Platelets interact with Coxsackieviruses B and have a critical role in the pathogenesis of virus-induced myocarditis.

BACKGROUND: To further understand the role of platelets in the pathogenesis of viral infections we explored platelet interaction with Coxsackieviruses B (CVB) 1 and 3. CVB is a group of viruses that cause the majority of human enterovirus-related viral myocarditis; their receptor (CAR) is expressed on the platelet surface and there is a well-characterized CVB3-induced myocarditis murine model. METHODS: Human platelets were infected with CVB1 and 3 and viruses were detected in pellets and in supernatants. C57BL/6J mice with or without platelet depletion were inoculated with CVB3 and peripheral blood and heart samples collected at different times post-infection. RESULTS: CVB1 and 3 RNA and a capsid protein were detected in infected platelets. Despite the fact that titration assays in Vero cells showed increasing infectivity titers over time, supernatants and pellets from infected platelets showed similar levels, suggesting that platelets were not susceptible to a replicative infectivity cycle. CVB binding was CAR-independent and resulted in P-selectin and phosphatidylserine (PS) exposure. CVB3-infected mice showed a rapid thrombocytopenia that correlated with an increase in platelet PS exposure and platelet-leukocyte aggregates without modification of platelet P-selectin expression or von Willebrand factor levels. Mortality, viremia, heart viral titers and myocarditis were significantly higher in platelet-depleted than normal animals. Type I IFN levels were not changed but IgG levels were lower in infected and platelet-depleted mice. CONCLUSIONS: Our data reveal that platelets play a critical role in host survival and immune response against CVB3 infection.

Characterization of the complete genomes of Camelus dromedarius papillomavirus types 1 and 2.

Camel papillomatosis has been described previously, but the genome of the suspected papillomavirus (PV) has not been identified. An outbreak of papillomatosis occurred in a dromedary farm of 55 animals in Sudan during August 2009. The disease was only present in young animals aged about 3-7 months, of which 44 % (11/25) were affected with lesions, mainly on the lips and lower jaw. This study reports for the first time the complete genomes of Camelus dromedarius papillomavirus types 1 (CdPV1) and 2 (CdPV2), isolated from a cauliflower-like nodule and a round oval raised nodule, respectively. Pairwise comparisons of their L1 nucleotide sequences revealed 69.2 % identity, and phylogenetic analyses suggested that these two PV types are grouped within the genus Deltapapillomavirus. Both viruses were isolated from fibropapillomas, although no putative E5 proteins homologous to that of bovine papillomavirus type 1 were identified. The genetic information will be useful for evolutionary studies of the family Papillomaviridae, as well as for the development of diagnostic methods for surveillance of the disease in dromedaries.

Consumer acceptability of conjugated linoleic acid-enriched milk and cheddar cheese from cows grazing on pasture.

Two experiments were conducted to study the consumer acceptability attributes of conjugated linoleic acid (CLA)-enriched milk and cheese from cows grazing on pasture. In experiment 1, 15 cows were fed either a diet containing 51% alfalfa hay plus corn silage and 49% concentrate [total mixed ration (TMR)], were grazed on pasture, or were grazed on pasture and received 3.2 kg/d of a grain mix. The grain mix contained 75% full-fat extruded soybeans (FFES), 10% corn, 10% beet pulp, and 5% molasses. During the final 3 wk of the 6-wk experiment, milk was evaluated for sensory attributes. In experiment 2, 18 cows were fed similar diets as in experiment 1, except replacing the group of cows grazed on pasture and receiving the grain mix was a group of cows grazed on pasture and receiving 2.5 kg/d per cow of the FFES; Cheddar cheese was manufactured from milk. Average CLA contents (g/100 g of fatty acid methyl esters) were 0.52, 1.63, and 1.69 in milk and 0.47, 1.47, and 1.46 in cheese from cows fed a TMR, grazed on pasture, and grazed on pasture and fed the grain mix, respectively. An open and trained panel evaluated CLA-enriched milk for mouth-feel, color, flavor, and quality and evaluated cheese for color, flavor, texture, and quality. Open and trained panel evaluations of milk and cheese showed no differences among treatments for any of the attributes, except that the trained panel detected a more barny flavor in milk from cows grazing pasture compared with milk from cows fed the TMR only. Results suggest that consumer acceptability attributes of CLA-enriched milk and cheese from cows grazing pasture is similar to those of milk and cheese with low levels of CLA.

Continuous increase of epileptogenic effects following application of proteolytic enzymes (buccal ganglia of Helix pomatia).

Epileptic activity of neurons consists of paroxysmal depolarization shifts (PDS) which can be induced presumably in any nervous system by application of an epileptogenic drug. The spontaneous appearance of epileptic activity, however, is based on a largely unknown process which increases susceptibility to epileptic activity (seizure susceptibility in man). It is presently shown that the treatment of ganglia with proteolytic enzymes (Pronase) decreases the effective concentration of epileptogenic drugs, i.e. increases seizure susceptibility. Since proteolytic enzymes are known to primarily affect glial cells a contribution of glia to seizure susceptibility is discussed.

Application of a modified BCR sequential extraction (three-step) procedure for the determination of extractable trace metal contents in a sewage sludge amended soil reference material (CRM 483), complemented by a three-year stability study of acetic acid and EDTA extractable metal content.

This paper provides additional data on a sewage sludge amended soil certified reference material, CRM 483, which was certified in 1997 for its EDTA and acetic acid extractable contents of some trace metals, following standardised extraction procedures. The additional work aimed to test the long-term stability of the material and the applicability of an improved version of the BCR three-step sequential extraction procedure on the sewage sludge amended soil (CRM 483). The paper demonstrates the CRM 483 long-term stability for EDTA and acetic acid extractable contents of Cd, Cr, Cu, Ni, Pb and Zn and gives the results (obtained in the framework of an interlaboratory study) for the extractable contents of the same elements in the CRM 483, following the BCR three-step sequential extraction scheme. The aqua regia extractable contents following the ISO 11466 Standard are also given. The data are given as indicative (not certified) values.

Column leaching and sorption experiments to assess the mobility of potentially toxic elements in industrially contaminated land.

Made-up ground collected from layers of a trial pit excavated on a former industrial site was treated with artificial rainwater in a series of column leaching and sorption experiments. Metal mobility and the ability of various layers of material obtained from the pit to act as sources or sinks of potentially toxic elements were assessed. Samples from different layers varied in their abilities to raise the pH of rainwater applied at pH 3.5 and 4.3, and this was reflected in the amounts of metals mobilised by the rainwater as it percolated through the soil column. Material from the top two layers of the pit released cadmium, copper, manganese, lead, nickel and zinc to the aqueous phase, but the lower layers, with higher buffering capacity, were able to resist acidification even when the equivalent of 12 months' rainfall (western UK) was applied. Column sorption experiments confirmed the ability of material from layer 4 (48-50 cm) to take up copper, manganese and zinc. Metals were determined in the leachates by flame and electrothermal atomic absorption spectrometry and principle anions by ion chromatography.

Improvement of the BCR three step sequential extraction procedure prior to the certification of new sediment and soil reference materials.

The Standards, Measurements and Testing Programme (formerly BCR) of the European Commission proposed a three-step sequential extraction procedure for sediment analysis, following extensive expert consultations and two interlaboratory studies. This scheme was recently used to certify the extractable trace element contents of a sediment reference material (CRM 601). Although this procedure offers a means to ensure the comparability of data in this field, some difficulties concerning the interlaboratory reproducibility still remain, and a new project is currently being conducted to determine the causes of poor reproducibility in the extraction scheme. The final objective of the project is the certification of new sediment and soil reference materials for their extractable contents of Cd, Cr, Cu, Ni, Pb and Zn. This paper presents the results of a small-scale interlaboratory study, which aimed to test a revised version of the extraction schemes by comparing the original and the modified protocols using the CRM 601 sample. This work offers an improvement to the BCR sequential extraction procedure through intercomparison exercises. This improved procedure will allow the obtaining of CRMs to validate analytical data in the analysis of soils and sediments, and it will also facilitate comparability of data in the European Union.

Extraction of ergosterol from peaty soils and determination by high performance liquid chromatography.

The ergosterol content of soil can be used as an indicator of fungal activity. A method has been developed for the extraction and determination of ergosterol in organic soils, as part of a study to assess the correlation between fungal activity and the sequestration of metal pollutants. The moisture content of the soil affected the extraction process. Four consecutive extractions with methanol removed >95% of the ergosterol that can be obtained from the fresh sample (63% moisture) by exhaustive extraction. By freeze drying the soils prior to extraction (a) up to 35% more ergosterol was extracted after a single extraction, (b) >90% of the recoverable ergosterol was collected in two extractions and (c) the repeatability of the extraction was improved. Storage of soil extracts in the absence of light prevents degradation of ergosterol. A previously reported method for determination of ergosterol by HPLC has been improved by modification of the eluant composition. With 46% methanol/46% acetonitrile/8% dichloromethane, ergosterol was eluted with good resolution approximately 8 min after injection of 20 mul of the extract. The detection limit of the HPLC method was 0.5 mug/ml ergosterol, equivalent to 0.06 mug/g in 25 g fresh soil. Changes in ergosterol contents of peaty soil treated with fungicide, and in samples of the peaty podzol and a humus iron podzol in the vicinity of fungal fruiting bodies, have been determined.

Trace element distribution and mobilization in Scottish soils with particular reference to cobalt, copper and molybdenum.

Total and extractable trace element contents have been determined in about 1000 soil profiles representing the main soil series occurring throughout Scotland. The frequency distributions of a number of trace elements in these soils are described and some relationships between total and extractable contents discussed. The geological nature of the soil parent material, soil texture, organic matter content and environmental contamination are the principal factors controlling soil total contents. Soil drainage class, because of its effect on mineral weathering and soil oxidation-reduction conditions, has a major influence on soil extractable contents, availability to plants and crop uptake. Particular attention is paid to cobalt, copper and molybdenum because of their importance for animal health in Scotland.