Effect of red seaweed sulfated galactans on initial steps of complement activation in vitro.

The research described here presents data on the effect of galactans of red algae, carrageenans (λ/µ/ν-, κ-, κ/ß-, 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/ß-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.

Effect of carrageenans on some lipid metabolism components in vitro.

The research described here focused on the effect of sulfated red algal polysaccharides (κ-, κ/ß-, ι/κ-carrageenan) individually and in combination with lipopolysaccharide (LPS) on the synthesis of prostaglandin E2 (PGE2) and cytokines (interleukin [IL]-1ß 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-1ß 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/ß-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.

Effect of carrageenans alone and in combination with casein or lipopolysaccharide on human epithelial intestinal HT-29 cells.

The research described here was focused on the effect on human intestinal epithelial cell monolayers of sulfated red algal polysaccharides (κ-, λ-, and κ/ß-carrageenans) alone and in combination with casein or lipopolysaccharide (LPS). HT-29 cells were investigated under normal and stress conditions; stress was induced by exposure to ethanol. Cell viability was monitored with a real-time system. The change in binding properties of negatively sulfated red algal polysaccharides assessed by the measurement of free carrageenans in mixtures with casein or McCoy's 5 A culture medium by means of toluidine blue O. Low sulfate content and the presence of 3,6-anhydogalactose are prerequisites for the recovery of ethanol-exposed HT-29 cells by carrageenans. Analysis of carrageenan binding ability confirmed that casein and LPS should affect carrageenan activity. Whether the combined action of the mucin-containing layer and carrageenans or the action of carrageenans alone was responsible for enhanced cell viability under stress conditions induced by ethanol is a subject for further research. © 2017 Wiley Periodicals Inc. J Biomed Mater Res Part A: 105A: 2843-2850, 2017.

Carrageenans effect on neutrophils alone and in combination with LPS in vitro.

Influence of sulfated red algal polysaccharides (κ-, λ-, and κ/ß-carrageenans) and degraded derivative of κ/ß-carrageenan on neutrophils/monocytes activation alone and in combination with lipopolysaccharide was investigated by means of determination of reactive oxygen species production, latex microparticles engulfment, total and extracellular myeloperoxidase induction and the analysis of silhouette and contour two-dimensional images of flattened cells. Carrageenans alone can activate neutrophils with much less potency than lipopolysaccharide (LPS) and the sulfation degree of carrageenans stipulates high activity in this role. On the other hand, carrageenans especially with low contents of sulfate groups are able to interfere with LPS in vitro resulting in reducing inter- and intracellular activation of neutrophils killing mechanisms. Further research is necessary to relate these findings to actions on the whole animal or human in vivo. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 1603-1609, 2016.

The supramolecular structure of LPS-chitosan complexes of varied composition in relation to their biological activity.

The complexes of chitosan (Ch) with lipopolysaccharides (LPSs) from Escherichia coli O55:B5 (E-LPS) and Yersinia pseudotuberculosis 1B 598 (Y-LPS) of various weight compositions were investigated using quasi-elastic light scattering, ζ-potential distribution assay and atomic force microscopy. The alteration of ζ-potential of E-LPS-Ch complexes from negative to positive values depending on Ch content was detected. The Y-LPS-Ch complexes had similar positive ζ-potentials regardless of Ch content. The transformation of the supramolecular structure of E-LPS after binding with to Ch was revealed. Screening of E-LPS and Y-LPS particles by Ch in the complexes with high polycation was detected. The ability of LPS-Ch complex to induce biosynthesis of TNF-α and reactive oxygen species in stimulated human mononuclear cells was studied. A significant decrease in activity complexes compared to that of the initial LPS was observed only for E-LPS-Ch complexes.

[STUDY OF THE ROLE OF INNATE IMMUNITY FACTORS (TLR2, HBD-2, TNF-α, TGF-ß) IN PERIODONTITIS PATHOGENESIS].

AIM: Study of the role of innate immunity factors, namely, expression of TLR2 and HBD-2 genes, as well as TNF-α arid TGF-ß in pathogenesis of periodontium tissue inflammation. MATERIALS AND METHODS: 59 individuals with periodontitis illnesses were included into the study; 15 healthy donors represented the comparison group. Study of the TLR2 and HBD-2 gene expression levels was carried out by rRT-PCR, cytokine production evaluation--by EIA. RESULTS: The results of the study have shown the presence of TLR-mediated disbalance in the innate immunity system in the periodontium tissue during chronic generalized periodontitis. TLR2 gene hyperexpression was accompanied by the reduction of expression of anti-microbial peptide HBD-2, as well as an increase of production of TNF-αand TGF-P by epithelial cells of periodontium mucosa. Conclusion.-The study carried out has shown that disturbance of molecular mechanisms of innate immunity system has an important place in pathogenesis of periodontitis. -

[HIV infection risk perception and stigmatizing attitude: Results of surveys of dwellers from the Central Administrative District of Moscow].

AIM: To study human immunodeficiency virus (HIV) infection risk perception and stigmatizing attitudes in the dwellers of the Central Administrative District of Moscow. SUBJECTS AND METHODS: An anonymous survey was conducted using specially developed questionnaires. A total of 893 people were interviewed. Each of the given indicators was used to ask 98 to 254 respondents. Among the survey participants, there were 92 healthcare workers, including 66 physicians and 26 representatives of middle-level and junior medical staff. According to their replies, the respondents were divided into 2 groups: 1) healthcare workers; 2) representatives of the so-called general population. RESULTS: 91.3% of the healthcare workers gave a negative reply to the question: "Should contacts (intercourse) with people living with HIV (AIDS) be avoided to escape infection?". In Group 2, 58.8 and 23.5% of the respondents answered negatively and positively, respectively; and 17.6% had difficulty answering the question. In the general population group, 44.10% of the respondents answered negatively and 32.2% had difficulty answering the question: "Would you agree to live in the same room with anybody whom you know or suspect to be HIV positive?"; 23.8% agreed to do this. Among the healthcare workers, there were 46.7% of the respondents who answered positively. When the question: "Would you agree to send your child (grandson) to the kindergarten if you would learn that a HIV-infected child goes there?" was asked, 48.6 and 18.7% of the respondents in the general population group answered negatively and positively, respectively; 32.7% had difficulty answering. In the group of healthcare workers, 66.7% answered positively. Among both the healthcare workers and the representatives of the general population, more than 60% of the respondents agreed with the statement that "HIV-infected people lead a loose life". CONCLUSION: The specific features of perceiving a HIV infection risk and showing stigmatizing attitudes towards HIV-infected patients make the forming less dangerous behaviors difficult and restrict an access to care and support in infected patients. The training of healthcare workers in issues related to HIV infection should involve the identification of stigmatizing attitudes and the application of destigmatization strategies.

[Awareness of the issues of HIV infection in the dwellers of the Central Administrative District of Moscow].

AIM: To study the awareness of HIV infection in the dwellers of the Central Administrative District of Moscow. SUBJECTS AND METHODS: A continuous cross-sectional survey was made in all the citizens who applied to the V.A. Gilyarovsky Mental Hospital Three, Branch Four, for information on the day of the survey and gave their consent to participate in this survey that was performed in 4 steps; a total of 414 persons were questioned. Their knowledge and ideas were anonymously assessed using a specially developed questionnaire. After analyzing their replies, the respondents were divided into 3 groups: 1) representatives of the so-called general population; 2) draft-age youngsters; 3) health care workers. RESULTS: The draftees (34%) gave the largest number of wrong answers to the question whether human immunodeficiency virus (HIV) could be transmitted through mosquito bites (p=0.0001). Among the healthcare workers, 81% of the respondents indicated that HIV could not be transmitted through mosquito bites; the proportion of right answers among the general population was 64.3%. The statement that a condom reliably protects against HIV infection was considered to be true by 52.4% of the health care workers, 56% of the draftees, and 62.2% of the representatives of the general population. The HIV/AIDS topic was not relevant for 43.4% of the general population and 58.3% of the health care workers; 98.7% of the respondents of the general population pointed that blood should be sampled for testing for HIV antibodies to find out whether a person had HIV (AIDS); this answer was chosen by 87.5% of the surveyed health care workers. CONCLUSION: Low knowledge about HIV infection particularly among the draft-age youngsters is evidence for the insufficient efficiency of performed preventive measures among both the general population and the organized young people. Attention is drawn to the opinion of the respondent health care workers as to the reliability of using the condom to prevent HIV transmission. The findings will be kept in mind when elaborating the teaching programs.

Polysaccharide structure of tetrasporic red seaweed Tichocarpus crinitus.

Sulfated polysaccharide isolated from tetrasporic plants of Tichocarpus crinitus was investigated. The polysaccharide was isolated by two methods: with water extraction at 80 °C (HT) and with a mild alkaline extraction (AE). The extracted polysaccharides were presented by non-gelling ones only, while galactose and 3,6-AG were the main monosaccharides, at the same time amount of 3,6-AG in AE polysaccharides was the similar to that of HT. According to methods of spectroscopy and mass spectrometry, the polysaccharide from tetrasporic T. crinitus contains main blocks of 1,3-linked ß-D-galactopyranosyl-2,4-disulfates and 1,4-linked 3,6-anhydro-α-D-galactopyranosyl while 6-sulfated 4-linked galactopyranosyl resudies are randomly distributed along the polysaccharide chain. The alkaline treatment of HT polysaccharide results in obtaining polysaccharide with regular structure that composed of alternating 1,3-linked ß-D-galactopyranosyl-2,4-disulfates and 1,4-linked 3,6-anhydro-α-D-galactopyranosyl residues. Native polysaccharide (HT) possessed both high anticoagulant and antiplatelet activity measured by fibrin clotting and platelet aggregation induced by collagen. This activity could be connected with peculiar chemical structure of HT polysaccharide which has high sulfation degree and contains also 3,6-anhydrogalactose in the polymer chain.

Atomic force microscopy imaging of carrageenans from red algae of Gigartinaceae and Tichocarpaceae families.

In the present article, the atomic force microscopy was applied to investigate macromolecular structures of various carrageenan types including hybrid polysaccharides (κ-, κ/ß-, κ/ι-, λ-, and X-carrageenans) depending on polysaccharide concentration. The structures dependence on a polysaccharide concentration also was focused. κ-Carrageenan forms both single and two stranded structures at a low concentration. At high concentrations κ-, κ/ß-, and κ/ι-carrageenans form fibrous network-like structures by a side-by-side association type at the same time for κ/ι-carrageenan end-to-end association type also was found. Comparably to κ-carrageenan, κ/ß-carrageenan network was more open with coarser fibers while κ/ι-carrageenan structure is characterized with a more flexible network. Honeycombed structures due to end-to-end and side-by-side association types were observed for X-carrageenan, while λ-carrageenan formed honeycombed structures only at high concentrations. In order to investigate topographical parameters of the carrageenans macromolecular structure a new method of the autocorrelation function analysis was used for the first time.

In vitro and ex vivo studies of antioxidant activity of carrageenans, sulfated polysaccharides from red algae.

Antioxidant properties of structurally different sulfated polysaccharides (carrageenans) were studied in vitro and ex vivo. Ferric reducing antioxidant activity of carrageenans and their inhibitory effects on hydroxyl radicals and superoxide anion radicals were demonstrated in vitro. Activity of carrageenans depends on the polysaccharide structure. Carrageenans stimulate catalytic activity of SOD from donor erythrocyte.

[Regulatory effect of complex of natural cytokines and antimicrobial peptides on murine macrophages infected with multidrug-resistant Mycobacterium tuberculosis].

AIM: To study the effect of complex of natural cytokines and antimicrobial peptides (CNCAP) included in preparation Superlymph on growth of multidrug-resistant Mycobacterium tuberculosis CN-37 on the modem of murine peritoneal macrophages (MPh) cultivated in vitro. MATERIALS AND METHODS: Effect of CNCAP on peritoneal MPh of tuberculosis-susceptible mice C57BL/6 infected by M. tuberculosis CN-37 was studied using ex vivo model. Macrophages were preliminary incubated with CNCAP during one day. M. tuberculosis growth was assessed on 7th day by PCR. RESULTS: Preliminary incubation of infected MPh with CNCAP resulted in inhibition of M. tuberculosis CN-37 growth. CONCLUSION: Superlymph activates macrophages which lead to enhanced bactericidal action of MPh on M. tuberculosis CN-37.

[Use of PCR for detection of maize seeds infected with the fungus Fusarium moniliforme Sheldon var.lactis]. / Ispol'zovanie polimeraznoi tsepnoi reaktsii dlia detektsii zagriazneniia zerna kukuruzy gribom Fusarium moniliforme Sheldon.

The procedure of the PCR for the detection of Fusarium moniliforme Sheldon var. lactis on the maize seeds has been elaborated. The based on a highly sensitive molecular genetics technology method of fungal pathogen detection allows to reveal its presence before the visual symptoms of seed damage.

[Screening of alpha-N-acetylgalactosaminidase producers among microorganisms of different taxonomic groups]. / Skrining produtsentof al'fa-N-atsetilgalaktozaminidazy sredi mikroorganizmov razlichnykh taksonomicheskikh grupp.

Screening of producers of alpha-N-acetylgalactosaminidase among 854 strains of micromycetes, 171 yeast and 357 bacterial cultures has been carried out. A capacity to synthesize the enzyme was revealed in 11% of cultures. Representatives of Aspergillus genus (activity--0.11-0.142 un./ml) were most active in producing the enzyme. It has been established that glucosidases spectrum in the culture liquid of 18 most active strains was characterized by complete homogeneity and by the presence of a rather high level (0.5-0.9 un./ml) of alpha-galactosidase activity. Complex preparations of alpha-N-acetylgalactosaminidase and alpha-galactosidase have been obtained from the culture liquid of producers by fractionation by ammonium sulphate (30 and 90% saturation); their pH- and thermo-optimum, pH- and thermal stability have been studied. It was shown possibility to induce alpha-N-acetylgalactosaminidase synthesis by a number of carbohydrates (galactose, glucose, galactosamine, and glucosamine), complex-forming substances (guanidine HCl), nitroaminoguanidin and guanidine carbonate and bovine blood. As a result the strain of Aspergillus niger 185 III was chosen which activity level could be increased more than 3 times (activity--0.6 un./ml as compared to initial one).

[The pharmacodynamic and pharmacokinetic characteristics of furosemide and furesis]. / Osobennosti farmakodinamiki i farmakokinetiki furosemida i furezisa.

The object of the work was comparative study of the special features of the pharmacodynamic and pharmacokinetic properties of the diuretics furosemide and furesis in an ambulant regimen with the subject lying in an antiorthostatic position. Six practically healthy males were examined. They were given per os either 40 mg furosemide or one tablet of furesis (49 mg furosemide and 50 mg triamterine). Blood from the vein and urine were repeatedly tested.