Preliminary observations on the population development of anystid and free-living mesostigmatic mites in a cereal field in Southern England

The effect of manipulating cereal aphid population development, by either adding aphids or spraying with an aphid-specific insecticide, on the predatory mite fauna was investigated. Populations of the anystid mite, Anystis baccarum (L.) were very small until late June when numbers built up rapidly at the time of the aphid population decline. There was however, no significant relationship between aphids and numbers of mites over the whole season. Preliminary electrophoretic analysis of two enzymes in the gut of anystid mites indicated that they may have been feeding on thrips, Limothrips cerealium Haliday. The free-living soil Mesostigmata had two population peaks, each related, the first positively and the second negatively to aphid populations.     

Hidden diversity in high-latitude Southern Hemisphere environments: Reinstatement of the genus Rama and description of Vandenhoekia gen. nov. (Cladophoraceae,Ulvophyceae, Chlorophyta), two highly variable genera

The continental coasts and remote islands in the high-latitude Southern Hemisphere, including the subantarctic region, are characterized by many endemic species, high abundance of taxa, and intermediate levels of biodiversity. The macroalgal flora of these locations has received relatively little attention. Filamentous green algae are prolific in the intertidal of southern islands, but the taxonomy, distribution, and evolutionary history of these taxa are yet to be fully explored, mostly due to the difficulty of access to some of these locations. In this study, we examined specimens of the order Cladophorales from various locations in the high-latitude Southern Hemisphere including the subantarctic (the Auckland Islands, Bounty Islands, Campbell Island, Macquarie Island, and Kerguelen Islands), as well as mainland New Zealand, the Chatham Islands, Chile, and Tasmania. The analyses of the rDNA sequences of the samples revealed the existence of two new clades in a phylogeny of the Cladophoraceae. One of these clades is described as the novel genus Vandenhoekia gen. nov., which contains three species that are branched or unbranched. The amended genus Rama is reinstated to accommodate the other clade, and contains four species, including the Northern Hemisphere “Cladophora rupestris.” In Rama both branched and unbranched morphologies are found. It is remarkable that gross morphology is not a predictor for generic affiliations in these algae. This study illustrates that much can still be learned about diversity in the Cladophorales and highlights the importance of new collections, especially in novel locations.     

Formation of recombinants between snowshoe hare and La Crosse bunyaviruses.

Wild-type recombinants were obtained at high frequency from coinfections of BHK cells involving temperature-sensitive, conditional-lethal mutants of snowshoe hare (SSH) and La Crosse (LAC) bunyaviruses. Analyses of two of the recombinants indicated that they have the genome compositions SSH/LAC/SSH and SSH/LAC/LAC for their respective L, M, and S virion RNA species. This evidence, together with that for the genetic stability of the recombinants, indicates that they were derived by segment reassortment of the competent genome pieces of the parental viruses. The SSH/LAC/SSH recombinant appears, from polypeptide analysis, to have the SSH type of nucleocapsid protein (N), whereas the SSH/LAC/LAC recombinant has the LAC nucleocapsid protein, suggesting that the viral S RNA codes for the N protein.     

Aspects of amino acid requirements for in vitro evagination of imaginal leg discs inDrosophila melanogaster

Summary A method of staging late third instar larvae on the basis of salivary gland morphology is described. Using this technique, we investigated stage related amino acid requirements forDrosophila leg disc evagination in vitro. It was found that the requirement for glutamine lasted longer than that of proline. The staging technique should help in the detailed exploration of the late 3rd instar time period in order to bridge the gap between biochemistry and morphogenesis in the initiation of disc evagination.     

MICROSPOROGENESIS IN PEANUT (ARACHIS HYPOGAEA)

The stage of pollen development at the time of anther culture is an important factor in the production of haploids. The objectives of the current study were to develop a staining procedure for peanut (Arachis hypogaea L., ssp. hypogaea) microspores, to describe and document the stages of microsporogenesis in peanut, and to confirm a previous report concerning correlations of peanut floral bud shape with stage of microspore development. A staining procedure using propionic carmine provided adequate staining of pollen mother cells, microspores, and pollen. Pollen mother cells and microspores could easily be differentiated by their size and cell wall structure. Plants grown in a controlled environment were found to have highly synchronized microspore development, both within an anther and among anthers contained in the same bud. In addition, floral bud shape was confirmed as a reliable indicator of anther stage in peanuts.     

16Beta-hydroxylation of dehydroepiandrosterone sulphate by homogenates of human foetal liver.

The chemical syntheses of the 3-sulphates of 16 alpha-acetoxy-, 16 alpha-hydroxy- and 16 beta-hydroxy-dehydroepiandrosterone as their triethylammonium salts are described preparatory to studies of the metabolism of [7 alpha-3 H]dehydroepiandrosterone sulphate by homogenates of human foetal liver. Five main radioactive products of the incubation were separated by partition chromatography on a Celite column. Two were identified as 16 alpha-and 16 beta-hydroxydehydroepiandrosterone 3-sulphates by crystallization to constant specific radioactivity before and after solvolysis. The yields of the conversion to the two epimers were 24.4% (16 alpha) and 1.8% (16 beta).     

Selective inhibition of prostaglandin biosynthesis by gold salts and phenylbutazone

Gold salts and phenylbutazone selectively inhibit the synthesis of PGF_2α and PGE₂ respectively. Lowered production of one prostaglandin species is accompanied by an increased production of the other. Selective inhibition by these drugs was observed in the presence of adrenaline, reduced glutathione and copper sulphate under conditions when most anti-inflammatory compounds inhibited PGE₂ and PGF_2α syntheses equally. It is postulated that selective inhibitors may have a different mode of action and beneficial effects may be related to the endogenous ratio of PGE to PGF required for normal function.     

Searching for the sweet spot of amoebic gill disease of farmed Atlantic salmon: the potential role of glycan-lectin interactions in the adhesion of Neoparamoeba perurans

One of the first critical steps in the pathogenesis of amoebic gill disease (AGD) of farmed salmon is the adhesion of the causative amoeba to the host. The current study aimed to investigate the potential involvement of glycan-binding proteins expressed on the extracellular surface of Neoparamoeba perurans in gill tissue recognition and binding. The glycan-binding properties of the surface membrane of N. perurans and the carbohydrate binding profile of Atlantic salmon gill-derived epithelial cells were identified through the use of glycan and lectin microarrays, respectively. The occurrence of specific carbohydrate-mediated binding was then further assessed by in vitro attachment assays using microtitre plates pre-coated with the main glycan candidates. Adhesion assays were also performed in the presence of exogenous saccharides with the aim of blocking glycan-specific binding activity. Comparative analysis of the results from both lectin and glycan arrays showed significant overlap, as some glycans to which binding by the amoeba was seen were reflected as being present on the gill epithelial cells. The two main candidates proposed to be involved in amoeba attachment to the gills are mannobiose and N-acetylgalactosamine (GalNAc). Adhesion of amoebae significantly increased by 33.5 and 23% when cells were added to α1,3-Mannobiose-BSA and GalNAc-BSA coated plates. The observed increased in attachment was significantly reduced when the amoebae were incubated with exogenous glycans, further demonstrating the presence of mannobiose- and GalNAc-binding sites on the surfaces of the cells. We believe this study provides the first evidence for the presence of a highly specific carbohydrate recognition and binding system in N. perurans. These preliminary findings could be of extreme importance given that AGD is an external parasitic infestation and much of the current research on the development of alternative treatment strategies relies on either instant amoeba detachment or blocking parasite attachment.     

Two silicone nontoxic fouling release coatings: Hydrosilation cured PDMS and CaCO3 filled,ethoxysiloxane cured RTV11

Two silicone coatings have been evaluated for barnacle adhesion. One coating is an unfilled hydrosilation cured polydimethylsiloxane (PDMS) network, while the other is a room temperature vulcanized (RTV), filled, ethoxysiloxane cured PDMS elastomer, RTV11^?. The adhesion strength of one species of barnacle, Balanus eburneus, to the hydrosilation coatings is in the range of 0.37–0.60 kg cm^‐2 while the corresponding range for RTV11 is 0.64–0.90 kg cm^‐2. The easier release of B. eburneus from the hydrosilation cured network compared to RTV11 is discussed in relationship to differences in bulk and surface properties. Preliminary results suggest bulk modulus may be the most important parameter in determining barnacle adhesion strength. In light or mechanical property analysis, a re‐evaluation of surface properties and chemical stability is presented.     

Of 11 candidate steroids,corticosterone concentration standardized for mass is the most reliable steroid biomarker of nutritional stress across different feather types

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