Chemical characterization and anti-inflammatory effect of rauvolfian, a pectic polysaccharide of Rauvolfia callus.

The pectic polysaccharide named rauvolfian RS was obtained from the dried callus of Rauvolfia serpentina L. by extraction with 0.7% aqueous ammonium oxalate.

Quartz crystal microbalance immunosensor for the detection of antibodies to double-stranded DNA.

We report the development of a novel quartz crystal microbalance immunosensor with the simultaneous measurement of resonance frequency and motional resistance for the detection of antibodies to double-stranded DNA (dsDNA). The immobilization of poly(L-lysine) and subsequent complexation with DNA resulted in formation of a sensitive dsDNA-containing nanofilm on the surface of a gold electrode. Atomic force microscopy has been applied for the characterization of a poly(L-lysine)-DNA film.

Mechanism of action of DNA-hydrolyzing antibodies to DNA from blood of patients with systemic lupus erythematosus.

Four fractions of IgG antibodies to native DNA (nDNA) were obtained from blood of patients with systemic lupus erythematosus (SLE). These antibodies displayed a thermostable DNA-hydrolyzing activity and were different in affinity for DNA-cellulose and sorption on DEAE-cellulose. DNA-hydrolyzing antibodies to nDNA are metal-dependent endonucleases, cause mainly single-strand breaks in DNA, and are active over a wide range of pH.

Special features of the DNA-hydrolyzing activity of the antibodies in systemic lupus erythematosus.

Two types of IgG anti-DNA antibodies exhibiting DNA-hydrolyzing activity have been isolated from blood serum of patients with systemic lupus erythematosus. This DNase activity of antibodies differs from serum DNases by the non-processive mode, temperature resistance, pH optimum, and the rate of DNA hydrolysis. It is suggested that the anti-DNA antibody molecule possessing DNase activity contains two sites: one site determines specificity of antibody-DNA interaction, whereas the other is responsible for manifestation of the catalytic activity.

[Electron immunohistochemical analysis of localization of neutral Mn2+-dependent DNAase. III. Visualization of DNAse binding to isolated chromatin].

Neutral Mn(2+)-dependent DNAse is localized on isolated chromatin structures in both normal and regenerating rat liver. The enzyme was revealed located along the whole length of nucleosomal chain and in hypernucleosomal structures. However, as concerns the quantity of the enzyme, it was distributed unevently along the chromatin, thus reflecting the pattern of different functional states of native chromatin.

[Electron immunohistochemical analysis of localization of neutral Mn2+-dependent DNAase. II. Analysis of ultrastructural localization in epon sections of different organs of the rat].

The use of a conjugate of colloidal gold with monotypic antibodies against a neutral Mn(2+)-dependent DNAse has revealed the enzyme localization in ultrathin Epon sections of glutaraldehyde fixed tissues. Technical procedures involved in fixation, embedding, and immune reactions are described. DNAse has been established in the nuclei in both normal and regenerating liver.

[Electron immunohistochemical analysis of localization of neutral Mn2+-dependent DNAase. I. Synthesis of ferritin and colloidal gold conjugates with monospecific antibodies against neutral Mn2+-dependent DNAase].

Rabbit antibodies against a neutral Mn(2+)-dependent rat liver DNAse were obtained, whose specificity towards DNAse was ascertained by suppression of the enzyme activity both in vitro system and immunoblotting assays. Procedures of synthesis of ferritin and colloidal gold conjugates with antibodies are described. The biological activity of the conjugates proved to be similar to that of the original antibodies.

[Sporicidal effect of Presept and Chloramine B on Bacillus cereus spores].

The sporicidal effect of Presept was compared with Chloramine B on the spores of Bacillus cereus. Either compound was calibrated to the same concentration of active chlorine. While a portion of spore population after 4 hrs of treatment by Chloramine germinated and started to divide in a rich nutrient medium, the optical density of the culture inoculated with spores treated by Presept did not increase even after 7 hrs when exposed to the nutrient medium.

[The interaction of the Ca2(+)- and Mg2(+)-dependent DNAses of sea urchin embryos with DNA].

The interaction between Ca2+- and Mg2+-dependent DNAse from Strongylocentrotus intermedius embryos with native DNA was studied by an immunological electron microscopy method. Colloidal gold-labelling was ascertained to be an endonuclease that reacted along the whole length of the native DNA chain. After the phosphodiester bond hydrolysis the DNA-DNAse complex did not dissociate.

Heat shock applied early in sporulation affects heat resistance of Bacillus megaterium spores.

Cells of Bacillus megaterium 27 were challenged by a 30-min heat shock at 45 degrees C during various sporulation stages and then shifted back to a temperature permissive for sporulation (27 degrees C), at which they developed spores. Heat shock applied at 120 min after the end of the exponential phase induced synthesis of heat shock proteins (HSPs) in the sporangia and delayed the inactivation of spores at 85 degrees C. Several HSPs, mainly HSP 70, could be detected in the cytoplasm of these spores.

[Purification and immunochemical characteristics of neutral Mn-dependent DNAase of chromatin].

A scheme for purification of neutral Mn-dependent chromatin DNAase has been developed. The two-step purification procedure, which includes chromatography on hydroxyapatite and isoelectrofocusing, allows one to obtain preparative amounts of the enzyme having a specific activity of more than 3000 u./mg, molecular mass of 41 kDa and pI of 9.

External factors involved in the regulation of synthesis of an extracellular proteinase in Bacillus megaterium: effect of temperature.

We studied the effect of temperature on the production of an extracellular neutral metalloproteinase of Bacillus megaterium in a laboratory fermentor under constant aeration and pH. The optimal temperature for growth (35-38° C) was higher than that for the synthesis of proteinase during exponential growth (below 31° C). The critical biomass concentration at which the exponential growth terminated decreased with increase in cultivation temperature.

[Relation between DNA replication and neutral Mn 2+-dependent DNAse activity in chromatin].

In cultures of primary murine fibroblasts the 10% serum stimulates the replicative synthesis of DNA inhibited by aphidicolin and araC (cytosine arabinoside). Using direct immunofluorescence analysis, it was shown that antibodies penetrate inside the cells and after 4 hours are pooled in the nuclei, where they remain for another 20 hours. The substitution of antibodies against chromatin DNAase by bovine serum albumin of normal serum gamma-globulins does not interfere with the DNA synthesis induction.

[The determination of the nature of the interaction of neutral Mn2+-dependent DNAse with DNA by immunoelectron microscopy].

The interaction of neutral DNAase with native and denatured DNA was shown by immunoelectron microscopy method with the help of colloidal gold. The neutral DNAase of the rat liver nuclear chromatin is absorbed both to denatured DNA, in which the denatured regions are arranged at 5'-3' ends, and to DNA in which these regions are distributed along the whole molecule.

[Stimulation of DNA synthesis in isolated nuclei of rat liver cells by neutral Mn-dependent DNase of chromatin].

It was demonstrated that neutral Mn-dependent DNAase from rat liver chromatin stimulates the incorporation of labeled precursors of DNA into high molecular weight fractions of isolated nuclear DNA. The effects of DNA-polymerase inhibitors and the properties of DNA synthesis products suggest that neutral Mn-dependent DNAase can induce replicative synthesis of DNA in the nuclei of normal and regenerating rat liver.

[Localization of neutral Mn-dependent DNAse in rat hepatocytes. An immunofluorescent study].

Rabbit antibodies against the Mn-dependent DNAse were obtained. The specificity of the anti-DNAse antibody was established by the enzyme inhibition in vitro. The enzyme activity was inhibited by more than 75 and 54% using rabbit antisera and affinity-purified IgG.

[Ultrastructural localization of neutral DNAse in hepatocytes by immune electron microscopy using colloidal gold].

A method for obtaining of the colloidal gold with particles 20 nm in diameter is described. The use of conjugate of colloidal gold-specific antibodies to the neutral DNAase is shown to determine the DNAase localization on ultrathin epontic sections of rat liver fixed by glutaraldehyde. The conditions of fixation, filling and immune reactions are described.

Inhibitory effect of 1-methyldodecyldimethylamine oxide and N,N-bis(dodecyldimethyl)-1,2-ethanediammonium dibromide on the spores of Bacillus cereus.

1-Methyldodecyldimethylamine oxide (MDDO) and N,N'-bis(dodecyldimethyl)-1,2-ethanediammonium dibromide (BDED) exhibit a significant affinity for the surface of Bacillus cereus spores and adsorb very rapidly to the cells; they have a pronounced inhibitory effect on spore outgrowth. In order to alter the affinity of the spore surface for these inhibitors, the spores were pretreated with sodium dodecyl sulfate (SDS), and with an electronegative (Tween 80) and electropositive (histone) compound. In SDS-pretreated spores the inhibitory effect of MDDO and BDED was abolished to a considerable extent.

[Changes in the RNA content of the blood plasma in rats with Ehrlich ascitic cancer].

The RNA content in the blood plasma of tumour-bearing animals correlates with the tumour growth stage. The development of Ehrlich carcinoma in rats is followed by the RNA increase in the blood plasma, while spontaneous regression of the tumour is accompanied by a decrease of the RNA content in the blood plasma of rats with Ehrlich carcinoma almost to the normal level. The fractional spectrum of the blood plasma RNA in the tumour bearing rats is similar to that of the cell-free ascitic fluid of rats.