Effects of schistosoma mansoni worms and eggs on circulating cholesterol and liver lipids in mice

It has previously been shown that experimental infections of the parasitic trematode Schistosoma mansoni, the adult worms of which reside in the blood stream of the mammalian host, significantly reduced atherogenesis in apolipoprotein E gene knockout (apoE(-/-)) mice. These effects occurred in tandem with a lowering of serum total cholesterol levels in both apoE(-/-) and random-bred laboratory mice and a beneficial increase in the proportion of HDL to LDL cholesterol. To better understand how the parasitic infections induce these effects we have here investigated the involvement of adult worms and their eggs on lipids in the host. Our results indicate that the serum cholesterol-lowering effect is mediated by factors released from S. mansoni eggs, while the presence of adult worms seemed to have had little or no effect. It was also observed that high levels of lipids, particularly triacylglycerols and cholesteryl esters, present in the uninfected livers of both random-bred and apoE(-/-) mice fed a high-fat diet were not present in livers of the schistosome-infected mice. (C) 2009 Elsevier Ireland Ltd. All rights reserved.

Orphan worms and, homeless parasites enhance bilaterian diversity

Microscopic endoparasites belonging to the Phylum Myxozoa provide a striking example of how much there is still to be learned about the diversity of the Metazoa. Recent research on myxozoans has provided new insights into evolution within the Bilateria, revealing unparalleled levels of morphological simplification associated with parasitism, a home for an orphan worm, and a hypothesis of the endosymbiotic origin(s) for extrusible intracellular organelles in myxozoans and cnidarians. In addition, discovery of the source of a devastating disease of salmonid fish has enabled researchers to identify two ancient clades within the Myxozoa, and has exposed new mysteries concerning myxozoan life-cycle evolution and evolutionary diversification. This plethora of new insights exemplifies the fundamental value of studying obscure organisms.

Mercury and methylmercury bioaccumulation by polychaete worms is governed by both feeding ecology and mercury bioavailability in coastal mudflats

Polychaete worms are abundant in many mudflats but their importance to coastal food web Hg biomagnification is not known. We sampled sediments and polychaete worms from mudflats in the Bay of Fundy to investigate the bioaccumulation of mercury (Hg) and methylmercury (MeHg) in the coastal invertebrate food web. Hg concentrations in the sediments were low (<20 μg kg−1). Labile Hg (methanol/KOH sediment extraction) in surface sediments (0–1 cm) was positively correlated with Hg bioaccumulation by surface sediment-ingesting polychaetes but, surprisingly, there was a negative correlation between δ15N (i.e. trophic level) and THg bioaccumulation factors in polychaete worms. Worms feeding on deeper sediments contained the greatest MeHg concentrations (69.6 μg kg−1). Polychaetes are an important vector for Hg biomagnification to the coastal avian food web. This research demonstrates that feeding depth and method of feeding are more important than trophic position or sediment Hg concentrations for predicting Hg bioaccumulation.

Is the OECD acute worm toxicity test environmentally relevant? The effect of mineral form on calculated lead toxicity

In a series of experiments the toxicity of lead to worms in soil was determined following the draft OECD earthworm reproduction toxicity protocol except that lead was added as solid lead nitrate, carbonate and sulphide rather than as lead nitrate solution as would normally be the case. The compounds were added to the test soil to give lead concentrations of 625-12500 pg Pb g-1 of soil. Calculated toxicities of the lead decreased in the order nitrate > carbonate > sulphide, the same order as the decrease in the solubility of the metal compounds used. The 7-day LC50 (lethal concentration when 50% of the population is killed) for the nitrate was 5321 +/- 275 mug Pb g(-1) of soil and this did not change with time. The LC50 values for carbonate and sulphide could not be determined at the concentration ranges used. The only parameter sensitive enough to distinguish the toxicities of the three compounds was cocoon (egg) production. The EC50S for cocoon production (the concentration to produce a 50% reduction in cocoon production) were 993, 8604 and 10 246 mug Pb g(-1) of soil for lead nitrate, carbonate and sulphide, respectively. Standard toxicity tests need to take into account the form in which the contaminant is present in the soil to be of environmental relevance. (C) 2002 Elsevier Science Ltd. All rights reserved.

The influence of time on lead toxicity and bioaccumulation determined by the OECD earthworm toxicity test

Internationally agreed standard protocols for assessing chemical toxicity of contaminants in soil to worms assume that the test soil does not need to equilibrate with the chemical to be tested prior to the addition of the test organisms and that the chemical will exert any toxic effect upon the test organism within 28 days. Three experiments were carried out to investigate these assumptions. The first experiment was a standard toxicity test where lead nitrate was added to a soil in solution to give a range of concentrations. The mortality of the worms and the concentration of lead in the survivors were determined. The LC(50)s for 14 and 28 days were 5311 and 5395 mug(Pb) g(soil)(-1) respectively. The second experiment was a timed lead accumulation study with worms cultivated in soil containing either 3000 or 5000 mug(Pb) g(soil)(-1). The concentration of lead in the worms was determined at various sampling times. Uptake at so' Sol both concentrations was linear with time. Worms in the 5000 mug g(-1) soil accumulated lead at a faster rate (3.16 mug Pb g(tissue)(-1) day(-1)) tiss than those in the 3000 mug g(-1) soil (2.21 mug Pb-tissue g(-1) day(-1)). The third experiment was a timed experiment with worms cultivated in tiss soil containing 7000 mugPb g(soil)(-1). Soil and lead nitrate solution were mixed and stored at 20 degreesC. Worms were added at various times over a 35-day period. The time to death increased from 23 h, when worms were added directly after the lead was added to the soil, to 67 It when worms were added after the soil had equilibrated with the lead for 35 days. In artificially Pb-amended soils the worms accumulate Pb over the duration of their exposure to the Pb. Thus time limited toxicity tests may be terminated before worm body load has reached a toxic level. This could result in under-estimates of the toxicity of Pb to worms. As the equilibration time of artificially amended Pb-bearing soils increases the bioavailability of Pb decreases. Thus addition of worms shortly after addition of Pb to soils may result in the over-estimate of Pb toxicity to worms. The current OECD acute worm toxicity test fails to take these two phenomena into account thereby reducing the environmental relevance of the contaminant toxicities it is used to calculate. (C) 2002 Elsevier Science Ltd. All rights reserved.

Earthworms produce granules of intricately zoned calcite

Earthworms of the family Lumbricidae, which includes many common species, produce and secrete up to millimeter-sized calcite granules, and the intricate fine-scale zoning of their constituent crystals is unique for a biomineral. Granule calcite is produced by crystallization of amorphous calcium carbonate (ACC) that initially precipitates within the earthworm calciferous glands, then forms protogranules by accretion on quartz grain cores. Crystallization of ACC is mediated by migrating fluid films and is largely complete within 24 11 of ACC production and before granules leave the earthworm. Variations in the density of defects formed as a byproduct of trace element incorporation during calcite crystall growth have generated zoning that can be resolved by cathodoluminescence imaging at ultraviolet to blue wavelengths and using the novel technique of scanning electron microscope charge contrast imaging. Mapping of calcite crystal orientations by electron backscatter diffraction reveals an approximate radial fabric to the granules that reflects crystal growth from internal nucleation sites toward their margins. The survival within granules of ACC inclusions for months after they enter soils indicates that they crystallize only within the earthworm and in the presence of fluids containing biochemical catalysts. The earthworm probably promotes crystallization of ACC in order to prevent remobilization of the calcium carbonate by dissolution. Calcite granules vividly illustrate the role of transient precursors in biomineralization, but the underlying question of why earth-worms produce granules in volumes sufficient to have a measurable impact on soil carbon cycling remains to be answered.

Dehydration does not affect the radial pressures produced by the earthworm Aporrectodea caliginosa

As a soil dries, the earthworms in that soil dehydrate and become less active. Moisture stress may weaken an earthworm, lowering the radial pressure that the animal can produce. This possibility was investigated for the earthworm Aporrectodea caliginosa (Savigny). Pressures were compared for saturated earthworms (worms taken from saturated soil) and stressed earthworms (worms that had been partially dehydrated by leaving them in dry soil). A load cell was used to record the forces that earthworms produced as they moved through artificial burrows (holes that had been drilled through blocks of aluminium or Perspex). The radial pressure was calculated using the forces exerted and the dimensions of the artificial burrows. There was a negative correlation between burrow diameter and radial pressure, although radial pressure was independent of the length of the block through which the earthworms had burrowed. The highest radial pressures were produced by the anterior segments of the animal. Partial dehydration caused the earthworms to become quiescent, but did not decrease the radial pressure that the earthworms produced. It is suggested that coelomic fluid is retained in the anterior segments while the rest of the animal dehydrates. Dehydrated earthworms became lethargic, and we suggest that lethargy is due to the loss of coelomic fluid from the posterior segments. Coelomic fluid is known to be lost through dorsal pores. In burrowing species of earthworm such as Aporrectodea caliginosa, these pores are only present on the posterior segments.

Metal bioaccumulation and cellular fractionation in an epigeic earthworm (Lumbricus rubellus): the interactive influences of population exposure histories, site-specific geochemistry and mitochondrial genotype

Subcellular fractionation techniques were used to describe temporal changes (at intervals from T0 to T70 days) in the Pb, Zn and P partitioning profiles of Lumbricus rubellus populations from one calcareous (MDH) and one acidic (MCS) geographically isolated Pb/Zn-mine sites and one reference site (CPF). MDH and MCS individuals were laboratory maintained on their native field soils; CPF worms were exposed to both MDH and MCS soils. Site-specific differences in metal partitioning were found: notably, the putatively metal-adapted populations, MDH and MCS, preferentially partitioned higher proportions of their accumulated tissue metal burdens into insoluble CaPO4-rich organelles compared with naive counterparts, CPF. Thus, it is plausible that efficient metal immobilization is a phenotypic trait characterising metal tolerant ecotypes. Mitochondrial cytochrome oxidase II (COII) genotyping revealed that the populations indigenous to mine and reference soils belong to distinct genetic lineages, differentiated by 13%, with 7 haplotypes within the reference site lineage but fewer (3 and 4, respectively) in the lineage common to the two mine sites. Collectively, these observations raise the possibility that site-related genotype differences could influence the toxico-availability of metals and, thus, represent a potential confounding variable in field-based eco-toxicological assessments.

Origin and evolution of a myxozoan worm

Buddenbrockia pluinatellae is an active, muscular, worm-shaped parasite of freshwater bryozoans. This rare and enigmatic animal has been assigned to the Myxozoa on the basis of 18S ribosomal DNA sequences and the presence of malacosporean spores. Here we report cloning of four homologous protein-coding genes from Buddenbrockia worms, the putatively conspecific sac-shaped parasite originally described as Tetracapsula bryozoides and the related sac-shaped parasite Tetracapsuloides bryosalmonae, the causative agent of proliferative kidney disease in salmonid fish. Analyses are consistent with the hypothesis that Buddenbrockia is indeed a malacosporean myxozoan, but do not provide support for conspecificity with either T. bryozoides or T. bryosalmonae. Implications for the evolution of worm-like body plans in the Myxozoa are discussed.

Investigating familiar interfaces to help older adults learn computer applications more easily

Many older adults wish to gain competence in using a computer, but many application interfaces are perceived as complex and difficult to use, deterring potential users from investing the time to learn them. Hence, this study looks at the potential of ‘familiar’ interface design which builds upon users’ knowledge of real world interactions, and applies existing skills to a new domain. Tools are provided in the form of familiar visual objects, and manipulated like real-world counterparts, rather than with buttons, icons and menus found in classic WIMP interfaces. This paper describes the formative evaluation of computer interactions that are based upon familiar real world tasks, which supports multitouch interaction, involves few buttons and icons, no menus, no right-clicks or double-clicks and no dialogs. Using an example of an email client to test the principles of using “familiarity”, the initial feedback was very encouraging, with 3 of the 4 participants being able to undertake some of the basic email tasks with no prior training and little or no help. The feedback has informed a number of refinements of the design principles, such as providing clearer affordance for visual objects. A full study is currently underway.

Pollination ecology in the 21st century: key questions for future research

To inspire new ideas in research on pollination ecology, we list the most important unanswered questions in the field. This list was drawn up by contacting 170 scientists from different areas of pollination ecology and asking them to contribute their opinion on the greatest knowledge gaps that need to be addressed. Almost 40% of them took part in our email poll and we received more than 650 questions and comments, which we classified into different categories representing various aspects of pollination research. The original questions were merged and synthesised, and a final vote and ranking led to the resultant list. The categories cover plant sexual reproduction, pollen and stigma biology, abiotic pollination, evolution of animal-mediated pollination, interactions of pollinators and floral antagonists, pollinator behaviour, taxonomy, plant-pollinator assemblages, geographical trends in diversity, drivers of pollinator loss, ecosystem services, management of pollination, and conservation issues such as the implementation of pollinator conservation. We focused on questions that were of a broad scope rather than case-specific; thus, addressing some questions may not be feasible within single research projects but constitute a general guide for future directions. With this compilation we hope to raise awareness of pollination-related topics not only among researchers but also among non-specialists including policy makers, funding agencies and the public at large.

Dairy farmers’ attitudes and intentions towards improving dairy cow foot health

Dairy cow foot health is a subject of concern because it is considered to be the most important welfare problem in dairy farming and causes economic losses for the farmer. In order to improve dairy cow foot health it is important to take into account the attitude and intention of dairy farmers. In our study the objective was to gain insight into the attitude and intention of dairy farmers to take action to improve dairy cow foot health and determine drivers and barriers to take action, using the Theory of Planned Behavior. Five hundred Dutch dairy farmers were selected randomly and were invited by email to fill in an online questionnaire. The questionnaire included questions about respondents’ intentions, attitudes, subjective norms and perceived behavioral control and was extended with questions about personal normative beliefs. With information from such a framework, solution strategies for the improvement of dairy cow foot health can be proposed. The results showed that almost 70% of the dairy farmers had an intention to take action to improve dairy cow foot health. Most important drivers seem to be the achievement of better foot health with cost-effective measures. Possible barriers to taking action were labor efficiency and a long interval between taking action and seeing an improvement in dairy cow foot health. The feed advisor and foot trimmer seemed to have most influence on intentions to take action to improve dairy cow foot health. Most farmers seemed to be satisfied with the foot health status at their farm, which probably weakens the intention for foot health improvement, especially compared to other issues which farmers experience as more urgent. Subclinical foot disorders (where cows are not visibly lame) were not valued as important with respect to animal welfare. Furthermore, 25% of the respondents did not believe cows could suffer pain. Animal welfare, especially the provision of good care for the cows, was valued as important but was not related to intention to improve dairy cow foot health. The cost-effectiveness of measures seemed to be more important. Providing more information on the effects of taking intervention measures might stimulate farmers to take action to achieve improvement in dairy cow foot health.

Acceptable use policy and employee computer usage: case of Sri Lankan software development industry

Organizations introduce acceptable use policies to deter employee computer misuse. Despite the controlling, monitoring and other forms of interventions employed, some employees misuse the organizational computers to carry out their personal work such as sending emails, surfing internet, chatting, playing games etc. These activities not only waste productive time of employees but also bring a risk to the organization. A questionnaire was administrated to a random sample of employees selected from large and medium scale software development organizations, which measured the work computer misuse levels and the factors that influence such behavior. The presence of guidelines provided no evidence of significant effect on the level of employee computer misuse. Not having access to Internet /email away from work and organizational settings were identified to be the most significant influences of work computer misuse.

Species 2000 & ITIS Catalogue of Life, 2013 Annual Checklist

This release of the Catalogue of Life contains contributions from 132 databases with information on 1,352,112 species, 114,069 infraspecific taxa and also includes 928,147 synonyms and 408,689 common names covering the following groups: Viruses • Viruses and Subviral agents from ICTV_MSL UPDATED! Bacteria and Archaea from BIOS Chromista • Chromistan fungi from Species Fungorum Protozoa • Major groups from ITIS Regional, • Ciliates from CilCat, • Polycystines from WoRMS Polycystina UPDATED!, • Protozoan fungi from Species Fungorum and Trichomycetes database • Slime moulds from Nomen.eumycetozoa.com Fungi • Various taxa in whole or in part from CABI Bioservices databases (Species Fungorum, Phyllachorales, Rhytismatales, Saccharomycetes and Zygomycetes databases) and from three other databases covering Xylariaceae, Glomeromycota, Trichomycetes, Dothideomycetes • Lichens from LIAS UPDATED! Plantae (Plants) • Mosses from MOST • Liverworts and hornworts from ELPT • Conifers from Conifer Database • Cycads and 6 flowering plant families from IOPI-GPC, and 99 families from WCSP • Plus individual flowering plants families from AnnonBase, Brassicaceae, ChenoBase, Droseraceae Database, EbenaBase, GCC UPDATED!, ILDIS UPDATED!, LecyPages, LHD, MELnet UPDATED!, RJB Geranium, Solanaceae Source, Umbellifers. Animalia (Animals) • Marine groups from URMO, ITIS Global, Hexacorals, ETI WBD (Euphausiacea), WoRMS: WoRMS Asteroidea UPDATED!, WoRMS Bochusacea UPDATED!, WoRMS Brachiopoda UPDATED!, WoRMS Brachypoda UPDATED!, WoRMS Brachyura UPDATED!, WoRMS Bryozoa UPDATED!, WoRMS Cestoda NEW!, WoRMS Chaetognatha UPDATED!, WoRMS Cumacea UPDATED!, WoRMS Echinoidea UPDATED!, WoRMS Gastrotricha NEW!, WoRMS Gnathostomulida NEW!, WoRMS Holothuroidea UPDATED!, WoRMS Hydrozoa UPDATED!, WoRMS Isopoda UPDATED!, WoRMS Leptostraca UPDATED!, WoRMS Monogenea NEW!, WoRMS Mystacocarida UPDATED!, WoRMS Myxozoa NEW!, WoRMS Nemertea UPDATED!, WoRMS Oligochaeta UPDATED!, WoRMS Ophiuroidea UPDATED!, WoRMS Phoronida UPDATED!, WoRMS Placozoa NEW!, WoRMS Polychaeta UPDATED!, WoRMS Polycystina UPDATED!, WoRMS Porifera UPDATED!, WoRMS Priapulida NEW!, WoRMS Proseriata and Kalyptorhynchia UPDATED!, WoRMS Remipedia UPDATED!, WoRMS Scaphopoda UPDATED!, WoRMS Tanaidacea UPDATED!, WoRMS Tantulocarida UPDATED!, WoRMS Thermosbaenacea UPDATED!, WoRMS Trematoda NEW!, WoRMS Xenoturbellida UPDATED! • Rotifers, mayflies, freshwater hairworms, planarians from FADA databases: FADA Rotifera UPDATED!, FADA Ephemeroptera NEW!, FADA Nematomorpha NEW! & FADA Turbellaria NEW! • Entoprocts, water bears from ITIS Global • Spiders, scorpions, ticks & mites from SpidCat via ITIS UPDATED!, SalticidDB , ITIS Global, TicksBase, SpmWeb BdelloideaBase UPDATED! & Mites GSDs: OlogamasidBase, PhytoseiidBase, RhodacaridBase & TenuipalpidBase • Diplopods, centipedes, pauropods and symphylans from SysMyr UPDATED! & ChiloBase • Dragonflies and damselflies from Odonata database • Stoneflies from PlecopteraSF UPDATED! • Cockroaches from BlattodeaSF UPDATED! • Praying mantids from MantodeaSF UPDATED! • Stick and leaf insects from PhasmidaSF UPDATED! • Grasshoppers, locusts, katydids and crickets from OrthopteraSF UPDATED! • Webspinners from EmbiopteraSF UPDATED! • Bark & parasitic lices from PsocodeaSF NEW! • Some groups of true bugs from ScaleNet, FLOW, COOL, Psyllist, AphidSF UPDATED! , MBB, 3i Cicadellinae, 3i Typhlocybinae, MOWD & CoreoideaSF NEW!• Twisted-wing parasites from Strepsiptera Database UPDATED! • Lacewings, antlions, owlflies, fishflies, dobsonflies & snakeflies from LDL Neuropterida • Some beetle groups from the Scarabs UPDATED!, TITAN, WTaxa & ITIS Global • Fleas from Parhost • Flies, mosquitoes, bots, midges and gnats from Systema Dipterorum, CCW & CIPA • Butterflies and moths from LepIndex UPDATED!, GloBIS (GART) UPDATED!, Tineidae NHM, World Gracillariidae • Bees & wasps from ITIS Bees, Taxapad Ichneumonoidea, UCD, ZOBODAT Vespoidea & HymIS Rhopalosomatidae NEW!• Molluscs from WoRMS Mollusca NEW!, FADA Bivalvia NEW!, MolluscaFW NEW! & AFD (Pulmonata) • Fishes from FishBase UPDATED! • Reptiles from TIGR Reptiles • Amphibians, birds and mammals from ITIS Global PLUS additional species of many groups from ITIS Regional, NZIB and CoL China NEW!