Lipid imbalance in individuals predisposed to rheumatoid arthritis: possible relationship with common infections.

Lipid balance was studied in female patients with late rheumatoid arthritis, their healthy female relatives liable to autoimmune diseases, and healthy women without family history of autoimmune diseases. Previous studies showed that the relatives of patients with rheumatoid arthritis suffered from frequent stubborn common infections, which prompted us to analyze the relationship between lipid metabolism and the infectious syndrome parameters. Blood serum and cells were collected for analysis when females had no clinical symptoms of infections (in all groups) or laboratory signs of inflammatory process (in the relatives and controls). Proatherogenic shifts in serum lipid composition presumably associated with frequent lasting infections were detected in individuals liable to rheumatoid arthritis development. Elevated cholesterol content in mononuclear leukocytes in this group could lead, in turn, to dysfunctions of these cells and augment the defects of anti-infection defense. The parameters of lipid balance in patients with late rheumatoid arthritis were close to the age-specific norm.

[Changing extracellular matrix of cells during development of suspension culture of Triticum timopheevii Zhuk].

A study was made of the contents of the main polysaccharide fractions in the cell wall, and extracellular polysaccharides, and of the activity of cell wall enzymes during cultivation of suspension culture of cells of the winter wheat Triticum timopheevii Zhuk. It was shown that within 3 days of cultivation (a phase enriched in dividing cells), on the background of increased callose contents in plant cells, amounts of pectins and hemicelluloses extracted by 4N alkali decreased. The content of polysaccharides reached its initial level by the end of culturing. A parallel analysis of glycosidase activity in cell walls has shown their considerable activation at the stage enriched by dividing cells, which decreased at a transition of culture into the stationary level. The increased activity of hydrolyzing enzymes was combined with an increased efflux of extracellular polysaccharides into culture medium. The detected changes in polysaccharide composition of the cell wall at the first phase indicate its qualitative changes during cell wall reconstruction at the beginning of cytokines, whereas extensive expansion of cell wall was seen on the phase of elongation.

Absorption and digestion of phagocytized objects by mononuclear phagocytes during rheumatoid arthritis.

Radioisotope study of mononuclear phagocytes from patients with rheumatoid arthritis showed impaired ingestion of bacteria in the presence of pronounced digestive activity. Excessive accumulation methylumbelliferyl phosphate beta-glucuronide (product of hydrolysis catalyzed by glucuronidase released from cells) into the incubation medium was observed. This was probably related to the predominance of extracellular digestion.

[Effect of oligosaccharides on adaptation of winter wheat seedlings to negative temperature]. / Uchastie oligosakharidov v adaptatsii prorostkov ozimoi pshenitsy k otritsatel'noi temperature.

We studied the dynamics of endogenous content of bioactive oligosaccharides in the roots of winter wheat seedlings. Previously these oligosaccharides proved to mediate development of frost resistance during the first days of hardening (Zabotina et al., 1998). The changes in their endogenous content can be described by a single-humped curve peaking 6 h after the onset of frost hardening. The capacity of these polysaccharides to increase frost resistance (LT50 was evaluated by leakage of electrolytes) when added to growth medium did not depend on the pretreatment duration (from 1.5 to 18 h) but decreased if they were introduced in the course of the adaptive response. Inhibition of the adaptive response by inhibitors of RNA and protein synthesis was ceased in the presence of the oligosaccharides. We believe that the oligosaccharides that are products of metabolism of the cell wall polysaccharides are involved in adaptation to low temperature.

Biologically active oligosaccharides from pectins of Pisum sativum L. seedlings affecting root generation.

Two physiologically active oligosaccharide fractions were isolated from pectin of Pisum sativum L. cell wall after its partial acid hydrolysis. These fractions displayed stimulating and inhibiting effects on root formation in thin-layer explants. The subsequent separation of these fractions by gel permeation and anion-exchange chromatography resulted in fractions with effective concentrations two orders of magnitude lower than the concentrations of the initial fractions. The resulting oligosaccharides displayed their effect on the earliest stage of the rhizogenesis associated with formation of root primordias. The rhizogenesis-inhibiting fraction suppressed cell division by 30-50%. The stimulating fraction mainly contained fragments of xyloglucan and galactan, and the inhibiting fraction contained fragments of xyloglucan, galactan, and arabinan. The polymerization degrees of the stimulating and of the inhibiting oligosaccharides were 10-11 and 5-6, respectively.

[Role of monovalent cations in protein-lipid interaction in chloroplast membranes]. / Rol' donovalentnykh kationov v belok-lipidnykh vzaimodeistviiakh membran khloroplastov.

Role of monovalent cations in chloroplast membranes was investigated using chlorophyll a as an endogenous fluorescent probe. It is found using specific membrane modification by trypsin and lipophylic polypeptide, gramicidin S, that cations cause changes in the chlorophyll microenvironment. The mechanism of these changes is suggested to be an induction of the protein conformational ability, which results in the rearrangement of their lipid environment and in the differentiation of the latter.