Non-specific binding of antibodies in immunohistochemistry: Fakes and facts

Protocols for blocking non-specific antibody (Ab) binding in immunohistochemistry are based on rather contradictory and outdated reports. This prompted us to prove, whether non-specific Ab binding may really lead to unwanted background staining in routinely processed cell and tissue probes. In this study, the probes were fixed and processed according to routine protocols with and without a blocking step (goat serum or BSA). Surprisingly, all Ab in probes processed without a blocking step did not show any propensity towards non-specific binding that might lead to background staining, thus implying that endogenous Fc receptors do not retain their ability to bind Fc portion of Ab after standard fixation. Likewise in routinely fixed probes, we did not find any non-specific Ab binding ascribed to a combination of ionic and hydrophobic interactions. The traditionally used protein blocking step is useless in immunostaining of routinely fixed tissues

The non-obligatory role of endothelial cells in the relaxation of arterial smooth muscle by acetylcholine

The concept of Endothelium Derived Relaxing Factor (EDRF), put forward by Furchgott in the earlier 80s of the past century, implies that nitric oxide (NO) produced by NO synthase (NOS) in the endothelium in response to acetylcholine (ACh) passively diffuses to the underlying vascular smooth muscle cells (VSMC) thereby reducing vascular tension. It was thought that VSMC do not express NOS by themselves, but to the time of those studies immunohistochemical techniques were not what they are now. State-of-the-art immunohistochemistry permits nowadays to localize NOS both to the endothelium and to VSMC. However, the principal question remained unanswered, is the NO generation by VSMC physiologically relevant? We hypothesized that the destruction of the vascular wall anatomical integrity by rubbing the blood vessel intimal surface may increase vascular superoxides that, in turn, reduce NO bioactivity. To address this issue, we examined ACh-induced vasorelaxation in endothelium-deprived blood vessels under protection against oxidative stress and found that superoxide scavengers - tempol and N-acetyl-L-cysteine - restored vasodilatory responses to ACh in endothelium-deprived blood vessels without influencing the vascular wall tension in intact blood vessels. Herewith we provided the first evidence that VSMC can release NO in amounts sufficient to account for the vasorelaxatory response to ACh. In contrast to the commonly accepted concept of the obligatory role of endothelial cells in the relaxation of arterial smooth muscle, the local NO generation by VSMC can modulate vascular functions in an endothelium-independent manner

Electronic Presentation at the Lessons of «World Art Culture»

При финансовой поддержке Российского гуманитарного научного фонда, проект № 08-06-14135

Musical computer technologies: historical aspect

При финансовой поддержке Российского гуманитарного научного фонда, проект № 07-06-14162

Microwave response of bulk MgB2 samples of different granularity

The microwave response of three high-density bulk MgB2 samples has been investigated in the linear and nonlinear regimes. The three samples, characterized by different mean size of grains, have been obtained by reactive infiltration of liquid Mg in powdered B preforms. The linear response has been studied by measuring the microwave surface impedance; the nonlinear response by detecting the power radiated by the sample at the second-harmonic frequency of the driving field. Our results suggest that bulk MgB2 prepared by the liquid Mg infiltration technique is particularly promising for manufacturing resonant cavities operating at microwave frequencies.Comment: 4 pages, 2 embedded figures; Proceedings of 7th EUCAS Conference (11-15 September 2005, Vienna - Austria

Reviewing one year milestone survey results

The funding of the project allowed for accepting three test-cohorts (in total 48students) who were allowed to take IPSDS courses at no costs in exchange for participation in the evaluation. The goal of this report is to summarize key results of the one year follow-up survey conducted three times since 2017 (for the first cohort (n=16) in 2017 and 2018 and for the second cohort (n=15) in 2018)

Two-dimensional pulsed electron spin resonance characterization of 15N-labeled archaeal Rieske-type ferredoxin

AbstractTwo-dimensional electron spin-echo envelope modulation (ESEEM) analysis of the uniformly 15N-labeled archaeal Rieske-type [2Fe–2S] ferredoxin (ARF) from Sulfolobus solfataricus P1 has been conducted in comparison with the previously characterized high-potential protein homologs. Major differences among these proteins were found in the hyperfine sublevel correlation (HYSCORE) lineshapes and intensities of the signals in the (++) quadrant, which are contributed from weakly coupled (non-coordinated) peptide nitrogens near the reduced clusters. They are less pronounced in the HYSCORE spectra of ARF than those of the high-potential protein homologs, and may account for the tuning of Rieske-type clusters in various redox systems

The Organization Involved in the Production of Industrial Enterprises of the Participating Countries of the EAEC Secondary Material Resources on the Principles of Logistics

The use of secondary material resources is a significant factor of economy of material resources in the national economy. A major role in the expansion of the scope of waste production is the correct definition of current and capital expenditures on the waste. It is important to understand that the generation of waste. This is an inevitable process, so it is necessary introduction of new resource-saving technologies and use of raw materials