Study of electrokinetic potential of drug micro-carriers prepared from resorbable polymers bioplastotan

The study investigates electrokinetic potentials of microparticles prepared from biodegradable poly-3-hydroxybutyrate depending upon the method of preparation employed and taking into account the size of particles maintained in liquid media. The ζ-potential of microparticles prepared from emulsion by solvent evaporation method was ?20 mV; the ζ-potential of microparticles prepared by spray drying was reduced to ?95 mV. The value of ζ-potential was influenced by drug loading into microparticles; the drug-loaded microparticles maintained in balanced phosphate buffer for 30 days had higher physical stability than those without drug loading.     

A simple method of quantitative recovery of nucleotides from thin layers

A simple method for quantitative recovery of uv-absorbing compounds from thin layers is described. The method consists in fixation of the appropriate area of adsorbent with nitrocellulose solution. After drying the fixed spots get detached from the glass as solid platelets. Therefore it becomes easy to perform subsequent quantitative procedures like elution, radioactivity counting, etc.     

Development of enzyme-linked immunosorbent assay for detection of Mycoplasma pneumoniae antigens

The variant of enzyme-linked immunosorbent assay (ELISA) for detection of Mycoplasma pneumoniae (Mp) antigens in sera of patients with respiratory infections was developed. Sensitivity of detection of soluble antigens of Mp in modeling experiment varied from 1.5 to 1.0 ng/ml (on protein). Approbation of the assay was performed using 50 serum samples obtained from patients with confirmed diagnosis of respiratory mycoplasmosis. In the ELISA test Mp antigens were detected in 96% of samples. Obtained results were confirmed by testing of these serum samples and isolated from them circulating immune complexes (CICs) in immunoblotting using polyclonal antibodies labeled by horse-radish peroxidase. Mp antigenswere detected both in free state and as components of CICs. Specific reaction was observed with proteins, which molecular mass varied from 30 to 170 kDa (30, 37, 45, 56, 58, 72, 90, 130 and 170 (160) kDa). Obtained results point to appropriateness of use of developed assay for detection Mp antigens in sera of patients with respiratory infections.     

Genetic and phenotypic differences between thistle populations in response to habitat and weed management practices

Rapid evolutionary change is increasingly being recognized as commonplace, but the evolutionary consequences for species and ecosystems under human‐induced selection regimes have not been explored in detail, although many species occur in such environments. In a common garden experiment and with amplified fragment length polymorphism markers, we examined whether genetic differentiation has taken place between spatially intermixed populations of creeping thistles Cirsium arvense (Asteraceae) collected from a natural habitat (maritime shores), a semi‐natural habitat (road verges) and arable fields under two management regimes: conventional and organic farming. Populations of C. arvense have altered genetically and locally adapted their growth patterns with changed land use. Although plants from different habitats showed similar total biomass production, shoot and root production was higher for maritime populations, suggesting selection for increased competitive ability. Competitive ability then declined in the order semi‐natural, conventional farms and organic farms. Thistles in arable fields may be more selected for tolerance against disturbances from herbicides and mechanical weed control. In addition, early shoot sprouting and genetic analysis showed differentiation between plants originating from conventional farms and farms that were converted to organic 9–30 years ago, suggesting some adaptation to altered crop cultivation practices. © 2010 The Linnean Society of London, Biological Journal of the Linnean Society, 2010, 99 , 797–807.     

Parasites of stone loach Barbatula barbatula (L., 1758) (Balitoridae) in small rivers of the upper and Middle Volga Basin

Infection by parasites has been studied in 189 specimens of Barbatula barbatula (Linnaeus, 1758) from eight rivers in Yaroslavl province over 4 years. A total of 41 parasite species are identified in stone loach. The following parasite taxa have been found: parasitic Protozoa (Kinetoplastidea (2), Myxozoa (6), and Ciliophora (7)) and parasitic Metazoa (Monogenea (5), Cestoda (4), Trematoda (9), Nematoda (4), Acanthocephala (3), and Bivalvia (1)). Stone loach is recorded for the first time as a new host for seven parasite species: Chloromyxum truttae Lèger, 1906, Gyrodactylus cobitis Bychowsky, 1933, Paracaryophylaeus gotoi (Motomura, 1927), Neogryporhynchus cheilancristrotus (Wedl, 1955), Paracoenogonimus ovatus Katsurada, 1914, Camallanus truncates (Rudolphi, 1814), and Neoechinorhynchus crassus Van Cleave, 1919. The most abundant parasites are Raphidascaris acus (Bloch, 1779) (28.6–100%, 1–64), Crepidostomum oschmarini Zhokhov et Pugacheva, 1998 (18.2–71.4%, 1–40), Paracoenogonimus ovatus (3.13–71.4% 1–34), and Gyrodactylus nemachili Bychowsky, 1936 (3.85–100%, 1–65).     

Acceptor activity of hypermethylated E. coli tRNAMetf

The acceptor activity of normal E. coli tRNA(Met) (f) was compared with that of a preparation with surplus methyl groups introduced by a crude methylase preparation from rat hepatoma. No changes in charging were detected when the aminoacylation was carried out in a homologous system. The data indicate that neither the surplus methyl groups by themselves, nor the eventual changes in spatial arrangement are essential for charging of E. coli tRNA(Met) (f).