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831.
Daria Petrenko Vladimir Chubarev Nikita Syzrantsev Nafeeza Ismail Vadim Merkulov Susanna Sologova Ekaterina Grigorevskikh Elena Smolyarchuk Renad Alyautdin 《Molecules (Basel, Switzerland)》2022,27(11)
The most common primary malignant brain tumors in adults are gliomas. Glioblastoma is the most prevalent and aggressive tumor subtype of glioma. Current standards for the treatment of glioblastoma include a combination of surgical, radiation, and drug therapy methods. The drug therapy currently includes temozolomide (TMZ), an alkylating agent, and bevacizumab, a recombinant monoclonal IgG1 antibody that selectively binds to and inhibits the biological activity of vascular endothelial growth factor. Supplementation of glioblastoma radiation therapy with TMZ increased patient survival from 12.1 to 14.6 months. The specificity of TMZ effect on brain tumors is largely determined by special aspects of its pharmacokinetics. TMZ is an orally bioavailable prodrug, which is well absorbed from the gastrointestinal tract and is converted to its active alkylating metabolite 5-(3-methyl triazen-1-yl)imidazole-4-carbozamide (MTIC) spontaneously in physiological condition that does not require hepatic involvement. MTIC produced in the plasma is not able to cross the BBB and is formed locally in the brain. A promising way to increase the effectiveness of TMZ chemotherapy for glioblastoma is to prevent its hydrolysis in peripheral tissues and thereby increase the drug concentration in the brain that nanoscale delivery systems can provide. The review discusses possible ways to increase the efficacy of TMZ using nanocarriers. 相似文献
832.
Vladislav V. Oreshko Kseniya S. Kovaleva Ekaterina D. Mordvinova Olga I. Yarovaya Yuri V. Gatilov Dmitry N. Shcherbakov Nikolai I. Bormotov Olga A. Serova Larisa N. Shishkina Nariman F. Salakhutdinov 《Molecules (Basel, Switzerland)》2022,27(15)
A set of heterocyclic products was synthesized from natural (+)-camphor and semi-synthetic (−)-camphor. Then, 2-Imino-4-thiazolidinones and 2,3-dihydrothiazoles were obtained using a three-step procedure. For the synthesized compounds, their antiviral activity against the vaccinia virus and Marburg virus was studied. New promising agents active against both viruses were found among the tested compounds. 相似文献
833.
Alexei R. Khokhlov Felix F. Ternovsky Ekaterina A. Zheligovskaya 《Macromolecular theory and simulations》1993,2(2):151-168
The exact solution of the problem of adsorption of a long ideal polymer chain with variable degree of stiffness on a plane surface is presented. It is shown that the adsorption of stiff polymer chains is a second-order phase transition; in the adsorbed state “train” (i.e. adsorbed) sections are relatively longer and loop sections relatively shorter than for flexible chains. This effect is very pronounced: already for moderately stiff chains the number of Kuhn segment lengths in one “train” section at the temperature T = Tcr/2 (Tcr is the critical temperature for adsorption transition) can reach several thousands, and deviation from the surface occurs only in the form of small “hairpins”. The maximum length of the chain, which at the given conditions would flatten completely on the surface, is estimated. 相似文献
834.
Dr. Vyacheslav Sushev Dr. Yulia Panova Dr. Alexandra Khristolyubova Dr. Natalia Zolotareva Matvey Grishin Dr. Roman Rumyantcev Ekaterina Kozlova Prof. Dr. Georgy Fukin Prof. Dr. Alexander Kornev 《欧洲无机化学杂志》2023,26(23):e202300252
A number of two-deck dicationic 3a,6a-diaza-1,4-diphosphapentalenes (DDP)2X2 (X=halogen or complex ion) have been characterized. Interdeck distances P(1)⋅⋅⋅P(3) and P(2)⋅⋅⋅P(4) in crystal structures, as a rule, significantly exceed the sum of covalent radii, however they are still within the sum of van der Waals radii. The 31P NMR data indicate that phosphorus atoms are equivalent in solution even at low temperatures (233 K). Based on DFT calculations, the formation of two equivalent P−P covalent bonds (<2.4 Å) is energetically unfavorable, despite the absence of steric barriers. The total energy of the model dication as a function of the P⋅⋅⋅P separation has a minimum at the P−P distance of 2.85 Å. This distance corresponds to the highest aromaticity index in the interdeck space (NICS(1.0)=−20.72). The energy of interdeck interactions is estimated at 10–15 kcal/mol. 相似文献