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201.
smail
zdemir Bekir etinkaya Serpil Demir Engin etinkaya Nevin Gürbüz Metin iek 《应用有机金属化学》2004,18(1):15-18
New [RuCl2(imidazoline)(arene)] complexes have been prepared. The complexes were characterized by conventional spectroscopic methods and elemental analyses. Upon reaction with 1,1‐diphenylprop‐2‐ynol they generate catalyst precursors that can perform the cycloisomerization of diallyltosylamide into N‐tosyl‐α‐methylenepyrrolidine. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
202.
In the present note, by use of the hyperbolic tangent method, a progressive wave solution to the Korteweg–de Vries–Burgers (KdVB) equation is presented. The solution we introduced here is less restrictive and comprises some solutions existing in the current literature (see [Wave Motion 11 (1989) 559; Wave Motion 14 (1991) 369]). 相似文献
203.
A Bifunctional Photosensitizer for Enhanced Fractional Photodynamic Therapy: Singlet Oxygen Generation in the Presence and Absence of Light
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Dr. Ilke Simsek Turan Deniz Yildiz Abdurrahman Turksoy Dr. Gurcan Gunaydin Prof. Dr. Engin U. Akkaya 《Angewandte Chemie (International ed. in English)》2016,55(8):2875-2878
The photosensitized generation of singlet oxygen within tumor tissues during photodynamic therapy (PDT) is self‐limiting, as the already low oxygen concentrations within tumors is further diminished during the process. In certain applications, to minimize photoinduced hypoxia the light is introduced intermittently (fractional PDT) to allow time for the replenishment of cellular oxygen. This condition extends the time required for effective therapy. Herein, we demonstrated that a photosensitizer with an additional 2‐pyridone module for trapping singlet oxygen would be useful in fractional PDT. Thus, in the light cycle, the endoperoxide of 2‐pyridone is generated along with singlet oxygen. In the dark cycle, the endoperoxide undergoes thermal cycloreversion to produce singlet oxygen, regenerating the 2‐pyridone module. As a result, the photodynamic process can continue in the dark as well as in the light cycles. Cell‐culture studies validated this working principle in vitro. 相似文献
204.
Intracellular Modulation of Excited‐State Dynamics in a Chromophore Dyad: Differential Enhancement of Photocytotoxicity Targeting Cancer Cells
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Dr. Safacan Kolemen Dr. Murat Işık Gyoung Mi Kim Dabin Kim Hao Geng Muhammed Buyuktemiz Tugce Karatas Prof. Xian‐Fu Zhang Prof. Yavuz Dede Prof. Juyoung Yoon Prof. Engin U. Akkaya 《Angewandte Chemie (International ed. in English)》2015,54(18):5340-5344
The photosensitized generation of reactive oxygen species, and particularly of singlet oxygen [O2(a1Δg)], is the essence of photodynamic action exploited in photodynamic therapy. The ability to switch singlet oxygen generation on/off would be highly valuable, especially when it is linked to a cancer‐related cellular parameter. Building on recent findings related to intersystem crossing efficiency, we designed a dimeric BODIPY dye with reduced symmetry, which is ineffective as a photosensitizer unless it is activated by a reaction with intracellular glutathione (GSH). The reaction alters the properties of both the ground and excited states, consequently enabling the efficient generation of singlet oxygen. Remarkably, the designed photosensitizer can discriminate between different concentrations of GSH in normal and cancer cells and thus remains inefficient as a photosensitizer inside a normal cell while being transformed into a lethal singlet oxygen source in cancer cells. This is the first demonstration of such a difference in the intracellular activity of a photosensitizer. 相似文献
205.
The method presented in Part I is extended to cover the damped and transient behavior of nonlinear systems described by equations of the form uss?uyy?εf(u,uy, uyys,…,s) = 0. The method is presented by application to the equation uss?uyy?εuyys?εu2yuyy= 0. Similar to the undamped case it is again shown that the PDE requires an infinite number of periodicity conditions to correctly characterize the resonant region. However, damping eliminates some of the branches of the amplitude-frequency spectrum of the undamped case. In fact, for ε = 0.25 all but the outermost branch disappear. A method of multiple time scales is presented for the study of the transient behavior and the stability of the branches for steady vibrations. The stability analysis yields an interior stable point in the amplitude-frequency spectrum which has no analog in the Duffing equation. Finally via the multiple scale procedure in the spirit of the early work of Zabusky and Kruskal one obtains forced Burgers and Korteweg-de Vries equations on a finite interval. 相似文献
206.
Ayman Chmayssem Lauriane Petit Nicolas Verplanck Véronique Mourier Séverine Vignoud Nihal Engin Vrana Pascal Mailley 《Electroanalysis》2022,34(7):1201-1211
Biocompatibility testing is usually performed through staining and imaging of cell lines. We propose here to monitor cytotoxicity through real-time measurement of metabolites specifically issued from cell stress behaviour using a multiparametric electrochemical (bio)sensing platform. However, the composition of culture media varies widely according to the requirements of the utilized cell lines. This matter may have significant effects on the sensor's sensitivity. With this mind, the sensitivity of four electrochemical (bio)sensors (pH, hydrogen peroxide, nitric oxide/nitrite (NO and its by-product) and lactate) is investigated in different cell culture media. The main culture media studied were Minimum Essential Medium Eagle (MEM), Dulbecco's Modified Eagle Medium (DMEM), Williams’ Medium E and RPMI 1640 medium that were the recommended culture media for the cell types to be monitored. This work shows the impact of the different cell culture media on the performances of the different sensors (limit of detection, sensitivity, selectivity, response time and dynamic range). More particularly, FBS strongly impacts the response of the amperometric (bio)sensors. Then, cellular viability testing was effected within optimized medium (FBS content) for electrochemical sensor read-outs in the case of short-term cultures (one day) devoted to cytotoxicity testing. Real-time electrochemical monitoring provides important additional information about cell behaviour during biocompatibility testing that might be further implemented in different settings including pharmaceutical efficacy and biomaterials applications. 相似文献
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209.
Süheyla
zbey Nuray Ulusoy Engin Kendi 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(2):222-224
In the title compounds, C15H12N4OS, (I), and C14H10N4OS, (II), the thiadiazine ring adopts a skew‐boat conformation, while the triazole and furyl rings are essentially planar. The phenyl group is twisted by 33.5 (2) and 47.9 (1)° out of the triazole‐ring plane in (I) and (II), respectively. 相似文献
210.