Echinococcus multilocularis infections in domestic dogs and cats from Germany and other European countries

A cross-sectional survey was conducted to estimate the prevalence of Echinococcus multilocularis and E. granulosus infections in domestic dogs and cats from Germany and other European countries. Faecal samples of 21,588 dogs and 10,650 cats routinely submitted to a private veterinary laboratory between June 2004 and June 2005 were examined using the ZnSO(4)-NaCl flotation method. Taeniid eggs were detected in 54 (0.25%) and 37 (0.34%) of the canine and feline faecal samples, respectively. Taeniid eggs were separated and subjected to a DNA preparation and a modified two-step PCR for the detection of Echinococcus spp. based on mitochondrial 12S rRNA genes. PCR products from Echinococcus-negative but cestode-positive reactions were cloned and sequenced to determine the Taenia species. E. multilocularis DNA was specifically amplified in 43 (0.24%) and 25 (0.23%) of the samples from dogs and cats, respectively. E. granulosus DNA was not detected in any sample, while, E. multilocularis-positive samples were detected in dogs from Germany only, those of cats originated from Germany, Denmark and The Netherlands. The prevalence of E. multilocularis egg-positive canine samples was significantly higher in southern (0.35%) than in northern Germany (0.13%). In contrast, no significant regional difference was observed in cats from Germany. Taeniid eggs from Echinococcus-negative samples and from a few samples with macroscopically detected Taenia sp. proglottids were identified as eggs of T. crassiceps (n=8), T. martis, T. serialis, T. polyacantha, T. taeniaeformis and T. pisiformis in dogs (n=1 of each) and T. taeniaeformis (n=11) in cats. The spectrum of cestodes detected in domestic dogs and cats indicate the consumption of small rodents as infection source. The high proportion of E. multilocularis-positive samples, suggest domestic dogs and cats as a possible source of E. multilocularis infection for humans.     

Functionalization of lyocell fibers with TiO2, SiO2, and GLYMO

In the research self-cleaning coatings based on photocatalytically active nano titanium dioxide (TiO₂) were prepared. When applied directly to cellulose fiber surfaces, TiO₂ coatings form weak bonds with fibers. Therefore 3-glycidooxypropyl-trimethoxysilane was used as a coupling agent. It had been applied on the surface of cellulose fibers before the TiO₂ coating was performed. In this case, the silane is in the interface region, where it can be most effective as an adhesion promoter. Silane coupling agents have unique chemical and physical properties not only to enhance bond strength, but more importantly to prevent de-bonding at the interface during composite aging and use as well. The coupling agent provides a stable bond between two otherwise poorly bonding surfaces. Surface properties of these coatings have been examined, such as surface morphology and surface microstructure. TiO₂ nanoparticles were irreversibly attached to the surface of monodisperse silica (SiO₂) spheres and to the surface of Lyocell fibers coated with an epoxy-containing silane coupling agent. Analysis using scanning electron microscopy showed uniform distribution of nanoparticles in the resulting coatings. Fourier transform infrared spectroscopy revealed changes in the surface microstructure occurring after different modifications. In addition, the influence of photocatalytic activity on the mechanical properties of Lyocell fibers was determined. In addition to that, the results indicated that SiO₂ and the coupling agent provide a protection against high oxidizing power of TiO₂ under exposure to daylight irradiation.     

Performance and water requirement of young olives (Olea europaea L.) in the harsh environment of Kuwait

In the harsh environmental conditions of Kuwait, plants are frequently exposed to high temperatures, low relative humidity and drought. Because water resources available for agriculture are limited, an efficient irrigation strategy is vital for sustainable olive production. In view of these facts, a study to determine the behavior and water requirement of young olive plants under Kuwait's environmental conditions was carried out. The investigation included five cultivars (cvs. Arbequina, Barnea, Coratina, Koroneiki and UC13A6) and three levels of irrigation (50, 75 and 100% of ETc) with brackish water (ECe 5.0 dS m^?1). One-year-old grafted plants were used in this study. With the exception of UC13A6, the cultivars showed good adaptation to the harsh weather conditions in Kuwait and to brackish water irrigation during the first 18 months after the beginning of the irrigation treatments. Indeed, they showed good height and shoot growth, with cultivars Barnea, Arbequina and Coratina showing the highest values. Cultivar Barnea was the most vigorous variety under Kuwait's environmental conditions. Vegetative growth in these varieties was not significantly reduced in the 50% ETc treatment. This indicates huge opportunities to improve the water-use-efficiency through further investigations aimed at optimizing the amount of water supplied with irrigation.     

Structure-properties relationship of poly(ethylene terephthalate) wool-type fibres

Two PET wool-type fibres were studied for this research, i.e. a normal wool-type and a low-pilling modification. The structural morphology and crystalline orientation of the fibres were investigated by means of wide-angle x-ray scattering (WAXS), density measurements and infrared (IR) spectroscopy. The degree of crystallinity, crystallite orientation, apparent crystallite dimensions and micro-void system were determined by x-ray scattering. Birefringence measurements were used to study the average molecular orientation and the orientation of macromolecular chain segments in the amorphous regions. In addition, PET samples were conventionally dyed and the effect of the structure on colour was followed using colorimetry. Significant differences between the two PET wool fibre types were observed; i.e. crystallinity is higher for the standard PET wool fibre type, the crystallites are slightly larger and better oriented, long periods are larger, the orientation of molecular segments in non-crystalline phase is higher, and bigger voids are formed. The observed structure gives rise to fibres higher tenacity and higher bending stiffness.     

Detection of Vibrio parahaemolyticus in Mediterranean mussels (Mytilus galloprovincialis) in Slovenia

The aim of this study was to determine the prevalence of Vibrio parahaemolyticus in shellfish samples harvested along the Slovenian coast. Shellfish samples of Mediterranean mussels (Mytilus galloprovincialis) were collected along the Slovenian coast at four locations (Se?a, Piran, Strunjan and Debeli Rti?) between 2006 and 2008. Samples were examined and analysed for the presence of V. parahaemolyticus by conventional and molecular methods. The presence of Vibrio in the samples was examined by conventional methods on plate grown bacterial cells before and after enrichment in alkaline saline peptone water (ASPW). PCR methods were used for the detection of V. parahaemolyticus-specific toxR and tlh genes and of the virulence-associated tdh and trh genes. Out of 168 samples examined, 24 were positive for toxR and tlh genes by PCR from enrichment broth. Five out of 62 (8.1%), 4 out of 32 (12.5%) and 15 out of 74 (20.2%) samples were positive in 2006, 2007 and 2008, respectively. Colonies of V. parahaemolyticus were isolated from only one sample positive for V. parahaemolyticus by PCR.     

Toxoplasma gondii sexual cross in a single naturally infected feline host: Generation of highly mouse-virulent and avirulent clones, genotypically different from clonal types I, II and III

ABSTRACT: Tachyzoite clones obtained from a single Toxoplasma gondii oocyst field sample were genotyped and characterized regarding mouse virulence. PCR-RFLP genotyping of tachyzoites initially isolated from interferon-γ-knockout (GKO) mice, BALB/c mice and VERO cell culture using the nine independent, unlinked genetic markers nSAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1 and Apico revealed mixed T. gondii infections showing combinations of type II and type III alleles at different loci. Forty-five individual clones were obtained from all mixed T. gondii tachyzoite cell cultures by limiting dilution. Sixteen T. gondii clones showed type III alleles at all loci and 29 clones displayed a combination of type II and type III alleles at different loci. Five clone groups were identified in total, four of which include T. gondii clones that showed a non-canonical allele pattern and have never been described in natural infections before. All tested clones, except two, were highly virulent in BALB/c mice. The isolation of different non-canonical T. gondii clones originating from an oocyst sample of a single naturally infected cat demonstrate that sexual recombination as well as re-assortment of chromosomes via a sexual cross of T. gondii occur under natural conditions and result in the emergence of clones with increased virulence in mice.     

Comparison of different commercial DNA extraction kits to detect Toxoplasma gondii oocysts in cat faeces

The cat is the definitive host of Toxoplasma gondii and plays an important role in the transmission of this and other coccidian parasites, e.g. Hammondia hammondi, a protozoon closely related and morphologically similar to T. gondii. A number of techniques to detect T. gondii nucleic acids in feline faeces are described and several extraction kits for isolating pathogen DNA from faeces or soil are commercially available. To compare the performance of such kits with regard to isolating oocyst DNA, a feline sample that had tested negative for coccidian parasites including T. gondii and H. hammondi was spiked with 10(4), 10(3), 10(2), 50 and 10 H. hammondi oocysts. Several ready-to-use stool or soil kits and an in-house method were then used to extract parasite DNA from these spiked faecal samples. Of six kits tested, two were found suitable for the detection of H. hammondi oocysts DNA by the polymerase chain reaction (PCR) in faecal samples with a detection limit of 250 oocysts per 1 g of faecal sample. These two kits revealed a similar, even slightly lower detection limit (50 oocysts per 1 g of sample) when tested with faecal samples spiked with T gondii oocysts.     

Study of the antimony species distribution in industrially contaminated soils

Purpose

The purpose of the present study was to investigate the distribution of antimony (Sb) and its species in soil fractions in order to understand better the real risk associated with Sb in the environment.

Materials and methods

Nine surface soil samples contaminated from lead/zinc and iron smelting operations and coal fired power plants were examined using: (1) four-step sequential extraction procedure (BCR); (2) two-step sequential extraction including ethylenediaminetetraacetic acid (EDTA), sodium hydroxide (NaOH) and NH₄F; and (3) single extraction with EDTA and NaOH. Liquid phase extraction was used for redox speciation of Sb. The distribution of Sb between soil fulvic and humic acids was determined after their chemical separation. The concentrations of Sb were measured by electrothermal atomic absorption spectrometry.

Results and discussion

The main part of total Sb (2.5–105 mg?kg^?1) was associated with the residual fraction in all soils. The exchangeable/carbonate-bound concentrations were 0.83–4.7 % of total Sb. Up to 6.8 % was in the reducible and up to 1.4 % was in the oxidizable fraction. EDTA removed 7.2–11.4 % of total content. Sb(V) was the predominant form in acetic acid and EDTA extracts. Single extraction with 0.1 mol?l^?1 NaOH released up to 13.7 % of soil antimony. The main part of Sb was complexed to the higher molecular weight fraction of soil-derived humic substances.

Conclusions

For highly contaminated soils, 4 % solubility in acetic acid could represent risk of contamination of ground water under specific conditions. Also, the relatively high phytoavailable Sb (7–11 %) can represent a significant proportion in highly polluted soils. Pentavalent antimony was the main antimony species extracted from soils. The main part of the organically antimony was found to be present as complexes with higher molecular weight humic acids fraction.