P-selectin blocking potency of multimeric tyrosine sulfates in vitro and in vivo

P-selectin blocking potency was investigated using synthetic monomeric and polymeric anionic compounds containing sulfate groups such as O-sulfotyrosine (sTyr) and/or sulfated Lewis structures. A non-carbohydrate-containing polyacrylamide conjugate sTyr-PAA (80% mol of sTyr) was a remarkably potent inhibitor of P-selectin binding in vitro, having an IC(50) value of 6 ng/mL (equivalent to 10 nM calculated on the basis of sTyr residues or 0.1 nM calculated by the mass of the macromolecule). The inhibitory effect of sTyr-PAA (80%) towards P-selectin is significantly greater than that of fucoidan (IC(50), 100 ng/mL). However, sTyr-PAA (80%) was less effective than fucoidan at reducing neutrophil extravasation in an in vivo rat model of peritonitis.

[Cellulose decomposition under nitrogen deficiency by bacteria isolated from the intestines of phytophagous vertebrates]

A nitrogen-fixing strain identified as Klebsiella pneumonia 402-2 and two endoglucanase-synthesizing Bacillus strains were isolated from the intestines of phytophagous animals. One of the Bacillus strains was identified as Bacillus subtilis GL. Klebsiella pneumoniae 402-2 increased the endoglucanase activity of both Bacillus strains in mixed cultures. The data on the taxonomic position of strains 402-2 and GL and on the nitrogen-fixing capacity of strain 402-2 were confirmed by sequencing and analyzing their 16S rRNA genes and by amplifying the nitrogenase gene nifH.

Uncharged P-selectin blockers

The blocking potency of P- and L-selectin was studied for certain small molecule mannosides and their polyacrylamide (PAA, 30 kDa) conjugates in comparison to SiaLe(x) and fucoidan. Two experimental systems were used: (1) solid phase static assay based on recombinant selectins, and (2) P-selectin dependent rat peritoneal inflammation. betaMan-SC6H4NO2- p was four times more potent P-selectin inhibitor as compared to SiaLe(x). Docking of this molecule onto the P-selectin carbohydrate-binding site demonstrated that a nitro group enabled an electrostatic interaction with residue Lys 84, while the phenyl ring and the CH2 at C-6 contacted the CH2 groups of the same Lys residue. In vivo, betaMan-SC6H4NO2- p blocked experimental inflammation better than SiaLe(x), but significantly lower than fucoidan. In vitro Man-polyacrylic acid conjugates appeared to be very potent inhibitors comparable to fucoidan, uncharged Man-PAA proved rather active, comparable to SiaLe(x)-PAA both in vitro, and in vivo, whereas mannan did not display any P-selectin blocking effect.

[Effects of mannose derivatives on development of selectin-dependent peritoneal inflammation in rats and mice]

The inhibitory effect of mannose-containing oligosaccharides on model carbohydrate ligand interaction with E-, P- and L-selectins in vitro, as well as on the ability of these compounds to block the leukocyte extravasation in rat and mouse peritonitis in vivo was studied. The monomeric and polymeric compounds, 4-nitrophenylthiomannoside, phenylmannoside, conjugated with polyacrylic acid, and alpha-mannose, conjugated with polyacrylamide, inhibited the binding of the model ligand to P- and L-selectins (but not to E-selectin). Intravenous injection of these compounds was found to cause a dose-dependent reduction of neutrophil accumulation in rat peritoneum. The polysaccharide mannan was inactive in both types of experiments. The conjugate of phenylmannoside with polyacrylic acid was the most effective blocker as in vitro experiments, as well as in vivo. The inhibitory effect of subcutaneous injection of 4-nitrophenylthiomannoside on mouse peritonitis was demonstrated.

[Nitrogen requirements of Microtus rossiaemeridionalis]

Total nitrogen requirements in the small herbivorous rodent Microtus rossiaemeridionalis were studied. When provided with two kinds of standard laboratory food (about 20 and 0% digestible protein, respectively) ad libitum (cafeteria diet), the voles chose a diet of 14% protein. The total daily (with urine and faeces) nitrogen losses were, in this case, determined as 3.65 +/- 0. 60 mg N/g of body mass. When provided with a protein-free diet alone, the animals lost 0.90 +/- 0.05 mg N/g body mass per day, comprising about 3% of their body mass daily. It was proposed that the consumption of a low-fiber diet (about 4% in both kinds of food) could affect the gastrointestinal bacterial flora and, thus, lead to changes in the primarily herbivorous nitrogen metabolism.

[Nitrogen fixation--new fenomenon in rodent feeding]

We have conducted a series of experiments in order to test hypothesis about the possible use of nitrogen fixation by small phytophagous mammals as a way to supplement their nitrogen balance. Two groups of red voles Clethrionomys rutilis were kept on rations with different protein nitrogen content. Three days later, the rate of nitrogen fixation was determined in different regions of the digestive tract. Nitrogen-fixing activity has been detected in the GI tract of all studied voles, specifically in those regions, where symbiocenoses were present; it was particularly high in animals of the experimental group under the conditions of dietary nitrogen limitation. A mixed culture of bacteria capable of nitrogen fixation has been isolated from the digestive tract of red voles.

[Analysis of various taxon specific parameters of the guard hair cuticles for development of the mammalian identification system by morphometric characteristics of their hair]

Mathematical indices of the structure of the external surface of guard hairs have been developed on the basis of a KS300 system of automatic image analysis (Kontrom Elektronik, Germany), which are capable of serving, in some cases, as diagnostic parameters of large taxa (order, family). The guard hair morphology is affected by various factors, such as body region where a given hair is located, season, diet, sex of individual, and state of its health, which is expressed in changes of some morphometric data. For a more complete analysis of the characteristics of the guard hair structure, it is necessary to use indices that describe the macro- and microstructure of the external surface of the stem and its internal structure.

Adaptation to salt stress in a salt-tolerant strain of the yeast Yarrowia lipolytica

We have studied the cellular mechanisms underlying adaptation to salt stress in a newly isolated osmo- and salt-tolerant strain of the yeast Yarrowia lipolytica. When cells are incubated in the presence of 9% NaCl, a rapid change in their size and shape is observed. Salt stress is accompanied by an increase in the intracellular level of glycerol, free amino acids (notably proline and aliphatic amino acids), and Na+, as well as by changes in lipid and fatty acid composition.

[Inhibitory activity of monomeric and polymeric selectin ligands]

The ability of tetrasaccharides (SiaLex, SiaLea, HSO3Lex), their conjugates with polyacrylamide (40 kDa), and several other monomeric and polymeric substances to block selectins has been compared with that of polysaccaride fucoidan. Two assay systems were used: one was constructed on the base of recombinant E-, P-, and L-selectins; the other was a rat model of peritoneal inflammation. IC50 values for the neoglycoconjugate SiaLea-PAA were 6, 40, and 85 microM with the recombinant E-, P-, and L-selectins, respectively; all monomeric inhibitors were about two orders of magnitude weaker. PAA-conjugates, containing as a ligand tyrosine-o-sulfate in addition to one of the above mentioned oligosaccharides, were the most potent synthetic blockers. Compared with the most potent of the known inhibitors, fucoidan, bi-ligand glycoconjugate HSO3Lea-PAA-sTyr, displayed in vitro similar activity in blocking L-selectin, while its activity towards P-selectin was ten times lower. All the synthetic polymers tested were able to inhibit neutrophil extravasation to inflammation site, acting in concentration about 10 mg/kg. Thus, the effect of SiaLex is considerably more effective in vivo than in vitro, whereas heavily charged fucoidan and bi-ligand neoglycoconjugate acted in converse manner.

[Development of microbiological technology of air deodoration in laboratory-industrial conditions using a pilot plant]

Laboratory tests were performed to select a complex of bacterial strains capable of effective deodoration of waste air produced by an animal formulated feed works under elevated temperature with the presence of numerous organic pollutants. The complex included species from the general Nocardia, Rhodococcus, and Comamonas. The biocatalyst was tested in a real industrial process with the use of a pilot plant for microbiological deodoration of waste air. The test lasted for over six months and confirmed the efficiency of the development method of deodoration.

[Sulfated polysaccharides as inhibitors of receptor activity of P-selectin and P-selectin-dependent inflammation]

The inhibitory effects of sulfated polysaccharides-fucoidan and heparin on P-selectin-ligand interaction in vitro and on the ability of fucoidan to inhibit the leukocyte extravasation in rat peritonitis were studied. The lectin activity of P-selectin in vitro was based on its ability to bind lectin-labeled synthetic ligand, Sialyl-Lea/x, conjugated with polyacrylamide (PAA). Fucoidan and heparin inhibited binding of labeled ligand to both purified P-selectin and the activated platelets expressing P-selectin on their surface. The inhibitory effect of fucoidan 100-fold higher than that of heparin. As P-selectin plays an important role at an earlier stage of the inflammation process, the antiinflammatory action of fucoidan on P-selectin-dependent peritonitis in rats was studied. Peritonitis was induced by intraperitoneal injection of the peptone solution and was characterized by an increase in total cell number and neutrophil percentage in rat peritone exudate. Intravenous injection of fucoidan was found to cause a dose- and time-dependent reduction of neutrophil extravasation into inflamed peritoneum. The minimal dose of fucoidan, that was able to produce 96.8 +/- 2.9% inhibition of neutrophil extravasation--if administered within the first 15 min after peptone-B was 0.8 mg per rat. Significant effect of fucoidan injection (about 80% inhibition) was also obtained 1.5 h after the induction of inflammation. Fucoidan administered 2.5 h after peptone had virtually no effect on neutrophil extravasation. The data obtained show that fucoidan blocks the inflammation process at its earlier stages--most probably at the expense of its interaction with P-selectin.

Fucoidan inhibits leukocyte recruitment in a model peritoneal inflammation in rat and blocks interaction of P-selectin with its carbohydrate ligand

Neutrophil recruitment into systemic inflammatory sites in vivo is thought to be initiated by selectin-mediated endothelial adherence. The effect of fucoidan (natural sulfated polymer of L-fucose) on the selectin dependent PMN migration into rat peritoneum following the induction of inflammation by peptone injection was studied. Peritonitis was characterized by an increase in the total cell number (from 45.3 x 10(6) to 91.6 x 10(6)/rat), and by highly elevated PMN content (from 0.2% to 58%) in the rat peritoneal cavity 3 h after peptone injection. Intravenous administration of fucoidan was found to reduce, in a dose-dependent manner, neutrophil migration into peritoneum. Fucoidan in a dose as low as 0.8 mg per rat caused 96.8% reduction of neutrophil extravasation. The inhibitory effect of fucoidan was also dependent on the time intervals between the peptone and fucoidan injections. The maximal inhibitory effect of fucoidan was observed within the first 15 min after the induction of peritonitis and it was maintained at a level of 80% during 1.5 h. Administration of fucoidan 2.5 h after peptone injection had practically no effect on PMN extravasation. Since P-selectin is known to play a key role at the earlier stages of PMN extravasation, it was suggested that the inhibitory effect of fucoidan was mostly due to its interaction with P-selectin. The in vitro experiments demonstrated the high affinity of fucoidan for both isolated P-selectin and P-selectin in plasma membranes of activated platelets.

[Change of isoforms' spectrum of alpha-L-fucoside secreted by affected cells in some hereditary lysosomal diseases]

In vitro it was studied the isoform spectra of the intracellular and secreted alpha-L-fucosidase from skin fibroblasts of patients with Fabry disease (glycolipidosis), Hurler and Sanfilippo D diseases (mucopolysaccharodosis, types I and III) and in the normal state was studied. It was shown that the multiple form profile of secreted alpha-L-fucosidase in patients fibroblasts was changed as compared to that in control: the pathological cells were characterized by expression of more basic isoforms of alpha-L-fucosidase. The changes were similar to those in sucrose-loaded normal cells, modelling storage disease. The data obtained allow the suggestion that the intracellular accumulation of compounds whose hydrolysis was disturbed on a hereditary deficiency of enumerated glycosidases can influence the posttranslational processing of alpha-L-fucosidase, the enzyme which is not primary affected in these disorders. These data allow the conclusion that the high phenotypic heterogenity of lysosomic storage diseases is possibly due to the influence of so-called epigenetic factors involving the changes in properties of such glycosidases as are not associated with a primary hereditary defect.

[The structure of the skin of the external auditory canal and the antiviral activity of the cerumen in carnivorous mammals]

The structure of the meatus acusticus externus skin was studied in the sable, mink, and European polecat with a parallel estimation of antiherpetic activity of the cerumen. Morphologically, these species differ in the degree of fat cellulose development, vascularization, and association with the lymphoid tissue. Lymphocytes are present both in the tissue and along the skin gland ducts and hair follicles up to the external surface only in the sable. The cerumen samples have antiviral activity also in the sable alone. The relationship between physiological properties of the mammalian cerumen and morphogenetic features is discussed.

[The anti-infective properties of mammalian earwax]

The cerumen (earwax) of some mammals possesses antistaphylococcal, antimicrococcal and antiherpes activities. The cerumen of two thirds of individuals, irrespective of their species identity and sex, has antiviral properties. The mean chemotherapeutical index in the studied groups follows a significantly decreasing sequence: dogs, humans without signs of herpes infections, rabbits, and humans with clinically expressed herpes infection. Cerumen of almost 25% of humans of the compared groups displays the immunostimulating activity. The cerumen of all studied individuals contains yeast-like fungi. A suggestion is put forward that the products of their metabolism stimulate local release of interferon-like substances by the lymphoid tissue in the cerumen.

Lysosomal glycosidases in different populations of human thymocytes

Lysosomal glycosidase activities were studied in human thymocyte fractions obtained by two methods: (A) fractionation in Percoll density gradient and (B) separation from the cells forming rosettes with sheep erythrocytes (E-RFC). (A) affords fraction L, enriched with immature and endogenously activated thymocytes, and fraction H containing mature thymocytes. By use of (B), fraction E-RFC--enriched with non-activated immature thymocytes--was obtained. Comparative study of E-RFC and H revealed diverse alterations in activities of glycosidases during thymocytes maturation, specifically decreases in alpha-L-fucosidase and alpha-D-mannosidase and an increase in beta-D-galactosidase. Comparing E-RFC and L demonstrates increases in activities of studied glycosidases following endogenous activation of thymocytes.

[Bacteria in the secretion of auxiliary sacs in the opening of the cheek pouches in Campbell hamsters]

A specific and balanced bacterial community exists in the secrete of auxiliary sacs (AS) in the opening of buccal pockets of Campbell hamsters. Parents pass these bacteria to the progeny through certain forms of their social behavior. The bacterial community forms in babies by the 20th day, i.e. when they are abandoned by parents and start independent existence. A composition of the bacterial community in the AS secrete is independent of the host sex; however, it depends on the physiological state of the host organism, e.g. it changes during lactation. A removal of the AS secrete, containing bacteria, has adverse effects on the hamster physiology: it causes intestine dysbacteriosis, active propagation of Protozoa and parasitic worms. The lack of a normal microbial community in the AS of babies, who did not get the AS secrete from their parents, has analogous consequences.

[The participation of vaginal bacteria in Phodopus campbelli in the chemical communication between male and female]

Phodopus campbelli commonly occurs in dry steppe and semidesert zone of south Siberia, Mongolia and China. Using radiotelemetry we found that a male has to cover about 2 km from his burrow to encounter a receptive female. Female in estrus marks a small area around its burrow by vaginal smear. Experiments were carried out in laboratory to discover the nature of this strong signal. In a "open field" area four boxes within stimuli we recorded the time complemented spent by males near boxes to study the attractive effect of intact receptive female, germ culture of vaginal smear and artificial mixed culture of bacteria which were found in the vaginal smear of Ph. campbelli receptive female. Males (n = 15) spent significantly more time near the boxes with female in estrus or day before estrus as compared with two other days of cycle. Germ culture from vaginal smear sampled on the estrus day was more attractive to males on 6th day than on the 2, -3, -5, -7, -8--or 9th days of cultivation, pure culture or germ culture sampled on anestrus. Mixed culture, which simulated the proportion of predominant bacteria in the estrus vaginal smear, was significantly more attractive for males on the 3rd day of cultivation. Thus sexual attractant of Ph. campbelli could be produced by some bacteria located in the vagina in estrus and it takes a couple of days of cultivation for maximum attractive effect.

Isoform patterns of lysosomal glycosidases in phenotypically different leukemic lymphoid cells

Isoform patterns of six lysosomal glycosidases were studied in leukemic lymphoid cells phenotypically related to B and T cells at distinct stages of differentiation. In all types of cells, the activity of glycosidases under study was expressed in two major isoforms. No correlation was observed between isoform patterns and cell phenotypes. The beta-hexosaminidase isoform ratios for phenotypically related leukemic lymphoid cells but isolated from different sources (blood and spleen) differed. It was suggested that cell localization affects isoform expression. An anomalous alpha-mannosidase was detected in lymphoid cells from lymph nodes, while it was lacking in the phenotypically related blood lymphoid cells from the same patients. Isoform I of beta-hexosaminidase was recorded in lymphoid cells of patients with anemias.

[The interaction between bacteria and the surface of the skin and hair in mammals]

There is a certain equilibrium between the organism and the bacteria on the surface of the animal's skin, which depends on the structure and physicochemical properties of the external cover. The structure of cuticular scale of the rabbit hair and the number of bacteria on it are related to the physiological condition of the animal. In diseased rabbits the relief of the hair surface becomes more complicated, the number of bacteria uniformly distributing along the hair stem increases and the capacity of the hair for adhesion of new bacteria is enhanced. Stimulation of non-specific immunity of animals leads to smoothing of the scale surface, uniform disappearance of bacteria and decreased adhesion of new microorganisms. The cuticle structure and adhesive properties of the hair can be used as criteria for assessing certain influences on the organism.

Acidic alpha-D-mannosidase in phenotypically different leukemic lymphoid cells

The activity of acid alpha-mannosidase in phenotypically characterized lymphoid cells, isolated from peripheral blood, spleen and lymph nodes of patients with various lymphoproliferative disorders has been studied. Cells with different immunophenotypes were shown to have different alpha-mannosidase activity levels. The lowest alpha-mannosidase activity was observed in cells phenotypically corresponding to early B cells obtained from B-CLL patients. The highest activity was determined in cells with phenotypes of activated, CD11c-expressing B cells from B-NHL and HCL patients. There were considerable differences in alpha-mannosidase activity between peripheral blood and spleen lymphoid cells of B-NHL patients with spleen damage. The data obtained may be used in classification, primary diagnosis and staging of hematopoietic malignancies.

[Lymphoid cell glycosidases in various forms of lymphoproliferative disorders]

Activity of 8 glycosidases (6 acid lysosomal and 2 neutral cytosolic enzymes) was estimated in lymphoid cells of 28 patients with different forms of lymphoproliferative disorders: B- and T-chronic lymphocytic leukemia (CLL), non-Hodgkins lymphoma (NHL), Sezary syndrome, hairy cell leukemia (HCL) and B- and T-acute lymphoblastic leukemia (ALL). Activity of these glycosidases was also studied in mononuclear cells and granulocytes of healthy volunteers and in immature myeloid cells of 16 patients with chronic myeloid leukemia (CML). In lymphoid cells of all the patients studied (except of ALL) the glycosidases activity was decreased as compared with that of normal mononuclear cells and immature myeloid cells. Activity of the majority enzymes studied was higher in T-lymphoid cells of patients with lymphoproliferative disorders as compared with B-cells. The highest glycosidases activity was found in ALL cells and the lowest--in CLL cells of the patients with B-lymphoid cells forms of the disease. Activities of N-acetyl-beta-D-hexosaminidase, alpha-D-mannosidase and beta-D-glucuronidase were distinctly dissimilar in cells of the patients with B-CLL, B-NHL and HCL. Estimation of these glycosidases activity in lymphoid cells may be of importance in differential diagnosis of lymphoproliferative disorders.

[The dynamics of the bacterial associations in the vaginal mucus of female Syrian hamsters during the sexual cycle]

Autofluctuations in the numbers of bacteria, leukocytes and epithelial cells were observed in the vaginal secretion of Syrian female hamsters. The amplitude of fluctuations depended both on individual features of females and on environmental factors like light conditions. It was suggested that vaginal bacteria perform functions of a stimulator for local immunity to protect against infections and play a sanitary role to eliminate epithelial cells and remains of spermatozoids. A case is possible that products of the bacterium vital activity contribute also to the formation of female sex pheromone.

[Neutral alpha-mannosidase in human B- and T-lymphoid cells]

The presence of neutral alpha-mannosidase activity in normal and pathological lymphoid cells has been demonstrated. The specific activities of the enzyme in different cell types were similar with the exception of B-cells from B-CLL patients when it was a little higher. The activity of acid alpha-mannosidase was also determined in these lymphoid cells. The neutral to acid alpha-mannosidase activity ratio was different in B- and T-cells: in the former neutral alpha-mannosidase activity prevailed, whereas in the latter the predominance of acid alpha-mannosidase activity was apparent. Neutral alpha-mannosidases from pathological B- and T-cells were partially purified and their properties were investigated. In both cell types the enzyme was localized in the cytosol, was very labile and could be stabilized with Mn2+ and dithiothreitol. The enzyme was activated by Co2+ and inhibited by Zn2+ and EDTA. Swainsonine inhibited the B-cell neutral alpha-mannosidase somewhat more strongly in comparison with the T-cell enzyme.