Assessment of heavy metals leachability from metallo-organic sorbent-iron humate-with the aid of sequential extraction test.

The sequential extraction test, known as a BCR procedure, was used to assess a leachability of heavy metals (Zn, Cd, Pb, Cu) from the metallo-organic sorbent-iron humate-loaded with these metals. The sequential test allowed to discriminate between various fractions of heavy metals, namely the acid-extractable fraction, the fraction bound to Fe oxides, and the fraction bound to organic matter. It was proven that the heavy metals are bound mainly to Fe oxides and organic matter, and thus they may be relatively hardly liberated into the environment.

Removal of basic (Methylene Blue) and acid (Egacid Orange) dyes from waters by sorption on chemically treated wood shavings.

Spruce wood shavings from Picea abies were used for an adsorptive removal of both basic as well as acid dyes from waters. The sorption properties of the sorbents were modified with HCl, Na(2)CO(3) and Na(2)HPO(4). The treatment of the wood sorbents with alkaline carbonate solution as well as with phosphate solution increased the sorption ability for the basic dye (Methylene Blue), whereas the treatment with mineral acid decreased the sorption ability for Methylene Blue to some extent.

Hydrogen-bonded nucleic acid base pairs containing unusual base tautomers: complete basis set calculations at the MP2 and CCSD(T) levels.

The total interaction energies of altogether 15 hydrogen-bonded nucleic acid base pairs containing unusual base tautomers were calculated. The geometry properties of all selected adenine-thymine and guanine-cytosine hydrogen-bonded base pairs enable their incorporation into DNA. Unusual base pairing patterns were compared with Watson-Crick H-bonded structures of the adenine-thymine and guanine-cytosine pairs.

Iron humate as a low-cost sorbent for metal ions.

Iron humate produced as a waste by-product during an industrial manufacture of humic substances from low-rank brown coals was tested as a sorbent for the removal of metal cations--Cd (II), Cu (II), Co (II), Ni (II), Zn (II), TI (I), Eu (III), Cr (III)--as well as hexavalent chromium from waters. The Langmuir-type isotherms were used to describe the metal sorption; the respective equations may be derived and interpreted on the basis of a concept of surface-complexation reactions. Parameters of the sorption isotherms were estimated from experimental dependencies measured in a batch arrangement.

Correlated ab initio study of nucleic acid bases and their tautomers in the gas phase, in a microhydrated environment and in aqueous solution. Part 4. Uracil and thymine.

Altogether 13 keto and enol tautomers of uracil and 13 keto and enol tautomers of thymine were studied theoretically in the gas phase, in a microhydrated environment (1 and 2 water molecules) and in a water environment. Bulk water was described using the thermodynamic integration method, Conductor-like polarizable continuum model (C-PCM, COSMO) and hybrid model (C-PCM + 1-2 explicit water molecules). The structures of various tautomers were determined at the RI-MP2 level using the TZVPP basis set while relative energies were determined at the CCSD(T) level.

The fate of protein antigen in earthworms: study in vivo.

Parenteral administration of antigen induces in the earthworms Lumbricus terrestris and Eisenia foetida the formation of antigen-binding protein. Labelled antigen was efficiently digested in the coelomic fluids of both species since the total amount of radioactivity in the coelomic fluids decreased. Antigen internalized in the free coelomocytes of both species was present in a TCA-precipitable form, although the decline of total radioactivity was higher than in the coelomic fluid, indicating that the TCA-nonprecipitable fragments are rapidly released from coelomocytes into the coelomic fluid.

The fate of protein antigen in earthworms: study in vitro.

Earthworm coelomocytes digest protein antigen in vitro. Proteolytic activity was detected both in cell-free coelomic fluid and in cell cultures of free coelomocytes which are effectors of earthworm immunodefense mechanisms. Antigen is cleaved either intracellularly or by proteolytic enzymes released by coelomocytes into the medium.

The interaction of Staphylococcal protein A with free coelomocytes of annelids.

The Staphylococcal protein A (SpA) binding protein was detected on the surface of annelid coelomocytes. The flow cytometric analysis revealed that 50% coelomocytes of Lumbricus terrestris react with SpA, a figure six times higher than the number of positive coelomocytes found in Eisenia foetida.

Role of saccharides in immunoglobulin--Fc receptor interactions.

The rosettes formed by mouse peritoneal macrophages or DCH-5 cells and TNP-erythrocytes coated with anti-TNP antibodies of different isotypes were inhibited to various extent by monosaccharides. The most effective inhibitors were N-acetylglucosamine, glucosamine, mannose and N-acetylneuraminic acid in 1-5 mmol/L concentrations. Even more efficient were glycopeptides isolated from IgG molecules.

Detection of antigen in the coelomocytes of the earthworm, Eisenia foetida (Annelida).

Earthworms, Eisenia foetida, are able to respond to antigenic stimulation by the formation of the antigen-binding molecules by coelomocytes--the effector cells of annelids' defence reactions. The ability to react with gold-labelled antigen was detected in agranular coelomocytes by electron microscopy. Furthermore, flow cytometry analysis used for quantitative evaluation of antigen binding showed significant increase of both antigen-binding cells and the amount of antigen bound per cell after stimulation.

The interaction of a protein from the coelomic fluid of earthworms with staphylococcal protein A.

A Staphylococcal protein A (SpA)-binding protein was isolated from coelomic fluids of the annelids, Lumbricus terrestris (LT) and Eisenia foetida (EF), by affinity chromatography on SpA-Sepharose. Analyses by polyacrylamide gel electrophoresis in sodium dodecyl sulfate (SDS-PAGE) under reducing and nonreducing conditions showed that SpA-binding activity is associated with a single chain protein, with a mol wt of 62 kD. The carbohydrate moiety of this protein consists of 21.

Characterization of antigen-binding protein in earthworms Lumbricus terrestris and Eisenia foetida.

Injection of antigen into the annelid worms Lumbricus terrestris (LT) and Eisenia foetida (EF) results in a marked increase of coelomic fluid protein concentration and the formation of a protein which binds the stimulating antigen (3). In this report we show that the increases in total protein concentration after first and second doses of antigen were higher and were achieved earlier in LT than in EF, while the accumulation of antigen-binding protein in coelomic fluid was similar in both species. Antigen-binding protein isolated by affinity chromatography retained its original binding activity.

In vitro antigen-binding properties of coelomocytes of Eisenia foetida (Annelida).

Annelids are capable of cellular and humoral defence reactions against foreign antigens. The main aim of this study was to characterise the antigen-binding properties of coelomocytes of Eisenia foetida by means of quantitative autoradiography and direct measurement of radioactivity. It was found that the antigen-binding capacity was significantly increased after antigen stimulation.

[Comparative study of the T- and B-cell immunity systems in human and animal embryogenesis].

Data are presented on the spleen and thymus structure, time of appearance of the lymphocytes and their heterogeneity in the liver, thymus, spleen, lymph nodes and blood of human foetuses with hemochorial placenta (3 to 34 weeks) and of the minipigs foetuses with epitheliochorial placenta (32 to 95 days). In both foetuses the first T- and B-lymphocytes are found in liver, T-lymphocytes are then found in thymus and later in spleen and lymph nodes whereas B-lymphocytes are found, after liver, in spleen. Kinetics of T- and B-lymphocytes during embryogenesis is described.

Response to parenteral stimulation in earthworms L. terrestris and E. foetida.

Injection of different protein molecules into the coelomic cavity of Eisenia foetida (E.F.) and Lumbricus terrestris (L.

Biochemical characterization of Fc gamma receptors of mouse DCH-5 cell line.

Fc gamma receptors (Fc gamma R) were isolated from the culture medium of a mouse hybrid cell line (DCH-5) known as an over-expressor of Fc gamma R, established from a mouse adherent spleen cell and the thymoma cell BW 5147. Proteins adsorbed to insolubilized IgG were separated on Sephacryl S-200. The main fraction with maximum FcR activity was isolated and characterized as a glycoprotein with an effective molar mass of about 55 kg/mol.

The proteins in Lumbricus terrestris and Eisenia foetida coelomic fluids and on coelomocytes reacting with sheep and goat IgG molecules.

Sheep and goat fast migrating IgG molecules and their F(ab')2 fragments react with L. terrestris and E. foetida coelomic fluid proteins.

Lytic activities in coelomic fluid of Eisenia foetida and Lumbricus terrestris.

Coelomic fluids of the two earthworm species E.foetida (E.F.

Antigenic properties of T cell antigen-specific receptors isolated from the surface of rabbit and mouse spleen and lymph node cells.

The presence of a allotypic determinants was tested in fractions obtained by gel filtration of antigen-specific receptors isolated by immunoadsorption from lymphoid cells of antigen-stimulated a3-3 rabbits. This technique, as well as the inhibition of the reaction of isolated receptors with anti-T cell receptor antisera (anti R) by anti-a3 antibodies failed to demonstrate the presence of a allotypic determinants. The inhibitory effect of antigen-specific receptors isolated from the lymphoid cells of stimulated A/J mice on the cytotoxic effect of anti-Ia antibodies on mouse spleen cells in the presence of rabbit complement was tested.

Influence of proteolysis inhibitors and immunoadsorption technique on the composition of rabbit antigen-specific receptor preparations. Presence of Fc receptors.

Addition of proteolysis inhibitors during the isolation procedure of rabbit arsanylated bovine IgG specific receptors decreased significantly the amount of low-molar-mass proteins in all receptor preparations. Rabbit ARS-BGG-specific receptor preparations isolated by immunoadsorption technique contain molecules which do not react with antigen and antibodies against immunoglobulins and have identical molar mass and chymotryptic peptide composition as those of isolated Fc receptors. It is suggested that during isolation of antigen-specific receptors from the surface of lymphoid cells, Fc receptors react with complexes composed of antigen and Ig+ receptors on the surface of immunoadsorbent and are isolated together with antigen-specific receptors.

Characterization of antigen-specific receptors from pig lymphocytes.

Antigen-specific receptors were isolated from the surface of spleen and lymph node cells of ARS-BGG-stimulated miniature pigs using an immunoadsorption technique. The yields of the receptors can be increased by 20-hr cultivation of the cells protein-free medium prior to the isolation procedure. In this case antigen-specific molecules can be isolated not only from the surface of the cells but also from the culture medium.