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Degradation of oil hydrocarbons artificially introduced into bottom sediments in a bioelectrochemical system of a membrane-free (silt) type was studied. Passive bioelectrochemical stimulation by means of electrodes connected by an external circuit with a resistance of 1 kΩ, with an average electric current of ~85 µA was found to cause an increase in degradation during two months from 23.0 to 57.9%. Contamination of bottom sediments with oil (1.32 g/kg) slightly decreased the current in the external circuit of the bioelectrochemical system. The relationship was revealed between the degree of oil degradation and predominant utilization of the lighter n-alkanes in the C14H30–C30H62 series, compared with both the original oil and the residual hydrocarbons of the control. An increase in the representation of the alkB alkane monooxygenase genes relative to the 16S rRNA gene in the total DNA isolated from the sediments was induced by the introduction of hexadecane, both in the case of electrochemical stimulation and in the control. The results may be of interest for the development of new methods of bioelectrochemical removal of organic pollutants from anaerobic environments. [ABSTRACT FROM AUTHOR]

A significant variation in the relative representation of copies of bacterial genes of dye-decolorizing DyP peroxidases typical for the genus Shewanella and a number of other microorganisms was found in the bottom sediments of freshwater reservoirs. It was found that the specific rate of decolorization of crystal violet in a laboratory bioelectrochemical system by a mixed culture of bottom sediments, which showed the highest representation of DyP genes, depended on the method of electrical stimulation of the external circuit and the concentration of the dye. After an increase in the concentration of more than 20 microns, the maximum speed was achieved in the presence of an ionistor polarly connected to the external electrical circuit of the bioelectrochemical system and amounted to 3.23 ± 0.11 μM/h, while with the opposite polarity connection, a minimum value of 2.07 ± 0.08 μM/h was observed. In the case of an open circuit and a resistor, similar indicators occurred with 2.88 ± 0.09 and 2.67 ± 0.12 μM/h, respectively. When analyzing the decolorization products, a consistent decrease in the maxima of the absorption bands of the dye was noted, indicating its more complete degradation by the mixed culture. The results may be of interest for the development of methods to improve the efficiency of bioelectrochemical methods of environmental biotechnology by electrostimulation of the external circuit. [ABSTRACT FROM AUTHOR]

The bioelectrogenic activity of sediments of the natural microbial assemblage of Peter the Great Bay, Sea of Japan, was studied in a year-round experiment with parallel temperature, illumination, and water electrical conductivity monitoring using benthic microbial fuel cells (MFC) and automatic online monitoring. Several variants of underwater devices, including benthic microbial fuel cells, monitoring water environment sensor, information collection and transmission systems, have been developed. This device has an electrical voltage of up to 216 mV and a specific power of up to 239 mW/m2. The electrogenic activity of natural microflora depends on water temperature and reaches a maximum in summer with a temperature of about 20–25°C. The introduction of toxicants such as hydrocarbons and cadmium into sludge led to suppression of microbial electrogenesis. However, the introduction of inductor substances of microbial sulfidogenesis stimulated microbial electrogenesis. The possibility of functioning of the benthic MFC in the field of Peter the Great Bay in different climate periods is shown. It is demonstrated that such experimental devices can be a basis for autonomous stations monitoring the state of the marine environment over a long time period and in a wide range of changing conditions. Automatic recording of water temperature, illumination, and salinity with a frequency of 48 times a day was done over 13 months (November 28, 2019–December 31, 2020). The electrogenic activity of this microbiota upon MFC scaling can potentially become a new renewable energy source for low-power marine electronics, including those used in mariculture. [ABSTRACT FROM AUTHOR]

A new method was proposed for the preparation of 5-amino-3-(cyanomethyl)-1H-pyrazole-4-carbonitrile by reaction of the potassium salt of malononitrile dimer with hydrazinium sulfate. The reaction of 5-amino-3(cyanomethyl)-1H-pyrazole-4-carbonitrile with aromatic aldehydes in the presence of catalytic amounts of morpholine leads to the formation of Knoevenagel condensation products. Aminomethylation of the resulting (Z)-5-amino-3-(2-aryl-1-cyanovinyl)-1H-pyrazole-4-carbonitriles with primary aromatic amines and excess aqueous HCHO in refluxing DMF leads to the formation of 7-(2-aryl-1-cyanovinyl)-1,2,3,4-tetrahydropyrazolo[1,5-a][1,3,5]triazine-8-carbonitriles. Bioavailability parameters were studied in silico, and possible protein targets were predicted by protein-ligand docking. In an in vitro experiment on cultures of E. coli, S. aureus and B. pumilis, 5-amino-3-(cyanomethyl)-1H-pyrazole-4-carbonitrile does not show any noticeable antibacterial effect. At the same time, three compounds of the pyrazolo[1,5-a][1,3,5]triazine series showed a pronounced antidote effect against the herbicide 2,4-D on sunflower seedlings in a laboratory experiment, for one compound a noticeable growth-stimulating effect was noted. [ABSTRACT FROM AUTHOR]

The effect of the polarity of the electrical stimulation of the external circuit of the bioelectrochemical systems, as well as the immobilization of Shewanella oneidensis MR-1 cells containing the DyP peroxidase gene on the rate of discoloration of dyes of different types, was found. For the crystal violet triphenylmethane dye, the maximum decolorization rate by suspended S. oneidensis MR-1 cells of 2.05 ± 0.07 μM/h was noted when connecting a 1.2 V direct polarity DC voltage source. One of the minimum rates was observed with reverse polarity of the connection. For cells immobilized on the anode, the rate was higher, reaching 2.91 ± 0.09 μM/h and did not decrease with increasing substrate concentration. The lowest values were also noted for the reverse connection of the voltage source. For the azo dye congo red, the maximum rate was found for a source with direct connection and an open circuit (0.26 ± 0.01 and 0.29 ± 0.02 μM/h, respectively); the minimum value was 0.11 ± 0.02 μM/h for a reverse connection. For crystal violet decolorization products, a significant decrease in the intensity of the main absorption peak at 590 nm band was found, with no notable hypsochromic shift. The qualitative changes in the decolorization product composition were indicated by the appearance, with a direct polarity of the ionistor connection, of a new absorption maximum in the region of 360 nm. The results may be of interest for the development of new methods of bioelectrochemical cleaning. [ABSTRACT FROM AUTHOR]

The level of CO2 production and the growth dynamics of the biomass of Rhodococcus erythropolis VKM Ac2017D (Russia) and the yeast strain Saccharomyces cerevisiae OenofermC2 (France) were determined in cultivation media with variously reduced (from 10 to 150 ppm) deuterium concentration. The maximum increase in the rhodococcal biomass was shown in the media with a deuterium concentration of 50 ppm or less. It was noted that the production of CO2 as an integral indicator of the biological activity of cells is more pronounced in Rhodococcus compared to the yeast. With generally similar dynamics of CO2 emission curves, prokaryotes showed broader temporal dynamics of its production. [ABSTRACT FROM AUTHOR]

The expression of ganglioside GD2 on the cell lines of colorectal adenocarcinoma HT29 and CaCo-2, as well as on the tumor tissue samples of patients with colorectal cancer was analyzed by flow cytometry. The marker was found on EpCAM-positive tumor cell samples from 6 of 12 patients but not on the HT29 and CaCo-2 cell lines. GD2 expression was not associated with a cancer stem cell subpopulation as its expression level was similar on both CD133-positive and CD133-negative tumor cells. Thus, the presence of ganglioside GD2 was found for the first time on colorectal adenocarcinoma cells. This finding opens new opportunities for targeted therapy in the treatment of this disease. [ABSTRACT FROM AUTHOR]

Metastatic prostate cancer is often associated with either primary or intractable castration-resistant prostate cancer (CRPC), thus justifying the search for entirely new ways of treatment. Oncolytic viruses are able to selectively induce the death of tumor cells without affecting normal cells. A murine Sendai virus has potential to be used as an oncolytic agent. However, tumors vary in their sensitivity to different viruses, prompting us to attempt to identify corresponding biomarkers that reflect the interaction of cancer cells and the virus. Here, we show that the sensitivity of primary prostatic adenocarcinoma cell lines to Sendai virus strain (SeVM) vary substantially. Using quantitative PCR, we evaluated expression levels of genes that encode RIG-1-like and Toll-like receptors (TLRs) in cell lines and showed that the levels of mRNAs that encode TLR3 and TLR7 correlate with a degree of sensitivity of the cells to Sendai virus. The lines with lower levels of TLR3 and TLR7 expression are more sensitive to the virus. [ABSTRACT FROM AUTHOR]

The paper presents an algorithm for quantification the degree of receptor expression to steroid hormones by automatic analysis of microscope images of immunocytochemical specimens. During experiments a high correlation between the results of the automatic analysis and visual expert assessment was shown and the possibility to apply the proposed algorithm to automate immunocytochemical analysis was confirmed. [ABSTRACT FROM AUTHOR]

Drug resistance and especially cross-resistance are the most important problems of therapy of prostate cancer. Drug resistance mechanisms, including ligand-dependent (requiring the presence of androgens in the cell) and independent (not requiring androgens) ones, are reviewed. The mechanisms are mainly based on mutations of the androgen receptor (AR) gene, expression of aberrant constitutively active AR splice variants, and upregulation of androgen synthesis genes. [ABSTRACT FROM AUTHOR]

Cell metabolic reprogramming is one of the cancer hallmarks. Glycolysis activation, along with suppression of oxidative phosphorylation and, to a lower extent, the TCA cycle, occurs in the majority of malignant tumors. A bioinformatics search for the glucose metabolism genes that are differentially expressed in colorectal cancer (CC) was performed using the data of The Cancer Genome Atlas (TCGA) Project. OGDHL for an oxoglutarate dehydrogenase complex subunit, which is involved in the TCA cycle and is indirectly responsible for the induction of apoptosis, was identified as one of the most promising candidates. A quantitative PCR analysis showed, on average, an eightfold downregulation of OGDHL in 50% (15/30) of CC samples. Based on the TCGA data, promoter hypermethylation was assumed to be a major mechanism of OGDHL inactivation. Bisulfite sequencing identified the OGDHL promoter region (+327...+767 relative to the transcription start site) that is often methylated in CC samples with downregulated ODGHL expression (80%, 8/10) and is possibly crucial for gene inactivation. Thus, frequent and significant OGDHL downregulation due to hypermethylation of a specific promoter region was demonstrated for CC. The OGDHL promoter methylation pattern was assumed to provide a marker for differential diagnosis of CIMP (CpG island methylator phenotype) tumors, which display dense hypermethylation of the promoter region in many genes. [ABSTRACT FROM AUTHOR]

The effect of water isotopic composition on the concentration of cellular biomass of oil-oxidizing actinobacteria, Rhodococcus erythropolis VKM Ac-2017D, has been observed upon cultivation in liquid nutrient media. The value of the effect was determined by experimental conditions including consecutive use of hydrophilic and hydrophobic nutrient substrates, sucrose and hexadecane. It was shown that, upon inoculation of Rhodococcus erythropolis VKM Ac-2017D cells having been cultivated in media with sucrose and deuterium content in water of 71 and 98 ppm similar in regards to mineral and isotopic composition to media containing hexadecane, a considerable increase in the production of cellular biomass was observed as compared to a control sample with water with deuterium concentration of 150 ppm being used. [ABSTRACT FROM AUTHOR]

The incubation in deuterium-depleted medium of mitochondria isolated from the liver of rats that consumed drinking diet with depleted deuterium (46 ppm) revealed a higher (by 35%) generation of hydrogen peroxide in comparison with the mitochondria (isolated from the liver of rats that consumed drinking diet with 152 ppm deuterium) incubated in medium that contained 152 ppm deuterium. Succinate addition to the reaction system led to an increase in the production of hydrogen peroxide in isolated mitochondria by 44-81%, whereas the difference in the generation of HO between the organelles incubated in mediums 46 and 152 ppm was reduced by 14%. The revealed change in the functional activity of mitochondria suggests the ability of the organism to adapt to the deuterium-depleted drinking diet, which is probably due to the formation of the D/H isotope transmembrane gradient. [ABSTRACT FROM AUTHOR]

The article discusses the parameters upon which the presence of surface-active-substances (SAS) in liquid medium is determined the values of which reveals SAS concentrations. These parameters include the surface tension (ST) and emulsifying activity (EA) which are also the main criteria of selection and measurement of microbial strains activity.