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Using laboratory incubation, the response of seed germination and emergence to variability in temperature and light was examined for spider flower ( Cleome gynandra L.), amaranth ( Amaranthus cruentus L.), non-heading Chinese cabbage ( Brassica rapa L. subsp. chinensis ), nightshade ( Solanum retroflexum Dun.), pumpkin ( Cucurbita maxima Duchesne), tsamma melon ( Citrullus lanatus Thunb.), Jew's mallow ( Corchorus olitorius L.) and cowpea ( Vigna unguiculata (L.) Walp.). Effect of temperature on seed germination and emergence was monitored under continuous darkness and at constant temperatures that ranged from 4 °C to 44 °C with 4 °C increments. The effect of light on seed germination was measured at 25 °C. Temperature affected germination rate and final germination percentage of all species tested in ways that were characteristic for each of the species tested. Generally, optimum germination occurred at temperatures ranging between 29 °C and 32 °C but at higher temperatures for V. unguiculata (36 °C) and C. olitorius (35 °C). The minimum temperature for germination ranged between 8 °C and 15 °C, and the maximum between 36 °C and 44 °C. Optimum temperatures for seedling emergence ranged from 25 °C to 31 °C, the maximum between 32 °C and 40 °C and minimum between 2 °C and 13 °C. Light positively ( p < 0.01) affected onset of germination in A. cruentus , B. rapa subsp. chinensis and C. olitorius , and final germination percentage of B. rapa subsp. chinensis , C. lanatus and S. retroflexum . The results suggested that under South African conditions, seeds of the eight species will typically germinate optimally as temperatures rise during spring before the occurrence of very hot temperatures in summer. Due to their positive response to light, germination of B. rapa subsp. chinensis , C. lanatus and S. retroflexum seeds is expected to be optimal when sown at or close to the soil surface. [ABSTRACT FROM AUTHOR]

Abstract: Culicoides biting midges (Diptera: Ceratopogonidae) are involved in the transmission of a variety of pathogens, the economically most important being the orbiviruses that cause bluetongue and African horse sickness; both of which have been shown to be multi-vector diseases. The identification of all potential vectors will be crucial for the implementation of integrated control measures and disease risk analysis. The primary monitoring tools used for the collection of Culicoides midges are various models of suction light traps. In order to facilitate comparison of data between laboratories the efficiency of five traps (Onderstepoort, Rieb, mini-CDC, Pirbright, BG-sentinel), used at present and in the past in Europe, was compared in the field in South Africa. Comparisons were done either in three replicates of a 4×4 or two replicates of a 5×5 randomized Latin square design. The Onderstepoort trap collected significantly more Culicoides midges than the other traps. Relatively small but statistically significant differences were found in the species composition, parous rates, sex ratios as well as the ratio of Culicoides midges to other insects, as determined by the different traps. It will be important to determine the significance and underlying causes for these differences. [Copyright &y& Elsevier]

T lymphocytes play a critical part in inflammatory skin diseases but are targeted by available therapies that have only partial efficacy, significant side-effects, or both. Because psoriasis, atopic dermatitis, and allergic contact hypersensitivity are associated with T helper type 1 (Th1), T helper type 2 (Th2), or mixed Th1–Th2 cell subsets and cytokine types, respectively, there is a need for a better broad-based inhibitor. The macrolactam ascomycin analog, ABT-281, was found to inhibit potently T cell function across species and to inhibit expression of multiple cytokines in human peripheral blood leukocytes which have been found in human skin disease cells and tissues. These included immunoregulatory Th1 (interleukin-2 and interferon-γ) and Th2 (interleukin-4 and interleukin-5) cytokines. ABT-281 was shown to have potent topical activity (ED50 = 0.6% in acetone/olive oil) in a stringent swine model of allergic contact hypersensitivity, but its potency was markedly reduced compared with ascomycin when administered systemically due to more rapid clearance. Topical application of 3% ABT-281 in acetone/olive oil over 25% of the body surface in swine resulted in undetectable blood levels. Compared with a wide potency range of topical corticosteroids in clinical formulations, 0.3% and 1% ABT-281 ointments profoundly inhibited dinitrochlorobenzene-induced contact hypersensitivity in the pig by 78% and 90%, respectively, whereas super-potent steroids such as clobetasol propionate only inhibited in the 50% range and mild to moderate potency steroids such as fluocinolone acetonide were inactive. The potent topical activity of ABT-281 in swine, its superior efficacy, its rapid systemic clearance following uptake into the bloodstream, and its ability to inhibit cytokine biosynthesis of both Th1 and Th2 cell subsets, suggests that it will have a broad therapeutic value in inflammatory skin diseases, including psoriasis, atopic dermatitis, and... [ABSTRACT FROM AUTHOR]

Abstract: Onderstepoort 220V suction light traps were operated at four sites at the ARC-Onderstepoort Veterinary Institute to collect Culicoides midges (Diptera; Ceratopogonidae) at 0.6, 1.4, 2.2 and 2.8m above ground level. Trap heights at these four sites were alternated in three replicates of a 4×4 randomized Latin square design. Culicoides midges belonging to 20 species were collected in 48 collections made from 15 to 30 September 2008. The two most abundant Culicoides species to be collected were Culicoides imicola Kieffer (94.2–95.85%) and Culicoides magnus Colaço (2.21–2.72%). Most Culicoides midges were collected at a height of 2.8m (44.8% of 147158). Statistically significant differences in light trap results were found in the number of midges collected, species composition, parous rates, sex ratios and insect to Culicoides ratios at the various heights. Light trap height is one of a variety of factors that may influence light trap results and highlighted the problems involved in the reliable comparison of light trap data between collection sites. This study emphasized the need for the standardization of techniques for measuring the variables of vectorial capacity. [Copyright &y& Elsevier]