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1.
Shunqing Zhang Dr. Ravindra R. Cheruku Dr. Mykhaylo Dukh Walter Tabaczynski Dr. Nayan J. Patel Dr. William H. White III Joseph R. Missert Dr. Joseph A. Spernyak Dr. Ravindra K. Pandey 《ChemMedChem》2020,15(21):2058-2070
3-(1’-Hexyloxyethyl)-3-devinyl-pyropheophorbide-a (HPPH or Photochlor), a tumor-avid chlorophyll-a derivative currently undergoing human clinical trials, was conjugated at various peripheral positions (position-17 or 20) of HPPH with either Gd(III)-aminobenzyl-DTPA (Gd(III) DTPA) or Gd(III)-aminoethylamido-DOTA (Gd(III) DOTA). The corresponding conjugates were evaluated for in vitro PDT efficacy, T1, T2 relaxivities, in vivo fluorescence, and MR imaging under similar treatment parameters. Among these analogs, the water-soluble Gd(III)-aminoethylamido-DOTA linked at position-17 of HPPH, i. e., HPPH-17-Gd(III) DOTA, demonstrated strong potential for tumor imaging by both MR and fluorescence, while maintaining the PDT efficacy in BALB/c mice bearing Colon-26 tumors (7/10 mice were tumor free on day 60). In contrast to Gd(III) DTPA (Magnevist) and Gd(III) DOTA (Dotarem), the HPPH-Gd(III) DOTA retains in the tumor for a long period of time (24 to 48 h) and provides an option of fluorescence-guided cancer therapy. Thus, a single agent can be used for cancer-imaging and therapy. However, further detailed pharmacokinetic, pharmacodynamic, and toxicological studies of the conjugate are required before initiating Phase I human clinical trials. 相似文献
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Tsoi Ip Qien Li Dr. Nick Brooks Dr. Yuval Elani 《Chembiochem : a European journal of chemical biology》2021,22(13):2275-2281
Efforts to manufacture artificial cells that replicate the architectures, processes and behaviours of biological cells are rapidly increasing. Perhaps the most commonly reconstructed cellular structure is the membrane, through the use of unilamellar vesicles as models. However, many cellular membranes, including bacterial double membranes, nuclear envelopes, and organelle membranes, are multilamellar. Due to a lack of technologies available for their controlled construction, multilayered membranes are not part of the repertoire of cell-mimetic motifs used in bottom-up synthetic biology. To address this, we developed emulsion-based technologies that allow cell-sized multilayered vesicles to be produced layer-by-layer, with compositional control over each layer, thus enabling studies that would otherwise remain inaccessible. We discovered that bending rigidities scale with the number of layers and demonstrate inter-bilayer registration between coexisting liquid–liquid domains. These technologies will contribute to the exploitation of multilayered membrane structures, paving the way for incorporating protein complexes that span multiple bilayers. 相似文献
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Sang Moon Lee Nong Xu John R. Grace Anwu Li C. Jim Lim Sung Su Kim Farzam Fotovat Achim Schaadt Robin J. White 《Journal of the European Ceramic Society》2018,38(1):211-219
NaA zeolite membranes were synthesised in the secondary growth hydrothermal method based on the seeding of the inner surface of a ceramic α-alumina tube. The impacts of crystallisation time and zeolite precursor concentration (in H2O) were investigated. The structure and stability of the prepared NaA zeolite membranes were also investigated with operating temperatures, times and pressures. The results indicate that the optimal synthesis gel molar composition was 3Na2O: 2SiO2: Al2O3: 200H2O. This led to cubic-shaped NaA zeolite which showed good stability. The optimal NaA zeolite membrane had H2O and CH3OH fluxes of 2.77 and 0.19 kg/m2h, with H2O/H2 and CH3OH/H2 separation factors of ∞ and 0.09 at a temperature of 30 °C. The NaA zeolite membrane had high thermal stability, but poor separation performance at high temperature (240 °C). The results suggested that the H2 permeation flux is significantly influenced by preferential adsorption of vapour in the NaA zeolite membrane. 相似文献
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John S. White 《Rocks & Minerals》2018,93(6):574-575