Extent of Mycobacterium bovis infection in dairy cattle herds subject to partial culling as determined by an interferon-gamma assay

The interferon-gamma (IFN-γ) assay is employed as a complementary diagnostic test for bovine tuberculosis (BTB) in many countries. To simplify this assay, we established a 96-well plate format using the ESAT-6 and CFP-10 antigens and then employed it to determine the extent of Mycobacterium (M.) bovis infection in dairy herds with a history of BTB outbreaks in a country where only selective culling is practiced. The sensitivity and specificity of this IFN-γ assay were 85.9% and 100%, respectively, based on comparison with the conventional single intradermal tuberculin test (SIDT). The IFN-γ assay was also positive in 30.4% and 36.8% of SIDT-negative animals from herds with recent and remote BTB outbreaks, respectively. Of 14 SIDT-negative, IFN-γ positive cattle, five (35.7%) were culture positive and an additional six were positive based on a polymerase chain reaction-based test for M. bovis. Therefore, the IFN-γ assay has the potential to serve as a specific and sensitive test for M. bovis infection in dairy cattle. Further, the results indicated that a substantial portion of SIDT-negative animals in herds with previous BTB outbreaks were actually infected with M. bovis. Accordingly, the present selective-culling strategy may require modifications to include this more sensitive assay.     

Sequential alterations of glucocorticoid receptors in the hippocampus of STZ-treated type 1 diabetic rats

Type 1 diabetes is a common metabolic disorder accompanied by increased blood glucose levels along with glucocorticoid and cognitive deficits. The disease is also thought to be associated with environmental changes in brain and constantly induces oxidative stress in patients. Therefore, glucocorticoid-mediated negative feedback mechanisms involving the glucocorticoid receptor (GR) binding site are very important to understand the development of this disease. Many researchers have used streptozotocin (STZ)-treated diabetic animals to study changes in GR expression in the brain. However, few scientists have evaluated the hyperglycemic period following STZ exposure. In the present study, we found GR expression in the hippocampus varied based on the period after STZ administration for up to 4 weeks. We performed immunohistochemistry and Western blotting to validate the sequential alterations of GR expression in the hippocampus of STZ-treated type 1 diabetic rats. GR protein expression increased significantly until week 3 but decreased at week 4 following STZ administration. GR expression after 70 mg/kg STZ administration was highest at 3 weeks post-treatment and decreased thereafter. Although STZ-induced increase in GR expression in diabetic animals has been described, our data indicate that researchers should consider the sequential GR expression changes during the hyperglycemic period following STZ exposure.     

An extremely luminous panchromatic outburst from the nucleus of a distant galaxy

Variable x-ray and γ-ray emission is characteristic of the most extreme physical processes in the universe. We present multiwavelength observations of a unique γ-ray-selected transient detected by the Swift satellite, accompanied by bright emission across the electromagnetic spectrum, and whose properties are unlike any previously observed source. We pinpoint the event to the center of a small, star-forming galaxy at redshift z = 0.3534. Its high-energy emission has lasted much longer than any γ-ray burst, whereas its peak luminosity was ～100 times higher than bright active galactic nuclei. The association of the outburst with the center of its host galaxy suggests that this phenomenon has its origin in a rare mechanism involving the massive black hole in the nucleus of that galaxy.     

Pharmacokinetics of carprofen in anaesthetized pigs: a preliminary study

ObjectiveTo investigate the pharmacokinetics of carprofen after a single intravenous (IV) dose and multiple oral doses administered to pigs undergoing electroporation of the pancreas.Study designProspective experimental study.AnimalsA group of eight female pigs weighing 31.74 ± 2.24 kg (mean ± standard deviation).MethodsCarprofen 4 mg kg^?1 was administered IV after placement of a central venous catheter during general anaesthesia with isoflurane. Blood samples were collected 30 seconds before and 5, 10, 20, 30 and 60 minutes and 2, 4, 6, 8, 12 and 24 hours after carprofen administration. Subsequently, the same dose of carprofen was administered orally, daily, for 6 consecutive days and blood collected at 36, 48, 60, 72, 96, 120, 144 and 168 hours after initial carprofen administration. Plasma was analysed using liquid chromatography with mass spectrometry. Standard pharmacokinetic parameters were calculated by compartmental analysis of plasma concentration–time curves. Data are presented as mean ± standard error.ResultsThe initial plasma concentration of IV carprofen was estimated at 54.57 ± 3.92 μg mL^?1 and decreased to 8.26 ± 1.07 μg mL^?1 24 hours later. The plasma elimination curve showed a bi-exponential decline: a rapid distribution phase with a distribution half-life of 0.21 ± 0.03 hours and a slower elimination phase with an elimination half-life of 17.31 ± 3.78 hours. The calculated pharmacokinetic parameters were as follows: the area under the plasma concentration–time curve was 357.3 ± 16.73 μg mL^?1 hour, volume of distribution was 0.28 ± 0.07 L kg^?1 and plasma clearance rate was 0.19 ± 0.009 mL minute^?1 kg^?1. The plasma concentration of carprofen, administered orally from days 2 to 7, varied from 9.03 ± 1.87 to 11.49 ± 2.15 μg mL^?1.Conclusions and clinical relevanceCarprofen can be regarded as a long-acting non-steroidal anti-inflammatory drug in pigs.     

Representation of wild Lactuca spp. (Asteraceae, Lactuceae) in world genebank collections

The spread of the genus Lactuca worldwide includes 16 species in Europe, 51 in Asia, 43 in Africa and 12 in America (mostly North American subcontinent). Natural distributions of Lactuca spp. are compared with the representation of wild Lactuca spp. in world genebank collections as recently summarized in the International Lactuca database (ILDB). A total of 27 wild Lactuca species are reported in world genebank collections in the ILDB, however, due to incorrect taxonomic determination the real number of species is lower. The substantial part (92%) of the collections is represented only by three species (L. serriola, L. saligna, L. virosa) and from a geographic viewpoint they are mostly European in origin. The autochthonous species originating from other continents (Asia, Africa, America), which form c. 83% of known Lactuca spp. richness, are very poorly represented in collections (only c. 3%). The majority of accessions originate from Europe (59%) and Asia (37%), nevertheless the whole area of natural distribution is not well covered. An extremely low number of accessions is available from Africa and America (2% each). Thus, the global biodiversity of Lactuca spp. germplasm is represented very poorly and is biased in genebank collections. For future studies of taxonomy, phytogeography, ecology, phylogenetic relationships, genetic diversity, inter- and intra-population structure, resistance research and practical breeding exploitation of wild Lactuca spp. germplasm, plant material from a wider ecogeographic distribution must be collected and introduced into genebank collections more intensively.     

Selected Nutrients and Iron in Interstitial Waters of the Estuary of Southern Baltic (Gulf of Gdañsk and the Pomeranian Bay) in Relation to Redox Potential

The following parameters were determined in the interstitial waters of the Gulf of Gdańsk and the Pomeranian Bay: nutrients (ammonia and phosphates), sulphates, total iron and iron(II) concentrations. Redox potential (Eh), pH, humidity and organic matter content measured as a loss on ignition were determined in bottom sediments from these regions. Interstitial waters of both regions were found to have reducing character (Eh < 250 mV). Reduction processes were more advanced in the Gulf of Gdańsk, rich in organic matter, as evidenced by lower values of the redox potential, lower Fe(III)/Fe_tot ratio, and incidents of sulphates exhaustion.     

OIL AND GAS INDUSTRIAL CHEMICALS' CYTOTOXICITY STUDIED BY ALLIUM TEST

Allium test has already been used to determine cytotoxicity of waste drilling fluids. In the present work the cytotoxicity of four pure chemicals (Defoamex, Idthin 400, Magco Thin and Slick Pipe) was investigated. Those chemicals are components of drilling fluids, therefore, they are usually constituents of oil and gas industry waste waters. The tested chemicals were prepared in 1:9 dilution and cytotoxic effects on root-tip meristem ofAllium ascalonicum were analysed after 24-, 48- and 72-hour-treatments. All samples showed cytotoxicity which was proved by cytogenetic parameters such as inhibition of mitotic activity and increase of mitotic abnormalities and chromosomal aberrations in comparison with the control. Almost all mitotic abnormalities induced by four chemicals tested were the result of disturbed spindle mechanisms accompanied with stickiness. Slick Pipe revealed the most prominent mitodepressive effect and induced a high number of abnormalities. It caused a significant decrease of mitotic activity and increase of mitotic abnormalities after all three treatment durations, while chemicals Defoamex and Magco Thin showed a significant decrease of mitotic activity only after 72-hour-treatment. Chemicals Defoamex, Idthin 400 and Magco Thin revealed a significant increase of mitotic abnormalities after 48- and 72-hour-treatments.     

Effects of artificial acidification and liming on biomass and on the activity of digestive enzymes in Enchytraeidae (Oligochaeta): Results of an ongoing study

Summary The effects of simulated acid rain and acidification combined with liming on enzymatic activities in the gut of the enchytraied Fridericia sp. were studied under laboratory conditions. Simulated mild (pH 4.4) and strong (pH 3.1) acid rain was applied throughout a 52-day experiment. Liming, at rates of 1500 and 4000 kg CaCO₃ powder ha^-1, was applied once on the 27th day of acid rain. After 52 days, the treatment effects were determined by analysing changes in the fresh body weight of enchytraeids and the activities of amylase (EC 3.2.1.1), xylanase (EC 3.2.1.8), trehalase (EC 3.2.1.28) and C₁-cellulase (EC 3.2.1.91) in the gut. The effects were significant in only a few instances. After acidification, xylanase and trehalase activities decreased. The changes in fresh body biomass were not significant. Amylase and cellulase activities increased slightly, possibly because the acidification had a stimulatory effect on soil amylolytic and cellulolytic microorganisms. After liming, both xylanase activity and the enchytraeid body biomass decreased. This was the only marked evidence of a negative effect on the enchytraeids. The high amylase, trehalase and cellulase activities that were observed might have been caused by intensive digestion of dead acidophilous microflora.     

Phenotypic and Genotypic Diversity of European Chestnut (<Emphasis Type="Italic">Castanea sativa</Emphasis> Mill.) in Slovenia – Opportunity for Genetic Improvement

Phenotypic diversity of 244 chestnut trees was investigated. They originate from the Mediterranean and from two continental regions in Slovenia. In 3 years of analyses, length, diameter, thickness and weight of fruits; length and width of hilum, the pellicle intrusion; shape and colour of fruits; and the embryony were dealt with. The continental trees have smaller fruits than the Mediterranean trees; their fruits show greater variability in shape and the pellicle intrusion is stronger. They also exhibit polyembriony more frequently and they rarely have darker stripes. The sample of 46 trees from all three regions was used for the comparison between the phenotypic and genotypic diversity which had been investigated by RAPD analysis. In both cases, the UPGMA method was used for the classification of the trees into groups. Six pomological clusters were established. The clusters I, II, III and V comprise only the trees from the continental part. The cluster IV comprises nine trees of the marron type from the Mediterranean and one KOZ1 tree with equal pomological characteristics but originating from the continental part. The cluster VI is composed of eight trees from the continental part and one RAV3 tree whose fruits are very small and it originates from the Mediterranean. The Jaccard’s coefficient of similarity is used in order to evaluate genetic relations. On the RAPD dendrogram four clusters of trees are defined. The continental trees are divided into three clusters and exhibit greater genotypic diversity than the Mediterranean trees which form only one cluster. With the RAPD analyses the differentiation of the trees with regard to their pomological traits is determined in 60–90% of the cases. The outcome of the research point to the fact that the Slovene chestnut is a rich source of genetic diversity and is very suitable for further breeding purposes.