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21.
Lei Zhao Tien Duy Vo Marcel Kaiser Prof. Dr. Helge B. Bode 《Chembiochem : a European journal of chemical biology》2020,21(9):1288-1292
A new cyclic lipopeptide, phototemtide A ( 1 ), was isolated from Escherichia coli expressing the biosynthetic gene cluster pttABC from Photorhabdus temperata Meg1. The structure of 1 was elucidated by HR-ESI-MS and NMR experiments. The absolute configurations of amino acids and 3-hydroxyoctanoic acid in 1 were determined by using the advanced Marfey's method and comparison after total synthesis of 1 , respectively. Additionally, three new minor derivatives, phototemtides B–D ( 2 – 4 ), were identified by detailed HPLC–MS analysis. Phototemtide A ( 1 ) showed weak antiprotozoal activity against Plasmodium falciparum, with an IC50 value of 9.8 μm . The biosynthesis of phototemtides A–D ( 1 – 4 ) was also proposed. 相似文献
22.
Diem-Huong Nguyen Tran Thi Hiep Nguyen Thanh Nguyet Nguyen Vo Linh Phuong Tran Pham Do Minh Hoang Vo Cuu Khoa Nguyen Long Giang Bach Dai Hai Nguyen 《应用聚合物科学杂志》2019,136(20):47544
Curcumin (CUR) is a natural active ingredient that attracted much attention for its chemotherapeutic activity against tumors without causing toxicity in healthy cells. However, it has certain limitations for being used in chemotherapy such as low aqueous solubility and hydrolytic instability in the physiological environment. In this study, self-assembled poly(ethylene glycol) methyl ether-grafted gelatin (Gel-mPEG) nanogels were fabricated as delivery systems to improve the applicability of CUR in cancer treatment. CUR-loaded Gel-mPEG nanogels exhibited desired size range, relatively colloidal stability, and provided enhanced CUR stability in aqueous solutions. Especially, they showed significant high CUR loading capacity and better anticancer activity than free CUR as compared to previously reported CUR-loaded nanogels according to the best of our knowledge. Moreover, the in vitro release of CUR from the nanogels was controlled and prolonged up to 96 h. These results demonstrated that Gel-mPEG nanogels are the promising modality for the efficient delivery of CUR in cancer treatment. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47544. 相似文献
23.
Duc Quy Vo Eun Woo Shin Jae-Seong Kim Sunwook Kim 《Korean Journal of Chemical Engineering》2012,29(1):120-124
A significant change in the UV-vis absorption of TiO2 nanorods (NRs) was induced by changing electrondonating stabilizer from oleic acid (OA) to acrylic acid (AcA). When TiO2 NRs with an average size of 2.5 nm in diameter and 30 nm in length were dispersed in an aqueous AcA solution, a red shift
in the optical absorption (0.73 eV at the band edge and 0.55 eV at the onset) was observed. The red shift was attributed to
an increase in the electron density inside the TiO2 NRs. The applicability of the AcA-exchanged TiO2 NRs for the photocatalyst as well as a UV sensor was evaluated. The AcA-exchanged TiO2 NRs showed significant photocatalytic activity on the degradation of toluene in the visible light region. Moreover, thin
film of the AcA-exchanged TiO2 NRs on a quartz plate was tested as a UV sensor and it exhibited a good response to a wide range of the UV light. 相似文献
24.
Prof. Dr. Andreas Fink Prof. Dr. Natalia Kliewer Prof. Dr. Dirk Mattfeld Prof. Dr. Lars Mönch Prof. Dr. Franz Rothlauf Prof. Dr. Guido Schryen Prof. Dr. Leena Suhl Prof. Dr. Stefan Voß 《WIRTSCHAFTSINFORMATIK》2014,56(1):21-29
In this paper, we sketch some of the challenges that should be addressed in future research efforts for model-based decision support in manufacturing and service networks. This includes integration issues, taking into account the autonomy of the decision-making entities in face of information asymmetry, the modeling of preferences of the decision-makers, efficiently determining robust solutions, i.e. solutions that are insensitive with respect to changes in the problem data, and a reduction of the time needed for model building and usage. The problem solution cycle includes problem analysis, the design of appropriate algorithms and their performance assessment. We are interested in a prototypical integration of the proposed methods within application systems, which can be followed up with field tests of the extended application systems. We argue that the described research agenda requires the interdisciplinary collaboration of business and information systems engineering researchers with colleagues from management science, computer science, and operations research. In addition, we present some exemplifying, illustrative examples of relevant research results. 相似文献
25.
Trung Q. Duong Lei Shu Min Chen Vo Nguyen Quoc Bao Dac‐Binh Ha 《Wireless Communications and Mobile Computing》2015,15(3):500-509
Cooperative spatial multiplexing (CSM) system has played an important role in wireless networks by offering a substantial improvement in multiplexing gain compared with its cooperative diversity counterpart. However, there is a limited number of research works that consider the performance of CSM systems. As such, in this paper, we have derived exact performance of CSM with amplify‐and‐forward and decode‐and‐forward relays in terms of outage capacity and ergodic capacity. We have shown that CSM systems yield a unity diversity order regardless of the number of antennas at the destination and the number of relays in the networks, which is the direct result of diversity and multiplexing gain trade‐off. Our analytical expressions are corroborated by Monte‐Carlo simulations. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
26.
Nga T. N. Vo Lei Huang Henrique Lemos Andrew Mellor Katarina Novakovic 《应用聚合物科学杂志》2020,137(41):49259
In the development of pH-responsive chitosan-based hydrogels, achieving reproducible porosity and swelling behavior is essential for the design of hydrogel networks. Herein, we enhance the level of control in hydrogel microarchitecture by incorporating poly(ethylene glycol) (PEG) into the chitosan–genipin matrix. Hydrogels, varied in composition, were synthesized under mild conditions (37°C, 1 atm, 24 hr), yielding microporous structures with a pore diameter ranging from 11 to 57 μm and an average cross-sectional porosity of approximately 40–64%. Compared to chitosan–genipin hydrogels without PEG, presence of PEG in concentrations up to 1.9 mM generated the same effect as would increase in genipin content, yielding structures with a smaller pore diameter, a lower swelling degree in pH 2 buffer and a higher elastic modulus. Considering cost effectiveness and scale-up, reducing genipin content by the addition of PEG is favorable. Importantly, hydrogel samples containing higher concentrations of PEG (2.9 mM and above) showed a sudden increase in the swelling degree accompanied with a decrease in the elastic modulus. Findings showcase the potential variation in the composition of these hydrogels has in yielding scaffolds with significantly different physico-chemical behaviors. 相似文献
27.
28.
Natural bioactive peptides have been known as ingredients in nutraceuticals and pharmaceuticals. In this study, the potential anti-inflammatory peptides were purified from enzymatic hydrolysate of the edible microalgae Spirulina maxima using gastrointestinal endopeptidases (trypsin, α-chymotrypsin, and pepsin). Purification of the hydrolysate resulted in two peptides with amino acid sequences of LDAVNR (P1, 686 Da) and MMLDF (P2, 655 Da). It was found that peptides P1 and P2 exhibited significant inhibition on the release and production of histamine from antigen-stimulated RBL-2H3 mast cells. Moreover, the suppressive effect of P1 and P2 on production as well as expression of interleukin-8 in histamine-stimulated EA.hy926 endothelial cells was determined. Notably, the production of intracellular reactive oxygen species from mast cells and endothelial cells was decreased in the presence of P1 or P2. Collectively, the peptides P1 and P2 from S. maxima could be used as functional ingredients with potent anti-inflammatory benefits. 相似文献
29.
30.
A Bhandari DG Jones JR Schullek K Vo CA Schunk LL Tamanaha D Chen Z Yuan MC Needels MA Gallop 《Canadian Metallurgical Quarterly》1998,8(17):2303-2308
Phosphomannose Isomerase (PMI) has been shown by genetic methods to be an essential enzyme in fungal cell wall biosynthesis. The PMI inhibitor AF14049 was discovered as an unanticipated side product from high-throughput library screening against the enzyme from C, albicans. Solid-phase synthetic methods were developed and a series of libraries and discrete analogs synthesized to explore SAR around AF14049. 相似文献