Foot-and-mouth disease virus: a first inter-laboratory comparison trial to evaluate virus isolation and RT-PCR detection methods

Five European reference laboratories participated in an exercise to evaluate the sensitivity and specificity of their routinely employed RT-PCR tests and cell cultures for the detection and isolation of foot-and-mouth disease (FMD) virus. Five identical sets of 20 coded samples were prepared from 10 vesicular epithelia, which were derived from submissions from suspect cases of FMD or swine vesicular disease (SVD). Sixteen samples were derived from six FMD virus positive epithelia representing four different serotypes (two each of types O and A and one each of types Asia 1 and SAT 2), two from samples which had been found to be negative by antigen ELISA and virus isolation (VI) in cell culture and two from SVD virus positive epithelia. Some of the FMD virus positive samples were prepared from 10-fold serial dilutions of three of the initial suspensions. Each laboratory tested the samples by one or more of its available RT-PCR procedures and inoculated cell cultures that it routinely uses for FMD diagnosis in attempts to isolate virus, the specificity of which was confirmed by antigen ELISA. The best of the RT-PCR assays used in each laboratory gave comparable results while the sensitivity of cell cultures was variable from high in one laboratory, moderate in two and low in two others. This prototype panel of samples would appear suitable for external quality assurance of these tests but would benefit from the inclusion of more negative samples and an extension in the serial dilution range of one or more of the FMD positive sample titration series.     

The efficacy of oxfendazole administered as a bolus compared with a drench formulation

Summary

In a flock of 40 ewe lambs of the Texel breed the anthelmintic oxfendazole was tested in two different formulations, a 2.265 per cent suspension and a 4 gram bolus containing 151 mg active ingredient. All treatments were based on a dose rate of 5 mg / kg body weight. Faecal examinations and larval differentiations were carried out on the day of treatment and two and seven days later. No differences in efficacy were apparent between the two treated groups.

Oxfendazole in either formulation was 100 per cent effective in removing the major strongylids and trichostrongylids.

A lower activity was seen against Strongyloides papillosus.     

Changes in fatty acids composition during seed growth and physicochemical characteristics of oil extracted from four safflower cultivars

Fatty acid contents at different stages ofmaturity and physicochemical characteristics of oilextracted from mature seeds of four safflowercultivars (S208, S400, S541, and S303) were studied. Results indicated that for all cultivars bothsaturated and unsaturated fatty acid contentsfluctuated with seed growth and development. Palmiticacid content decreased up to day 20 after which itstarted to increase for the S400, S541, and S303cultivars, while for S208 it progressively decreased.Stearic acid fluctuated with seed growth anddevelopment. Oleic acid showed slight changes withseed growth and development, while linoleic aciddecreased with seed growth and development for theS400, S541, and S303 cultivars while for S208 afterday 30, it started to increase significantly. For allcultivars, glyceride contents varied among thecultivars with maximum values of 97.70, 2.80 and0.20 for tri-, di- and monoglycerides, respectively. Physicochemical investigation of mature seed oilsshowed that the color, density, refractive index, free fatty acids, peroxide value, saponificationvalue and unsaponifiable matter were similar for allcultivars while viscosity, iodine value, and acetoneinsoluble matter varied among the cultivars.     

Association analysis reveals effects of wheat glutenin alleles and rye translocations on dough-mixing properties

The glutenin loci of wheat (Triticum aestivum L.) are important determinants of bread-making quality, although the effects of alleles at those loci are incompletely understood. We applied an association analysis method to assess the effects of glutenin alleles and 1RS wheat–rye (Secale cereale L.) translocations on dough-mixing properties in 96 wheat cultivars and advanced lines grown at three Colorado locations while accounting for population structure and relatedness of individuals in the population. The results indicated that (1) in the majority of cases, controlling relatedness of individuals reduced the significance of associations between glutenin loci and Mixograph traits; (2) the Glu-D1 and Glu-B3 loci and 1RS translocations had greater impacts on dough-mixing properties compared to other glutenin loci; (3) Glu-B1w, Glu-D1d, and Glu-B3b were consistently associated with greater (more favorable) Mixograph peak time (MPT) than other alleles at the respective loci, whereas Glu-B1e, Glu-D1a, and Glu-B3c were associated with reduced MPT; (4) the 1BL.1RS translocation was associated with a decrease in Mixograph properties. Our results indicate that taking multiple-level relatedness of individuals into account can improve the results of association analysis for wheat-quality traits.     

Neoamphimedine circumvents metnase-enhanced DNA topoisomerase IIα activity through ATP-competitive inhibition

Type IIα DNA topoisomerase (TopoIIα) is among the most important clinical drug targets for the treatment of cancer. Recently, the DNA repair protein Metnase was shown to enhance TopoIIα activity and increase resistance to TopoIIα poisons. Using in vitro DNA decatenation assays we show that neoamphimedine potently inhibits TopoIIα-dependent DNA decatenation in the presence of Metnase. Cell proliferation assays demonstrate that neoamphimedine can inhibit Metnase-enhanced cell growth with an IC(50) of 0.5 μM. Additionally, we find that the apparent K(m) of TopoIIα for ATP increases linearly with higher concentrations of neoamphimedine, indicating ATP-competitive inhibition, which is substantiated by molecular modeling. These findings support the continued development of neoamphimedine as an anticancer agent, particularly in solid tumors that over-express Metnase.     

Interactions between glyphosate and imazethapyr on four annual weeds

Greenhouse and field experiments were conducted to evaluate the efficacy of various combinations of imazethapyr (0, 23, 46, and 70 g ai/ha) with glyphosate (0, 210, 420, 630, and 840 g ae/ha) on Setaria faberi, Amaranthus rudis, Abutilon theophrasti, and Ipomoea hederacea control. Additivity was the most frequently observed interaction and no synergistic interaction occurred throughout this study. The combination of imazethapyr with glyphosate at 210 g/ha caused an antagonistic response on Setaria faberi. Glyphosate at 420 g/ha with or without imazethapyr provided at least 95% control of Setaria faberi. The interaction between glyphosate and imazethapyr was additive on Amaranthus rudis control. Eight of the twenty-one herbicide combinations were antagonistic on Abutilon theophrasti control. Antagonistic interactions occurred when 46 or 70 g/ha of imazethapyr was added to 420 or 630 g/ha of glyphosate; while no antagonistic interactions were noted when glyphosate rate was 840 g/ha. The interactions on Ipomoea hederacea control were additive when the glyphosate rate was at least 420 g/ha. Glyphosate at 210 g/ha plus imazethapyr at 46 or 70 g/ha caused antagonistic interactions on Ipomoea hederacea control. Weed control tended to be more variable when the glyphosate rate was 210 g/ha and the imazethapyr rate was 46 or 70 g/ha. In general, the addition of imazethapyr to low rates of glyphosate improved control of Amaranthus rudis and Ipomoea hederacea and did not improve control of Setaria faberi and Abutilon theophrasti.     

Examining the impact of shade on above-ground biomass and normalized difference vegetation index of C3 and C4 grass species in North-Western NSW,Australia

Previous investigations have detected a directional trend in the normalized difference vegetation index (NDVI) of pastures around scattered paddock trees and identified shade from the tree as the most likely causal factor. This study uses a field experiment to quantify the effect of varying levels of shade on the above-ground biomass and NDVI of three grass species native to Australia (Microlaena stipoides, C₃, shade tolerant; Austrodanthonia richardsonii, C₃, prefers full sunlight, and Chloris ventricosa, C₄, prefers full sunlight) in different seasons. The study demonstrates that shade had little influence on the above-ground biomass of C₃ species but significantly reduced biomass in the C₄ species. Until early winter, the NDVI of each species was generally significantly higher in all shaded treatments than in the no-shade treatment. This suggests that shaded plants retained a higher proportion of green biomass and/or changed leaf shape, increased leaf area and chlorophyll content. Regardless, although not proven in this experiment, it is likely shade prolonged the retention of green plant material into mid to late winter. Overall, this experiment explains the directional trends in NDVI around scattered trees found in previous work and suggests that shade from scattered trees prolongs green pasture production in a range of native grass species, without loss of C₃ pasture biomass.     

Genetically determined sex-reversal in 46,XY humans

Evidence is presented for the existence of a gene, probably on the X chromosome, which prevents testis differentiation when present in 46,XY human embryos. Affected 46,XY women are not completely normal because of premature ovarian involution, as a result of which they have "streak gonads" similiar to those of 45,X women.