A mutant of Ustilago maydis deficient in sterol C-14 demethylation: Characteristics and sensitivity to inhibitors of ergosterol biosynthesis

An ergosterol-deficient mutant of Ustilago maydis was compared to the wild type in regard to morphology, growth rate, lipid content, and sensitivity to ergosterol biosynthetic inhibitors. Morphology of mutant sporidia is abnormal and resembles that of fenarimol-treated wild-type sporidia. Doubling time of mutant sporidia is 6.3 hr compared to 2.5 hr for the wild type. The mutant produces 24-methylenedihydrolanosterol, obtusifoliol, and 14α-methylfecosterol; ergosterol is absent. The sterols of the mutant are the same as those which accumulate in wild-type sporidia treated with the sterol C-14 demethylation inhibitors fenarimol, etaconazole, and miconazole. The level of free fatty acids is higher in the mutant than in wild-type cells. Growth of mutant sporidia is not inhibited by fenarimol, etaconazole, and miconazole, or by the sterol Δ¹⁴-reductase inhibitor azasterol A25822B at low concentrations which inhibit growth of wild-type sporidia. The residual growth rate of wild-type sporidia treated with low concentrations of the sterol C-14 demethylation inhibitors is about the same as that of untreated mutant sporidia. Therefore, the mutant would not be recognized as resistant in a wild-type population. The mutant is deficient in sterol C-14 demethylation and is similar in all properties studied to wild-type sporidia treated with sterol C-14 demethylation inhibitors. These findings support the contention that inhibition of sterol C-14 demethylation in U. maydis is the primary mode of toxicity of fenarimol, etaconazole, and miconazole. A secondary mode of toxicity is evident for miconazole and etaconazole at higher concentrations but is doubtful for fenarimol.     

Effects of dietary n-6 and n-3 fatty acids and vitamin E on the immune response of healthy geriatric dogs

OBJECTIVE: To determine the effect of dietary n-6 to n-3 fatty acid ratios and alpha-tocopheryl acetate concentration on immune functions andT cell subpopulations in healthy dogs. ANIMALS: Thirty-two 7- to 10-year old female Beagles. PROCEDURE: For 17 weeks, dogs were fed food that contained low (1.4:1) or high (40:1) ratios of n-6 to n-3 fatty acids in combination with 3 concentrations of all rac-alpha-tocopheryl acetate (low, 17 mg/kg of food; medium, 101 mg/kg; high, 447 mg/kg). Dogs were inoculated twice with a keyhole limpet hemocyanin suspension at 13 and 15 weeks. RESULTS: After 12 weeks, dogs consuming low concentrations of alpha-tocopheryl acetate had lower percentages of CD8+ T cells, compared with dogs consuming medium or high alpha-tocopheryl acetate concentrations. Also, dogs consuming low alpha-tocopheryl acetate concentrations had higher CD4+ to CD8+ T cell ratios. On day 4 of week 15, the percentage of CD8+ T cells was highest in dogs fed medium concentrations of alpha-tocopheryl acetate, compared with other dogs; however, the CD4+ to CD8+ T cell ratio was higher only in dogs fed low concentrations of alpha-tocopheryl acetate with high concentrations of n-3 fatty acids. Dogs consuming low concentrations of n-3 fatty acids with medium concentrations of alpha-tocopheryl acetate had the largest delayed-type hypersensitivity (DTH) skin test response. CONCLUSIONS AND CLINICAL RELEVANCE: An optimum amount of dietary alpha-tocopheryl acetate concentration, regardless of the dietary n-6 to n-3 fatty acid ratio, stimulates the CD8+ T cell population. Effects of an optimum amount of dietary alpha-tocopheryl acetate concentration on the DTH response are blunted by dietary n-3 fatty acids.     

Distribution of tridemorph and its metabolites in barley plants grown to maturity

The distribution of tridemorph residues in previously treated mature barley plants has been determined using a specific g.l.c. method. Tridemorph residues were found in grain, awns, leaves, rachis and stems, the amount of residue in the grain appearing to be variety-specific.     

Spectrum of M-mode echocardiographic abnormalities in 75 cats with systemic hypertension

A retrospective study was performed in 75 hypertensive cats to determine the spectrum and frequency of M-mode echocardiographic abnormalities. Results indicated that 21.3% of the cats had M-mode measurements within normal reference ranges. For cats with echocardiographic abnormalities, changes were variable. Thirty-nine percent of hypertensive cats had hypertrophy of the interventricular septum in diastole, and 41.3% had hypertrophy of the left ventricular (LV) posterior wall in diastole. One cat in five had a dilated left atrium, while fractional shortening and LV internal dimension in diastole were normal in 82.7% and 86.7% of the cats, respectively. The marked variability of echocardiographic findings in hypertensive cats made echocardiography an unreliable screening test for hypertension.     

CNS injury: the role of the cytokine IL-1

Injury to the central nervous system (CNS) and the resulting neuronal loss contribute significantly to morbidity and mortality in human and domestic animal populations. Most insults induce inflammation and the expression of cytokines. The specific roles of these proteins in neurological damage and repair are not completely understood. However, members of the interleukin-1 (IL-1) family have clear therapeutic potential: the IL-1 agonists, IL-1 alpha and IL-1 beta, are induced by CNS injury, and central injection of IL-1 increases, whilst peripheral or central administration of the IL-1 antagonist, IL-1ra, reduces the extent of the damage by more than 50%. The mechanism of action of these cytokines is the subject of intense research. In this review, we summarise approaches that are being used to investigate neuronal cell death, and the contribution of inflammation and cytokines, in particular the IL-1 family, to neurodegenerative disorders.     

ACVIM small animal consensus statement on safe use of cytotoxic chemotherapeutics in veterinary practice

The purpose of this report is to offer a consensus opinion of ACVIM oncology diplomates and technicians on the safe use of cytotoxic chemotherapeutics in veterinary practice. The focus is on minimizing harm to the personnel exposed to the drugs: veterinary practitioners, veterinary technicians, veterinary staff, and pet owners. The safety of the patient receiving these drugs is also of paramount importance, but is not addressed in this statement. Much of the information presented is based on national recommendations by Occupational Safety and Health Administration, National Institute for Occupational Safety and Health, United States Pharmacopeia, and other published regulations. These directives reflect an abundance of caution to minimize exposure to medical personnel, but large‐scale studies about the consequences of long‐term occupational exposure are not available in veterinary medicine. Challenges in the delivery of optimal treatment safely and economically to veterinary patients in general practice without access to a veterinary oncologist or other specialist, because of costs or proximity, remain.     

Survey of veterinary extension in the United States

OBJECTIVE: To assess veterinary extension in the United States as perceived by veterinary extension personnel. DESIGN: Cross-sectional survey. SAMPLE POPULATION: Extension veterinarians in the United States. PROCEDURE: 2 surveys were designed and mailed to extension veterinarians listed by the USDA and the American Association of Extension Veterinarians. RESULTS: 34 states had > or = 1 extension veterinarian. The majority (> 60%) of extension veterinarians did not commit time to resident education and were not involved in research activities. Paradoxically, 23% of responding extension veterinarians did not report extension work. Programs for food animal producers, horse owners, and companion animal owners were provided by 100, 63, and 37% of states, respectively. Continuing education (CE) programs were provided for food animal veterinarians, equine veterinarians, and companion animal veterinarians by 96, 63, and 52% of states, respectively. Challenges facing veterinary extension included limited recognition of veterinary extension activities by universities, lack of university personnel to support CE programs, and decreased support for companion animal extension programs. CONCLUSIONS AND CLINICAL RELEVANCE: Extension veterinarians need to identify and clearly articulate the mission of veterinary extension, develop more collaborative programs across regions, and continue to serve as catalysts to bring diverse constituents together. Extension veterinarians must distinguish their mission not solely as information transfer, which can be accomplished in a variety of ways outside of extension, but as a coherent and consistent program of education and policy developed on a national level and distributed locally.     

Characterizing seabird bycatch in the eastern Australian tuna and billfish pelagic longline fishery in relation to temporal,spatial and biological influences

• 1. Seabirds killed incidentally in Australia's eastern tuna and billfish (ETBF) longline fishery between September 2001 and June 2006 were examined to evaluate species composition and to relate, where possible, capture events to operational and environmental factors.
• 2. During this period 2.129 million hooks on 2202 shots were observed, and 369 birds were reported killed. The majority (78%) of these were flesh‐footed shearwaters (Puffinus carniepes), 53% of which were male and 44% female. Smaller numbers of medium to large sized albatrosses (Diomedeidae, predominantly female) and other shearwaters (Puffinus spp.) and petrels (Pterodroma spp.) dominated the remainder of the bycatch.
• 3. Of the 369 birds reported taken as bycatch, 280 were available for necropsy, and species identifications performed in situ by observers were assessed. While observer identifications were generally correct for common species, performance was poor for less common ones.
• 4. The geographical location (latitude) of shots, season, time of day at which shots were set, and bait type and life status (dead or alive) influenced the seabird bycatch rate. The majority of captures (87% overall) occurred between 30 and 35°S, with bycatch being lowest in winter, and remaining at similar levels across the other seasons.
• 5. The use of live fish bait was generally associated with increased captures of both seabirds overall, and flesh‐footed shearwaters in particular. Copyright © 2010 John Wiley & Sons, Ltd.

     

Behaviour of Phytophthora cinnamomi rands in different soils and water regimes

The effect of different soils, nutrient states and water regimes on the growth, sporulation and lysis of mycelial inocula of Phytophthora cinnamomi has been examined. It has been observed that the requirements for chlamydospore and sporangium production in soils are relatively non-specific with respect to soil type, pH, percentage organic matter and the presence or absence of an additional food source. In contrast to chlamydospore production, however, production of sporangia in soil depends on a sufficiently low water suction pressure. In some soils a low percentage water content or a water content well below field capacity did not necessarily inhibit sporangium production. The pathogen was a good competitor for pieces of both fresh and rotting Castanea sativa radicles. Trichoderma viride appeared to play a significant role in soil by lysing hyphae of P. cinnamomi and inducing it to produce oospores.     

Exploring economic and legal barriers to commercial aquaponics in the EU through the lens of the UK and policy proposals to address them

Aquaponics is a food production system which connects recirculating aquaculture (fish) to hydroponics (plants) systems. Although aquaponics has the potential to improve soil conditions by reducing erosion and nutrient loss and has been shown to reduce food production related carbon emissions by up to 73%, few commercial aquaponics projects in the EU and UK have been successful. Key barriers to commercial success are insufficient initial investment, an uncertain and complex regulatory environment, and the lack of projects operating on a large scale able to demonstrate profitability. In this paper, we use the UK as a case study to discuss the legal and economic barriers to the success of commercial aquaponics in the EU. We also propose three policies: (1) making aquaponics eligible for the new system of Environmental Land Management grants; (2) making aquaponics eligible for organic certification; and (3) clarifying and streamlining the aquaponics licence application process. The UK’s departure from the EU presents a unique opportunity to review agricultural regulations and subsidies, which in turn could provide evidence that similar reforms are needed in the EU.