—
The flux density vector of the electromagnetic energy in the Poynting form and the problem of the electron electromagnetic momentum, associated with this definition, are considered. The alternative ...flux density definition, i.e., the Umov vector whose value is identical to the Poynting vector only for empty space, is also analyzed. For qualitative comparison of differential and integral values of these two vectors in the case of non-empty space, the model of the extended electron whose charge density is inversely proportional to the quartic distance from the symmetry center is studied. It is shown that the Umov vector in this case appears more universal, since the corresponding energy conservation law does not contain a term responsible for the electromagnetic energy conversion to other energy types.
Oil-water-saturated formations of Western Siberian fields represented by polymictic sandstones are often characterized by strong granulometric heterogeneity. This is the reason for an incorrect ...assessment of the physicochemical properties of reservoirs, including wettability. On the example of the BS9 - BS11 formations of two fields of Surgut oil and gas region, the distribution of wettability of core samples was analyzed. An analysis of the modeling results for the hydrocarbon phase displacement by oil-saturated reservoir water was carried out using the Tulbovich method. To assess reliability of the wettability values, it was proposed to correlate the difference in the masses of water and kerosene displaced during capillary impregnation and centrifugation with differences in the mass of water and kerosene in water-and kerosene-saturated samples. The method was used to plot the distribution of porosity, permeability and relative clay content on the wettability parameter by capillary impregnation and centrifugal displacement. The results obtained were compared with similar dependences of the reservoir properties and clay content on the general wettability parameter. The type of wettability of core samples with good reservoir properties is validated in complex, low-permeability reservoirs with a high content of clay material. It is recommended to use the results of modeling the displacement by capillary impregnation and centrifugation with differences in the mass of water and kerosene.
The results of improved automated analytical control for optimizing reliability and content-richness in monitoring the condensate-feed system of a nuclear power plant on the basis of real-time ...assessment of the static, dynamic, and frequency characteristics of in-loop physicochemical processes forming the ionic composition of process water are summarized. It is shown under the operating conditions of a real object that the information redundancy of the means of automatic analytical control significantly increases the reliability of conclusions drawn about an increase in the amplitude and frequency of ingress of ionic impurities into the working medium of the main condenser at an early stage of leak development in its cooling pipelines.
High oil reserves characterize most fields in Western Siberia. However, along with this, zones of the productive formation that are poorly involved in development and production wells, in which ...products with a high proportion of water are produced, are distinguished within limits. For understanding the causes of this problem, it is important to consider the material composition of the reservoirs. In particular, it is necessary to consider the clay content, which is associated with the reservoir properties of rocks, hydrophilicity, hydrophobicity and, accordingly, with wettability. The article examined and analyzed a representative sample of core study of two wells in the Gubkinsky oil and gas region, which suggested the possible reasons for the lack of oil reserves.
Antitumor activity of the novel pyridine derivative Ekaterina, V. Blinova; Epishkina, Anna V.; Tumutolova, Oksana M. ...
Research results in pharmacology (English ed.),
09/2022, Letnik:
8, Številka:
3
Journal Article
Recenzirano
Odprti dostop
Introduction: The study aim was to explore a toxicological property and antitumor action of the novel pyridine derivative LHT-17-19 in cell culture and on experimental models of lung cancer in mice.
...Materials and methods: The study was performed on male and female ICR(CD-1), male BALB/c, male BALB/c nu/nu mice. Pyridine derivative (LHT-17-19) was studied as water-soluble pharmaceutical substance. Acute toxicity was evaluated in groups of 5 animals, and the results were analyzed by Finney. Antitumor and antimetastatic activity was studied in syngeneic and xenograft models of lung cancer in mice.
Results and discussion: LHT-17-19 belongs to class 3 of the toxicity classification of chemicals in accordance with GOST 12.1.007–76. The substance demonstrated an antitumor and antimetastatic property in mice with syngeneic tumor Lewis lung carcinoma as well as on the heterotopic tumor model of non-small cell lung cancer in humanized animals.
Conclusion: LHT-17-19 belongs to class 3 of the toxicity classification of chemicals in accordance with WHO recommendation. LHT-17-19 exerts antitumor and antimetastatic property on both syngeneic and patient-derived lung cancer xenograft murine models.
Graphical abstract:
Introduction: The study aim was to explore a neuroprotective action of magnesium (LKhT-317) and zinc (LKhT-318) taurine salts on experimental models of reperfusion brain damage in rats and cell ...culture.
Materials and methods: The study was performed on male Sprague Dawley rats, and rat’s hippocampal mixed neuroglial cell culture. Magnesium- (LKhT-317) and zinc-containing (LKhT-318) derivatives of taurine were studied. Reperfusion brain damage was induced 30 min after intraluminal cerebral middle artery occlusion. Severity of the injury was assessed by local blood flowmetry, neurological symptoms scaling and brain tissue staining. Levels of IL-1b, IL-10 and TNF-alpha in tissue were determined by qualitative ELISA. Caspase-3 and Bcl-2 expressions were detected by IHC. Neurons survival was assessed by cytochemistry. Cellular calcium responses were detected by fluorescent microscopy of Fura-2-containig cells.
Results and discussion: Metal-containing taurine derivatives – LKhT-317 and LKhT-318 – demonstrated a sufficient neuroprotective property in rats with a reperfusion-induced brain injury. Both derivatives effectively prevented severity of the animals’ brain damage, motor deficiency, reduction of microvascular perfusion, and proinflammatory cytokines production. Magnesium-containing compound LKhT-317 was comparatively more effective than zinc-containing one. LKhT-317 possessed an anti-apoptotic action in vivo, and protected neurons from OGD-mediated cell death in mixed hippocampal culture. The aforementioned actions may be associated with an LKhT-317 inhibitory effect on NMDA-induced cellular Ca2+ response and, therefore, the anti-excitotoxic property of the compound.
Conclusion: Magnesium- and zinc-containing taurine derivatives may be considered as promising neuroprotectors in the reperfusion-induced brain injury.
2-Amino-4H-chromene derivatives possess anticancer property proved on different in vivo and in vitro models of malignancies such breast, nasopharyngeal, bladder, ovary carcinomas, astrocytoma, and ...osteosarcoma. We assumed it might be effective to apply one of the derivatives as promising approach to lung carcinoma treatment. to evaluate how novel 4-aryl substituted 2-amino-4H-chromene derivative AX-554 impacts tumor growth and progression, as well as possible mechanisms for anticancer effect development on in vivo patient-derived heterotopic xenograft model of lung carcinoma in mice. This was an experimental in vivo study. 40 nu/nu BALB/c female mice were randomly allocated into four equal groups: Intact, control, reference, and main group. Animals of three latter groups were ingrafted with human-derived lung adenocarcinoma. Antitumor and antimetastatic action of AX-554 novel aminochromone derivative as a substance were studied. Mice survival was registered. Kinase of anaplastic lymphoma (ALK), tubulin Beta-3 (TUBB3), and c-mesenchymal-epithelial transition (MET) concentrations in the prime tumor nodes homogenates were determined by quantitative enzyme-linked immunosorbent assay. Dannet's parametric criterion and the nonparametric exact Fisher test were used. The normality of the distribution was determined using ANOVA. The survival curve was analyzed using Gehan's criterion with the Yates's correction. Aminochromone derivative possesses an inhibitory effect on human lung adenocarcinoma transplanted into nu/nu BALB/c female mice, as well as significant antimetastatic activity. About 50 mg/kg/day AX-554 intragastric course increases animals' life expectancy of more than 3.3 times when compared with the control and induces remission in 60% of cases. The anticancer effect of the derivative is due to anti-ALK-mediated activation of tumor cells apoptosis and suppression TUBB3-dependent cell proliferation.
Laplace, analyzing the stability of the Solar System, was the first to calculate that the velocity of the motion of force fields can significantly exceed the velocity of light waves. In ...electrodynamics, the Coulomb field should rigidly accompany its source for instantaneous force action in distant regions. Such rigid motion was recently inferred from experiments at the Frascati Beam Test Facility with short beams of relativistic electrons. The comments of the authors on their observations are at odds with the comments of theoreticians on retarded potentials, which motivates a detailed study of the positions of both sides. Predictions of measurements, based on the Lienard–Wiechert potentials, are used to propose an unambiguous scheme for testing the rigidity of the Coulomb field. Realization of the proposed experimental scheme could independently refute or support the assertions of the Italian physicists regarding the rigid motion of Coulomb fields and likewise the nondual field approach to macroscopic reality.
Introduction: EGFR-activating overexpression or somatic mutations are common in different human cancers. In this regard, the search for promising ways to control the carcinogenic transformation of ...tumor cells and the progression of malignant tumors expressing EGFR seems to be one of the most promising and developing areas of modern molecular pathology and pharmacology. Material and Methods: An antitumor activity of a novel compound, a pyridine carboxylic acid derivative LHT-17-19, was studied. The molecule was developed and synthesized at the Department of Chemistry, Drug Design and Technology of All-Russian Research Center for Biological Active Compounds Safety (Russia). The study was carried out in cell cultures of stomach cancer (Hs746T, AGS and MKN1) and patient-derived organoid (PDO) model of breast cancer (BC) expressing wild-type EGFR. Results: It was shown that LHT-17-19 induced concentration-dependent cytotoxicity of EGFR-expressing gastric cancer cells of all the aforementioned cultures. Pathomorphological, immunohistochemical and molecular validation of BC organoids derived from ductal breast carcinoma cells of a 68-year-old patient was done. PDOs were established as ER-negative, PR-negative, Her2/neu-negative, EGFR-positive with 35% of the Ki-67 expression index. In addition, the tumor cells translocation was resulted in a loss of ER expression and PDOs molecular pattern conversion towards a more aggressive triple negative type. PDOs incubation with 0.5-60.0 µM LHT-17-19 was accompanied not only by inhibition of their growth and proliferation, but also by significant cytoreduction. Conclusion: Thus, in two-dimensional and three-dimensional tumor cell cultures, the possibility of controlling the oncogenic expression of EGFR with the acridone compound 9-ammonium-3,3-dimethyl-3,4-dihydroacridine-1(2H)-OH L-2-hydroxybutanedivacate (LHT-17-19) was shown.
PDF
