Comparative field study evaluating the activity of recombinant factor VIII Fc fusion protein in plasma samples at clinical haemostasis laboratories.

Discrepancies exist for some of the modified coagulation factors when assayed with different one-stage clotting and chromogenic substrate assay reagents. The aim of this study was to evaluate the performance of a recombinant factor VIII Fc fusion protein (rFVIIIFc), currently in clinical development for the treatment of severe haemophilia A, in a variety of one-stage clotting and chromogenic substrate assays in clinical haemostasis laboratories. Haemophilic plasma samples spiked with rFVIIIFc or Advate(®) at 0.05, 0.20 or 0.80 IU mL(-1) were tested by 30 laboratories using their routine procedures and plasma standards. Data were evaluated for intra- and inter-laboratory variation, accuracy and possible rFVIIIFc-specific assay discrepancies. For the one-stage assay, mean recovery was 95% to 100% of expected for both Advate(®) and rFVIIIFc at 0.8 IU mL(-1). Intra-laboratory percent coefficient of variance (CV) ranged from 6.3% to 7.8% for Advate(®), and 6.0% to 10.3% for rFVIIIFc. Inter-laboratory CV ranged from 10% for Advate(®) and 16% for rFVIIIFc at 0.8 IU mL(-1), to over 30% at 0.05 IU mL(-1) for both products. For the chromogenic substrate assay, the average FVIII recovery was 107% ± 5% and 124% ± 8% of label potency across the three concentrations of Advate(®) and rFVIIIFc, respectively. Plasma rFVIIIFc levels can be monitored by either the one-stage or the chromogenic substrate assay routinely performed in clinical laboratories without the need for a product-specific rFVIIIFc laboratory standard. Accuracy by the one-stage assay was comparable to that of Advate(®), while marginally higher results may be observed for rFVIIIFc when using the chromogenic assay.

[Dimensional structure of bacterial communities of the winter plankton Pechora sea and its formation].

For the Pechora sea, according to microbiological shootings during winter seasons 2002-2005, the analysis of conditions forming of an abundance winter bacterial communities a plankton is carried out. For the outlined varieties of waters, regularities of distribution of segregate groups bacterial communities are discussed. The natural modification of microbiologic indicators ona gradient of parametres a physical and chemical complex is shown. In subglacial conditions average number bacterioplankton 234 thousand in cell/ml, cellular volume - 0.58 µm3, at square of 550 mm2/L. A biomass store a stratum of probed harbour area Pechora sea of 0-25 m to 187 x 10(90 G.

[Seasonal trends in transformation of organic matter forms and enzyme activities in aquatic environment in winter in the Russian Arctic seas by the example of Yenisey Estuary].

Time variations in the main hydrochemical indices of water, organic matter forms, and hydrolytic enzyme activities in aquatic environment have been studied in winter in the southeastern Kara Sea (Yenisey Estuary with depths from 29 to 31 m). The abundance of some components of microproducer (pico-, nano-, and microphytoplankton) and bacterial plankton communities has been analyzed. High functional activity of microcommunities has been demonstrated in winter hydrobiological period. The hydrological, hydrochemical, biochemical, and biological indices of aquatic environment considerably varied in time while their stratification remained stable. The total resources of biologically accessible dissolved organic matter was evaluated by splitting the biological oxygen demand curves obtained under standard conditions (at 22 degrees C).

[Bacterioplankton of the Kola Bay, Barents Sea, (micro- and nanoforms) based on 2002-2003 monitoring data].

Hydrochemical and microbiological investigation in the Kola Bay in 2002-2003 demonstrated that the distribution of bacteria is notably influenced by biogeochemical barriers formed by mixing fresh and sea water. Seasonal changes in the appearance of filterable bacteria, considerable quantities of gram-positive bacteria with thick cell walls, dwarf bacteria, spheroplasts, elementary bodies, and cells with abnormal cell walls during the polar night have been revealed. Cultured bacterial colonies were represented by polymorphic cells. The data obtained refine our knowledge about organotrophic activity of bacterioplankton during the polar night.

[Ecological factors of hydrolytic enzyme activities in the Ob-Yenisey estuarine coastal waters in winter and their modelling]. / ékologicheskie faktory formirovaniia i modelirovaniia urovnia gidroliticheskoi i fermentativnoi aktivnosti vodnikh mass na priust'evom vzmor'e Obi i Eniseia v zimnii period.

The ice conditions at the Ob-Yenisey estuarine coastal waters with relatively diffuse ice cover have been described using the data obtained in the Kara Sea survey aboard the nuclear icebreaker Yamal in January 22-March 6, 2003. The data on the capacity and rate of enzymatic degradation of various forms of organic matter and on the associated ecological factors in the region of active sea water/continental water interaction are given. We analyzed spatial distribution of the main types of water bodies as well as the cascade structure formed by some biogeochemical barriers near the Ob-Yenisey flaw polynya. We also analyzed the correlations between the indices of extracellular biochemical activity in water and the main abiotic and biotic factors during the organotrophic phase. The processes determining the level of biochemical activity in winter water and the rates of potential degradation of various organic compounds are considered.