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81.
Polyakov Andrey P. Mordovskiy Alexander V. Ratushnyy Mikhail V. Rebrikova Irina V. 《Oral and maxillofacial surgery》2021,25(2):271-277
Oral and Maxillofacial Surgery - Presently, the functional reconstruction of the tongue in patients after subtotal or total glossectomy with the removal of the oral floor muscles and spearing of... 相似文献
82.
Irina S. Vasil'eva Galina P. Shumakovich Maria E. Khlupova Roman B. Vasiliev Viktor V. Emets Vera A. Bogdanovskaya Olga V. Morozova Alexander I. Yaropolov 《RSC advances》2020,10(55):33010
The development of novel materials with improved functional characteristics for supercapacitor electrodes is of current concern and calls for elaboration of innovative approaches. We report on an eco-friendly enzymatic synthesis of a composite based on poly(3,4-ethylenedioxythiophene) (PEDOT) and multi-walled carbon nanotubes (MWCNTs). The redox active compound, sodium 1,2-naphthoquinone-4-sulfonate (NQS), was used as a dopant for the backbone of the polymer. Oxidative polymerization of 3,4-ethylenedioxythiophene (EDOT) was catalyzed by a high redox potential laccase from the fungus Trametes hirsuta. Atmospheric oxygen served as an oxidant. A uniform thin layer of NQS-doped PEDOT formed on the surface of MWCNTs as a result of the enzymatic polymerization. The PEDOT–NQS/MWCNT composite showed a high specific capacitance of ca. 575 F g−1 at a potential scan rate of 5 mV s−1 and an excellent cycling stability within a potential window between −0.5 and 1.0 V, which makes it a promising electrode material for high-performance supercapacitors.The use of redox active NSQ as a dopant of PEDOT dramatically increases the specific capacitance and cyclic stability of enzymatically synthesized PEDOT–NSQ/MWCNT composite. 相似文献
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Deletion of the M5 muscarinic acetylcholine receptor attenuates morphine reinforcement and withdrawal but not morphine analgesia 总被引:15,自引:0,他引:15 下载免费PDF全文
Basile AS Fedorova I Zapata A Liu X Shippenberg T Duttaroy A Yamada M Wess J 《Proceedings of the National Academy of Sciences of the United States of America》2002,99(17):11452-11457
Little is known about the physiological roles of the M5 muscarinic receptor, the last member of the muscarinic receptor family (M1-M5) to be cloned. In the brain, the M5 receptor subtype is preferentially expressed by dopaminergic neurons of the substantia nigra and the ventral tegmental area. Dopaminergic neurons located in the ventral tegmental area are known to play important roles in mediating both the rewarding effects of opiates and other drugs of abuse and the manifestations of opiate/drug withdrawal symptoms. We therefore speculated that acetylcholine-dependent activation of M5 receptors might modulate the manifestations of opiate reward and withdrawal. This hypothesis was tested in a series of behavioral, biochemical, and neurochemical studies using M5 receptor-deficient mice (M5-/- mice) as novel experimental tools. We found that the rewarding effects of morphine, as measured in the conditioned place preference paradigm, were substantially reduced in M5-/- mice. Furthermore, both the somatic and affective components of naloxone-induced morphine withdrawal symptoms were significantly attenuated in M5-/- mice. In contrast, the analgesic efficacy of morphine and the development of tolerance to the analgesic effects of morphine remained unaltered by the lack of M5 receptors. The finding that M5 receptor activity modulates both morphine reward and withdrawal processes suggests that M5 receptors may represent a novel target for the treatment of opiate addiction. 相似文献
86.
Kujiraoka T Hattori H Ito M Nanjee MN Ishihara M Nagano M Iwasaki T Cooke CJ Olszewski WL Stepanova IP Egashira T Miller NE 《Atherosclerosis》2004,176(1):57-62
We have previously shown that intravenous apolipoprotein (apo) A-I/phosphatidylcholine (apo A-I/PC) discs increase plasma high-density lipoprotein (HDL) concentration in humans. We have now studied the associated changes in two enzymes, paraoxonase (PON) and platelet-activating factor acetylhydrolase (PAF-AH) that are carried in whole or in part by HDLs, and are thought to influence atherogenesis by hydrolyzing oxidized phospholipids in lipoproteins. Apo A-I/PC discs (40 mg/kg over 4 h) were infused into eight healthy males. Although plasma apo A-I and HDL cholesterol increased on average by 178 and 158%, respectively, plasma total PON and total PAF-AH concentrations did not rise. By the end of the infusion, HDL-associated PAF-AH had increased by 0.56 +/- 0.14 microg/mL (mean +/- S.D., P < 0.01), and nonHDL-associated PAF-AH had decreased by 0.84 +/- 0.11 microg/mL (P < 0.05). These changes were accompanied by an increase in the HDL-associated PAF-AH/apo A-I ratio from 0.19 to 0.35 (P < 0.05), and by a decrease in the nonHDL-associated PAF-AH/apo B ratio from 2.1 to 1.4 (P < 0.05). No changes in PON or PAF-AH concentrations were detected in prenodal lymph (tissue fluid), collected continuously from the leg. Our results show that the total concentrations of PON and PAF-AH in plasma are uninfluenced by plasma HDL concentration. PAF-AH transfers readily between HDLs and LDLs in vivo, and its distribution between them is determined partly by their relative concentrations and partly by HDL composition. 相似文献
87.
Molecular characteristic of acute leukemias with t(16;21)/<Emphasis Type="Italic">FUS-ERG</Emphasis>
88.
Jason C. Burton Shang Wang C. Allison Stewart Richard R. Behringer Irina V. Larina 《Biomedical optics express》2015,6(7):2713-2723
The understanding of the reproductive events and the molecular mechanisms regulating fertility and infertility in humans relies heavily on the analysis of the corresponding phenotypes in mouse models. While molecular genetic approaches provide significant insight into the molecular regulation of these processes, the lack of live imaging methods that allow for detailed visualization of the mouse reproductive organs limits our investigations of dynamic events taking place during the ovulation, the fertilization and the pre-implantation stages of embryonic development. Here we introduce an in vivo three-dimensional imaging approach for visualizing the mouse oviduct and reproductive events with micro-scale spatial resolution using optical coherence tomography (OCT). This method relies on the natural tissue optical contrast and does not require the application of any contrast agents. For the first time, we present live high-resolution images of the internal structural features of the oviduct, as well as other reproductive organs and the oocytes surrounded by cumulus cells. These results provide the basis for a wide range of live dynamic studies focused on understanding fertility and infertility.OCIS codes: (110.4500) Optical coherence tomography, (170.3880) Medical and biological imaging, (170.5380) Physiology 相似文献
89.
Takamitsu Hattori Darson Lai Irina S. Dementieva Sherwin P. Monta?o Kohei Kurosawa Yupeng Zheng Louesa R. Akin Kalina M. ?wist-Rosowska Adrian T. Grzybowski Akiko Koide Krzysztof Krajewski Brian D. Strahl Neil L. Kelleher Alexander J. Ruthenburg Shohei Koide 《Proceedings of the National Academy of Sciences of the United States of America》2016,113(8):2092-2097
90.
Periodontitis in Rats Induces Systemic Oxidative Stress That Is Controlled by Bone‐Targeted Antiresorptives 下载免费PDF全文
Sehkar Oktay Sasanka S. Chukkapalli Mercedes F. Rivera‐Kweh Irina M. Velsko L. Shannon Holliday Lakshmyya Kesavalu 《Journal of periodontology》2015,86(1):137-145
Background: Periodontitis is a chronic, polymicrobial inflammatory disease that degrades connective tissue and alveolar bone and results in tooth loss. Oxidative stress has been linked to the onset of periodontal tissue breakdown and systemic inflammation, and the success of antiresorptive treatments will rely on how effectively they can ameliorate periodontal disease–induced oxidative stress during oral infection. Methods: Rats were infected with polybacterial inoculum consisting of Porphyromonas gingivalis, Treponema denticola, and Tannerella forsythia, as an oral lavage every other week for 12 weeks. Daily subcutaneous injections of enoxacin, bis‐enoxacin, alendronate, or doxycycline were administered for 6 weeks after 6 weeks of polybacterial infection in rats. The serum levels of oxidative stress parameters and antioxidant enzymes, including glutathione peroxidase, superoxide dismutase, and catalase, were evaluated in each of the infected, treated, and sham‐infected rats. Results: Rats infected with the periodontal pathogens displayed a five‐fold increase in the oxidative stress index compared with controls as a result of increased levels of serum oxidants and decreases in total antioxidant activity. The overall decrease in antioxidant activity occurred despite increases in three important antioxidant enzymes, suggesting an imbalance between antioxidant macromolecules/small molecules production and antioxidant enzyme levels. Surprisingly, the bone‐targeted antiresorptives bis‐enoxacin and alendronate inhibited increases in oxidative stress caused by periodontitis. Bis‐enoxacin, which has both antiresorptive and antibiotic activities, was more effective than alendronate, which acts only as an antiresorptive. Conclusion: To the best of the authors’ knowledge, this is the first study to demonstrate that the increased oxidative stress induced by periodontal infection in rats can be ameliorated by bone‐targeted antiresorptives. 相似文献