Leukoencephalomalacia in two horses induced by oral dosing of fumonisin B₁

Leukoencephalomalacia (LEM) was induced by the oral administration of fumonisin B₁ (FB₁) to 2 horses: a filly received 59,5mg/kg of a 50% preparation of FB₁ administered in 21 doses of 1,25-4mg/kg over 33 days; a colt, 44,3mg/kg of 95% pure FB₁ in 20 doses of 1-4 mg/kg in 29 days. Both animals developed nervous signs such as apathy, changes in temperament, inco-ordination, walking into objects, and one showed paralysis of the lips and tongue. Characteristic lesions of LEM were present in the brains. These trials proved conclusively that FB₁ can induce LEM in horses.The articles have been scanned in colour with a HP Scanjet 5590; 600dpi. Adobe Acrobat XI Pro was used to OCR the text and also for the merging and conversion to the final presentation PDF-format.mn201

Leukoencephalomalacia in a horse induced by fumonisin B₁isolated from Fusarium moniliforme

Each of two horses was dosed by stomach tube with culture material on maize of Fusarium moniliforme MRC 826. One horse developed severe hepatosis and mild oedema of the brain after 6 doses of 2,5 g of culture material/kg body mass/day in 7 days. The second horse, in a similar experiment but at a dosage rate of 1,25 g/kg/day, developed mild hepatosis and moderate oedema of the brain. In both animals the brain oedema was particularly noticeable in the medulla oblongata. The mycotoxin fumonisin B₁was extracted and purified from the culture material of F. moniliforme MRC, 826 which contained approximately 1 g/kg of this compound. A horse was injected intravenously 7 times from Day 0-Day 9 with 0,125 mg of fumonisin B₁/kg body mass/day. Clinical signs of neurotoxicosis, which appeared on Day 8, included nervousness followed by apathy, a wide-based stance, trembling, ataxia, reluctance to move, paresis of the lower lip and tongue, and an inability to eat or drink. Euthanasia was performed on the horse on Day 10 while the animal was in a tetanic convulsion. The principal lesions were severe oedema of the brain and early, bilaterally symmetrical, focal necrosis in the medulla oblongata. This report provides experimental evidence that fumonisin B₁, produced by F. moniliforme, causes equine leukoencephalomalacia.The articles have been scanned in colour with a HP Scanjet 5590; 600dpi. Adobe Acrobat XI Pro was used to OCR the text and also for the merging and conversion to the final presentation PDF-format.lmchunu2014mn201

Strange Stars with a Density-Dependent Bag Parameter

We have studied strange quark stars in the framework of the MIT bag model, allowing the bag parameter B to depend on the density of the medium. We have also studied the effect of Cooper pairing among quarks, on the stellar structure. Comparison of these two effects shows that the former is generally more significant. We studied the resulting equation of state of the quark matter, stellar mass-radius relation, mass-central-density relation, radius-central-density relation, and the variation of the density as a function of the distance from the centre of the star. We found that the density-dependent B allows stars with larger masses and radii, due to stiffening of the equation of state. Interestingly, certain stellar configurations are found to be possible only if B depends on the density. We have also studied the effect of variation of the superconducting gap parameter on our results.Comment: 23 pages, 8 figs; v2: 25 pages, 9 figs, version to be published in Phys. Rev. (D

Photosensitivity in South Africa. II. The experimental production of the ovine hepatogenous photosensitivity disease geeldikkop (Tribulosis ovis) by the simultaneous ingestion of Tribulus terrestris plants and cultures of Pithomyces chartarum containing the mycotoxin sporidesmin

The mycoflora of toxic pastures were surveyed during a number of outbreaks of ovine hepatogenous photosensitivity in South Africa. Pure cultures of several isolates were dosed to sheep, but only those of Pithomyces chartarum and Myrothecium verrucaria proved to be toxic. Photosensitization was induced in sheep by dosing them with cultures of a P. chartarum isolate (GAIO) obtained from Tribulus terrestris plants collected during an outbreak of geeldikkop in the Karoo. Thus for the first time a mechanism whereby T. terrestris plants can contribute to the causation of ovine hepatogenous photosensitivity was demonstrated. When cultures of GA10 equivalent to approximately 0, 75-4,0 mg/kg sporidesmin were dosed at Onderstepoort Veterinary Research Institute to Highveld and Karoo sheep on a diet of lucerne, facial eczema was produced. Dosing the same cultures at levels equivalent to c. 1,0 mg/kg of sporidesmin in the Karoo resulted in lesions characteristic of both facial eczema and geeldikkop. Typical hepatic lesions of geeldikkop could be elicited by dosing GAIO at levels equivalent to c. 0,25- 0,7 mg/kg of sporidesmin to Karoo sheep grazing on predominantly T. terrestris pastures in the Karoo. In the latter experiment geeldikkop was induced in the sheep on T. terrestris pastures, while those receiving identical doses on veld with little T. terrestris developed facial aczema. Geeldikkop, therefore, can be brought about by the ingestion of T. terrestris plants together with toxic cultures of P. chartarum. The plant appears not only to act as a vehicle for ingestion of spores, but also to interact with sporidesmin to induce lesions typical of geeldikkop, whereas sporidesmin alone results in facial eczema. Indications are that it can enhance the ability of sporidesmin to cause photosensitivity or, possibly, vice versa. The histopathological findings of these experiments are described in detail.The articles have been scanned in colour with a HP Scanjet 5590; 300dpi. Adobe Acrobat XI Pro was used to OCR the text and also for the merging and conversion to the final presentation PDF-format

Interference in interacting quantum dots with spin

We study spectral and transport properties of interacting quantum dots with spin. Two particular model systems are investigated: Lateral multilevel and two parallel quantum dots. In both cases different paths through the system can give rise to interference. We demonstrate that this strengthens the multilevel Kondo effect for which a simple two-stage mechanism is proposed. In parallel dots we show under which conditions the peak of an interference-induced orbital Kondo effect can be split.Comment: 8 pages, 8 figure

Two lectures on color superconductivity

The first lecture provides an introduction to the physics of color superconductivity in cold dense quark matter. The main color superconducting phases are briefly described and their properties are listed. The second lecture covers recent developments in studies of color superconducting phases in neutral and beta-equilibrated matter. The properties of gapless color superconducting phases are discussed.Comment: 56 pages, 9 figures. Minor corrections and references added. Lectures delivered at the IARD 2004 conference, Saas Fee, Switzerland, June 12 - 19, 2004, and at the Helmholtz International Summer School and Workshop on Hot points in Astrophysics and Cosmology, JINR, Dubna, Russia, August 2 - 13, 200