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排序方式: 共有819条查询结果,搜索用时 31 毫秒
811.
Ekaterina V. Ilgisonis Raisa Shalina Nigyar Kasum-Zade Kristina G. Burkova Oxana P. Trifonova Dmitry L. Maslov Anna L. Kaysheva Sergey S. Markin 《Molecules (Basel, Switzerland)》2022,27(8)
We sought to identify the characteristic metabolite profile of blood plasma samples obtained from patients with preeclampsia. Direct high-resolution mass spectrometry was used to analyze samples from 79 pregnant women, 34 of whom had preeclampsia. We performed a comparative analysis of the metabolite profiles and found that they differed between pregnant women with and without preeclampsia. Lipids and sugars were identified as components of the metabolite profile that are likely to be associated with the development of preeclampsia. While PE was established only in the third trimester, a set of metabolites specific for the third trimester, including 2-(acetylamino)-1,5-anhydro-2-deoxy-4-O-b-D-galactopyranosyl-D-arabino-Hex-1-enitol, N-Acetyl-D-glucosaminyldiphosphodolichol, Cer(d18:0/20:0), and allolithocholic acid, was already traced in the first trimester. These components are also likely involved in lipid metabolism disorders and the development of oxidative stress. 相似文献
812.
Gulim K. Mukusheva Aigerym R. Zhasymbekova Roza B. Seidakhmetova Oralgazy A. Nurkenov Ekaterina A. Akishina Sergey K. Petkevich Evgenij A. Dikusar Vladimir I. Potkin 《Molecules (Basel, Switzerland)》2022,27(11)
An efficient method of producing quinine derivatives via reaction of acylation with 4,5-dichloroisothiazole-3-, 5-arylisoxazole-3-, adamantane- and hydrochlorides of pyridine-3- and pyridine-4-carbonyl chlorides was developed. All synthesized compounds were tested for antiviral, antimicrobial and analgesic activity. The most pronounced antibacterial activity was shown by the compounds 2e, 3b, 3c and 3e with isoxazole and pyridine fragments. It was found that most of the tested compounds showed significant analgesic activity reducing the pain response of animals to the irritating effect of acetic acid. 相似文献
813.
Alina Climova Ekaterina Pivovarova Bartomiej Rogalewicz Anita Raducka Magorzata Szczesio Izabela Korona-Gowniak Agnieszka Korga-Plewko Magdalena Iwan Katarzyna Gobis Agnieszka Czylkowska 《Molecules (Basel, Switzerland)》2022,27(11)
New coordination compounds of Mn(II), Fe(III), Co(II), and Ni(II) and the biologically active ligand L (N′-benzylidenepyrazine-2-carbohydrazonamide) were synthesized and characterized by appropriate analytical techniques: elemental analysis (EA), thermogravimetric analysis (TG–DTG), infrared spectroscopy (FTIR), and flame-atomic absorption spectrometry (F-AAS). The biological activity of the obtained compounds was then comprehensively investigated. Rational use of these compounds as potential drugs was proven by ADME analysis. All obtained compounds were screened in vitro for antibacterial, antifungal, and anticancer activities. Some of the studied complexes exhibited significantly higher activity than the ligand alone. 相似文献
814.
Olga B. Abramova Grigory A. Demyashkin Valentina V. Drozhzhina Nina D. Yakovleva Ekaterina A. Kozlovtseva Tatiana P. Sivovolova Petr V. Shegay Sergey A. Ivanov Andrey D. Kaprin 《Molecules (Basel, Switzerland)》2022,27(11)
Photodynamic therapy (PDT) is an effective treatment for a number of solid malignancies. In this work, the antitumor efficacy of photodynamic therapy for murine B16 melanoma with intravenous administration of a new photosensitizer (PS) based on the chlorin e6 conjugate with a prostate-specific membrane antigen (PSMA) was studied in vivo. We have previously published the data obtained in the first part of the study: the dynamics of PS accumulation in the tumor and surrounding tissues and the antitumor efficacy of the photodynamic therapy, which was evaluated by the regression parameters and morphological characteristics of the tumors—including by the complete regression of the tumors, the absolute growth rate of the tumors among the mice with continued tumor growth, and an increase in life expectancy compared to the control. The criterion for a complete cure was the absence of signs of tumor recurrence within 90 days after therapy. The conducted studies demonstrated the high efficiency of the new photosensitizer for the photodynamic therapy of B16 melanoma. This article presents a continuation of this work, including histological studies of the zones exposed to laser irradiation on the 21st day after treatment and an assessment of the therapeutic potential of photodynamic therapy for the destruction of tumor cells. Pathological studies in the zones of photodynamic exposure revealed that the effectiveness of the PDT depended on the PS dose and the laser irradiation parameters. 相似文献
815.
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
816.
Victor P. Krasnov Vera V. Musiyak Galina L. Levit Dmitry A. Gruzdev Valeriya L. Andronova Georgii A. Galegov Iana R. Orshanskaya Ekaterina O. Sinegubova Vladimir V. Zarubaev Valery N. Charushin 《Molecules (Basel, Switzerland)》2022,27(13)
A series of pyrimidine conjugates containing a fragment of racemic 7,8-difluoro-3,4-dihydro-3-methyl-2H-[1,4]benzoxazine and its (S)-enantiomer attached via a 6-aminohexanoyl fragment were synthesized by the reaction of nucleophilic substitution of chlorine in various chloropyrimidines. The structures of the synthesized compounds were confirmed by 1H, 19F, and 13C NMR spectral data. Enantiomeric purity of optically active derivatives was confirmed by chiral HPLC. Antiviral evaluation of the synthesized compounds has shown that the replacement of purine with a pyrimidine fragment leads to a decrease in the anti-herpesvirus activity compared to the lead compound, purine conjugate. The studied compounds did not exhibit significant activity against influenza A (H1N1) virus. 相似文献
817.
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
818.
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
819.
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