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121.
122.
Olga A. Goncharova Andrey Yu. Luchkin Nina P. Andreeva Vadim E. Kasatkin Sergey. S. Vesely Nikolay N. Andreev Yurii I. Kuznetsov 《Materials》2022,15(4)
It has been shown by a set of corrosion, electrochemical and physical methods that a chamber corrosion inhibitor that consists of a mixture of octadecylamine (ODA) and benzotriazole (BTA) efficiently protects copper and brass from atmospheric corrosion and can be used for the temporary protection of metal items. The optimum temperatures of treatment with the ODA + BTA mixed inhibitor is 120 °C for brass and 100 °C for copper. One-hour treatment in ODA + BTA vapors at these temperatures results in the formation of nanosized adsorption films on the surface of these metals. These films stabilize the passive state and provide efficient temporary protection of metal items. The ODA + BTA inhibitor is superior to its components in terms of protective aftereffect. Our analysis of the mutual effect of BTA and ODA indicated that they show an antagonism of protective action on copper, but there is also a synergistic enhancement in the case of brass. Electrochemical impedance spectroscopy studies demonstrate that the inhibitors in question mainly act by using a blocking mechanism on copper and brass. Chamber treatment of the metals studied in vapors of the ODA + BTA mixture resulted in a noticeable hydrophobization of the copper surface and an insignificant effect on the brass surface. Chamber treatment of copper samples with artificially created polymodal roughness made it possible to obtain a superhydrophobic surface. 相似文献
123.
Anton S. Voronin Yurii V. Fadeev Mstislav O. Makeev Pavel A. Mikhalev Alexey S. Osipkov Alexander S. Provatorov Dmitriy S. Ryzhenko Gleb Y. Yurkov Mikhail M. Simunin Darina V. Karpova Anna V. Lukyanenko Dieter Kokh Dashi D. Bainov Igor A. Tambasov Sergey V. Nedelin Nikita A. Zolotovsky Stanislav V. Khartov 《Materials》2022,15(4)
Embedded copper mesh coatings with low sheet resistance and high transparency were formed using a low-cost Cu seed mesh obtained with a magnetron sputtering on a cracked template, and subsequent operations electroplating and embedding in a photocurable resin layer. The influence of the mesh size on the optoelectric characteristics and the electromagnetic shielding efficiency in a wide frequency range is considered. In optimizing the coating properties, a shielding efficiency of 49.38 dB at a frequency of 1 GHz, with integral optical transparency in the visible range of 84.3%, was obtained. Embedded Cu meshes have been shown to be highly bending stable and have excellent adhesion strength. The combination of properties and economic costs for the formation of coatings indicates their high prospects for practical use in shielding transparent objects, such as windows and computer monitors. 相似文献
124.
Tubulin binding blocks mitochondrial voltage-dependent anion channel and regulates respiration 总被引:3,自引:0,他引:3 下载免费PDF全文
Tatiana K. Rostovtseva Kely L. Sheldon Elnaz Hassanzadeh Claire Monge Valdur Saks Sergey M. Bezrukov Dan L. Sackett 《Proceedings of the National Academy of Sciences of the United States of America》2008,105(48):18746-18751
Regulation of mitochondrial outer membrane (MOM) permeability has dual importance: in normal metabolite and energy exchange between mitochondria and cytoplasm and thus in control of respiration, and in apoptosis by release of apoptogenic factors into the cytosol. However, the mechanism of this regulation, dependent on the voltage-dependent anion channel (VDAC), the major channel of MOM, remains controversial. A long-standing puzzle is that in permeabilized cells, adenine nucleotide translocase (ANT) is less accessible to cytosolic ADP than in isolated mitochondria. We solve this puzzle by finding a missing player in the regulation of MOM permeability: the cytoskeletal protein tubulin. We show that nanomolar concentrations of dimeric tubulin induce voltage-sensitive reversible closure of VDAC reconstituted into planar phospholipid membranes. Tubulin strikingly increases VDAC voltage sensitivity and at physiological salt conditions could induce VDAC closure at <10 mV transmembrane potentials. Experiments with isolated mitochondria confirm these findings. Tubulin added to isolated mitochondria decreases ADP availability to ANT, partially restoring the low MOM permeability (high apparent Km for ADP) found in permeabilized cells. Our findings suggest a previously unknown mechanism of regulation of mitochondrial energetics, governed by VDAC and tubulin at the mitochondria–cytosol interface. This tubulin–VDAC interaction requires tubulin anionic C-terminal tail (CTT) peptides. The significance of this interaction may be reflected in the evolutionary conservation of length and anionic charge in CTT throughout eukaryotes, despite wide changes in the exact sequence. Additionally, tubulins that have lost significant length or anionic character are only found in cells that do not have mitochondria. 相似文献
125.
Aronson D Hammerman H Beyar R Yalonetsky S Kapeliovich M Markiewicz W Goldberg A 《International journal of cardiology》2008,130(3):380-385
Older age is an independent predictor of mortality after percutaneous coronary intervention (PCI) in patients with Non-ST elevation Acute Coronary Syndrome (ACS). GPIIb/IIIa inhibitors are proved to improve outcome in high risk patients, but conflicting data are available about the effects of these inhibitors in elderly. Accordingly, we studied a consecutive population of elderly patients undergoing PCI for Non-ST elevation ACS. A total of 500 patients were divided in: GPI group (247 pts; mean age 77 ± 1.9 years) treated by stenting plus abciximab and, no GPI group (253 pts; mean age 77 ± 2.4 years) treated by stenting alone. Propensity analysis was used to account for the nonrandomized use of GPIIb/IIIa inhibitors. During hospitalization, incidence of death was similar among groups (3.2% vs 4.6%) without difference regarding incidence of major (1.6% vs 1.1%) and minor bleedings (4% vs 3%). At long-term follow-up the rate of death was significantly lower in GPI group (4.5% vs 12.3%; p = 0.002) as well as the rate of acute myocardial infarction (2.8% vs 11.1%; p = 0.0001), and pre-PCI (5.7% vs 13.4%; p = 0.003). Cox regression analysis identified abciximab use as an independent predictor of lower long-term major adverse cardiac event (MACE) after adjustment for propensity score (Exp (B) 0.620, 95%CI 0.394–0.976, p = 0.039). Our results suggest that addition of abciximab to stenting improves outcome in elderly patients with Non-ST elevation ACS, leading to an absolute benefit for reduction of death and MACE, with an acceptable rate of major and minor bleedings. 相似文献
126.
Vladimir Shvartz Maria Sokolskaya Andrey Petrosyan Artak Ispiryan Sergey Donakanyan Leo Bockeria Olga Bockeria 《Pathophysiology》2022,29(1):106
Background: Understanding of the risk factors for the development of adverse outcomes after aortic valve replacement is necessary to develop timely preventive measures and to improve the results of surgical treatment. Methods: We analyzed patients with aortic stenosis (n = 742) who underwent surgical treatment in the period 2014–2020. The average age was 63 (57;69) years—men 58%, women 42%. Results: The hospital mortality rate was 3% (22 patients). The following statistically significant threshold values (cut-off points) were obtained in the ROC analysis: aortic cross-clamp time > 93 min AUC (CI) 0.676 (0.640–0.710), p = 0.010; cardiopulmonary bypass time > 144 min AUC (CI) 0.809 (0.778–0.837), p < 0.0001, hemoglobin before op <120 g/L. AUC (CI) 0.762 (0.728–0.793), p < 0.0001, hematocrit before op <39% AUC (CI) 0.755 (0.721–0.786), p < 0.001, end-diastolic dimension index >2.39 AUC (CI) 0.647 (0.607–0.686), p = 0.014, end-systolic dimension index > 1.68 AUC (CI) 0.657 (0.617–0.695), p = 0.009. Statistically significant independent predictors of hospital mortality were identified: BMI > 30 kg/m2 (OR 2.84; CI 1.15–7.01), ischemic heart disease (OR 3.65; CI 1.01–13.2), diabetes (OR 3.88; CI 1.38–10.9), frequent ventricular ectopy before operation (OR 9.78; CI 1.91–50.2), mitral valve repair (OR 4.47; CI 1.76–11.3), tricuspid valve repair (OR 3.06; CI 1.09–8.58), 3 and more procedures (OR 4.44; CI 1.67–11.8). Conclusions: The hospital mortality rate was 3%. The main indicators associated with the risk of death were: diabetes, overweight (body mass index more than 30 kg/m2), frequent ventricular ectopy before surgery, hemoglobin level below 120 g/L, hematocrit level below 39%, longer cardiopulmonary bypass time and aortic cross-clamp time, additional mitral and tricuspid valve interventions. 相似文献
127.
128.
Elena V. Ukhatskaya Sergey V. Kurkov Susan E. Matthews Thorsteinn Loftsson 《Journal of pharmaceutical sciences》2013,102(10):3485-3512
Calix[n]arenes (CAs) are supramolecular compounds able to form guest-host inclusion complexes with metal ions, small organic molecules, and small moieties of larger molecules. Although the CA literature is extensive, relatively few publications deal with water-soluble CAs, especially those containing nitrogen-based functionality. These CAs possess antibacterial and antifungal activity. Because of their molecular structure, they are surface active and also able to form water-soluble drug complexes, giving additional potential as enabling pharmaceutical excipients. This article provides an overview of the published data regarding synthesis, physicochemical properties, and pharmaceutical application of water-soluble CAs with emphasis on those that contain nitrogen-based substituents in their structure, particularly aminoCAs. In particular, it describes state-of-the-art in complexation of water-soluble CAs with pharmaceutically relevant ions and organic molecules up to amino acids, DNA, and proteins. 相似文献
129.
Irving F. Hoffman Carl A. Latkin Polina V. Kukhareva Sergey V. Malov Julia V. Batluk Alla V. Shaboltas Roman V. Skochilov Nicolay V. Sokolov Sergei V. Verevochkin Michael G. Hudgens Andrei P. Kozlov 《AIDS and behavior》2013,17(7):2510-2520
We evaluated the efficacy of a peer-educator network intervention as a strategy to reduce HIV acquisition among injection drug users (IDUs) and their drug and/or sexual networks. A randomized controlled trial was conducted in St. Petersburg, Russia among IDU index participants and their risk network participants. Network units were randomized to the control or experimental intervention. Only the experimental index participants received training sessions to communicate risk reduction techniques to their network members. Analysis includes 76 index and 84 network participants who were HIV uninfected. The main outcome measure was HIV sero-conversion. The incidence rates in the control and experimental groups were 19.57 (95 % CI 10.74–35.65) and 7.76 (95 % CI 3.51–17.19) cases per 100 p/y, respectively. The IRR was 0.41 (95 % CI 0.15–1.08) without a statistically significant difference between the two groups (log rank test statistic X2 = 2.73, permutation p value = 0.16). Retention rate was 67 % with a third of the loss due to incarceration or death. The results show a promising trend that this strategy would be successful in reducing the acquisition of HIV among IDUs. 相似文献
130.
Karen Hennessey W. William SchluterXiaojun Wang Liliane BoualamYoungmee Jee Jorge Mendoza-AldanaSigrun Roesel Sergey DiorditsaJohn Ehrenberg 《Vaccine》2014
Accelerated disease control goals have long been appreciated for their role in galvanizing commitment and bringing a sense of urgency for disease prevention. WHO's Western Pacific Region has 14 on-going communicable disease reduction goals including 1 targeting eradication, 10 targeting elimination, and 3 control initiatives. These goals cover mother-to-child transmission of HIV, congenital syphilis, tuberculosis, leprosy, five parasitic diseases and four vaccine-preventable diseases (VPD). The initiatives have distinct objectives, approaches, and means in which to measure achievement of the goals. 相似文献