•Carrageenans modulate the synthesis of prostaglandin E2.•Carrageenans do not affect lipase activity.•Carrageenans inhibit bile acid permeation through a PAMPA membrane.•Sulfation degree is important ...for carrageenans ability to inhibit bile salts permeation.
The research described here focused on the effect of sulfated red algal polysaccharides (κ-, κ/β-, ι/κ-carrageenan) individually and in combination with lipopolysaccharide (LPS) on the synthesis of prostaglandin E2 (PGE2) and cytokines (interleukin IL-1β and IL-6) in whole blood model in vitro. The results demonstrated that, at high concentrations, carrageenans have substantial ability to modulate PGE2 synthesis and stimulate IL-1β and IL-6 synthesis. A low degree of sulfate and high molecular weight were a prerequisite for the ability of carrageenans to modulate PGE2 synthesis. Further, we investigated the ability of the carrageenans alone and in combination with casein to affect bile salt permeability through an artificial membrane imitating the gastrointestinal barrier. The least sulfated κ/β-carrageenan could retain bile salt permeation the most but less efficiently than cholestyramine. The polysaccharides did not affect pancreatic lipase activity. Our data confirm a possible mechanism of the cholesterol-reducing properties of carrageenan.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Macroaggregates are of interest because of their fast response to land management and their role in the loss or restoration of soil organic carbon (SOC). The study included two experiments. In ...Experiment I, we investigated the effect of long‐term (27 years) land management on the chemical composition of organic matter (OM) of macroaggregates. Macroaggregates were sampled from topsoil under conventional cropping, cover cropping and natural succession systems. The OM of macroaggregates from conventional cropping was more decomposed than that of cover cropping and especially natural succession, based on larger δ15N values and decomposition indices determined by multiple magic‐angle spinning nuclear magnetic resonance (13C CP/MAS NMR) and Fourier transform infrared (FTIR) spectroscopy. Previous research at the sites studied suggested that this was mainly because of reduced diversity and activity of the decomposer community, change in nutrient stoichiometry from fertilization and contrasting formation pathways of macroaggregates in conventional cropping compared with cover cropping and, specifically, natural succession. In Experiment II, we investigated the relation between OM composition and pore characteristics of macroaggregates. Macroaggregates from the natural succession system only were studied. We determined 3‐D pore‐size distribution of macroaggregates with X‐ray microtomography, for which we cut the macroaggregates into sections that had contrasting dominant pore sizes. Then, we characterized the OM of macroaggregate sections with FTIR and δ15N methods. The results showed that within a macroaggregate, the OM was less decomposed in areas where the small (13–32 µm) or large (136–260 µm) pores were abundant. This was attributed to the role of large pores in supplying fresh OM and small pores in the effective protection of OM in macroaggregates. Previous research at the site studied had shown increased abundance of large and small intra‐aggregate pores following adoption of less intensive management systems. It appears that land management can alter the OM composition of macroaggregates, partly by the regulation of OM turnover at the intra‐aggregate scale.
Highlights
OM and pore characteristics were studied in soil macroaggregates under different land management.
Long‐term intensive land management increased degree of OM decomposition in macroaggregates.
Abundance of < 32 and > 136 µm pores was positively related to less decomposed OM.
Land management may affect rate of SOM turnover by changing intra‐aggregate pore‐size distribution.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
•Red algal galactans can participate in cell surface biology involving complement system.•Polysaccharides inhibit C3 binding to LPS with direct dependence on degree of sulfation.•Degree of sulfation ...mattered in carrageenans capacity to reduce C4 binding to mannan.•C4 binding to antibodies was activated in the presence of carrageenans.•No relevant structural characteristics were observed in ameliorating C5 cleavage by plasmin.
The research described here presents data on the effect of galactans of red algae, carrageenans (λ/μ/ν-, κ-, κ/β-, and ι/κ-types), and agar on complement system activation in normal human serum. The experiments were based on well surfaces coated with triggering agents for binding initiating complement components —C3 and C4. The sulfated galactans inhibited C3 binding to lipopolysaccharide with direct dependence on the sulfation degree of polysaccharides. Sulfation degree was also important in carrageenans’ capacity to reduce C4 binding to mannan. However, C4 binding to antibodies was considerably activated by carrageenans, especially with 3,6-anhydrogalactose. The gelling carrageenans were able to block antigen binding centers of total serum IgM and with more intensity than non-gelling. No structural characteristics mattered in ameliorating C5 cleavage by plasmin in extrinsic protease complement activation, but λ/μ/ν- and κ/β-carrageenans almost completely inhibited C5 cleavage. Thus, galactans participated in cell surface biology by imitating surface glycans in inhibition of C3 binding and mannose binding lectin, but as to the tthe heclassical pathway these substances stimulated complement, probably due to their structure based on carrabiose.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The review is focused on the desulfurization of imidazolidine-2-thiones to imidazolidin-2-ones, which are widely applied in the synthesis of natural and synthetic practically useful compounds, ...primarily biologically active substances. The described methods are systematized in accordance to the key transformations, namely, nucleophilic substitution, oxidation, and more complex cascade reactions.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
One of the main limitations of capillary electrophoresis (CE) is the sorption of basic compounds on the walls of a quartz capillary. To prevent this phenomenon in CE, supporting electrolytes with ...various additives that prevent the sorption of analytes due to the formation of dynamic coatings are commonly used. Alternatively, covalent coatings, which have a number of advantages and expand the analytical capabilities of CE, are used. The main methods of the formation of coatings covalently bound to the walls of a quartz capillary are considered.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, SIK, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
PT1 peptide isolated from the venom of spider
Geolycosa
sp
.
is a modulator of P2X3 receptors that play a role in the development of inflammation and the transmission of pain impulses. The ...anti-inflammatory and analgesic efficacy of the PT1 peptide was studied in a model of complete Freund’s adjuvant-induced paw inflammation in CD-1 mice. The analgesic activity of PT1 peptide was maximum after intramuscular injection at a dose of 0.01 mg/kg, which surpassed the analgesic effect of diclofenac at a dose of 1 mg/kg. The anti-inflammatory activity was maximum after intramuscular injection at a dose of 0.0001 mg/kg; a decrease in paw thickness was observed as soon as 2 h after the administration of the PT1 peptide against the background of inflammation development. All tested doses of PT1 peptide showed high anti-inflammatory activity 4 and 24 h after administration. PT1 peptide at a dose of 0.01 mg/kg when injected intramuscularly simultaneously produced high anti-inflammatory and analgesic effects compared to other doses of the peptide. Increasing the dose of PT1 peptide led to a gradual decrease in its analgesic and anti-inflammatory activity; increasing the dose of intramuscular injection to 0.1 and 1 mg/kg is inappropriate.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
This article reveals the relevance of the development of production of clad plates and large-diameter pipes in Russia. The most widespread technologies in the world are compared. The results of the ...mathematical and physical modeling of the rolling of bimetallic packs into strips are described. The use of pack rolled clad plates is shown to be preferable for the production of large-diameter electric-welded pipes. The main production aspects of clad plates from a pack billet on a plate mill and their resulting pipes are presented.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The article discusses the construction of mathematical models for assessing economic conditions under which a positive effect of using loan capital in the implementation of innovative and investment ...projects in engineering is possible, leading to an increase in net present value (NPV). Based on the constructed models, the authors obtained economic and mathematical relations (linking the parameters of innovation and investment projects: investor profitability standard, loan capital rate, time it was entered into the financial and temporal scheme of the project, the time it began to pay off financial obligations and its duration), which determine the increase effect of NPV due to the corresponding structure of investment capital. In the form of functions of the project parameters, analytical expressions are obtained to determine the critical value of the loan rate, the time of its input, as well as the rate of return on the investor and at which the effect of an increase in the net present value of the project becomes possible. The mathematical relations and the economic conclusions drawn on their basis are backed by practical results, given in a graphic form.