BackgroundWest Nile Virus (WNV) is endemic in Israel and a significant level of antibodies is present in the population due to natural exposure. Anecdotal cases suggested that the presence of anti-WNV antibodies in intravenous immunoglobulin (IVIG) from Israeli donors (IVIG-IL) assisted the recovery of patients with severe WNV infection.MethodsTo enhance the therapeutic efficacy of IVIG-IL against WNV infection, OMRIX Biopharmaceuticals, Israel, have developed a strategy for selection of plasma units from a 10% fraction of Israeli blood donors with anti-WNV antibodies. Positive units were processed into pharmaceutical grade WNV IVIG (WNIG). Following inoculation with WNV, mice received i.p. injections of different doses (0.01–8 mg/mouse) of IVIG-IL or WNIG, according to the specific experimental protocol.ResultsWNIG was about 10 times more potent (per gr of IgG) than was regular IVIG-IL when tested by ELISA and neutralization assays. In a mouse lethal WNV infection model, prophylactic treatment with WNIG was at least 5–10-fold more potent as compared to treatment with IVIG-IL. Treatment with WNIG during active encephalitis, three or four days following WNV infection, had a significant protective effect. WNIG was also very effective in protecting immunosuppressed mice. Indeed, treatment of dexamethasone-immunosuppressed mice with 0.2 or 1.0 mg WNIG 4 h after virus infection, led to 100% survival.ConclusionIVIG produced from selected plasma donated in WNV endemic regions can be used to produce WNV IVIG with superior activity for therapeutic and prophylactic measures.

Here we report that the 600 bp promoter-like region at the left end of a newly isolated and characterized rat L1 DNA element can activate the prokaryotic chloramphenicol acyltransferase gene in a rat cell line. Activation only occurs when the promoter region is oriented to the transferase gene as it is to the L1 protein encoding sequences and is 75% inhibited by methylation of just 5 of the 22 CpGs present in the promoter. The G + C rich promoter contains enough CpGs to qualify it as a CpG island, but in contrast to other CpG islands, genomic L1 promoters are fully methylated in both somatic cell and sperm DNA as judged by restriction enzyme analysis. Partial demethylation of the genomic promoters by treatment with 5-azacytidine failed to produce discrete L1 transcripts. The relationship of methylation to the evolutionary history and fate of the rat L1 promoter is discussed.

The association between nitrogen-fixing bacteria from the genus Azospiriliwm and the grasses Zea mays and Setaria italica was investigated in sterilized Leonard-jar assemblies. Nitrogen-fLxing bacteria isolated from Cynodon dactylon roots in Israel and Azospirilhun brasikns and Cd) were examined. C2H2 reduction activity was detected in systems containing 0.0 to 0.06 but not in those containing 0.16 gram per liter NH4NO3. The organisms tested signiflcantly increased plant dry weight (50-100%), total N content of leaves (50-100%) and C2H4 production (300-1000 nanomoles C2H4 per plant per hour). Highest C2H2 reduction activities were obtained above 30 C and with high ight intensities. Signiffcant increases in S. itaoica dry weight (DW) and nitrogen (N) content were observed in sand (DW -80%, N -150%), sandy loam soil (DW -80%, N = 75%) and loess (DW -37%, N = 25%). The results obtained in this work clearly demonstrate the potential benefit of inoculating grasses with AzospiriUunmThe potential benefit for grasses associated with nitrogen-fixing Azospirillum has received considerable attention (7). So far, few studies have shown clear evidence that, in this association, the bacteria supplied significant amounts of combined N to the plant and thereby increased growth (3). Nitrogen fixation in grasses associated with Azospirillum has been investigated mainly in detached roots or in soil cores containing the roots (7, 11). Under these conditions, C2H2 reduction tests probably have overestimated the actual activity in situ (2, 8). On the other hand, much lower activities have been reported in intact systems (1, 2, 1 1). One of the main problems encountered when working with Azospirillum in growth chambers has been cross-contamination of the controls (1).Here, the association between different strains of Azospirillum with maize and Setaria has been studied under different controlled environmental and soil conditions in sterilized systems (Leonardjar assemblies). MATERIALS AND METHODSAzospirillum brasilense ATCC 29145 (7) Crone's N-free solution supplemented with NH4NO3 (0.0-0.16 g/l) and microelements (6) was used as the nutrient solution. Each assembly was inoculated with I ml bacterial suspension. Autoclaved aliquots of the same suspension were added to the controls. Unless otherwise stated, in all experiments the plants were grown for 5 to 6 weeks in a Phytotron at the Faculty of Agriculture, Rehovot, at 27 C day and 22 C night in long days (16 h) obtained by extending the natural day length with incandescent illumination (6 1sE m-2 s-' at plant level).The systems were closed with a plastic cover and tightly sealed with plasticine, including the area surrounding the stems. C2H2 was added to the enclosed root system to a final concentration of 12% (v/v), and the C2H4 produced was determined after 24 h by gas chromatography with a flame ionization detector (4). Dry weight was determined on plant material dried at 80 C for 72 h in a forced-air oven. Total N was measured by the Kjeldahl method.Nitrogen-fixing ...

The objective of the present study was to compare the mechanical, kinetic, and biochemical properties of fibrin clots produced using EVICEL Fibrin Sealant (Human) and TISSEEL Fibrin Sealant. The stiffness/elasticity and strength of fibrin clots formed with EVICEL and TISSEEL were assessed using applied mechanical force and thromboelastography (TEG). The factor XIII content of the fibrin clots was also evaluated. Mean Young modulus and tensile strength of the fibrin clots produced by EVICEL were significantly higher than those of clots produced by TISSEEL (P < 0.05 for both). The mean time to initial clot formation and mean time to the predefined level of clot formation were numerically shorter for EVICEL compared with TISSEEL. Furthermore, mean maximal amplitude of the clots formed with EVICEL was significantly greater than that for the clots formed with TISSEEL. Mean concentration of factor XIII for the EVICEL fibrinogen samples tested was 9 IU/ml compared with undetectable concentrations of factor XIII for the TISSEEL fibrinogen samples. Fibrin clots formed with EVICEL have a much higher resistance to stretching and tensile strength and are more capable of maintaining their structure against applied force than those formed with TISSEEL. EVICEL also allows more rapid development of fibrin clots than TISSEEL. This superior clot strength and resilience obtained with EVICEL relative to TISSEEL may be due in large part to the presence of factor XIII.

Azospirillum brasilense strain Cd responded chemotactically to amino acids, sugars and organic acids. Chemotactic rings were observed in semisolid agar plates containing oxidizable substrates. Increasing sodium succinate concentration decreased the velocity of ring expansion. Chemotactic activity of Azospirillum was also examined by a newly developed technique using a channelled chamber. Varying the concentrations of aspartic and glutamic acids affected the chemotactic response of the bacteria. In both assays chemotaxis was obtained under conditions that prevented aerotaxis.