where the l+ designates either a mu+ or a tau+, when the tau+ -->pi+ nu. Using both measurements we find f(Ds+)=274+/-13+/-7 MeV. Combining with our previous determination of f(D+), we compute the ratio f(Ds+)/f(D+)=1.23+/-0.11+/-0.04. We compare with theoretical estimates. 相似文献
58.
Coan TE Gao YS Liu F Artuso M Blusk S Butt J Li J Menaa N Mountain R Nisar S Randrianarivony K Redjimi R Sia R Skwarnicki T Stone S Wang JC Zhang K Csorna SE Bonvicini G Cinabro D Dubrovin M Lincoln A Asner DM Edwards KW Briere RA Brock I Chen J Ferguson T Tatishvili G Vogel H Watkins ME Rosner JL Adam NE Alexander JP Berkelman K Cassel DG Duboscq JE Ecklund KM Ehrlich R Fields L Galik RS Gibbons L Gray R Gray SW Hartill DL Heltsley BK Hertz D Jones CD Kandaswamy J Kreinick DL Kuznetsov VE 《Physical review letters》2006,96(16):162003
Using data collected with the CLEO detector operating at the CESR e+e- collider at sqrt[s]=3.97-4.26 GeV, we investigate 15 charmonium decay modes of the psi(4040), psi(4160), and Y(4260) resonances. We confirm, at 11 sigma significance, the BABAR Y(4260)-->pi+pi- J/psi discovery, make the first observation of Y(4260)--> pi(0)pi(0) J/psi (5.1 sigma), and find the first evidence for Y(4260)-->K+K- J/psi(3.7 sigma). We measure e+e- cross sections at sqrt[s]=4.26 GeV as sigma(pi+pi- J/psi)=58(+12)(-10)+/-4 pb, sigma(pi(0)pi(0) J/psi)=23(+12)(-8)+/-1 pb, and sigma(K+K- J/psi)=9(+9)(-5)+/-1 pb, in which the uncertainties are statistical and systematic, respectively. Upper limits are placed on other decay rates from all three resonances. 相似文献
59.
Besson D Pedlar TK Cronin-Hennessy D Gao KY Gong DT Hietala J Kubota Y Klein T Lang BW Poling R Scott AW Smith A Zweber P Dobbs S Metreveli Z Seth KK Tomaradze A Ernst J Severini H Dytman SA Love W Savinov V Aquines O Li Z Lopez A Mehrabyan S Mendez H Ramirez J Huang GS Miller DH Pavlunin V Sanghi B Shipsey IP Xin B Adams GS Anderson M Cummings JP Danko I Napolitano J He Q Insler J Muramatsu H Park CS Thorndike EH Yang F Coan TE Gao YS Liu F Artuso M Blusk S Butt J Horwitz N Li J Menaa N 《Physical review letters》2007,98(5):052002
Using data collected with the CLEO III detector at the CESR e+e- collider, we report on a first observation of the decay Upsilon(3S)-->tau+tau-, and precisely measure the ratio of branching fractions of Upsilon(nS), n=1, 2, 3, to tau+tau- and mu+mu- final states, finding agreement with expectations from lepton universality. We derive absolute branching fractions for these decays, and also set a limit on the influence of a low mass CP-odd Higgs boson in the decay of the Upsilon(1S). 相似文献
60.
Vipin Agrawal Kristin Holzworth Wiroj Nantasetphong Alireza V. Amirkhizi Jay Oswald Sia Nemat‐Nasser 《Journal of Polymer Science.Polymer Physics》2016,54(8):797-810
To explore the relationship between microscopic structure and viscoelastic properties of polyurea, a coarse‐grained (CG) model is developed by a structure matching method and validated against experiments conducted on a controlled, benchmark material. Using the Green‐Kubo method, the relaxation function is computed from the autocorrelation of the stress tensor, sampled over equilibrium MD simulations, and mapped to a real time scale established by matching self‐diffusion rates of atomistic and CG models. Master curves computed from the predicted stress relaxation function are then compared with dynamic mechanical analysis experiments mapped to a wide frequency range by time–temperature superposition, as well as measurements of ultrasonic shear wave propagation. Computational simulations from monodisperse and polydisperse configurations, representative of the benchmark polyurea, show excellent agreement with the experimental measurements over a multidecade range of loading frequency. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2016 , 54, 797–810 相似文献