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Sample records for arthropod antiviral response

  1. Antiviral responses of arthropod vectors: an update on recent advances.

    Science.gov (United States)

    Rückert, Claudia; Bell-Sakyi, Lesley; Fazakerley, John K; Fragkoudis, Rennos

    2014-01-01

    Arthropod vectors, such as mosquitoes, ticks, biting midges and sand flies, transmit many viruses that can cause outbreaks of disease in humans and animals around the world. Arthropod vector species are invading new areas due to globalisation and environmental changes, and contact between exotic animal species, humans and arthropod vectors is increasing, bringing with it the regular emergence of new arboviruses. For future strategies to control arbovirus transmission, it is important to improve our understanding of virus-vector interactions. In the last decade knowledge of arthropod antiviral immunity has increased rapidly. RNAi has been proposed as the most important antiviral response in mosquitoes and it is likely to be the most important antiviral response in all arthropods. However, other newly-discovered antiviral strategies such as melanisation and the link between RNAi and the JAK/STAT pathway via the cytokine Vago have been characterised in the last few years. This review aims to summarise the most important and most recent advances made in arthropod antiviral immunity. PMID:25674592

  2. Antiviral responses of arthropod vectors: an update on recent advances.

    Science.gov (United States)

    Rückert, Claudia; Bell-Sakyi, Lesley; Fazakerley, John K; Fragkoudis, Rennos

    2014-01-01

    Arthropod vectors, such as mosquitoes, ticks, biting midges and sand flies, transmit many viruses that can cause outbreaks of disease in humans and animals around the world. Arthropod vector species are invading new areas due to globalisation and environmental changes, and contact between exotic animal species, humans and arthropod vectors is increasing, bringing with it the regular emergence of new arboviruses. For future strategies to control arbovirus transmission, it is important to improve our understanding of virus-vector interactions. In the last decade knowledge of arthropod antiviral immunity has increased rapidly. RNAi has been proposed as the most important antiviral response in mosquitoes and it is likely to be the most important antiviral response in all arthropods. However, other newly-discovered antiviral strategies such as melanisation and the link between RNAi and the JAK/STAT pathway via the cytokine Vago have been characterised in the last few years. This review aims to summarise the most important and most recent advances made in arthropod antiviral immunity.

  3. A novel system for the launch of alphavirus RNA synthesis reveals a role for the Imd pathway in arthropod antiviral response.

    Directory of Open Access Journals (Sweden)

    Vasanthi Avadhanula

    2009-09-01

    Full Text Available Alphaviruses are RNA viruses transmitted between vertebrate hosts by arthropod vectors, primarily mosquitoes. How arthropods counteract alphaviruses or viruses per se is not very well understood. Drosophila melanogaster is a powerful model system for studying innate immunity against bacterial and fungal infections. In this study we report the use of a novel system to analyze replication of Sindbis virus (type species of the alphavirus genus RNA following expression of a Sindbis virus replicon RNA from the fly genome. We demonstrate deficits in the immune deficiency (Imd pathway enhance viral replication while mutations in the Toll pathway fail to affect replication. Similar results were observed with intrathoracic injections of whole virus and confirmed in cultured mosquito cells. These findings show that the Imd pathway mediates an antiviral response to Sindbis virus replication. To our knowledge, this is the first demonstration of an antiviral role for the Imd pathway in insects.

  4. Arthropod-borne flaviviruses and RNA interference : seeking new approaches for antiviral therapy

    NARCIS (Netherlands)

    Diosa-Toro, Mayra; Urcuqui-Inchima, Silvio; Smit, Jolanda M

    2013-01-01

    Flaviviruses are the most prevalent arthropod-borne viruses worldwide, and nearly half of the 70 Flavivirus members identified are human pathogens. Despite the huge clinical impact of flaviviruses, there is no specific human antiviral therapy available to treat infection with any of the flaviviruses

  5. Responses of prairie arthropod communities to fire and fertilizer: Balancing plant and arthropod conservation

    Science.gov (United States)

    Hartley, M.K.; Rogers, W.E.; Siemann, E.; Grace, J.

    2007-01-01

    Fire is an important tool for limiting woody plant invasions into prairies, but using fire management to maintain grassland plant communities may inadvertently reduce arthropod diversity. To test this, we established twenty-four 100 m2 plots in a tallgrass prairie in Galveston County, Texas, in spring 2000. Plots were assigned a fire (no burn, one time burn [2000], two time burn [2000, 2001]) and fertilization treatment (none, NPK addition) in a full factorial design. Fertilization treatments allowed us to examine the effects of fire at a different level of productivity. We measured plant cover by species and sampled arthropods with sweep nets during the 2001 growing season. Path analysis indicated that fertilization reduced while annual fires increased arthropod diversity via increases and decreases in woody plant abundance, respectively. There was no direct effect of fire on arthropod diversity or abundance. Diptera and Homoptera exhibited particularly strong positive responses to fires. Lepidoptera had a negative response to nutrient enrichment. Overall, the negative effects of fire on the arthropod community were minor in contrast to the strong positive indirect effects of small-scale burning on arthropod diversity if conservation of particular taxa is not a priority. The same fire regime that minimized woody plant invasion also maximized arthropod diversity.

  6. Arthropod responses to the experimental isolation of Amazonian forest fragments

    Directory of Open Access Journals (Sweden)

    Heraldo L. Vasconcelos

    2012-12-01

    Full Text Available Arthropods are the most diverse and abundant group of animals found in tropical lowland forests, and in light of ongoing global change phenomena, it is essential to better understand their responses to anthropogenic disturbances. Here we present a review of arthropod responses to forest deforestation and fragmentation based on studies conducted at the Biological Dynamics of Forest Fragments Project (BDFFP, located in central Amazonia. These studies involved a wide range of arthropod groups. All but one of the studies evaluated changes in total species number or species density in relation to fragment size, (i.e. area effects, and one-third also evaluated edge effects. Our review indicates that almost every arthropod group studied showed some kind of response to reduction in forest area, including altered abundances, species richness or composition in comparisons of different-sized fragments, fragmented and non-fragmented areas, or comparisons of forest edges and forest interiors. These responses tended to be idiosyncratic, with some groups showing predicted declines in abundance or diversity in the fragments while others show no response or even increases. However, some of the observed effects on arthropods, or on the ecological processes in which they are involved, were transient. The most likely explanation for this was the rapid development of secondary growth around fragments, which greatly increased the connectivity between fragments and the remaining forest. Although the BDFFP has provided many insights regarding the effects of forest fragmentation on arthropod assemblages, many diverse groups, such as canopy arthropods, have received scant attention. For those that have been studied, much remains to be learned regarding the long-term dynamics of these assemblages and how landscape context influences local biodiversity. The BDFFP remains an exceptional site in which to investigate how the ecological interactions in which arthropods are

  7. Induction and suppression of tick cell antiviral RNAi responses by tick-borne flaviviruses

    NARCIS (Netherlands)

    Schnettler, E.; Tykalova, H.; Watson, M.; Sharma, M.; Sterken, M.G.; Obbard, D.J.; Lewis, S.H.; McFarlane, M.; Bell-Sakyi, L.; Barry, G.; Weisheit, S.; Best, S.M.; Kuhn, R.J.; Pijlman, G.P.; Chase-Topping, M.E.; Gould, E.A.; Grubhoffer, L.; Fazakerley, J.K.; Kohl, A.

    2014-01-01

    Arboviruses are transmitted by distantly related arthropod vectors such as mosquitoes (class Insecta) and ticks (class Arachnida). RNA interference (RNAi) is the major antiviral mechanism in arthropods against arboviruses. Unlike in mosquitoes, tick antiviral RNAi is not understood, although this in

  8. The antiviral response to gamma interferon.

    Science.gov (United States)

    Costa-Pereira, Ana P; Williams, Timothy M; Strobl, Birgit; Watling, Diane; Briscoe, James; Kerr, Ian M

    2002-09-01

    A role for alpha/beta interferon (IFN-alpha/beta) in the IFN-gamma antiviral response has long been suggested. Accordingly, possible roles for autocrine or double-stranded-RNA (dsRNA)-induced IFN-alpha/beta in the IFN-gamma response were investigated. Use was made of wild-type and a variety of mutant human fibrosarcoma cell lines, including mutant U5A cells, which lack a functional IFN-alpha/beta receptor and hence an IFN-alpha/beta response. IFN-gamma did not induce detectable levels of IFN-alpha/beta in any of the cell lines, nor was the IFN-gamma response per se dependent on autocrine IFN-alpha/beta. On the other hand, a number of responses to dsRNA [poly(I). poly(C)] and encephalomyocarditis virus were greatly enhanced by IFN-gamma pretreatment (priming) of wild-type cells or of mutant cells lacking an IFN-alpha/beta response; these include the primary induction of dsRNA-inducible mRNAs, including IFN-beta mRNA, and, to a lesser extent, the dsRNA-mediated activation of the p38 mitogen-activated protein (MAP) kinase(s). IFN-gamma priming of mRNA induction by dsRNA is dependent on JAK1 and shows biphasic kinetics, with an initial rapid (<30-min) response being followed by a more substantial effect on overnight incubation. The IFN-gamma-primed dsRNA responses appear to be subject to modulation through the p38, phosphatidylinositol 3-kinase, and ERK1/ERK2 MAP kinase pathways. It can be concluded that despite efficient priming of IFN-beta production, the IFN-alpha/beta pathways play no significant role in the primary IFN-gamma antiviral response in these cell-virus systems. The observed IFN-gamma priming of dsRNA responses, on the other hand, will likely play a significant role in combating virus infection in vivo.

  9. Antiviral macrophage responses in flavivirus encephalitis.

    Science.gov (United States)

    Ashhurst, Thomas Myles; Vreden, Caryn van; Munoz-Erazo, Luis; Niewold, Paula; Watabe, Kanami; Terry, Rachael L; Deffrasnes, Celine; Getts, Daniel R; Cole King, Nicholas Jonathan

    2013-11-01

    Mosquito-borne flaviviruses are a major current and emerging threat, affecting millions of people worldwide. Global climate change, combined with increasing proximity of humans to animals and mosquito vectors by expansion into natural habitats, coupled with the increase in international travel, have resulted in significant spread and concomitant increase in the incidence of infection and severe disease. Although neuroinvasive disease has been well described for some viral infections such as Japanese Encephalitis virus (JEV) and West Nile virus (WNV), others such as dengue virus (DENV) have recently displayed an emerging pattern of neuroinvasive disease, distinct from the previously observed, systemically-induced encephalomyelopathy. In this setting, the immune response is a crucial component of host defence, in preventing viral dissemination and invasion of the central nervous system (CNS). However, subversion of the anti-viral activities of macrophages by flaviviruses can facilitate viral replication and spread, enhancing the intensity of immune responses, leading to severe immune-mediated disease which may be further exacerbated during the subsequent infection with some flaviviruses. Furthermore, in the CNS myeloid cells may be responsible for inducing specific inflammatory changes, which can lead to significant pathological damage during encephalitis. The interaction of virus and cells of the myeloid lineage is complex, and this interaction is likely responsible at least in part, for crucial differences between viral clearance and pathology. Recent studies on the role of myeloid cells in innate immunity and viral control, and the mechanisms of evasion and subversion used by flaviviruses are rapidly advancing our understanding of the immunopathological mechanisms involved in flavivirus encephalitis and will lead to the development of therapeutic strategies previously not considered. PMID:24434318

  10. DMPD: An arms race: innate antiviral responses and counteracting viral strategies. [Dynamic Macrophage Pathway CSML Database

    Lifescience Database Archive (English)

    Full Text Available 18031256 An arms race: innate antiviral responses and counteracting viral strategies...arms race: innate antiviral responses and counteracting viral strategies. PubmedID 18031256 Title An arms ra...ce: innate antiviral responses and counteracting viral strategies. Authors Schrod

  11. DMPD: Triggering the innate antiviral response through IRF-3 activation. [Dynamic Macrophage Pathway CSML Database

    Lifescience Database Archive (English)

    Full Text Available 17395583 Triggering the innate antiviral response through IRF-3 activation. Hiscott...g the innate antiviral response through IRF-3 activation. PubmedID 17395583 Title Triggering the innate anti...viral response through IRF-3 activation. Authors Hiscott J. Publication J Biol Ch

  12. Leaf litter arthropod responses to tropical forest restoration.

    Science.gov (United States)

    Cole, Rebecca J; Holl, Karen D; Zahawi, Rakan A; Wickey, Philipp; Townsend, Alan R

    2016-08-01

    Soil and litter arthropods represent a large proportion of tropical biodiversity and perform important ecosystem functions, but little is known about the efficacy of different tropical forest restoration strategies in facilitating their recovery in degraded habitats. We sampled arthropods in four 7- to 8-year-old restoration treatments and in nearby reference forests. Sampling was conducted during the wet and dry seasons using extractions from litter and pitfall samples. Restoration treatments were replicated in 50 × 50-m plots in four former pasture sites in southern Costa Rica: plantation - trees planted throughout the plot; applied nucleation/islands - trees planted in patches of different sizes; and natural regeneration - no tree planting. Arthropod abundance, measures of richness and diversity, and a number of functional groups were greater in the island treatment than in natural regeneration or plantation treatments and, in many cases, were similar to reference forest. Litter and pitfall morphospecies and functional group composition in all three restoration treatments were significantly different than reference sites, but island and plantation treatments showed more recovery than natural regeneration. Abundance and functional group diversity showed a much greater degree of recovery than community composition. Synthesis and applications: The less resource-intensive restoration strategy of planting tree islands was more effective than tree plantations in restoring arthropod abundance, richness, and functional diversity. None of the restoration strategies, however, resulted in similar community composition as reference forest after 8 years of recovery, highlighting the slow rate of recovery of arthropod communities after disturbance, and underscoring the importance of conservation of remnant forests in fragmented landscapes. PMID:27551373

  13. Responsiveness of arthropod herbivores and their natural enemies to modified weed management in corn.

    Science.gov (United States)

    Albajes, Ramon; Lumbierres, Belén; Pons, Xavier

    2009-06-01

    Alteration of weed flora as consequence of the deployment of genetically modified herbicide-tolerant crops may affect higher trophic levels in agrosystems. A 4-yr study is being conducted in Spain to investigate interrelations between weeds and associated arthropods in corn fields. In a first step, the work aimed to detect the most responsive arthropods to weed management changes. To identify the most responsive arthropods, arthropod composition and abundance in herbicide-tolerant corn plots treated twice with glyphosate and untreated plots were compared for 2 yr. Plots were sampled seven times during the season by visual inspection and pitfall and yellow sticky traps to estimate abundance and activity of the main arthropod herbivores, predators, and parasitoids. As intended, the abundance and composition of weed flora was strongly altered by the differential herbicide treatments. Several groups of arthropods responded to the weed changes but in variable directions. Whereas leafhoppers and aphids were more abundant on herbicide-treated plots, the contrary was found for phytophagous thrips. Among predators, Orius sp., spiders, and trombidids were more abundant on treated plots, whereas nabids and carabids were more abundant in untreated plots; the same case was found for carabids and spiders caught in pitfall traps. Among parasitoids, ichneumonids were more abundant in untreated plots and mymarids in treated plots. These results cannot be interpreted in terms of nontarget effects of postemergence treatments with broad-spectrum herbicides; for this, a comparison with conventional weed management practices should be done and this is the current step in the study. PMID:19508806

  14. Equal temperature-size responses of the sexes are widespread within arthropod species

    DEFF Research Database (Denmark)

    Hirst, Andrew G.; Horne, Curtis; Atkinson, David

    2015-01-01

    Sexual size dimorphism (SSD) is often affected by environmental conditions, but the effect of temperature on SSD in ectotherms still requires rigorous investigation. We compared the plastic responses of size-at-maturity to temperature between males and females within 85 diverse arthropod species,...

  15. Evasion of the Interferon-Mediated Antiviral Response by Filoviruses

    Directory of Open Access Journals (Sweden)

    Washington B. Cárdenas

    2010-01-01

    Full Text Available The members of the filoviruses are recognized as some of the most lethal viruses affecting human and non-human primates. The only two genera of the Filoviridae family, Marburg virus (MARV and Ebola virus (EBOV, comprise the main etiologic agents of severe hemorrhagic fever outbreaks in central Africa, with case fatality rates ranging from 25 to 90%. Fatal outcomes have been associated with a late and dysregulated immune response to infection, very likely due to the virus targeting key host immune cells, such as macrophages and dendritic cells (DCs that are necessary to mediate effective innate and adaptive immune responses. Despite major progress in the development of vaccine candidates for filovirus infections, a licensed vaccine or therapy for human use is still not available. During the last ten years, important progress has been made in understanding the molecular mechanisms of filovirus pathogenesis. Several lines of evidence implicate the impairment of the host interferon (IFN antiviral innate immune response by MARV or EBOV as an important determinant of virulence. In vitro and in vivo experimental infections with recombinant Zaire Ebola virus (ZEBOV, the best characterized filovirus, demonstrated that the viral protein VP35 plays a key role in inhibiting the production of IFN-α/β. Further, the action of VP35 is synergized by the inhibition of cellular responses to IFN-α/β by the minor matrix viral protein VP24. The dual action of these viral proteins may contribute to an efficient initial virus replication and dissemination in the host. Noticeably, the analogous function of these viral proteins in MARV has not been reported. Because the IFN response is a major component of the innate immune response to virus infection, this chapter reviews recent findings on the molecular mechanisms of IFN-mediated antiviral evasion by filovirus infection.

  16. Alphavirus Infection: Host Cell Shut-Off and Inhibition of Antiviral Responses

    Directory of Open Access Journals (Sweden)

    Jelke J. Fros

    2016-06-01

    Full Text Available Alphaviruses cause debilitating disease in humans and animals and are transmitted by blood-feeding arthropods, typically mosquitoes. With a traditional focus on two models, Sindbis virus and Semliki Forest virus, alphavirus research has significantly intensified in the last decade partly due to the re-emergence and dramatic expansion of chikungunya virus in Asia, Europe, and the Americas. As a consequence, alphavirus–host interactions are now understood in much more molecular detail, and important novel mechanisms have been elucidated. It has become clear that alphaviruses not only cause a general host shut-off in infected vertebrate cells, but also specifically suppress different host antiviral pathways using their viral nonstructural proteins, nsP2 and nsP3. Here we review the current state of the art of alphavirus host cell shut-off of viral transcription and translation, and describe recent insights in viral subversion of interferon induction and signaling, the unfolded protein response, and stress granule assembly.

  17. Vertical T-maze choice assay for arthropod response to odorants.

    Science.gov (United States)

    Stelinski, Lukasz; Tiwari, Siddharth

    2013-01-01

    Given the economic importance of insects and arachnids as pests of agricultural crops, urban environments or as vectors of plant and human diseases, various technologies are being developed as control tools. A subset of these tools focuses on modifying the behavior of arthropods by attraction or repulsion. Therefore, arthropods are often the focus of behavioral investigations. Various tools have been developed to measure arthropod behavior, including wind tunnels, flight mills, servospheres, and various types of olfactometers. The purpose of these tools is to measure insect or arachnid response to visual or more often olfactory cues. The vertical T-maze olfactometer described here measures choices performed by insects in response to attractants or repellents. It is a high throughput assay device that takes advantage of the positive phototaxis (attraction to light) and negative geotaxis (tendency to walk or fly upward) exhibited by many arthropods. The olfactometer consists of a 30 cm glass tube that is divided in half with a Teflon strip forming a T-maze. Each half serves as an arm of the olfactometer enabling the test subjects to make a choice between two potential odor fields in assays involving attractants. In assays involving repellents, lack of normal response to known attractants can also be measured as a third variable. PMID:23439130

  18. Engineered Mammalian RNAi Can Elicit Antiviral Protection that Negates the Requirement for the Interferon Response

    OpenAIRE

    Asiel Arturo Benitez; Laura Adrienne Spanko; Mehdi Bouhaddou; David Sachs; Benjamin Robert tenOever

    2015-01-01

    While the intrinsic antiviral cell defenses of many kingdoms utilize pathogen-specific small RNAs, the antiviral response of chordates is primarily protein-based and not uniquely tailored to the incoming microbe. In an effort to explain this evolutionary bifurcation, we determined whether antiviral RNA interference (RNAi) was sufficient to replace the protein-based type I interferon (IFN-I) system of mammals. To this end, we recreated an RNAi-like response in mammals and determined its effect...

  19. Induction and suppression of the innate antiviral responses by picornaviruses

    NARCIS (Netherlands)

    Feng, Q.

    2014-01-01

    On the front line of innate antiviral immune reactions is the type I interferon (IFN-α/β) system. IFN-α/β are small signaling molecules that can be produced by virtually all nucleated cells in our body upon virus infections, and induce a so-called “antiviral state” in neighboring cells by activating

  20. Coxsackievirus cloverleaf RNA containing a 5' triphosphate triggers an antiviral response via RIG-I activation

    NARCIS (Netherlands)

    Feng, Qian; Langereis, Martijn A; Olagnier, David; Chiang, Cindy; van de Winkel, Roel; van Essen, Peter; Zoll, Jan; Hiscott, John; van Kuppeveld, Frank J M

    2014-01-01

    Upon viral infections, pattern recognition receptors (PRRs) recognize pathogen-associated molecular patterns (PAMPs) and stimulate an antiviral state associated with the production of type I interferons (IFNs) and inflammatory markers. Type I IFNs play crucial roles in innate antiviral responses by

  1. Unidentified angular recurrent ulceration responsive to antiviral therapy

    Directory of Open Access Journals (Sweden)

    Rahmi Amtha

    2013-03-01

    Full Text Available Background: Recurrent ulcer on angular area is usually called stomatitis angularis. It is caused by many factors such as vertical dimension reduce, vitamin B12, and immune system deficiency, C. albicans and staphylococcus involvement. Clinically is characterized by painful fissure with erythematous base without fever. Purpose: to describe an unidentified angular ulcer proceeded by recurrent ulcers with no response of topical therapy. Case: An 18-years old male came to Oral Medicine clinic in RSCM who complained of angular recurrent ulcers since 3 years ago which developed on skin and bleed easily on mouth opening. Patient had fever before the onset of ulcers. Large, painful, irregular ulcers covered by red crustae on angular area bilaterally. Patient has been treated with various drugs without improvement and lead to mouth opening limitation. Intra oral shows herpetiformtype of ulcer and swollen of gingival. Case management: Provisional diagnosis was established as viral infection thus acyclovir 200 mg five times daily for two weeks and topical anti inflammation gel were administered. Blood test for IgG/IgM of HSV1 and HSV2 were non reactive, however ulceration showed a remarkable improvement. The ulcers healed completely after next 2 weeks with acyclovir. Conclusion: The angular ulceration on above patient failed to fulfill the criteria of stomatitis angularis or herpes labialis lesion. However it showed a good response to antiviral. Therefore, unidentified angular ulceration was appointed, as the lesion might be triggered by other type of human herpes virus or types of virus that response to acyclovir.Latar belakang: ulser rekuren pada sudut mulut biasanya disebut stomatitis angularis. Kelainan ini disebabkan oleh banyak faktor seperti berkurangnya dimensi vertikal, defisiensi vitamin B12 dan sistem kekebalan tubuh, infeksi C. albicans serta staphylococcus. Secara klinis kelainan ini ditandai dengan fisur sakit pada sudut mulut dengan dasar

  2. Replicative Homeostasis III: implications for antiviral therapy and mechanisms of response and non-response

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    Sallie Richard

    2007-03-01

    Full Text Available Abstract While improved drug regimens have greatly enhanced outcomes for patients with chronic viral infection, antiviral therapy is still not ideal due to drug toxicities, treatment costs, primary drug failure and emergent resistance. New antiviral agents, alternative treatment strategies and a better understanding of viral pathobiology, host responses and drug action are desperately needed. Interferon (IFN and ribavirin, are effective drugs used to treat hepatitis C (HCV, but the mechanism(s of their action are uncertain. Error catastrophe (EC, or precipitous loss of replicative fitness caused by genomic mutation, is postulated to mediate ribavirin action, but is a deeply flawed hypothesis lacking empirical confirmation. Paradoxically ribavirin, a proven RNA mutagen, has no impact on HCV viraemia long term, suggesting real viruses, replicating in-vitro, as opposed to mathematical models, replicating in-silico, are likely to resist EC by highly selective replication of fit (~consensus sequence genomes mediated, in part, by replicative homeostasis (RH, an epicyclic mechanism that dynamically links RNApol fidelity and processivity and other viral protein functions. Replicative homeostasis provides a rational explanation for the various responses seen during treatment of HCV, including genotype-specific and viral load-dependent differential response rates, as well as otherwise unexplained phenomena like the transient inhibition and rebound of HCV viraemia seen during ribavirin monotherapy. Replicative homeostasis also suggests a primarily non-immunological mechanism that mediates increased immune responsiveness during treatment with ribavirin (and other nucleos(tide analogues, explicating the enhanced second-phase clearance of HCV ribavirin promotes and, thus, the apparent immunomodulatory action of ribavirin. More importantly, RH suggests specific new antiviral therapeutic strategies.

  3. Vertical T-maze Choice Assay for Arthropod Response to Odorants

    OpenAIRE

    Stelinski, Lukasz; Tiwari, Siddharth

    2013-01-01

    Given the economic importance of insects and arachnids as pests of agricultural crops, urban environments or as vectors of plant and human diseases, various technologies are being developed as control tools. A subset of these tools focuses on modifying the behavior of arthropods by attraction or repulsion. Therefore, arthropods are often the focus of behavioral investigations. Various tools have been developed to measure arthropod behavior, including wind tunnels, flight mills, servospheres, ...

  4. Direct presentation is sufficient for an efficient anti-viral CD8+ T cell response.

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    Ren-Huan Xu

    2010-02-01

    Full Text Available The extent to which direct- and cross-presentation (DP and CP contribute to the priming of CD8(+ T cell (T(CD8+ responses to viruses is unclear mainly because of the difficulty in separating the two processes. Hence, while CP in the absence of DP has been clearly demonstrated, induction of an anti-viral T(CD8+ response that excludes CP has never been purposely shown. Using vaccinia virus (VACV, which has been used as the vaccine to rid the world of smallpox and is proposed as a vector for many other vaccines, we show that DP is the main mechanism for the priming of an anti-viral T(CD8+ response. These findings provide important insights to our understanding of how one of the most effective anti-viral vaccines induces immunity and should contribute to the development of novel vaccines.

  5. Impaired antiviral response of adenovirus-transformed cell lines supports virus replication.

    Science.gov (United States)

    Bachmann, Mandy; Breitwieser, Theresa; Lipps, Christoph; Wirth, Dagmar; Jordan, Ingo; Reichl, Udo; Frensing, Timo

    2016-02-01

    Activation of the innate immune response represents one of the most important cellular mechanisms to limit virus replication and spread in cell culture. Here, we examined the effect of adenoviral gene expression on the antiviral response in adenovirus-transformed cell lines; HEK293, HEK293SF and AGE1.HN. We demonstrate that the expression of the early region protein 1A in these cell lines impairs their ability to activate antiviral genes by the IFN pathway. This property may help in the isolation of newly emerging viruses and the propagation of interferon-sensitive virus strains.

  6. Viral Response to Specifically Targeted Antiviral Therapy for Hepatitis C and the Implications for Treatment Success

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    Curtis L Cooper

    2010-01-01

    Full Text Available Currently, hepatitis C virus (HCV antiviral therapy is characterized by long duration, a multitude of side effects, difficult administration and suboptimal success; clearly, alternatives are needed. Collectively, specifically targeted antiviral therapy for HCV (STAT-C molecules achieve rapid viral suppression and very high rapid virological response rates, and improve sustained virological response rates. The attrition rate of agents within this class has been high due to various toxicities. Regardless, several STAT-C molecules are poised to become the standard of care for HCV treatment in the foreseeable future. Optimism must be tempered with concerns related to the rapid development of drug resistance with resulting HCV rebound. Strategies including induction dosing with interferon and ribavirin, use of combination high-potency STAT-C molecules and an intensive emphasis on adherence to HCV antiviral therapy will be critical to the success of this promising advance in HCV therapy.

  7. Interactions of macrophages with probiotic bacteria lead to increased antiviral response against vesicular stomatitis virus

    DEFF Research Database (Denmark)

    Ivec, Martin; Botic, Tanja; Koren, Srecko;

    2007-01-01

    understanding of their role in the activation of macrophages and their stimulation of proinflammatory cytokine production in early viral infection was the main goal of this study. Our in vitro model study showed that probiotic bacteria, either from the species Lactobacillus or Bifidobacteria have the ability......Macrophages are an important cellular component of the innate immune system and are normally rapidly recruited and/or activated at the site of virus infection. They can participate in the antiviral response by killing infected cells, by producing antiviral cytokines such as nitric oxide...... and by producing chemokines and immunoregulatory cytokines that enable the adaptive immune response to recognize infected cells and perform antiviral effector functions. Probiotics, as a part of the normal gut intestinal flora, are important in supporting a functional yet balanced immune system. Improving our...

  8. Neopterin as a Marker of Response to Antiviral Therapy in Hepatitis C Virus Patients

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    Gregory F. Oxenkrug

    2012-01-01

    Full Text Available Predicting the efficacy of antiviral treatment of hepatitis C virus (HCV is of importance for both patient well-being and health care expense. The expression of interferon-stimulated genes (IFN-SGs in the liver was suggested as a marker of response to anti-viral therapy. IFN-SGs encode the guanosine triphosphate cyclohydrolase 1 (GTPCH, a rate-limiting enzyme of pteridines biosynthesis. Neopterin, a stable byproduct of GTPCH-catalyzed reaction, is used as a marker of interferon-induced GTPCH activation. We hypothesized that assessment of neopterin concentrations might predict the response to antiviral therapy. Neopterin concentrations were evaluated in 260 HCV patients treated by pegylated interferon combined with ribavirin. Mean and median pretreatment neopterin concentrations were lower in patients with sustained virological response than in nonresponders. The rate of response was twofold higher among patients with pretreatment neopterin levels <16 nmol/L than in patients with neopterin levels ≥16 nmol/L, even after controlling for HCV genotype status. Our study suggests that the pretreatment level of neopterin might be used in routine clinical practice as rapid and cost-effective marker to predict the response to antiviral therapy in HCV patients.

  9. Coxsackievirus cloverleaf RNA containing a 5' triphosphate triggers an antiviral response via RIG-I activation.

    Science.gov (United States)

    Feng, Qian; Langereis, Martijn A; Olagnier, David; Chiang, Cindy; van de Winkel, Roel; van Essen, Peter; Zoll, Jan; Hiscott, John; van Kuppeveld, Frank J M

    2014-01-01

    Upon viral infections, pattern recognition receptors (PRRs) recognize pathogen-associated molecular patterns (PAMPs) and stimulate an antiviral state associated with the production of type I interferons (IFNs) and inflammatory markers. Type I IFNs play crucial roles in innate antiviral responses by inducing expression of interferon-stimulated genes and by activating components of the adaptive immune system. Although pegylated IFNs have been used to treat hepatitis B and C virus infections for decades, they exert substantial side effects that limit their use. Current efforts are directed toward the use of PRR agonists as an alternative approach to elicit host antiviral responses in a manner similar to that achieved in a natural infection. RIG-I is a cytosolic PRR that recognizes 5' triphosphate (5'ppp)-containing RNA ligands. Due to its ubiquitous expression profile, induction of the RIG-I pathway provides a promising platform for the development of novel antiviral agents and vaccine adjuvants. In this study, we investigated whether structured RNA elements in the genome of coxsackievirus B3 (CVB3), a picornavirus that is recognized by MDA5 during infection, could activate RIG-I when supplied with 5'ppp. We show here that a 5'ppp-containing cloverleaf (CL) RNA structure is a potent RIG-I inducer that elicits an extensive antiviral response that includes induction of classical interferon-stimulated genes, as well as type III IFNs and proinflammatory cytokines and chemokines. In addition, we show that prophylactic treatment with CVB3 CL provides protection against various viral infections including dengue virus, vesicular stomatitis virus and enterovirus 71, demonstrating the antiviral efficacy of this RNA ligand. PMID:24759703

  10. Coxsackievirus cloverleaf RNA containing a 5' triphosphate triggers an antiviral response via RIG-I activation.

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    Qian Feng

    Full Text Available Upon viral infections, pattern recognition receptors (PRRs recognize pathogen-associated molecular patterns (PAMPs and stimulate an antiviral state associated with the production of type I interferons (IFNs and inflammatory markers. Type I IFNs play crucial roles in innate antiviral responses by inducing expression of interferon-stimulated genes and by activating components of the adaptive immune system. Although pegylated IFNs have been used to treat hepatitis B and C virus infections for decades, they exert substantial side effects that limit their use. Current efforts are directed toward the use of PRR agonists as an alternative approach to elicit host antiviral responses in a manner similar to that achieved in a natural infection. RIG-I is a cytosolic PRR that recognizes 5' triphosphate (5'ppp-containing RNA ligands. Due to its ubiquitous expression profile, induction of the RIG-I pathway provides a promising platform for the development of novel antiviral agents and vaccine adjuvants. In this study, we investigated whether structured RNA elements in the genome of coxsackievirus B3 (CVB3, a picornavirus that is recognized by MDA5 during infection, could activate RIG-I when supplied with 5'ppp. We show here that a 5'ppp-containing cloverleaf (CL RNA structure is a potent RIG-I inducer that elicits an extensive antiviral response that includes induction of classical interferon-stimulated genes, as well as type III IFNs and proinflammatory cytokines and chemokines. In addition, we show that prophylactic treatment with CVB3 CL provides protection against various viral infections including dengue virus, vesicular stomatitis virus and enterovirus 71, demonstrating the antiviral efficacy of this RNA ligand.

  11. Integrative Genomics-Based Discovery of Novel Regulators of the Innate Antiviral Response

    NARCIS (Netherlands)

    Lee, R. van der; Feng, Q.; Langereis, M.A.; Horst, R. ter; Szklarczyk, R.J.; Netea, M.G.; Andeweg, A.C.; Kuppeveld, F.J.M. van; Huynen, M.A.

    2015-01-01

    The RIG-I-like receptor (RLR) pathway is essential for detecting cytosolic viral RNA to trigger the production of type I interferons (IFNalpha/beta) that initiate an innate antiviral response. Through systematic assessment of a wide variety of genomics data, we discovered 10 molecular signatures of

  12. Innate immunity to dengue virus infection and subversion of antiviral responses.

    Science.gov (United States)

    Green, Angela M; Beatty, P Robert; Hadjilaou, Alexandros; Harris, Eva

    2014-03-20

    Dengue is a major public health issue in tropical and subtropical regions worldwide. The four serotypes of dengue virus (DENV1-DENV4) are spread primarily by Aedes aegypti and Aedes albopictus mosquitoes, whose geographic range continues to expand. Humans are the only host for epidemic strains of DENV, and the virus has developed sophisticated mechanisms to evade human innate immune responses. The host cell's first line of defense begins with an intracellular signaling cascade resulting in production of interferon α/β (IFN-α/β), which promotes intracellular antiviral responses and helps initiates the adaptive response during the course of DENV infection. In response, DENV has developed numerous ways to subvert these intracellular antiviral responses and directly inhibit cellular signaling cascades. Specifically, DENV manipulates the unfolded protein response and autophagy to counter cellular stress and delay apoptosis. The DENV non-structural protein NS4B and subgenomic flavivirus RNA interfere with the RNA interference pathway by inhibiting the RNase Dicer. During heterotypic secondary DENV infection, subneutralizing antibodies can enable viral uptake through Fcγ receptors and down-regulate signaling cascades initiated via the pattern recognition receptors TLR-3 and MDA5/RIG-I, thus reducing the antiviral state of the cell. The DENV NS2B/3 protein cleaves human STING/MITA, interfering with induction of IFN-α/β. Finally, DENV NS2A, NS4A, and NS4B complex together to block STAT1 phosphorylation, while NS5 binds and promotes degradation of human STAT2, thus preventing formation of the STAT1/STAT2 heterodimer and its transcriptional induction of interferon stimulating genes. Here, we discuss the host innate immune response to DENV and the mechanisms of immune evasion that DENV has developed to manipulate cellular antiviral responses. PMID:24316047

  13. Applications of high-throughput genomics to antiviral research: evasion of antiviral responses and activation of inflammation during fulminant RNA virus infection

    OpenAIRE

    Kash, John C.

    2009-01-01

    Host responses can contribute to the severity of viral infection, through the failure of innate antiviral mechanisms to recognize and restrict the pathogen, the development of intense systemic inflammation leading to circulatory failure or through tissue injury resulting from overly exuberant cell-mediated immune responses. High-throughput genomics methods are now being used to identify the biochemical pathways underlying ineffective or damaging host responses in a number of acute and chronic...

  14. DMPD: The interferon-alpha/beta system in antiviral responses: a multimodal machineryof gene regulation by the IRF family of transcription factors. [Dynamic Macrophage Pathway CSML Database

    Lifescience Database Archive (English)

    Full Text Available 11790540 The interferon-alpha/beta system in antiviral responses: a multimodal mach...l. 2002 Feb;14(1):111-6. (.png) (.svg) (.html) (.csml) Show The interferon-alpha/beta system in antiviral responses: a multi...ion factors. PubmedID 11790540 Title The interferon-alpha/beta system in antiviral responses: a multimodal m

  15. Integrative Genomics-Based Discovery of Novel Regulators of the Innate Antiviral Response.

    Directory of Open Access Journals (Sweden)

    Robin van der Lee

    2015-10-01

    Full Text Available The RIG-I-like receptor (RLR pathway is essential for detecting cytosolic viral RNA to trigger the production of type I interferons (IFNα/β that initiate an innate antiviral response. Through systematic assessment of a wide variety of genomics data, we discovered 10 molecular signatures of known RLR pathway components that collectively predict novel members. We demonstrate that RLR pathway genes, among others, tend to evolve rapidly, interact with viral proteins, contain a limited set of protein domains, are regulated by specific transcription factors, and form a tightly connected interaction network. Using a Bayesian approach to integrate these signatures, we propose likely novel RLR regulators. RNAi knockdown experiments revealed a high prediction accuracy, identifying 94 genes among 187 candidates tested (~50% that affected viral RNA-induced production of IFNβ. The discovered antiviral regulators may participate in a wide range of processes that highlight the complexity of antiviral defense (e.g. MAP3K11, CDK11B, PSMA3, TRIM14, HSPA9B, CDC37, NUP98, G3BP1, and include uncharacterized factors (DDX17, C6orf58, C16orf57, PKN2, SNW1. Our validated RLR pathway list (http://rlr.cmbi.umcn.nl/, obtained using a combination of integrative genomics and experiments, is a new resource for innate antiviral immunity research.

  16. The response of sward-dwelling arthropod communities to reduced grassland management intensity in pastures

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    Helden Alvin J.

    2015-12-01

    Full Text Available We compared arthropod taxon richness, diversity and community structure of two replicated grassland husbandry experiments to investigate effects of reduced management intensity, as measured by nutrient input levels (390, 224 and 0 kg/ha per year N in one experiment, and 225 and 88 kg/ha per year N in another. Suction sampling was used to collect Araneae, Coleoptera, Hemiptera and Hymenoptera, with Araneae and Coleoptera also sampled with pitfall trapping. Univariate analyses found no significant differences in abundance and species density between treatments. However, with multivariate analysis, there were significant differences in arthropod community structure between treatments in both experiments.

  17. Systems-Biology Approaches to Discover Anti-Viral Effectors of the Human Innate Immune Response

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    Andreas F.R. Sommer

    2011-07-01

    Full Text Available Virus infections elicit an immediate innate response involving antiviral factors. The activities of some of these factors are, in turn, blocked by viral countermeasures. The ensuing battle between the host and the viruses is crucial for determining whether the virus establishes a foothold and/or induces adaptive immune responses. A comprehensive systems-level understanding of the repertoire of anti-viral effectors in the context of these immediate virus-host responses would provide significant advantages in devising novel strategies to interfere with the initial establishment of infections. Recent efforts to identify cellular factors in a comprehensive and unbiased manner, using genome-wide siRNA screens and other systems biology “omics” methodologies, have revealed several potential anti-viral effectors for viruses like Human immunodeficiency virus type 1 (HIV-1, Hepatitis C virus (HCV, West Nile virus (WNV, and influenza virus. This review describes the discovery of novel viral restriction factors and discusses how the integration of different methods in systems biology can be used to more comprehensively identify the intimate interactions of viruses and the cellular innate resistance.

  18. A heritable antiviral RNAi response limits Orsay virus infection in Caenorhabditis elegans N2.

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    Mark G Sterken

    Full Text Available Orsay virus (OrV is the first virus known to be able to complete a full infection cycle in the model nematode species Caenorhabditis elegans. OrV is transmitted horizontally and its infection is limited by antiviral RNA interference (RNAi. However, we have no insight into the kinetics of OrV replication in C. elegans. We developed an assay that infects worms in liquid, allowing precise monitoring of the infection. The assay revealed a dual role for the RNAi response in limiting Orsay virus infection in C. elegans. Firstly, it limits the progression of the initial infection at the step of recognition of dsRNA. Secondly, it provides an inherited protection against infection in the offspring. This establishes the heritable RNAi response as anti-viral mechanism during OrV infections in C. elegans. Our results further illustrate that the inheritance of the anti-viral response is important in controlling the infection in the canonical wild type Bristol N2. The OrV replication kinetics were established throughout the worm life-cycle, setting a standard for further quantitative assays with the OrV-C. elegans infection model.

  19. Cellular immune responses in patients with hepatitis B surface antigen seroclearance induced by antiviral therapy

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    Zhu Xiaolin

    2011-02-01

    Full Text Available Abstract Background The mechanisms by which chronic hepatitis B is completely resolved through antiviral therapy are unknown, and the contribution of acquired T cell immunity to hepatitis B surface antigen (HBsAg seroclearance has not been investigated. Therefore, we measured the T-cell responses to core and envelope antigens in patients with HBsAg seroclearance. Methods Fourteen subjects with HBsAg seroclearance following antiviral treatment for chronic hepatitis B, 7 HBeAg-positive immunotolerant HBV carriers and 9 HBeAg-negative inactive HBsAg carriers were recruited. HBV-specific T-cell responses to recombinant HBV core (rHBcAg and envelope (rHBsAg proteins and pools of core and envelope peptides were measured using an ELISPOT assay detecting interferon-gamma and intracellular cytokine staining (ICS assays detecting interferon-gamma or interleukin 2. Results Interferon-gamma ELISPOT assays showed a low frequency of weak responses to the rHBsAg and S peptide pool in the HBsAg seroclearance group, and the response frequency to the rHBcAg and the C peptide pool was higher than to the rHBsAg (P P = 0.001 respectively. A higher response frequency to C than S peptide pools was confirmed in the interferon-gamma ICS assays for both CD4+ (P = 0.033 and CD8+ (P = 0.040 T cells in the HBsAg seroclearance group. The responses to C and S antigens in the inactive carriers were similar. Conclusions There was a low frequency of CD4+ and CD8+ T cell immune responses to envelope antigens in Chinese subjects with HBsAg seroclearance following antiviral therapy. It is unlikely that these immune responses are responsible for HBsAg seroclearance in these subjects.

  20. Original Antigenic Sin Response to RNA Viruses and Antiviral Immunity

    Science.gov (United States)

    Park, Mee Sook; Kim, Jin Il; Park, Sehee; Lee, Ilseob

    2016-01-01

    The human immune system has evolved to fight against foreign pathogens. It plays a central role in the body's defense mechanism. However, the immune memory geared to fight off a previously recognized pathogen, tends to remember an original form of the pathogen when a variant form subsequently invades. This has been termed 'original antigenic sin'. This adverse immunological effect can alter vaccine effectiveness and sometimes cause enhanced pathogenicity or additional inflammatory responses, according to the type of pathogen and the circumstances of infection. Here we aim to give a simplified conceptual understanding of virus infection and original antigenic sin by comparing and contrasting the two examples of recurring infections such as influenza and dengue viruses in humans. PMID:27799871

  1. Beyond RNAi: antiviral defense strategies in Drosophila and mosquito

    NARCIS (Netherlands)

    Merkling, S.H.; Rij, R.P. van

    2013-01-01

    Virus transmission and spread by arthropods is a major economic and public health concern. The ongoing dissemination of arthropod-borne viruses by blood-feeding insects is an important incentive to study antiviral immunity in these animals. RNA interference is a major mechanism for antiviral defense

  2. Intrathecal, polyspecific antiviral immune response in oligoclonal band negative multiple sclerosis.

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    Isabel Brecht

    Full Text Available BACKGROUND: Oligoclonal bands (OCB are detected in the cerebrospinal fluid (CSF in more than 95% of patients with multiple sclerosis (MS in the Western hemisphere. Here we evaluated the intrathecal, polyspecific antiviral immune response as a potential diagnostic CSF marker for OCB-negative MS patients. METHODOLOGY/PRINCIPAL FINDINGS: We tested 46 OCB-negative German patients with paraclinically well defined, definite MS. Sixteen OCB-negative patients with a clear diagnosis of other autoimmune CNS disorders and 37 neurological patients without evidence for autoimmune CNS inflammation served as control groups. Antibodies against measles, rubella, varicella zoster and herpes simplex virus in paired serum and CSF samples were determined by ELISA, and virus-specific immunoglobulin G antibody indices were calculated. An intrathecal antibody synthesis against at least one neurotropic virus was detected in 8 of 26 (31% patients with relapsing-remitting MS, 8 of 12 (67% with secondary progressive MS and 5 of 8 (63% with primary progressive MS, in 3 of 16 (19% CNS autoimmune and 3 of 37 (8% non-autoimmune control patients. Antibody synthesis against two or more viruses was found in 11 of 46 (24% MS patients but in neither of the two control groups. On average, MS patients with a positive antiviral immune response were older and had a longer disease duration than those without. CONCLUSION: Determination of the intrathecal, polyspecific antiviral immune response may allow to establish a CSF-supported diagnosis of MS in OCB-negative patients when two or more of the four virus antibody indices are elevated.

  3. Estrogen receptor 2b deficiency impairs the antiviral response of zebrafish.

    Science.gov (United States)

    López-Muñoz, Azucena; Liarte, Sergio; Gómez-González, Nuria E; Cabas, Isabel; Meseguer, José; García-Ayala, Alfonsa; Mulero, Victoriano

    2015-11-01

    Although several studies have demonstrated the ability of some endocrine disruptive chemicals (EDCs) to alter the physiology of zebrafish, the immune-reproductive interaction has received little attention in this species. In this study, we used a homozygous line carrying an insertion of 8 amino acids in the ligand-binding domain of the estrogen receptor 2b gene (esr2b) to further understand the role of estrogen signaling on innate immunity. Adult mutant fish showed distorted sexual ratios related with alterations in testicular morphology and supraphysiological testosterone and 17β-estradiol (E2) levels. Immunity-wise, although esr2b mutant fish showed unaltered antibacterial responses, they were unable to mount an effective antiviral response upon viral challenge. RT-qPCR analysis demonstrated that mutant fish were able to induce the genes encoding major antiviral molecules, including Ifnphi1, Ifnphi2, Infphi3, Mxb and Mxc, and the negative feedback regulator of cytokine signaling Socs1. Notably, although esr2b mutant larvae showed a similar resistance to SVCV infection to their wild type siblings, waterborne E2 increased their viral susceptibility. Similarly, the exposure of adult wild type zebrafish to E2 also resulted in increased susceptibility to SVCV infection. Finally, the administration of recombinant Ifnphi1 hardly reversed the higher viral susceptibility of esr2b mutant zebrafish, suggesting that elevated socs1 levels impair Ifn signaling. All together, these results uncover an important role for E2 and Esr signaling in the fine-tuning of sexual hormone balance and the antiviral response of vertebrates.

  4. The ubiquitin ligase RNF5 regulates antiviral responses by mediating degradation of the adaptor protein MITA.

    Science.gov (United States)

    Zhong, Bo; Zhang, Lu; Lei, Caoqi; Li, Ying; Mao, Ai-Ping; Yang, Yan; Wang, Yan-Yi; Zhang, Xiao-Lian; Shu, Hong-Bing

    2009-03-20

    Viral infection activates transcription factors NF-kappaB and IRF3, which collaborate to induce type I interferons (IFNs) and elicit innate antiviral response. MITA (also known as STING) has recently been identified as an adaptor that links virus-sensing receptors to IRF3 activation. Here, we showed that the E3 ubiquitin ligase RNF5 interacted with MITA in a viral-infection-dependent manner. Overexpression of RNF5 inhibited virus-triggered IRF3 activation, IFNB1 expression, and cellular antiviral response, whereas knockdown of RNF5 had opposite effects. RNF5 targeted MITA at Lys150 for ubiquitination and degradation after viral infection. Both MITA and RNF5 were located at the mitochondria and endoplasmic reticulum (ER) and viral infection caused their redistribution to the ER and mitochondria, respectively. We further found that virus-induced ubiquitination and degradation of MITA by RNF5 occurred at the mitochondria. These findings suggest that RNF5 negatively regulates virus-triggered signaling by targeting MITA for ubiquitination and degradation at the mitochondria.

  5. Epigenetic reprogramming of the type III interferon response potentiates antiviral activity and suppresses tumor growth.

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    Siyuan Ding

    2014-01-01

    Full Text Available Type III interferon (IFN-λ exhibits potent antiviral activity similar to IFN-α/β, but in contrast to the ubiquitous expression of the IFN-α/β receptor, the IFN-λ receptor is restricted to cells of epithelial origin. Despite the importance of IFN-λ in tissue-specific antiviral immunity, the molecular mechanisms responsible for this confined receptor expression remain elusive. Here, we demonstrate that the histone deacetylase (HDAC repression machinery mediates transcriptional silencing of the unique IFN-λ receptor subunit (IFNLR1 in a cell-type-specific manner. Importantly, HDAC inhibitors elevate receptor expression and restore sensitivity to IFN-λ in previously nonresponsive cells, thereby enhancing protection against viral pathogens. In addition, blocking HDAC activity renders nonresponsive cell types susceptible to the pro-apoptotic activity of IFN-λ, revealing the combination of HDAC inhibitors and IFN-λ to be a potential antitumor strategy. These results demonstrate that the type III IFN response may be therapeutically harnessed by epigenetic rewiring of the IFN-λ receptor expression program.

  6. The Imd pathway is involved in antiviral immune responses in Drosophila.

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    Alexandre Costa

    Full Text Available Cricket Paralysis virus (CrPV is a member of the Dicistroviridae family of RNA viruses, which infect a broad range of insect hosts, including the fruit fly Drosophila melanogaster. Drosophila has emerged as an effective system for studying innate immunity because of its powerful genetic techniques and the high degree of gene and pathway conservation. Intra-abdominal injection of CrPV into adult flies causes a lethal infection that provides a robust assay for the identification of mutants with altered sensitivity to viral infection. To gain insight into the interactions between viruses and the innate immune system, we injected wild type flies with CrPV and observed that antimicrobial peptides (AMPs were not induced and hemocytes were depleted in the course of infection. To investigate the contribution of conserved immune signaling pathways to antiviral innate immune responses, CrPV was injected into isogenic mutants of the Immune Deficiency (Imd pathway, which resembles the mammalian Tumor Necrosis Factor Receptor (TNFR pathway. Loss-of-function mutations in several Imd pathway genes displayed increased sensitivity to CrPV infection and higher CrPV loads. Our data show that antiviral innate immune responses in flies infected with CrPV depend upon hemocytes and signaling through the Imd pathway.

  7. Is sustained virological response a marker of treatment efficacy in patients with chronic hepatitis C viral infection with no response or relapse to previous antiviral intervention?

    DEFF Research Database (Denmark)

    Gurusamy, Kurinchi S; Wilson, Edward; Koretz, Ronald L;

    2013-01-01

    Randomised clinical trials (RCTs) of antiviral interventions in patients with chronic hepatitis C virus (HCV) infection use sustained virological response (SVR) as the main outcome. There is sparse information on long-term mortality from RCTs....

  8. Genotype 1 hepatitis C virus envelope features that determine antiviral response assessed through optimal covariance networks.

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    John M Murray

    Full Text Available The poor response to the combined antiviral therapy of pegylated alfa-interferon and ribavarin for hepatitis C virus (HCV infection may be linked to mutations in the viral envelope gene E1E2 (env, which can result in escape from the immune response and higher efficacy of viral entry. Mutations that result in failure of therapy most likely require compensatory mutations to achieve sufficient change in envelope structure and function. Compensatory mutations were investigated by determining positions in the E1E2 gene where amino acids (aa covaried across groups of individuals. We assessed networks of covarying positions in E1E2 sequences that differentiated sustained virological response (SVR from non-response (NR in 43 genotype 1a (17 SVR, and 49 genotype 1b (25 SVR chronically HCV-infected individuals. Binary integer programming over covariance networks was used to extract aa combinations that differed between response groups. Genotype 1a E1E2 sequences exhibited higher degrees of covariance and clustered into 3 main groups while 1b sequences exhibited no clustering. Between 5 and 9 aa pairs were required to separate SVR from NR in each genotype. aa in hypervariable region 1 were 6 times more likely than chance to occur in the optimal networks. The pair 531-626 (EI appeared frequently in the optimal networks and was present in 6 of 9 NR in one of the 1a clusters. The most frequent pairs representing SVR were 431-481 (EE, 500-522 (QA in 1a, and 407-434 (AQ in 1b. Optimal networks based on covarying aa pairs in HCV envelope can indicate features that are associated with failure or success to antiviral therapy.

  9. Novel immune genes associated with excessive inflammatory and antiviral responses to rhinovirus in COPD

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    Baines Katherine J

    2013-02-01

    Full Text Available Abstract Background Rhinovirus (RV is a major cause of chronic obstructive pulmonary disease (COPD exacerbations, and primarily infects bronchial epithelial cells. Immune responses from BECs to RV infection are critical in limiting viral replication, and remain unclear in COPD. The objective of this study is to investigate innate immune responses to RV infection in COPD primary BECs (pBECs in comparison to healthy controls. Methods Primary bronchial epithelial cells (pBECs from subjects with COPD and healthy controls were infected with RV-1B. Cells and cell supernatant were collected and analysed using gene expression microarray, qPCR, ELISA, flow cytometry and titration assay for viral replication. Results COPD pBECs responded to RV-1B infection with an increased expression of antiviral and pro-inflammatory genes compared to healthy pBECs, including cytokines, chemokines, RNA helicases, and interferons (IFNs. Similar levels of viral replication were observed in both disease groups; however COPD pBECs were highly susceptible to apoptosis. COPD pBECs differed at baseline in the expression of 9 genes, including calgranulins S100A8/A9, and 22 genes after RV-1B infection including the signalling proteins pellino-1 and interleukin-1 receptor associated kinase 2. In COPD, IFN-β/λ1 pre-treatment did not change MDA-5/RIG-I and IFN-β expression, but resulted in higher levels IFN-λ1, CXCL-10 and CCL-5. This led to reduced viral replication, but did not increase pro-inflammatory cytokines. Conclusions COPD pBECs elicit an exaggerated pro-inflammatory and antiviral response to RV-1B infection, without changing viral replication. IFN pre-treatment reduced viral replication. This study identified novel genes and pathways involved in potentiating the inflammatory response to RV in COPD.

  10. Pyruvate Carboxylase Activates the RIG-I-like Receptor-Mediated Antiviral Immune Response by Targeting the MAVS signalosome

    Science.gov (United States)

    Cao, Zhongying; Zhou, Yaqin; Zhu, Shengli; Feng, Jian; Chen, Xueyuan; Liu, Shi; Peng, Nanfang; Yang, Xiaodan; Xu, Gang; Zhu, Ying

    2016-01-01

    When retinoic acid-inducible gene 1 protein (RIG-I)-like receptors sense viral dsRNA in the cytosol, RIG-I and melanoma differentiation-associated gene 5 (MDA5) are recruited to the mitochondria to interact with mitochondrial antiviral signaling protein (MAVS) and initiate antiviral immune responses. In this study, we demonstrate that the biotin-containing enzyme pyruvate carboxylase (PC) plays an essential role in the virus-triggered activation of nuclear factor kappa B (NF-κB) signaling mediated by MAVS. PC contributes to the enhanced production of type I interferons (IFNs) and pro-inflammatory cytokines, and PC knockdown inhibits the virus-triggered innate immune response. In addition, PC shows extensive antiviral activity against RNA viruses, including influenza A virus (IAV), human enterovirus 71 (EV71), and vesicular stomatitis virus (VSV). Furthermore, PC mediates antiviral action by targeting the MAVS signalosome and induces IFNs and pro-inflammatory cytokines by promoting phosphorylation of NF-κB inhibitor-α (IκBα) and the IκB kinase (IKK) complex, as well as NF-κB nuclear translocation, which leads to activation of interferon-stimulated genes (ISGs), including double-stranded RNA-dependent protein kinase (PKR) and myxovirus resistance protein 1 (Mx1). Our findings suggest that PC is an important player in host antiviral signaling. PMID:26906558

  11. The Role of Cytokine PF4 in the Antiviral Immune Response of Shrimp

    Science.gov (United States)

    Chen, Yulei; Cao, Jiao; Zhang, Xiaobo

    2016-01-01

    During viral infection in vertebrates, cytokines play important roles in the host defense against the virus. However, the function of cytokines in invertebrates has not been well characterized. In this study, shrimp cytokines involved in viral infection were screened using a cytokine antibody microarray. The results showed that three cytokines, the Fas receptor (Fas), platelet factor 4 (PF4) and interleukin-22 (IL-22), were significantly upregulated in the white spot syndrome virus (WSSV)-challenged shrimp, suggesting that these cytokines played positive regulatory roles in the immune response of shrimp against the virus. Further experiments revealed that PF4 had positive effects on the antiviral immunity of shrimp by enhancing the shrimp phagocytic activity and inhibiting the apoptotic activity of virus-infected hemocytes. Therefore, our study presented a novel mechanism of cytokines in the innate immunity of invertebrates. PMID:27631372

  12. Antiviral activity of a small molecule deubiquitinase inhibitor occurs via induction of the unfolded protein response.

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    Jeffrey W Perry

    Full Text Available Ubiquitin (Ub is a vital regulatory component in various cellular processes, including cellular responses to viral infection. As obligate intracellular pathogens, viruses have the capacity to manipulate the ubiquitin (Ub cycle to their advantage by encoding Ub-modifying proteins including deubiquitinases (DUBs. However, how cellular DUBs modulate specific viral infections, such as norovirus, is poorly understood. To examine the role of DUBs during norovirus infection, we used WP1130, a small molecule inhibitor of a subset of cellular DUBs. Replication of murine norovirus in murine macrophages and the human norovirus Norwalk virus in a replicon system were significantly inhibited by WP1130. Chemical proteomics identified the cellular DUB USP14 as a target of WP1130 in murine macrophages, and pharmacologic inhibition or siRNA-mediated knockdown of USP14 inhibited murine norovirus infection. USP14 is a proteasome-associated DUB that also binds to inositol-requiring enzyme 1 (IRE1, a critical mediator of the unfolded protein response (UPR. WP1130 treatment of murine macrophages did not alter proteasome activity but activated the X-box binding protein-1 (XBP-1 through an IRE1-dependent mechanism. In addition, WP1130 treatment or induction of the UPR also reduced infection of other RNA viruses including encephalomyocarditis virus, Sindbis virus, and La Crosse virus but not vesicular stomatitis virus. Pharmacologic inhibition of the IRE1 endonuclease activity partially rescued the antiviral effect of WP1130. Taken together, our studies support a model whereby induction of the UPR through cellular DUB inhibition blocks specific viral infections, and suggest that cellular DUBs and the UPR represent novel targets for future development of broad spectrum antiviral therapies.

  13. Negative regulation of the innate antiviral immune response by TRIM62 from orange spotted grouper.

    Science.gov (United States)

    Yang, Ying; Huang, Youhua; Yu, Yepin; Zhou, Sheng; Wang, Shaowen; Yang, Min; Qin, Qiwei; Huang, Xiaohong

    2016-10-01

    Increased reports uncovered that mammalian tripartite motif-containing 62 (TRIM62) exerts crucial roles in cancer and innate immune response. However, the roles of fish TRIM62 in antiviral immune response remained uncertain. In this study, a TRIM62 gene was cloned from orange spotted grouper (EcTRIM62) and its roles in grouper RNA virus infection was elucidated in vitro. EcTRIM62 shared 99% and 83% identity to bicolor damselfish (Stegastes partitus) and human (Homo sapiens), respectively. Sequence alignment indicated that EcTRIM62 contained three domains, including a RING-finger domain, a B-box domain and a SPRY domain. In healthy grouper, the transcript of EcTRIM62 was predominantly detected in brain and liver, followed by heart, skin, spleen, fin, gill, intestine, and stomach. Subcellular localization analysis indicated that bright fluorescence spots were observed in the cytoplasm of EcTRIM62-transfected grouper spleen (GS) cells. During red-spotted grouper nervous necrosis (RGNNV) infection, overexpression of EcTRIM62 significantly enhanced the severity of CPE and increased viral gene transcriptions. Furthermore, the ectopic expression of EcTRIM62 significantly decreased the transcription level of interferon signaling molecules, including interferon regulatory factor 3 (IRF3), IRF7, interferon-stimulated gene 15 (ISG15), melanoma differentiation-associated protein 5 (MDA5), myxovirus resistance gene MXI, and MXII, suggesting that the negative regulation of interferon immune response by EcTRIM62 might directly contributed to its enhancing effect on RGNNV replication. Furthermore, our results also demonstrated that overexpression of EcTRIM62 was able to differently regulate the expression levels of pro-inflammation cytokines. In addition, we found the ectopic expression of EcTIRM62 negatively regulated MDA5-, but not mediator of IRF3 activation (MITA)-induced interferon immune response. Further studies showed that the deletion of RING domain and SPRY domain

  14. TNFα Impairs Rhabdoviral Clearance by Inhibiting the Host Autophagic Antiviral Response

    Science.gov (United States)

    Roca, Francisco J.; López-Muñoz, Azucena; Tyrkalska, Sylwia D.; Candel, Sergio; García-Moreno, Diana; Falco, Alberto; Meseguer, José

    2016-01-01

    TNFα is a pleiotropic pro-inflammatory cytokine with a key role in the activation of the immune system to fight viral infections. Despite its antiviral role, a few viruses might utilize the host produced TNFα to their benefit. Some recent reports have shown that anti-TNFα therapies could be utilized to treat certain viral infections. However, the underlying mechanisms by which TNFα can favor virus replication have not been identified. Here, a rhabdoviral infection model in zebrafish allowed us to identify the mechanism of action by which Tnfa has a deleterious role for the host to combat certain viral infections. Our results demonstrate that Tnfa signals through its receptor Tnfr2 to enhance viral replication. Mechanistically, Tnfa does not affect viral adhesion and delivery from endosomes to the cytosol. In addition, the host interferon response was also unaffected by Tnfa levels. However, Tnfa blocks the host autophagic response, which is required for viral clearance. This mechanism of action provides new therapeutic targets for the treatment of SVCV-infected fish, and advances our understanding of the previously enigmatic deleterious role of TNFα in certain viral infections. PMID:27351838

  15. LSm14A Plays a Critical Role in Antiviral Immune Responses by Regulating MITA Level in a Cell-Specific Manner.

    Science.gov (United States)

    Liu, Tian-Tian; Yang, Qing; Li, Mi; Zhong, Bo; Ran, Yong; Liu, Li-Li; Yang, Yan; Wang, Yan-Yi; Shu, Hong-Bing

    2016-06-15

    Viral infection triggers induction of antiviral cytokines and effectors, which are critical mediators of innate antiviral immune response. It has been shown that the processing body-associated protein LSm14A is involved in the induction of antiviral cytokines in cell lines but in vivo evidence is lacking. By generating LSm14A-deficient mice, in this study, we show that LSm14A plays a critical and specific role in the induction of antiviral cytokines in dendritic cells (DCs) but not in macrophages and fibroblasts. Induction of antiviral cytokines triggered by the DNA viruses HSV-1 and murid herpesvirus 68 and the RNA virus vesicular stomatitis virus but not Sendai virus was impaired in Lsm14a(-/-) DCs, which is correlated to the functions of the adaptor protein MITA/STING in the antiviral signaling pathways. LSm14A deficiency specifically downregulated MITA/STING level in DCs by impairing its nuclear mRNA precursor processing and subsequently impaired antiviral innate and adaptive immune responses. Our findings reveal a nuclear mRNA precursor processing and cell-specific regulatory mechanism of antiviral immune responses.

  16. HDAC1 controls CD8+ T cell homeostasis and antiviral response.

    Directory of Open Access Journals (Sweden)

    Roland Tschismarov

    Full Text Available Reversible lysine acetylation plays an important role in the regulation of T cell responses. HDAC1 has been shown to control peripheral T helper cells, however the role of HDAC1 in CD8+ T cell function remains elusive. By using conditional gene targeting approaches, we show that LckCre-mediated deletion of HDAC1 led to reduced numbers of thymocytes as well as peripheral T cells, and to an increased fraction of CD8+CD4- cells within the CD3/TCRβlo population, indicating that HDAC1 is essential for the efficient progression of immature CD8+CD4- cells to the DP stage. Moreover, CD44hi effector CD8+ T cells were enhanced in mice with a T cell-specific deletion of HDAC1 under homeostatic conditions and HDAC1-deficient CD44hi CD8+ T cells produced more IFNγ upon ex vivo PMA/ionomycin stimulation in comparison to wild-type cells. Naïve (CD44l°CD62L+ HDAC1-null CD8+ T cells displayed a normal proliferative response, produced similar amounts of IL-2 and TNFα, slightly enhanced amounts of IFNγ, and their in vivo cytotoxicity was normal in the absence of HDAC1. However, T cell-specific loss of HDAC1 led to a reduced anti-viral CD8+ T cell response upon LCMV infection and impaired expansion of virus-specific CD8+ T cells. Taken together, our data indicate that HDAC1 is required for the efficient generation of thymocytes and peripheral T cells, for proper CD8+ T cell homeostasis and for an efficient in vivo expansion and activation of CD8+ T cells in response to LCMV infection.

  17. Grouper TRIM13 exerts negative regulation of antiviral immune response against nodavirus.

    Science.gov (United States)

    Huang, Youhua; Yang, Min; Yu, Yepin; Yang, Ying; Zhou, Linli; Huang, Xiaohong; Qin, Qiwei

    2016-08-01

    -inflammatory factors. Together, our results firstly demonstrated that fish TRIM13 exerted negative regulation of antiviral response against nodavirus infection.

  18. Contribution of Herpesvirus Specific CD8 T Cells to Anti-Viral T Cell Response in Humans

    OpenAIRE

    Elena Sandalova; Diletta Laccabue; Carolina Boni; Tan, Anthony T.; Katja Fink; Eng Eong Ooi; Robert Chua; Bahar Shafaeddin Schreve; Carlo Ferrari; Antonio Bertoletti

    2010-01-01

    Herpesviruses infect most humans. Their infections can be associated with pathological conditions and significant changes in T cell repertoire but evidences of symbiotic effects of herpesvirus latency have never been demonstrated. We tested the hypothesis that HCMV and EBV-specific CD8 T cells contribute to the heterologous anti-viral immune response. Volume of activated/proliferating virus-specific and total CD8 T cells was evaluated in 50 patients with acute viral infections: 20 with HBV, 1...

  19. N-P Co-Limitation of Primary Production and Response of Arthropods to N and P in Early Primary Succession on Mount St. Helens Volcano

    Science.gov (United States)

    Bishop, John G.; O'Hara, Niamh B.; Titus, Jonathan H.; Apple, Jennifer L.; Gill, Richard A.; Wynn, Louise

    2010-01-01

    Background The effect of low nutrient availability on plant-consumer interactions during early succession is poorly understood. The low productivity and complexity of primary successional communities are expected to limit diversity and abundance of arthropods, but few studies have examined arthropod responses to enhanced nutrient supply in this context. We investigated the effects of nitrogen (N) and phosphorus (P) addition on plant productivity and arthropod abundance on 24-yr-old soils at Mount St. Helens volcano. Methodology/Principal Findings We measured the relative abundance of eight arthropod orders and five families in plots that received N, P, or no nutrients for 3–5 years. We also measured plant % cover, leaf %N, and plant diversity. Vegetation responded rapidly to N addition but showed a lagged response to P that, combined with evidence of increased N fixation, suggested P-limitation to N availability. After 3 yrs of fertilization, orthopterans (primarily Anabrus simplex (Tettigoniidae) and Melanoplus spp (Acrididae)) showed a striking attraction to P addition plots, while no other taxa responded to fertilization. After 5 yrs of fertilization, orthopteran density in the same plots increased 80%–130% with P addition and 40% with N. Using structural equation modeling, we show that in year 3 orthopteran abundance was associated with a P-mediated increase in plant cover (or correlated increases in resource quality), whereas in year 5 orthopteran density was not related to cover, diversity or plant %N, but rather to unmeasured effects of P, such as its influence on other aspects of resource quality. Conclusions/Significance The marked surprising response to P by orthopterans, combined with a previous observation of P-limitation in lepidopteran herbivores at these sites, suggests that P-mediated effects of food quantity or quality are critical to insect herbivores in this N-P co-limited primary successional system. Our results also support a previous

  20. Secondary succession of arthropods and plants in the Arizona Sonoran Desert in response to transmission line construction

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, C.D.; Beley, J.R.; Ditsworth, T.M.; Butt, S.M.

    1983-03-01

    At a site about 16 km south of Black Canyon City, Arizona, density of arthropods on an undisturbed plot after an access road was built for powerline construction was much greater than on a disturbed plot. Mites, springtails, leafhoppers, scale insects, ants and thrips were signficantly reduced on the disturbed area. Our results indicate that restoration of numbers of arthropods on the disturbed area is dependent on the total plant cover on the plot, apparently regardless of the composition of the plant species involved. It is obvious in this area that the plant communities will remain dissimilar, with the pioneering herbaceous plants on the disturbed plot dominating. Cosntruction of a powerline apparently has had little impact on the structure of the arthropod community on the disturbed area, as proportions of three trophic categories of arthropods have not been radically altered. The results of this study, when compared to other studies in the Sonoran Desert and in desert grasslands disturbed by powerline construction, indicate that lengthy secondary succession does occur in the Sonoran Desert. Early arthropod invaders were found to be mainly herbivores, with few parasites or predators, and an equilibrium was eventually reached between colonizers and space requirements.

  1. IL28B polymorphism as a predictor of antiviral response in chronic hepatitis C

    Institute of Scientific and Technical Information of China (English)

    Andrzej Cie(s)la; Monika Bociaga-Jasik; Iwona Sobczyk-Krupiarz; Miko(l)aj K G(l)owacki; Danuta Owczarek; Dorota Cibor; Marek Sanak

    2012-01-01

    AIM:To evaluate the effect of single nucleotide polymorphisms of interleukin (IL)-28B,rs12979860 on progression and treatment response in chronic hepatitis C.METHODS:Patients (n =64; 37 men,27 women;mean age,44 ± 12 years) with chronic hepatitis C,genotype 1,received treatment with peg-interferon plus ribavirin.Genotyping of rs12979860 was performed on peripheral blood DNA.Histopathological assessment of necroinflammatory grade and fibrosis stage were scored using the METAVIR system on a liver biopsy sample before treatment.Serum viral load,aminotransferase activity,and insulin level were measured.Insulin resistance index,body mass index,waist/hip ratio,percentage of body fat and fibrosis progression rate were calculated.Applied dose of interferon and ribavirin,platelet and neutrophil count and hemoglobin level were measured.RESULTS:A sustained virological response (SVR) was significantly associated with IL28B polymorphism (CC vs TT allele:odds ratio (OR),25; CC vs CT allele:OR,5.4),inflammation activity (G < 1 vs G > 1:OR,3.9),fibrosis (F < 1 vs F > 1:OR,5.9),platelet count (> 200× 109/L vs < 200 × 109/L:OR,4.7; OR in patients with genotype CT:12.8),fatty liver (absence vs presence of steatosis:OR,4.8),insulin resistance index (< 2.5 vs >2.5:OR,3.9),and baseline HCV viral load (< 106 IU/mL vs > 106 IU/mL:OR,3.0).There was no association with age,sex,aminotransferases activity,body mass index,waist/hip ratio,or percentage body fat.There was borderline significance (P =0.064) of increased fibrosis in patients with the TT allele,and no differences in the insulin resistance index between groups of patients with CC,CT and TT alleles (P =0.12).Spearman's rank correlation coefficient between insulin resistance and stage of fibrosis and body mass index was r =0.618 and r =0.605,respectively (P < 0.001).Significant differences were found in the insulin resistance index (P =0.01) between patients with and without steatosis.Patients with the CT

  2. Negative regulation of the antiviral response by grouper LGP2 against fish viruses.

    Science.gov (United States)

    Yu, Yepin; Huang, Youhua; Yang, Ying; Wang, Shaowen; Yang, Min; Huang, Xiaohong; Qin, Qiwei

    2016-09-01

    Laboratory of genetics and physiology 2 (LGP2), a member of RIG-I like receptor (RLR) family, plays crucial roles in modulating cellular antiviral response during viral infection. However, the detailed roles of LGP2 in different virus infection were controversial up to now. Here, we cloned a LGP2 gene from orange-spotted grouper (EcLGP2) and investigated its roles in response to grouper virus infection. EcLGP2 encoded a 678-aa protein which shared 83% identity to sea perch (Lateolabrax japonicas). Amino acid alignment showed that EcLGP2 contained three conserved domains, including a DEAD/DEAH box helicase domain, a helicase superfamily C-terminal domain and a C-terminal domain of RIG-I. In healthy grouper, the transcript of EcLGP2 could be predominantly detected in kidney, gill, fin, spleen and skin. Subcellular localization analysis showed that EcLGP2 distributed throughout the cytoplasm in grouper cells. Notably, the intracellular distribution of EcLGP2 was altered at the late stage of Singapore grouper iridovirus (SGIV) infection, but remained unchanged during red-spotted grouper nervous necrosis virus (RGNNV) infection. Moreover, overexpression of EcLGP2 in vitro significantly enhanced the viral replication of SGIV and RGNNV, evidenced by the acceleration of CPE occurrence and the up-regulation of the viral gene transcription or protein synthesis. Further studies indicated that overexpression of EcLGP2 decreased the expression level of interferon related molecules or effectors, including IRF3, IRF7, ISG15, IFP35, MXI, MXII, and MDA5, suggesting that the negative feedback of interferon immune response by EcLGP2 might contribute to the enhancement of RGNNV infection. Moreover, the expression levels of pro-inflammation cytokines, including IL-8 and TNFα were significantly decreased, but that of IL-6 was increased by the ectopic expression of EcLGP2. Thus, our results will contribute greatly to understanding the roles of fish LGP2 in innate immune response during

  3. Accessory factors of cytoplasmic viral RNA sensors required for antiviral innate immune response

    Directory of Open Access Journals (Sweden)

    Hiroyuki eOshiumi

    2016-05-01

    Full Text Available Type I interferon (IFN induces many antiviral factors in host cells. RIG-I-like receptors (RLRs are cytoplasmic viral RNA sensors that trigger the signal to induce the innate immune response that includes type I IFN production. RIG-I and MDA5 are RLRs that form nucleoprotein filaments along viral double-stranded RNA, resulting in the activation of MAVS adaptor molecule. The MAVS protein forms a prion-like aggregation structure, leading to type I IFN production. RIG-I and MDA5 undergo post-translational modification. TRIM25 and Riplet ubiquitin ligases deliver a K63-linked polyubiquitin moiety to the RIG-I N-terminal caspase activation and recruitment domains (CARDs and C-terminal region; the polyubiquitin chain then stabilizes the two-CARD tetramer structure required for MAVS assembly. MDA5 activation is regulated by phosphorylation. RIOK3 is a protein kinase that phosphorylates the MDA5 protein in a steady state, and PP1α/γ dephosphorylate this protein, resulting in its activation. RIG-I and MDA5 require cytoplasmic RNA helicases for their efficient activation. LGP2, another RLR, is an RNA helicase involved in RLR signaling. This protein does not possess N-terminal CARDs and thus cannot trigger downstream signaling by itself. Recent studies have revealed that this protein modulates MDA5 filament formation, resulting in enhanced type I IFN production. Several other cytoplasmic RNA helicases are involved in RLR signaling. DDX3, DHX29, DHX36, and DDX60 RNA helicases have been reported to be involved in RLR-mediated type I IFN production after viral infection. However, the underlying mechanism is largely unknown. Future studies are required to reveal the role of RNA helicases in the RLR signaling pathway.

  4. T lymphocytes promote the antiviral and inflammatory responses of airway epithelial cells.

    Directory of Open Access Journals (Sweden)

    Lan Jornot

    Full Text Available HYPOTHESIS: T cells modulate the antiviral and inflammatory responses of airway epithelial cells to human rhinoviruses (HRV. METHODS: Differentiated primary human nasal epithelial cells (HNEC grown on collagen-coated filters were exposed apically to HRV14 for 6 h, washed thoroughly and co-cultured with anti-CD3/CD28 activated T cells added in the basolateral compartment for 40 h. RESULTS: HRV14 did not induce IFNγ, NOS2, CXCL8 and IL-6 in HNEC, but enhanced expression of the T cell attractant CXCL10. On the other hand, HNEC co-cultured with activated T cells produced CXCL10 at a level several orders of magnitude higher than that induced by HRV14. Albeit to a much lower degree, activated T cells also induced CXCL8, IL-6 and NOS2. Anti-IFNγ antibodies and TNF soluble receptor completely blocked CXCL10 upregulation. Furthermore, a significant correlation was observed between epithelial CXCL10 mRNA expression and the amounts of IFNγ and TNF secreted by T cells. Likewise, increasing numbers of T cells to a constant number of HNEC in co-cultures resulted in increasing epithelial CXCL10 production, attaining a plateau at high IFNγ and TNF levels. Hence, HNEC activation by T cells is induced mainly by IFNγ and/or TNF. Activated T cells also markedly inhibited viral replication in HNEC, partially through activation of the nitric oxide pathway. CONCLUSION: Cross-talk between T cells and HNEC results in activation of the latter and increases their contribution to airway inflammation and virus clearance.

  5. Secondary succession of arthropods and plants in the Arizona Sonoran Desert in response to transmission-line construction

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, C.D.; Beley, J.R.; Ditsworth, T.M.; Butt, S.M.

    1983-03-01

    At a site about 16 km south of Black Canyon City, Arizona, density of arthropods on an undisturbed plot after an access road was built for powerline construction was much greater than on a disturbed plot. Mites, springtails, leafhoppers, scale insects, ants and thrips were significantly reduced on the disturbed area. Diversity increased on the disturbed plot after construction, but density decreased. A slight increase in similarity (H', Clambda) of the arthropod communities of the two plots appears to be related to the modest increase in cover on the disturbed area. Globe-mallow, goosefoot and a four-o'clock were pioneer species and occurred only on the disturbed area. There was a significant reduction in cover of all plant species on the disturbed plot after construction, but there was a steady increase of annual forbs at the end of the study. The results indicate that restoration of numbers of arthropods on the disturbed area is dependent on the total plant cover on the plot, apparently regardless of the composition of the plant species involved. It is obvious in this area that the plant communities will remain dissimilar, with the pioneering herbaceous plants on the disturbed plot dominating. Construction of a powerline apparently has had little impact on the structure of the arthropod community on the disturbed area, as proportions of three trophic categories of arthropods have not been radically altered. The results of this study, when compared to other studies in the Sonoran Desert and in desert grasslands disturbed by powerline construction, indicate that lengthy secondary succession does occur in the Sonoran Desert. Early arthropod invaders were found to be mainly herbivores, with few parasites or predators, and an equilibrium was eventually reached between colonizers and space requirements. 35 references, 3 figures, 3 tables

  6. The innate immune response, clinical outcomes, and ex vivo HCV antiviral efficacy of a TLR7 agonist (PF-4878691).

    Science.gov (United States)

    Fidock, M D; Souberbielle, B E; Laxton, C; Rawal, J; Delpuech-Adams, O; Corey, T P; Colman, P; Kumar, V; Cheng, J B; Wright, K; Srinivasan, S; Rana, K; Craig, C; Horscroft, N; Perros, M; Westby, M; Webster, R; van der Ryst, E

    2011-06-01

    Hepatitis C virus (HCV) infection is an issue of global concern, and studies are ongoing to identify new therapies that are both effective and safe. PF-4878691 is a Toll-like receptor 7 (TLR7) agonist modeled so as to dissociate its antiviral activities from its inflammatory activities. In a proof-of-mechanism study in healthy volunteers who received doses of 3, 6, and 9 mg of PF-4878691 twice a week for 2 weeks, PF-4878691 induced biomarkers of the immune and interferon (IFN) responses in a dose-dependent and dose-frequency-related manner. A novel finding was induction of TLR7 expression in vivo in response to PF-4878691, leading to an amplified biomarker response. A nonresponder at the 9-mg dose had a polymorphism in the IFN-α receptor 1 subunit (Val168Leu). Two subjects who had received 9-mg doses experienced serious adverse events (SAEs), characterized by flu-like symptoms, hypotension, and lymphopenia, leading to early termination of the study. TLR7 stimulation results in a pharmacologic response at levels commensurate with predicted antiviral efficacy, but these doses are associated with SAEs, raising concerns about the therapeutic window of this class of compounds for the treatment of HCV infection. PMID:21451504

  7. UBXN1 Interferes with Rig-I-like Receptor-Mediated Antiviral Immune Response by Targeting MAVS

    Directory of Open Access Journals (Sweden)

    Penghua Wang

    2013-04-01

    Full Text Available RNA viruses are sensed by RIG-I-like receptors (RLRs, which signal through a mitochondria-associated adaptor molecule, MAVS, resulting in systemic antiviral immune responses. Although RLR signaling is essential for limiting RNA virus replication, it must be stringently controlled to prevent damage from inflammation. We demonstrate here that among all tested UBX-domain-containing protein family members, UBXN1 exhibits the strongest inhibitory effect on RNA-virus-induced type I interferon response. UBXN1 potently inhibits RLR- and MAVS-induced, but not TLR3-, TLR4-, or DNA-virus-induced innate immune responses. Depletion of UBXN1 enhances virus-induced innate immune responses, including those resulting from RNA viruses such as vesicular stomatitis, Sendai, West Nile, and dengue virus infection, repressing viral replication. Following viral infection, UBXN1 is induced, binds to MAVS, interferes with intracellular MAVS oligomerization, and disrupts the MAVS/TRAF3/TRAF6 signalosome. These findings underscore a critical role of UBXN1 in the modulation of a major antiviral signaling pathway.

  8. HCV RNA Activates APCs via TLR7/TLR8 While Virus Selectively Stimulates Macrophages Without Inducing Antiviral Responses

    Science.gov (United States)

    Zhang, Yuwei; El-Far, Mohamed; Dupuy, Franck P.; Abdel-Hakeem, Mohamed S.; He, Zhong; Procopio, Francesco Andrea; Shi, Yu; Haddad, Elias K.; Ancuta, Petronela; Sekaly, Rafick-Pierre; Said, Elias A.

    2016-01-01

    The innate and adaptive immune systems fail to control HCV infection in the majority of infected individuals. HCV is an ssRNA virus, which suggests a role for Toll-like receptors (TLRs) 7 and 8 in initiating the anti-viral response. Here we demonstrate that HCV genomic RNA harbours specific sequences that initiate an anti-HCV immune response through TLR7 and TLR8 in various antigen presenting cells. Conversely, HCV particles are detected by macrophages, but not by monocytes and DCs, through a TLR7/8 dependent mechanism; this leads to chloroquine sensitive production of pro-inflammatory cytokines including IL-1β, while the antiviral type I Interferon response is not triggered in these cells. Antibodies to DC-SIGN, a c-type lectin selectively expressed by macrophages but not pDCs or mDCs, block the production of cytokines. Novel anti-HCV vaccination strategies should target the induction of TLR7/8 stimulation in APCs in order to establish potent immune responses against HCV. PMID:27385120

  9. A functional C-terminal TRAF3-binding site in MAVS participates in positive and negative regulation of the IFN antiviral response

    Institute of Scientific and Technical Information of China (English)

    Suzanne Paz; Rongtuan Lin; John Hiscott; Myriam Vilasco; Steven J Werden; Meztli Arguello; Deshanthe Joseph-Pillai; Tiejun Zhao; Thi Lien-Anh Nguyen; Qiang Sun; Eliane F Meurs

    2011-01-01

    Recognition of viral RNA structures by the cytosolic sensor retinoic acid-inducible gene-Ⅰ (RIG-Ⅰ) results in the activation of signaling cascades that culminate with the generation of the type Ⅰ interferon (IFN) antiviral response. Onset of antiviral and inflammatory responses to viral pathogens necessitates the regulated spatiotemporal recruitment of signaling adapters,kinases and transcriptional proteins to the mitochondrial antiviral signaling protein (MAVS). We previously demonstrated that the serine/threonine kinase IKKε is recruited to the C-terminal region of MAVS following Sendal or vesicular stomatitis virus (VSV) infection,mediated by Lys63-linked polyubiquitination of MAVS at Lys500,resulting in inhibition of downstream IFN signaling (Paz et al,Mol Cell Biol,2009). In this study,we demonstrate that C-terminus of MAVS harbors a novel TRAF3-binding site in the aa450-468 region of MAVS. A consensus TRAF-interacting motif (TIM),455-PEENEY-460,within this site is required for TRAF3 binding and activation of IFN antiviral response genes,whereas mutation of the TIM eliminates TRAF3 binding and the downstream IFN response. Reconstitution of MAVS-/- mouse embryo fibroblasts with a construct expressing a TIM-mutated version of MAVS failed to restore the antiviral response or block VSV replication,whereas wild-type MAVS reconstituted antiviral inhibition of VSV replication. Furthermore,recruitment of IKKε to an adjacent C-terminal site (aa 468-540) in MAVS via Lys500 ubiquitination decreased TRAF3 binding and protein stability,thus contributing to IKKε-mediated shutdown of the IFN response. This study demonstrates that MAVS harbors a functional C-terminal TRAF3-binding site that participates in positive and negative regulation of the IFN antiviral response.

  10. Temperature-size responses match latitudinal-size clines in arthropods, revealing critical differences between aquatic and terrestrial species

    DEFF Research Database (Denmark)

    Horne, C.R.; Hirst, Andrew G.; Atkinson, D.

    2015-01-01

    of these gradients to date, and find that their direction and magnitude co-vary among 12 arthropod orders (r2 = 0.72). Body size in aquatic species generally reduces with both warming and decreasing latitude, whereas terrestrial species have much reduced and even opposite gradients. These patterns support...... the prediction that oxygen limitation is a major controlling factor in water, but not in air. Furthermore, voltinism explains much of the variation in T-S and L-S patterns in terrestrial but not aquatic species. While body size decreases with warming and with decreasing latitude in multivoltine terrestrial...... arthropods, size increases on average in univoltine species, consistent with predictions from size vs. season-length trade-offs...

  11. Effects of invasive plants on arthropods.

    Science.gov (United States)

    Litt, Andrea R; Cord, Erin E; Fulbright, Timothy E; Schuster, Greta L

    2014-12-01

    Non-native plants have invaded nearly all ecosystems and represent a major component of global ecological change. Plant invasions frequently change the composition and structure of vegetation communities, which can alter animal communities and ecosystem processes. We reviewed 87 articles published in the peer-reviewed literature to evaluate responses of arthropod communities and functional groups to non-native invasive plants. Total abundance of arthropods decreased in 62% of studies and increased in 15%. Taxonomic richness decreased in 48% of studies and increased in 13%. Herbivorous arthropods decreased in response to plant invasions in 48% of studies and increased in 17%, likely due to direct effects of decreased plant diversity. Predaceous arthropods decreased in response to invasive plants in 44% of studies, which may reflect indirect effects due to reductions in prey. Twenty-two percent of studies documented increases in predators, which may reflect changes in vegetation structure that improved mobility, survival, or web-building for these species. Detritivores increased in 67% of studies, likely in response to increased litter and decaying vegetation; no studies documented decreased abundance in this functional group. Although many researchers have examined effects of plant invasions on arthropods, sizeable information gaps remain, specifically regarding how invasive plants influence habitat and dietary requirements. Beyond this, the ability to predict changes in arthropod populations and communities associated with plant invasions could be improved by adopting a more functional and mechanistic approach. Understanding responses of arthropods to invasive plants will critically inform conservation of virtually all biodiversity and ecological processes because so many organisms depend on arthropods as prey or for their functional roles, including pollination, seed dispersal, and decomposition. Given their short generation times and ability to respond rapidly to

  12. Budesonide and formoterol reduce early innate anti-viral immune responses in vitro.

    Directory of Open Access Journals (Sweden)

    Janet M Davies

    Full Text Available Asthma is a chronic inflammatory airways disease in which respiratory viral infections frequently trigger exacerbations. Current treatment of asthma with combinations of inhaled corticosteroids and long acting beta2 agonists improves asthma control and reduces exacerbations but what impact this might have on innate anti-viral immunity is unclear. We investigated the in vitro effects of asthma drugs on innate anti-viral immunity. Peripheral blood mononuclear cells (PBMC from healthy and asthmatic donors were cultured for 24 hours with the Toll-like receptor 7 agonist, imiquimod, or rhinovirus 16 (RV16 in the presence of budesonide and/or formoterol. Production of proinflammatory cytokines and expression of anti-viral intracellular signalling molecules were measured by ELISA and RT-PCR respectively. In PBMC from healthy donors, budesonide alone inhibited IP-10 and IL-6 production induced by imiquimod in a concentration-dependent manner and the degree of inhibition was amplified when budesonide and formoterol were used in combination. Formoterol alone had little effect on these parameters, except at high concentrations (10⁻⁶ M when IL-6 production increased. In RV16 stimulated PBMC, the combination of budesonide and formoterol inhibited IFNα and IP-10 production in asthmatic as well as healthy donors. Combination of budesonide and formoterol also inhibited RV16-stimulated expression of the type I IFN induced genes myxovirus protein A and 2', 5' oligoadenylate synthetise. Notably, RV16 stimulated lower levels of type Myxovirus A and oligoadenylate synthase in PBMC of asthmatics than control donors. These in vitro studies demonstrate that combinations of drugs commonly used in asthma therapy inhibit both early pro-inflammatory cytokines and key aspects of the type I IFN pathway. These findings suggest that budesonide and formoterol curtail excessive inflammation induced by rhinovirus infections in patients with asthma, but whether this inhibits

  13. Chronic GvHD decreases antiviral immune responses in allogeneic BMT

    OpenAIRE

    Hossain, Mohammad S.; Roback, John D.; Pollack, Brian P.; Jaye, David L.; Langston, Amelia; Waller, Edmund K.

    2007-01-01

    Chronic graft-versus-host disease (cGvHD) is associated with functional immunodeficiency and an increased risk of opportunistic infections in allogeneic bone marrow transplantation (BMT). We used a parent to F1 model of allogeneic BMT to test the hypothesis that cGvHD leads to impaired antigen-specific antiviral immunity and compared BM transplant recipients with cGvHD to control groups of allogeneic BM transplant recipients without GvHD. Mice with and without cGvHD received a nonlethal dose ...

  14. IFNβ/TNFα synergism induces a non-canonical STAT2/IRF9-dependent pathway triggering a novel DUOX2 NADPH Oxidase-mediated airway antiviral response

    Institute of Scientific and Technical Information of China (English)

    Karin Fink; Lydie Martin; Esperance Mukawera; Stéfany Chartier; Xavier De Deken; Emmanuelle Brochiero; Fran(c)oise Miot

    2013-01-01

    Airway epithelial cells are key initial innate immune responders in the fight against respiratory viruses,primarily via the secretion of antiviral and proinflammatory cytokines that act in an autocrine/paracrine fashion to trigger the establishment of an antiviral state.It is currently thought that the early antiviral state in airway epithelial cells primarily relies on IFNβ secretion and the subsequent activation of the interferon-stimulated gene factor 3 (ISGF3) transcription factor complex,composed of STAT1,STAT2 and IRF9,which regulates the expression of a panoply of interferon-stimulated genes encoding proteins with antiviral activities.However,the specific pathways engaged by the synergistic action of different cytokines during viral infections,and the resulting physiological outcomes are still ill-defined.Here,we unveil a novel delayed antiviral response in the airways,which is initiated by the synergistic autocrine/paracrine action of IFNβ and TNFα,and signals through a non-canonical STAT2-and IRF9-dependent,but STAT1-independent cascade.This pathway ultimately leads to the late induction of the DUOX2 NADPH oxidase expression.Importantly,our study uncovers that the development of the antiviral state relies on DUOX2-dependent H2O2 production.Key antiviral pathways are often targeted by evasion strategies evolved by various pathogenic viruses.In this regard,the importance of the novel DUOX2-dependent antiviral pathway is further underlined by the observation that the human respiratory syncytial virus is able to subvert DUOX2 induction.

  15. Gene Expression and Antiviral Activity of Interleukin-35 in Response to Influenza A Virus Infection.

    Science.gov (United States)

    Wang, Li; Zhu, Shengli; Xu, Gang; Feng, Jian; Han, Tao; Zhao, Fanpeng; She, Ying-Long; Liu, Shi; Ye, Linbai; Zhu, Ying

    2016-08-01

    Interleukin-35 (IL-35) is a newly described member of the IL-12 family. It has been reported to inhibit inflammation and autoimmune inflammatory disease and can increase apoptotic sensitivity. Little is known about the role of IL-35 during viral infection. Herein, high levels of IL-35 were found in peripheral blood mononuclear cells and throat swabs from patients with seasonal influenza A virus (IAV) relative to healthy individuals. IAV infection of human lung epithelial and primary cells increased levels of IL-35 mRNA and protein. Further studies demonstrated that IAV-induced IL-35 transcription is regulated by NF-κB. IL-35 expression was significantly suppressed by selective inhibitors of cyclooxygenase-2 (COX-2) and inducible nitric-oxide synthase, indicating their involvement in IL-35 expression. Interestingly, IL-35 production may have suppressed IAV RNA replication and viral protein synthesis via induction of type I and III interferons (IFN), leading to activation of downstream IFN effectors, including double-stranded RNA-dependent protein kinase, 2',5'-oligoadenylate synthetase, and myxovirus resistance protein. IL-35 exhibited extensive antiviral activity against the hepatitis B virus, enterovirus 71, and vesicular stomatitis virus. Our results demonstrate that IL-35 is a novel IAV-inducible cytokine, and its production elicits antiviral activity. PMID:27307042

  16. Tomato spotted wilt virus benefits a non-vector arthropod, Tetranychus urticae, by modulating different plant responses in tomato.

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    Punya Nachappa

    Full Text Available The interaction between plant viruses and non-vector arthropod herbivores is poorly understood. However, there is accumulating evidence that plant viruses can impact fitness of non-vector herbivores. In this study, we used oligonucleotide microarrays, phytohormone, and total free amino acid analyses to characterize the molecular mechanisms underlying the interaction between Tomato spotted wilt virus (TSWV and a non-vector arthropod, twospotted spider mite (Tetranychusurticae, on tomato plants, Solanumlycopersicum. Twospotted spider mites showed increased preference for and fecundity on TSWV-infected plants compared to mock-inoculated plants. Transcriptome profiles of TSWV-infected plants indicated significant up-regulation of salicylic acid (SA-related genes, but no apparent down-regulation of jasmonic acid (JA-related genes which could potentially confer induced resistance against TSM. This suggests that there was no antagonistic crosstalk between the signaling pathways to influence the interaction between TSWV and spider mites. In fact, SA- and JA-related genes were up-regulated when plants were challenged with both TSWV and the herbivore. TSWV infection resulted in down-regulation of cell wall-related genes and photosynthesis-associated genes, which may contribute to host plant susceptibility. There was a three-fold increase in total free amino acid content in virus-infected plants compared to mock-inoculated plants. Total free amino acid content is critical for arthropod nutrition and may, in part, explain the apparent positive indirect effect of TSWV on spider mites. Taken together, these data suggest that the mechanism(s of increased host suitability of TSWV-infected plants to non-vector herbivores is complex and likely involves several plant biochemical processes.

  17. Plasmacytoid Dendritic Cells Act as the Most Competent Cell Type in Linking Antiviral Innate and Adaptive Immune Responses

    Institute of Scientific and Technical Information of China (English)

    Zheng Zhang; Fu-Sheng Wang

    2005-01-01

    Appropriate in vivo control of plasmacytoid dendritic cell (pDC) recruitment and activation is a fundamental requirement for defense against viral infection. During this process, a pivotal event that influences the outcome of viral infection is the production of high levels of type I interferon by pDCs. In particular, recent research findings showed that pDCs not only shape the nature of innate resistance, but are also responsible for the successful transition from innate to adaptive immunity for viral resistance. In addition, pDCs can differentiate into antigen presenting cells that may regulate tolerance to a given pathogen. Importantly, in a series of recent clinical studies,pDCs appeared to be defective in number and function in conditions of chronic viral diseases such as infected with HIV-1, HBV or HCV. pDC-associated clinical antiviral therapy is also emerging. This review describes research findings exanining the functional and antiviral properties of in vivo pDC plasticity.

  18. Elevation of intact and proteolytic fragments of acute phase proteins constitutes the earliest systemic antiviral response in HIV-1 infection.

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    Holger B Kramer

    2010-05-01

    Full Text Available The earliest immune responses activated in acute human immunodeficiency virus type 1 infection (AHI exert a critical influence on subsequent virus spread or containment. During this time frame, components of the innate immune system such as macrophages and DCs, NK cells, beta-defensins, complement and other anti-microbial factors, which have all been implicated in modulating HIV infection, may play particularly important roles. A proteomics-based screen was performed on a cohort from whom samples were available at time points prior to the earliest positive HIV detection. The ability of selected factors found to be elevated in the plasma during AHI to inhibit HIV-1 replication was analyzed using in vitro PBMC and DC infection models. Analysis of unique plasma donor panels spanning the eclipse and viral expansion phases revealed very early alterations in plasma proteins in AHI. Induction of acute phase protein serum amyloid A (A-SAA occurred as early as 5-7 days prior to the first detection of plasma viral RNA, considerably prior to any elevation in systemic cytokine levels. Furthermore, a proteolytic fragment of alpha-1-antitrypsin (AAT, termed virus inhibitory peptide (VIRIP, was observed in plasma coincident with viremia. Both A-SAA and VIRIP have anti-viral activity in vitro and quantitation of their plasma levels indicated that circulating concentrations are likely to be within the range of their inhibitory activity. Our results provide evidence for a first wave of host anti-viral defense occurring in the eclipse phase of AHI prior to systemic activation of other immune responses. Insights gained into the mechanism of action of acute-phase reactants and other innate molecules against HIV and how they are induced could be exploited for the future development of more efficient prophylactic vaccine strategies.

  19. Antiviral Type I and Type III Interferon Responses in the Central Nervous System

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    Thomas Michiels

    2013-03-01

    Full Text Available The central nervous system (CNS harbors highly differentiated cells, such as neurons that are essential to coordinate the functions of complex organisms. This organ is partly protected by the blood-brain barrier (BBB from toxic substances and pathogens carried in the bloodstream. Yet, neurotropic viruses can reach the CNS either by crossing the BBB after viremia, or by exploiting motile infected cells as Trojan horses, or by using axonal transport. Type I and type III interferons (IFNs are cytokines that are critical to control early steps of viral infections. Deficiencies in the IFN pathway have been associated with fatal viral encephalitis both in humans and mice. Therefore, the IFN system provides an essential protection of the CNS against viral infections. Yet, basal activity of the IFN system appears to be low within the CNS, likely owing to the toxicity of IFN to this organ. Moreover, after viral infection, neurons and oligodendrocytes were reported to be relatively poor IFN producers and appear to keep some susceptibility to neurotropic viruses, even in the presence of IFN. This review addresses some trends and recent developments concerning the role of type I and type III IFNs in: i preventing neuroinvasion and infection of CNS cells; ii the identity of IFN-producing cells in the CNS; iii the antiviral activity of ISGs; and iv the activity of viral proteins of neurotropic viruses that target the IFN pathway.

  20. Alpha interferon-induced antiviral response noncytolytically reduces replication defective adenovirus DNA in MDBK cells.

    Science.gov (United States)

    Guo, Ju-Tao; Zhou, Tianlun; Guo, Haitao; Block, Timothy M

    2007-12-01

    Although alpha interferon (IFN-alpha) is of benefit in the treatment of viral hepatitis B, HBV replication has been refractory to the cytokine in commonly used hepatocyte-derived cell lines. In search for a cell culture system to study the mechanism by which IFN-alpha inhibits HBV replication, we infected a variety of cell lines with an adenoviral vector containing a replication competent 1.3-fold genome length HBV DNA (AdHBV) and followed by incubation with IFN-alpha. We found that IFN-alpha efficiently decreased the level of HBV DNA replicative intermediates in AdHBV infected Madin-Darby bovine kidney (MDBK) cells. Further analysis revealed, surprisingly, that IFN-alpha did not directly inhibit HBV replication, rather the amount of adenovirus DNA in the nuclei of MDBK cells was reduced. As a consequence, HBV RNA transcription and DNA replication were inhibited. Experiments with adenoviral vector expressing a green fluorescent protein (GFP) further supported the notion that IFN-alpha treatment noncytolytically eliminated adenovirus DNA, but did not kill the vector infected MDBK cells. Our data suggest that IFN-alpha-induced antiviral program is able to discriminate host cellular DNA from episomal viral DNA and might represent a novel pathway of interferon mediate innate defense against DNA virus infections.

  1. Cell adhesion molecules and hyaluronic acid as markers of inflammation, fibrosis and response to antiviral therapy in chronic hepatitis C patients

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    Esther Granot

    2001-01-01

    Full Text Available Objective: Cell adhesion molecules (intracellular adhesion molecule-1 (ICAM-1, vascular cell adhesion molecule-1 (VCAM-1 and hyaluronic acid, markers of inflammation and fibrosis were monitored in hepatitis C patients to determine whether changes in plasma levels, during antiviral treatment, can predict long-term response to therapy.

  2. Depletion of elongation initiation factor 4E binding proteins by CRISPR/Cas9 genome editing enhances antiviral response in porcine cells

    Science.gov (United States)

    Type I interferons (IFN) are key mediators of the innate antiviral response in mammalian cells. Elongation initiation factor 4E binding proteins (4E-BPs) are translational controllers of interferon regulatory factor 7 (IRF7), the master regulator of IFN transcription. The role of 4EBPs in the negat...

  3. Depletion of elongation initiation factor 4E binding proteins by CRISPR/Cas9 enhances the antiviral response in porcine cells.

    Science.gov (United States)

    Ramírez-Carvajal, Lisbeth; Singh, Neetu; de los Santos, Teresa; Rodríguez, Luis L; Long, Charles R

    2016-01-01

    Type I interferons (IFNs) are key mediators of the innate antiviral response in mammalian cells. Elongation initiation factor 4E binding proteins (4E-BPs) are translational controllers of interferon regulatory factor 7 (IRF-7), the "master regulator" of IFN transcription. Previous studies have suggested that mouse cells depleted of 4E-BPs are more sensitive to IFNβ treatment and had lower viral loads as compared to wild type (WT) cells. However, such approach has not been tested as an antiviral strategy in livestock species. In this study, we tested the antiviral activity of porcine cells depleted of 4E-BP1 by a Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)/CRISPR-associated protein-9 nuclease (Cas9) genome engineering system. We found that 4E-BP1 knockout (KO) porcine cells had increased expression of IFNα and β, IFN stimulated genes, and significant reduction in vesicular stomatitis virus titer as compare to WT cells. No phenotypical changes associated with CRISPR/Cas9 manipulation were observed in 4E-BP1 KO cells. This work highlights the use of the CRISPR/Cas9 system to enhance the antiviral response in porcine cells.

  4. Influenza A(H1N1pdm09 virus suppresses RIG-I initiated innate antiviral responses in the human lung.

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    Wenxin Wu

    Full Text Available Influenza infection is a major cause of morbidity and mortality. Retinoic acid-inducible gene I (RIG-I is believed to play an important role in the recognition of, and response to, influenza virus and other RNA viruses. Our study focuses on the hypothesis that pandemic H1N1/09 influenza virus alters the influenza-induced proinflammatory response and suppresses host antiviral activity. We first compared the innate response to a clinical isolate of influenza A(H1N1pdm09 virus, OK/09, a clinical isolate of seasonal H3N2 virus, OK/06, and to a laboratory adapted seasonal H1N1 virus, PR8, using a unique human lung organ culture model. Exposure of human lung tissue to either pandemic or seasonal influenza virus resulted in infection and replication in alveolar epithelial cells. Pandemic virus induces a diminished RIG-I mRNA and antiviral cytokine response than seasonal virus in human lung. The suppression of antiviral response and RIG-I mRNA expression was confirmed at the protein level by ELISA and western blot. We performed a time course of RIG-I and interferon-β (IFN-β mRNA induction by the two viruses. RIG-I and IFN-β induction by OK/09 was of lower amplitude and shorter duration than that caused by PR8. In contrast, the pandemic virus OK/09 caused similar induction of proinflammatory cytokines, IL-8 and IL-6, at both the transcriptional and translational level as PR8 in human lung. Differential antiviral responses did not appear to be due to a difference in cellular infectivity as immunohistochemistry showed that both viruses infected alveolar macrophages and epithelial cells. These findings show that influenza A(H1N1pdm09 virus suppresses anti-viral immune responses in infected human lung through inhibition of viral-mediated induction of the pattern recognition receptor, RIG-I, though proinflammatory cytokine induction was unaltered. This immunosuppression of the host antiviral response by pandemic virus may have contributed to the more

  5. Antibody-Dependent Enhancement of Dengue Virus Infection in Primary Human Macrophages; Balancing Higher Fusion against Antiviral Responses.

    Science.gov (United States)

    Flipse, Jacky; Diosa-Toro, Mayra A; Hoornweg, Tabitha E; van de Pol, Denise P I; Urcuqui-Inchima, Silvio; Smit, Jolanda M

    2016-01-01

    The dogma is that the human immune system protects us against pathogens. Yet, several viruses, like dengue virus, antagonize the hosts' antibodies to enhance their viral load and disease severity; a phenomenon called antibody-dependent enhancement of infection. This study offers novel insights in the molecular mechanism of antibody-mediated enhancement (ADE) of dengue virus infection in primary human macrophages. No differences were observed in the number of bound and internalized DENV particles following infection in the absence and presence of enhancing concentrations of antibodies. Yet, we did find an increase in membrane fusion activity during ADE of DENV infection. The higher fusion activity is coupled to a low antiviral response early in infection and subsequently a higher infection efficiency. Apparently, subtle enhancements early in the viral life cycle cascades into strong effects on infection, virus production and immune response. Importantly, and in contrast to other studies, the antibody-opsonized virus particles do not trigger immune suppression and remain sensitive to interferon. Additionally, this study gives insight in how human macrophages interact and respond to viral infections and the tight regulation thereof under various conditions of infection. PMID:27380892

  6. Antibody-Dependent Enhancement of Dengue Virus Infection in Primary Human Macrophages; Balancing Higher Fusion against Antiviral Responses

    Science.gov (United States)

    Flipse, Jacky; Diosa-Toro, Mayra A.; Hoornweg, Tabitha E.; van de Pol, Denise P. I.; Urcuqui-Inchima, Silvio; Smit, Jolanda M.

    2016-01-01

    The dogma is that the human immune system protects us against pathogens. Yet, several viruses, like dengue virus, antagonize the hosts’ antibodies to enhance their viral load and disease severity; a phenomenon called antibody-dependent enhancement of infection. This study offers novel insights in the molecular mechanism of antibody-mediated enhancement (ADE) of dengue virus infection in primary human macrophages. No differences were observed in the number of bound and internalized DENV particles following infection in the absence and presence of enhancing concentrations of antibodies. Yet, we did find an increase in membrane fusion activity during ADE of DENV infection. The higher fusion activity is coupled to a low antiviral response early in infection and subsequently a higher infection efficiency. Apparently, subtle enhancements early in the viral life cycle cascades into strong effects on infection, virus production and immune response. Importantly, and in contrast to other studies, the antibody-opsonized virus particles do not trigger immune suppression and remain sensitive to interferon. Additionally, this study gives insight in how human macrophages interact and respond to viral infections and the tight regulation thereof under various conditions of infection. PMID:27380892

  7. ERK signaling couples nutrient status to antiviral defense in the insect gut.

    Science.gov (United States)

    Xu, Jie; Hopkins, Kaycie; Sabin, Leah; Yasunaga, Ari; Subramanian, Harry; Lamborn, Ian; Gordesky-Gold, Beth; Cherry, Sara

    2013-09-10

    A unique facet of arthropod-borne virus (arbovirus) infection is that the pathogens are orally acquired by an insect vector during the taking of a blood meal, which directly links nutrient acquisition and pathogen challenge. We show that the nutrient responsive ERK pathway is both induced by and restricts disparate arboviruses in Drosophila intestines, providing insight into the molecular determinants of the antiviral "midgut barrier." Wild-type flies are refractory to oral infection by arboviruses, including Sindbis virus and vesicular stomatitis virus, but this innate restriction can be overcome chemically by oral administration of an ERK pathway inhibitor or genetically via the specific loss of ERK in Drosophila intestinal epithelial cells. In addition, we found that vertebrate insulin, which activates ERK in the mosquito gut during a blood meal, restricts viral infection in Drosophila cells and against viral invasion of the insect gut epithelium. We find that ERK's antiviral signaling activity is likely conserved in Aedes mosquitoes, because genetic or pharmacologic manipulation of the ERK pathway affects viral infection of mosquito cells. These studies demonstrate that ERK signaling has a broadly antiviral role in insects and suggest that insects take advantage of cross-species signals in the meal to trigger antiviral immunity.

  8. Antibody-independent control of gamma-herpesvirus latency via B cell induction of anti-viral T cell responses.

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    Kelly B McClellan

    2006-06-01

    Full Text Available B cells can use antibody-dependent mechanisms to control latent viral infections. It is unknown whether this represents the sole function of B cells during chronic viral infection. We report here that hen egg lysozyme (HEL-specific B cells can contribute to the control of murine gamma-herpesvirus 68 (gammaHV68 latency without producing anti-viral antibody. HEL-specific B cells normalized defects in T cell numbers and proliferation observed in B cell-/- mice during the early phase of gammaHV68 latency. HEL-specific B cells also reversed defects in CD8 and CD4 T cell cytokine production observed in B cell-/- mice, generating CD8 and CD4 T cells necessary for control of latency. Furthermore, HEL-specific B cells were able to present virally encoded antigen to CD8 T cells. Therefore, B cells have antibody independent functions, including antigen presentation, that are important for control of gamma-herpesvirus latency. Exploitation of this property of B cells may allow enhanced vaccine responses to chronic virus infection.

  9. A specific CpG oligodeoxynucleotide induces protective antiviral responses against grass carp reovirus in grass carp Ctenopharyngodon idella.

    Science.gov (United States)

    Su, Hang; Yuan, Gailing; Su, Jianguo

    2016-07-01

    CpG oligodeoxynucleotides (ODNs) show strong immune stimulatory activity in vertebrate, however, they possess specific sequence feature among species. In this study, we screened out an optimal CpG ODN sequence for grass carp (Ctenopharyngodon idella), 1670A 5'-TCGAACGTTTTAACGTTTTAACGTT-3', from six published sequences and three sequences designed by authors based on grass carp head kidney mononuclear cells and CIK (C. idella kidney) cells proliferation. VP4 mRNA expression was strongly inhibited by CpG ODN 1670A in CIK cells with GCRV infection, showing its strong antiviral activity. The mechanism via toll-like receptor 9 (TLR9)-mediated signaling pathway was measured by real-time quantitative RT-PCR, and TLR21 did not play a role in the immune response to CpG ODN. The late up-regulation of CiRIG-I mRNA expression indicated that RIG-I-like receptors (RLRs) signaling pathway participated in the immune response to CpG ODN which is the first report on the interaction between CpG and RLRs. We also found that the efficient CpG ODN can activates interferon system. Infected with GCRV, type I interferon expression was reduced and type II interferon was induced by the efficient CpG ODN in CIK cells, especially IFNγ2, suggesting that IFNγ2 played an important role in response to the efficient CpG ODN. These results provide a theoretical basis and new development trend for further research on CpG and the application of CpG vaccine adjuvant in grass carp disease control. PMID:26972738

  10. Antiviral Therapy for Chronic HCV Infection: Virological Response and Long-Term Outcome

    NARCIS (Netherlands)

    A.J.P. van der Meer (Adriaan)

    2014-01-01

    markdownabstract__Abstract__ Hepatitis C is a major global health problem which is responsible for over 350,000 deaths each year.1 In total, there are thought to be around 150 million hepatitis C virus (HCV) carriers, which comprise about 3% of the world population. The prevalence of HCV infection,

  11. ORF7-encoded accessory protein 7a of feline infectious peritonitis virus as a counteragent against IFN-α-induced antiviral response.

    Science.gov (United States)

    Dedeurwaerder, Annelike; Olyslaegers, Dominique A J; Desmarets, Lowiese M B; Roukaerts, Inge D M; Theuns, Sebastiaan; Nauwynck, Hans J

    2014-02-01

    The type I IFN-mediated immune response is the first line of antiviral defence. Coronaviruses, like many other viruses, have evolved mechanisms to evade this innate response, ensuring their survival. Several coronavirus accessory genes play a central role in these pathways, but for feline coronaviruses this has never to our knowledge been studied. As it has been demonstrated previously that ORF7 is essential for efficient replication in vitro and virulence in vivo of feline infectious peritonitis virus (FIPV), the role of this ORF in the evasion of the IFN-α antiviral response was investigated. Deletion of ORF7 from FIPV strain 79-1146 (FIPV-Δ7) rendered the virus more susceptible to IFN-α treatment. Given that ORF7 encodes two proteins, 7a and 7b, it was further explored which of these proteins is active in this mechanism. Providing 7a protein in trans rescued the mutant FIPV-Δ7 from IFN sensitivity, which was not achieved by addition of 7b protein. Nevertheless, addition of protein 7a to FIPV-Δ3Δ7, a FIPV mutant deleted in both ORF3 and ORF7, could no longer increase the replication capacity of this mutant in the presence of IFN. These results indicate that FIPV 7a protein is a type I IFN antagonist and protects the virus from the antiviral state induced by IFN, but it needs the presence of ORF3-encoded proteins to exert its antagonistic function.

  12. Predictors of response to antiviral therapy in patients with chronic hepatitis C from Pakistani population

    Institute of Scientific and Technical Information of China (English)

    Hafsa Aziz; Muhammad Amin Athar; Shahnaz Murtaza; Javaid Irfan; Yasir Waheed; Iram Bilal; Abida Raza

    2011-01-01

    Background Hepatitis C virus (HCV) constitutes a major public health issue around the world, especially in developing countries like Pakistan. In this study, we assessed outcome of interferon (INF) treatment in chronic hepatitis C patients categorized by gender, age, and viral load.Methods In this study, 750 HCV positive patients with genotype 3 were selected, out of which 616 completed the entire treatment. Their personal history, pro-treatment HCV RNA and serum alanine transaminase (ALT) was quantified.Patients were treated with combination therapy of INF-α 2b three million units (thrice a week) plus ribavirin (1000-1200mg per day) for 24 weeks. After 24 weeks their HCV RNA and serum ALT level was quantified.Results Out of the 616 patients, 391 (63.5%) responded to therapeutic regimen (INF-α 2b plus ribavirin). Among the responders, 27.1% were men and 36.4% were women. Best treatment response was observed in patients having Iow viral load <8×105 IU/ml and age ≤40 years than patients having Iow viral load and age >40 years (73.2% vs. 60.3%, P=0.05).Conclusions Better response to IFN-α 2b plus ribavirin was observed in patients with lower viral RNA and younger age.It suggests that all patients considered for treatment should have quantification of serum HCV RNA level. The result can be used to counsel patients on the likelihood of response and may influence the patient's decision on treatment.

  13. Insulin resistance and response to antiviral therapy in chronic hepatitis C: mechanisms and management.

    Science.gov (United States)

    del Campo, José A; López, Reyes Aparcero; Romero-Gómez, Manuel

    2010-01-01

    Insulin resistance has been found to be an independent factor predicting sustained response to peginterferon plus ribavirin in patients with chronic hepatitis C. Insulin resistance seems to be involved in decreased sensitivity to interferon and could block interferon intracellular signaling. Insulin resistance promotes steatosis and fibrosis progression, induces pro-inflammatory cytokine secretion and increases adipose tissue, decreasing interferon availability. Moreover, suppressor of cytokines 3 and protein tyrosine-phosphatase seems to be able to block interferon and insulin signaling, building a feed-forward loop. Insulin resistance can be treated with exercise, diet or through the use of drugs that improve insulin sensitivity, like biguanides or glitazones. A recent controlled, randomized, double-blind clinical trial (TRIC-1) examined the effect of adding metformin to standard therapy in the treatment of hepatitis C. This study demonstrated that women infected with hepatitis C virus genotype 1 and HOMA >2 treated with metformin showed a greater drop in viral load during the first 12 weeks and a doubled sustained viral response in comparison with females receiving placebo. Pioglitazone has been used in previous nonresponders and naïve patients with disappointing results in two pilot trials. The mechanisms by which the virus promotes insulin resistance seems to be genotype-dependent and could explain, at least in part, the discrepancies between insulin sensitizers. Insulin resistance is a new target in the challenging management of chronic hepatitis C. PMID:20460925

  14. Enemy at the gates: forward genetics of the mouse antiviral response.

    Science.gov (United States)

    Kielczewska, Agnieszka; Vidal, Silvia M

    2006-10-01

    The environment and the genetic constitution of both the pathogen and the host influence the severity and the outcome of viral infections. Whereas identification of the host component in humans remains challenging, recent progress in defining genes through analysis of mouse models of infection presenting natural or chemically induced variation in host susceptibility mark a fruitful period of gene discovery. This includes recognition that UNC93B1, which encodes an endocytic protein, is a susceptibility gene, providing an unexpected entry point to our understanding of the response against herpesvirus infection. By contrast, elucidation of alternative mechanisms of host resistance against mouse cytomegalovirus in inbred mouse strains has led to new insights regarding molecular recognition of the infected cells by natural killer cell MHC class I receptors. In addition, the conservation of genetic and functional aspects between mouse and human is enabling a rational pursuit of potential cures. With the continuous development of resources for experimental investigation of the genome, the production of new mutant alleles, and the phenotypic characterization of new models of infection, we predict that mouse genetic models will make an increasing contribution to our understanding of the genetic puzzle of host response to virus infection. PMID:16879955

  15. Anti-diabetic drugs, insulin and metformin, have no direct interaction with hepatitis C virus infection or anti-viral interferon response

    Directory of Open Access Journals (Sweden)

    Mohamad S. Hakim

    2014-01-01

    Full Text Available Hepatitis C virus (HCV infection is associated with insulin resistance (IR and type 2 diabetes (T2D. Chronic HCV patients with IR and T2D appear to have a decreased response to the standard pegylated-interferon-alpha and ribavirin (PEG-IFN/RBV anti-viral therapy. Insulin and metformin are anti-diabetic drugs regularly used in the clinic. A previous in vitro study has shown a negative effect of insulin on interferon signaling. In the clinic, adding metformin to PEG-IFN/RBV therapy was reported to increase the response rate in chronic HCV patients and it has been suggested this effect derives from an improved anti-viral action of interferon. The goal of this study was to further investigate the molecular insight of insulin and metformin interaction with HCV infection and the anti-viral action of interferon. We used two cell culture models of HCV infection. One is a sub-genomic model that assays viral replication through luciferase reporter gene expression. The other one is a full-length infectious model derived from the JFH1 genotype 2a isolate. We found that both insulin and metformin do not affect HCV infection. Insulin and metformin also do not influence the anti-viral potency of interferon. In addition, there is no direct interaction between these two drugs and interferon signaling. Our results do not confirm the previous laboratory observation that insulin interferes with interferon signaling and suggest that classical nutritional signaling through mTOR may be not involved in HCV replication. If metformin indeed can increase the response rate to interferon therapy in patients, our data indicate that this could be mediated via an indirect mechanisms.

  16. Simulation of arthropod abundance from plant composition

    Directory of Open Access Journals (Sweden)

    WenJun Zhang

    2011-04-01

    Full Text Available The relationship between arthropod abundance and plant composition is extremely complex. It is very hard to develop a mechanistic model to describe the relationship. This study aimed to simulate arthropod abundance from plant composition on grassland using an artificial neural network developed by the author, and to compare simulation performances between the neural network and conventional models. The results revealed that there were complex interactions between plants and arthropods, and the arthropod abundance on grassland was significantly determined of plant families and their cover-degrees rather than plant species and their cover-degrees. Neural network exhibited a better simulation performance than multivariate regression and response surface model. Cross validation indicated that prediction performance of neural network was also superior to these models. It was concluded that neural network is an effective tool to model arthropod abundance from plant composition on grassland. A moderate dimensionality for input space may be determined to produce a reasonably trained neural network. Such procedures for dimensionality reduction as PCE, etc., were suggested being used in the data treatment in neural network modeling. A high dimensionality for input space and a few samples in the input set would result in the deficient learning of neural network. Randomization procedure for sample submission would help to eliminate the sequence correlation but may result in a worse performance in simulation and prediction. It was suggested that randomization procedure could be used to the sample submission for these situations with a lot of samples and a lower dimensionality.

  17. Transcriptome profiling of the antiviral immune response in Atlantic cod macrophages.

    Science.gov (United States)

    Eslamloo, Khalil; Xue, Xi; Booman, Marije; Smith, Nicole C; Rise, Matthew L

    2016-10-01

    A study was conducted to determine the transcriptome response of Atlantic cod (Gadus morhua) macrophages to the viral mimic, polyriboinosinic polyribocytidylic acid (pIC), using a 20K Atlantic cod microarray platform and qPCR. We identified 285 significantly up-regulated and 161 significantly down-regulated probes in cod macrophages 24 h after pIC stimulation. A subset of 26 microarray-identified transcripts was subjected to qPCR validation using samples treated with pIC or phosphate-buffered saline (control) over time (3, 6, 12, 24, 48 h), and 77% of them showed a significant response to pIC. The microarray and qPCR analyses in this study showed that pIC induced the expression of cod macrophage transcripts involved in RLR- and TLR-dependent pathogen recognition (e.g. tlr3, tlr7, mda5 and lgp2), as well as signal transducers (e.g. stat1 and nfkbia) and transcription activators (e.g. irf7 and irf10) in the MyD88-independent and dependent signalling pathways. Several immune effectors (e.g. isg15s, viperin, herc4, mip2 and ccl13) were significantly up-regulated in pIC-stimulated cod macrophages. The expression of some transcripts (e.g. irf7, irf10, viperin) was significantly up-regulated by pIC as early as 12 h. All pIC-induced transcripts had peak expression at either 24 h (e.g. tlr7, irf7, mip2) or 48 h (e.g. tlr3, lgp2, stat1). This study suggests possible roles of both vertebrate-conserved (e.g. tlr3 as an up-regulated gene) and fish-specific (tlr22g as a down-regulated gene) receptors in dsRNA recognition, and the importance of conserved and potentially fish-specific interferon stimulated genes in cod macrophages. PMID:27255218

  18. Lack of antiviral antibody response in koalas infected with koala retroviruses (KoRV).

    Science.gov (United States)

    Fiebig, Uwe; Keller, Martina; Möller, Annekatrin; Timms, Peter; Denner, Joachim

    2015-02-16

    Many wild koalas are infected with the koala retrovirus, KoRV, some of which suffer from lymphoma and chlamydial disease. Three subgroups, KoRV-A, KoRV-B and KoRV-J, have so far been described. It is well known that other closely related gammaretroviruses can induce tumours and severe immunodeficiencies in their respective hosts and a possible role for KoRV infection in lymphoma and chlamydial disease in koalas has been suggested. In many wild koalas, KoRV-A has become endogenised, i.e., it is integrated in the germ-line and is passed on with normal cellular genes. In this study, sera from koalas in European zoos and from wild animals in Australia were screened for antibodies against KoRV-A. These naturally infected animals all carry endogenous KoRV-A and two zoo animals are also infected with KoRV-B. The antibody response is generally an important diagnostic tool for detecting retrovirus infections. However, when Western blot analyses were performed using purified virus or recombinant proteins corresponding to KoRV-A, none of the koalas tested positive for specific antibodies, suggesting a state of tolerance. These results have implications for koala vaccination, as they suggest that therapeutic immunisation of animals carrying and expressing endogenous KoRV-A will not be successful. However, it remains unclear whether these animals can be immunised against KoRV-B and immunisation of uninfected koalas could still be worthwhile.

  19. Limitations in dose-response and surrogate species methodologies for risk assessment of Cry toxins on arthropod natural enemies.

    Science.gov (United States)

    Paula, Débora P; Andow, David A; Bellinati, André; Timbó, Renata Velozo; Souza, Lucas M; Pires, Carmen S S; Sujii, Edison R

    2016-04-01

    Dose-response assays and surrogate species are standard methods for risk analysis for environmental chemicals. These assume that individuals within a species have unimodal responses and that a surrogate species can predict responses of other related taxa. We exposed immature individuals of closely related aphidophagous coccinellid predators, Cycloneda sanguinea and Harmonia axyridis, to Cry1Ac and Cry1F toxins through uniform and constant artificial tritrophic exposure through Myzus persicae aphids. Both toxins were detected in coccinellid pupae, with individual and interspecific variation. Uptake was significantly higher in H. axyridis than in C. sanguinea, both in the proportion of individuals and the concentrations per individual. We also observed bimodal uptake of the Cry toxins by H. axyridis, which indicated that some individuals had low bioaccumulation and some had high bioaccumulation. This suggests that standard dose-response assays need to be interpreted with caution and future assays should examine the modality of the responses. In addition, the similarity in the biological effects of the Cry toxins in the two predators was due to different biological exposure mechanisms. The majority of H. axyridis were exposed both internally and in the gut, while C. sanguinea was exposed primarily in the gut. Thus, despite their close phylogenetic relatedness, these species would not be good surrogates for each other and the surrogate species methodology should be tested more rigorously. PMID:26846212

  20. High serum leptin is an independent risk factor for non-response patients with low viremia to antiviral treatment in chronic hepatitis C

    Institute of Scientific and Technical Information of China (English)

    Yuichiro Eguchi; Toshihiko Mizuta; Tsutomu Yasutake; Akitaka Hisatomi; Ryuichi Iwakiri; Iwata Ozaki; Kazuma Fujimoto

    2006-01-01

    AIM: To determine whether body weight and/or serum leptin were independent predictors of response to antiviral treatment in patients with chronic hepatitis C.METHODS: A retrospective evaluation was performed in 139 patients with chronic hepatitis C treated with interferon (IFN) from 1996 to 2000. Sustained response was defined as negative by hepatitis C virus (HCV) RNA analysis using PCR and normal transaminase at 24 wk after cessation of IFN therapy. Patients who remained positive for HCV RNA at the end of IFN treatment were defined as resistant to IFN therapy. Sex, age, body mass index (BMI) (≥ 25 vs < 25), complication of diabetes mellitus, serum leptin level (≥8.0 μg/L vs <8.0 μg/L),and the stage of liver fibrosis by needle biopsy (FL/F2 vs F3/F4) were examined.RESULTS: Sustained response was achieved in 33 patients (23.7%), while others failed to show a response to IFN therapy. Overall, the factors associated with sustained antiviral effects were HCV-RNA load, HCV genotype, serum leptin level, and stage of liver fibrosis evaluated by univariate analysis. BMI was not associated with any therapeutic effect of IFN. Multivariate analysis indicated that HCV-RNA load was a significant risk factor,but among the patients with low viremia (HCV-RNA < 100 MU/L), leptin level was an independent risk factor for IFN resistance. Namely, a high level of serum leptin attenuated the effect of IFN on both male and female patients with low viremia.CONCLUSION: High serum leptin level is a negative predictor of response to antiviral treatment in chronic hepatitis C with low viremia.

  1. Meningitis Caused by Toscana Virus Is Associated with Strong Antiviral Response in the CNS and Altered Frequency of Blood Antigen-Presenting Cells

    Directory of Open Access Journals (Sweden)

    Stefania Varani

    2015-11-01

    Full Text Available Toscana virus (TOSV is a Phlebotomus-transmitted RNA virus and a frequent cause of human meningitis and meningoencephalitis in Southern Europe during the summer season. While evidence for TOSV-related central nervous system (CNS cases is increasing, little is known about the host defenses against TOSV. We evaluated innate immune response to TOSV by analyzing frequency and activation of blood antigen-presenting cells (APCs and cytokine levels in plasma and cerebrospinal fluid (CSF from patients with TOSV neuroinvasive infection and controls. An altered frequency of different blood APC subsets was observed in TOSV-infected patients, with signs of monocytic deactivation. Nevertheless, a proper or even increased responsiveness of toll-like receptor 3 and 7/8 was observed in blood APCs of these patients as compared to healthy controls. Systemic levels of cytokines remained low in TOSV-infected patients, while levels of anti-inflammatory and antiviral mediators were significantly higher in CSF from TOSV-infected patients as compared to patients with other infectious and noninfectious neurological diseases. Thus, the early host response to TOSV appears effective for viral clearance, by proper response to TLR3 and TLR7/8 agonists in peripheral blood and by a strong and selective antiviral and anti-inflammatory response in the CNS.

  2. Commentary - Physiological variation and phenotypic plasticity: a response to 'Platicity in arthropod cryotypes' by Hawes and Bale

    DEFF Research Database (Denmark)

    Chown, S.L.; Sørensen, Jesper Givskov; Sinclair, B.J.

    2008-01-01

    In a recent publication, Hawes and Bale provide an extended discussion of phenotypic plasticity in the context of low temperature responses of animals. They argue that phenotypic plasticity may be partitioned phylogenetically at several levels and go on to explore these levels, and cold hardiness......' should not be used. We also show that a definition of strategies as cryotypes is not useful and that the hypothesis about the relationship between evolutionary derivation and extent of plasticity in freeze-avoiding vs freeze-tolerant species is not supported by current evidence....

  3. Rapid Virological Response Represents the Highest Prediction Factor of Response to Antiviral Treatment in HCV-Related Chronic Hepatitis: a Multicenter Retrospective Study

    Directory of Open Access Journals (Sweden)

    Federico

    2015-06-01

    Full Text Available Background Standard [i.e. pegylated interferon (Peg-IFN + ribavirin] treatment of hepatitis C virus (HCV-related chronic hepatitis is associated with a sustained virological response (SVR in 50 - 90% of patients. A rapid virological response (RVR (i.e. negative HCV-RNA after 4 weeks of treatment predicts SVR in almost 90% of patients. Objectives The main aim of this study was to assess the strength of RVR, as a predictive factor of antiviral treatment response. Patients and Methods Using univariate and multivariate analysis, we retrospectively evaluated biochemical, metabolic, genetic and viral variables that might affect both RVR and SVR to Peg-IFN plus ribavirin, in 315 consecutive outpatients affected by HCV-related chronic hepatitis. Results At univariate analysis, staging, body mass index, RVR, genotype and viral load were significantly related to SVR (P < 0.001. At multivariate analysis, RVR and genotype remained significant (P < 0.00001. The RVR had a predictive value of 83%. At univariate and multivariate analyses, diabetes (P = 0.003, genotype 2 (P = 0.000 and HCV-RNA values (P = 0.016 were independent predictors of RVR, even though at multivariate analyses, only genotype 2 was significantly related to RVR. When we stratified patients, according to genotype, no laboratory or clinical factors were predictive of RVR in genotype 1 patients at either univariate or multivariate analysis. In genotype 2 patients, staging (P = 0.029 and diabetes (P = 0.001 were the only significant predictors of RVR at univariate analyses, whereas no factor was independently related to RVR, at multivariate analysis. Conclusions The RVR is the strongest factor of SVR and infection with HCV genotype 2 is significantly associated with RVR. Neither biochemical and/or metabolic factors seem to exert influence on RVR.

  4. Inhibition of EHMT2 Induces a Robust Antiviral Response Against Foot-and-Mouth Disease and Vesicular Stomatitis Virus Infections in Bovine Cells.

    Science.gov (United States)

    Singh, Neetu; Ramĩrez-Carvajal, Lisbeth; de Los Santos, Teresa; Golding, Michael C; Long, Charles R

    2016-01-01

    The genetic regulatory network controlling the innate immune system is well understood in many species. However, the role of the epigenetic mechanisms underlying the expression of immunoregulatory genes is less clear, especially in livestock species. Histone H3 lysine 9 dimethylation (H3K9me2) is an epigenetic modification associated with transcriptional silencing within the euchromatin regions. Euchromatic histone-lysine N-methyltransferase 2 (EHMT2; also known as G9a) is a crucial enzyme responsible for regulating the dynamics of this epigenetic modification. It has been shown that histone modifications play a role in regulating type I interferon (IFN) response. In the present study, we investigated the role of EHMT2 in the epigenetic regulation of bovine antiviral innate immunity and explored its therapeutic potential against viral infections. We evaluated the effects of pharmacological and RNAi-mediated inhibition of EHMT2 on the transcription of IFN-β and other IFN-inducible antiviral genes, as well as its effect on foot-and-mouth disease virus (FMDV) and vesicular stomatitis virus (VSV) replication in bovine cells. We show that treatment of primary bovine cells with the synthetic EHMT2 inhibitor (UNC0638) either before or shortly after virus infection resulted in a significant increase in transcript levels of bovine IFN-β (boIFN-β; 300-fold) and other IFN-inducible genes, including IFN-stimulated gene 15 (ISG-15), myxovirus resistance 1 (Mx-1), Mx-2, RIG-I, 2',5'-oligoadenylate synthetase 1 (OAS-1), and protein kinase R (PKR). Expression of these factors correlated with a significant decrease in VSV and FMDV viral titers. Our data confirm the involvement of EHMT2 in the epigenetic regulation of boIFN-β and demonstrate the activation of a general antiviral state after EHMT2 inhibition. PMID:26418342

  5. Accumulation of VH Replacement Products in IgH Genes Derived from Autoimmune Diseases and Anti-Viral Responses in Human.

    Science.gov (United States)

    Lange, Miles D; Huang, Lin; Yu, Yangsheng; Li, Song; Liao, Hongyan; Zemlin, Michael; Su, Kaihong; Zhang, Zhixin

    2014-01-01

    VH replacement refers to RAG-mediated secondary recombination of the IgH genes, which renews almost the entire VH gene coding region but retains a short stretch of nucleotides as a VH replacement footprint at the newly generated VH-DH junction. To explore the biological significance of VH replacement to the antibody repertoire, we developed a Java-based VH replacement footprint analyzer program and analyzed the distribution of VH replacement products in 61,851 human IgH gene sequences downloaded from the NCBI database. The initial assignment of the VH, DH, and JH gene segments provided a comprehensive view of the human IgH repertoire. To our interest, the overall frequency of VH replacement products is 12.1%; the frequencies of VH replacement products in IgH genes using different VH germline genes vary significantly. Importantly, the frequencies of VH replacement products are significantly elevated in IgH genes derived from different autoimmune diseases, including rheumatoid arthritis, systemic lupus erythematosus, and allergic rhinitis, and in IgH genes encoding various autoantibodies or anti-viral antibodies. The identified VH replacement footprints preferentially encoded charged amino acids to elongate IgH CDR3 regions, which may contribute to their autoreactivities or anti-viral functions. Analyses of the mutation status of the identified VH replacement products suggested that they had been actively involved in immune responses. These results provide a global view of the distribution of VH replacement products in human IgH genes, especially in IgH genes derived from autoimmune diseases and anti-viral immune responses.

  6. Glucose-6-Phosphate Dehydrogenase Enhances Antiviral Response through Downregulation of NADPH Sensor HSCARG and Upregulation of NF-κB Signaling

    Directory of Open Access Journals (Sweden)

    Yi-Hsuan Wu

    2015-12-01

    Full Text Available Glucose-6-phosphate dehydrogenase (G6PD-deficient cells are highly susceptible to viral infection. This study examined the mechanism underlying this phenomenon by measuring the expression of antiviral genes—tumor necrosis factor alpha (TNF-α and GTPase myxovirus resistance 1 (MX1—in G6PD-knockdown cells upon human coronavirus 229E (HCoV-229E and enterovirus 71 (EV71 infection. Molecular analysis revealed that the promoter activities of TNF-α and MX1 were downregulated in G6PD-knockdown cells, and that the IκB degradation and DNA binding activity of NF-κB were decreased. The HSCARG protein, a nicotinamide adenine dinucleotide phosphate (NADPH sensor and negative regulator of NF-κB, was upregulated in G6PD-knockdown cells with decreased NADPH/NADP+ ratio. Treatment of G6PD-knockdown cells with siRNA against HSCARG enhanced the DNA binding activity of NF-κB and the expression of TNF-α and MX1, but suppressed the expression of viral genes; however, the overexpression of HSCARG inhibited the antiviral response. Exogenous G6PD or IDH1 expression inhibited the expression of HSCARG, resulting in increased expression of TNF-α and MX1 and reduced viral gene expression upon virus infection. Our findings suggest that the increased susceptibility of the G6PD-knockdown cells to viral infection was due to impaired NF-κB signaling and antiviral response mediated by HSCARG.

  7. Estradiol Enhances CD4+ T-Cell Anti-Viral Immunity by Priming Vaginal DCs to Induce Th17 Responses via an IL-1-Dependent Pathway.

    Science.gov (United States)

    Anipindi, Varun C; Bagri, Puja; Roth, Kristy; Dizzell, Sara E; Nguyen, Philip V; Shaler, Christopher R; Chu, Derek K; Jiménez-Saiz, Rodrigo; Liang, Hong; Swift, Stephanie; Nazli, Aisha; Kafka, Jessica K; Bramson, Jonathan; Xing, Zhou; Jordana, Manel; Wan, Yonghong; Snider, Denis P; Stampfli, Martin R; Kaushic, Charu

    2016-05-01

    Clinical and experimental studies have shown that estradiol (E2) confers protection against HIV and other sexually transmitted infections. Here, we investigated the underlying mechanism. Better protection in E2-treated mice, immunized against genital HSV-2, coincided with earlier recruitment and higher proportions of Th1 and Th17 effector cells in the vagina post-challenge, compared to placebo-treated controls. Vaginal APCs isolated from E2-treated mice induced 10-fold higher Th17 and Th1 responses, compared to APCs from progesterone-treated, placebo-treated, and estradiol-receptor knockout mice in APC-T cell co-cultures. CD11c+ DCs in the vagina were the predominant APC population responsible for priming these Th17 responses, and a potent source of IL-6 and IL-1β, important factors for Th17 differentiation. Th17 responses were abrogated in APC-T cell co-cultures containing IL-1β KO, but not IL-6 KO vaginal DCs, showing that IL-1β is a critical factor for Th17 induction in the genital tract. E2 treatment in vivo directly induced high expression of IL-1β in vaginal DCs, and addition of IL-1β restored Th17 induction by IL-1β KO APCs in co-cultures. Finally, we examined the role of IL-17 in anti-HSV-2 memory T cell responses. IL-17 KO mice were more susceptible to intravaginal HSV-2 challenge, compared to WT controls, and vaginal DCs from these mice were defective at priming efficient Th1 responses in vitro, indicating that IL-17 is important for the generation of efficient anti-viral memory responses. We conclude that the genital mucosa has a unique microenvironment whereby E2 enhances CD4+ T cell anti-viral immunity by priming vaginal DCs to induce Th17 responses through an IL-1-dependent pathway.

  8. Estradiol Enhances CD4+ T-Cell Anti-Viral Immunity by Priming Vaginal DCs to Induce Th17 Responses via an IL-1-Dependent Pathway.

    Directory of Open Access Journals (Sweden)

    Varun C Anipindi

    2016-05-01

    Full Text Available Clinical and experimental studies have shown that estradiol (E2 confers protection against HIV and other sexually transmitted infections. Here, we investigated the underlying mechanism. Better protection in E2-treated mice, immunized against genital HSV-2, coincided with earlier recruitment and higher proportions of Th1 and Th17 effector cells in the vagina post-challenge, compared to placebo-treated controls. Vaginal APCs isolated from E2-treated mice induced 10-fold higher Th17 and Th1 responses, compared to APCs from progesterone-treated, placebo-treated, and estradiol-receptor knockout mice in APC-T cell co-cultures. CD11c+ DCs in the vagina were the predominant APC population responsible for priming these Th17 responses, and a potent source of IL-6 and IL-1β, important factors for Th17 differentiation. Th17 responses were abrogated in APC-T cell co-cultures containing IL-1β KO, but not IL-6 KO vaginal DCs, showing that IL-1β is a critical factor for Th17 induction in the genital tract. E2 treatment in vivo directly induced high expression of IL-1β in vaginal DCs, and addition of IL-1β restored Th17 induction by IL-1β KO APCs in co-cultures. Finally, we examined the role of IL-17 in anti-HSV-2 memory T cell responses. IL-17 KO mice were more susceptible to intravaginal HSV-2 challenge, compared to WT controls, and vaginal DCs from these mice were defective at priming efficient Th1 responses in vitro, indicating that IL-17 is important for the generation of efficient anti-viral memory responses. We conclude that the genital mucosa has a unique microenvironment whereby E2 enhances CD4+ T cell anti-viral immunity by priming vaginal DCs to induce Th17 responses through an IL-1-dependent pathway.

  9. TRIM32 protein modulates type I interferon induction and cellular antiviral response by targeting MITA/STING protein for K63-linked ubiquitination.

    Science.gov (United States)

    Zhang, Jing; Hu, Ming-Ming; Wang, Yan-Yi; Shu, Hong-Bing

    2012-08-17

    Viral infection activates several transcription factors including NF-κB and IRF3, which collaborate to induce type I interferons (IFNs) and innate antiviral response. MITA (also called STING) is a critical adaptor protein that links virus-sensing receptors to IRF3 activation upon infection by both RNA and DNA pathogens. Here we show that the E3 ubiquitin ligase tripartite motif protein 32 (TRIM32) ubiquitinated MITA and dramatically enhanced MITA-mediated induction of IFN-β. Overexpression of TRIM32 potentiated virus-triggered IFNB1 expression and cellular antiviral response. Consistently, knockdown of TRIM32 had opposite effects. TRIM32 interacted with MITA, and was located at the mitochondria and endoplasmic reticulum. TRIM32 targeted MITA for K63-linked ubiquitination at K20/150/224/236 through its E3 ubiquitin ligase activity, which promoted the interaction of MITA with TBK1. These findings suggest that TRIM32 is an important regulatory protein for innate immunity against both RNA and DNA viruses by targeting MITA for K63-linked ubiquitination and downstream activation.

  10. Antibody-independent control of gamma-herpesvirus latency via B cell induction of anti-viral T cell responses.

    OpenAIRE

    Kelly B McClellan; Shivaprakash Gangappa; Speck, Samuel H.; Herbert W Virgin

    2006-01-01

    Synopsis B cells can control virus infection by making specific antibodies that bind to virus and infected cells. However, it is unknown whether B cells perform other anti-viral functions to protect the host during infection. The authors addressed this question by infecting mice with murine γ-herpesvirus 68 (γHV68), a relative of Epstein-Barr virus and Kaposi's sarcoma associated virus, which establishes lifelong latent infection in mice. Mice lacking B cells (B cell−/−) failed to control lat...

  11. De novo characterization of the spleen transcriptome of the large yellow croaker (Pseudosciaena crocea) and analysis of the immune relevant genes and pathways involved in the antiviral response

    KAUST Repository

    Mu, Yinnan

    2014-05-12

    The large yellow croaker (Pseudosciaena crocea) is an economically important marine fish in China. To understand the molecular basis for antiviral defense in this species, we used Illumia paired-end sequencing to characterize the spleen transcriptome of polyriboinosinic:polyribocytidylic acid [poly(I:C)]-induced large yellow croakers. The library produced 56,355,728 reads and assembled into 108,237 contigs. As a result, 15,192 unigenes were found from this transcriptome. Gene ontology analysis showed that 4,759 genes were involved in three major functional categories: biological process, cellular component, and molecular function. We further ascertained that numerous consensus sequences were homologous to known immune-relevant genes. Kyoto Encyclopedia of Genes and Genomes orthology mapping annotated 5,389 unigenes and identified numerous immune-relevant pathways. These immune-relevant genes and pathways revealed major antiviral immunity effectors, including but not limited to: pattern recognition receptors, adaptors and signal transducers, the interferons and interferon-stimulated genes, inflammatory cytokines and receptors, complement components, and B-cell and T-cell antigen activation molecules. Moreover, the partial genes of Toll-like receptor signaling pathway, RIG-I-like receptors signaling pathway, Janus kinase-Signal Transducer and Activator of Transcription (JAK-STAT) signaling pathway, and T-cell receptor (TCR) signaling pathway were found to be changed after poly(I:C) induction by real-time polymerase chain reaction (PCR) analysis, suggesting that these signaling pathways may be regulated by poly(I:C), a viral mimic. Overall, the antivirus-related genes and signaling pathways that were identified in response to poly(I:C) challenge provide valuable leads for further investigation of the antiviral defense mechanism in the large yellow croaker. © 2014 Mu et al.

  12. Hepatitis C Virus and Antiviral Drug Resistance

    Science.gov (United States)

    Kim, Seungtaek; Han, Kwang-Hyub; Ahn, Sang Hoon

    2016-01-01

    Since its discovery in 1989, hepatitis C virus (HCV) has been intensively investigated to understand its biology and develop effective antiviral therapies. The efforts of the previous 25 years have resulted in a better understanding of the virus, and this was facilitated by the development of in vitro cell culture systems for HCV replication. Antiviral treatments and sustained virological responses have also improved from the early interferon monotherapy to the current all-oral regimens using direct-acting antivirals. However, antiviral resistance has become a critical issue in the treatment of chronic hepatitis C, similar to other chronic viral infections, and retreatment options following treatment failure have become important questions. Despite the clinical challenges in the management of chronic hepatitis C, substantial progress has been made in understanding HCV, which may facilitate the investigation of other closely related flaviviruses and lead to the development of antiviral agents against these human pathogens. PMID:27784846

  13. UGT2B28 genomic variation is associated with hepatitis B e-antigen seroconversion in response to antiviral therapy

    Science.gov (United States)

    Liang, Kung-Hao; Lin, Chih-Lang; Hsu, Chao-Wei; Lai, Ming-Wei; Chien, Rong-Nan; Yeh, Chau-Ting

    2016-01-01

    Seroconversion of hepatitis B virus (HBV) e-antigen (HBeAg) is a critical but often-missed therapeutic goal in standard antiviral treatments. An extreme-phenotype genome-wide association study was performed, comparing untreated spontaneous recoverers (with seroconversion of HBV surface antigen) versus entecavir-treated patients failing to achieve HBeAg seroconversion. A single-nucleotide-polymorphism rs2132039 on the UGT2B28 gene, alongside an adjacent copy number polymorphism (CNP605), manifested the strongest clinical associations (P = 3.4 × 10−8 and 0.001, respectively). Multivariate analysis showed that rs2132039-TT genotypes, but not CNP605 copy numbers, remained associated to spontaneous recoverers (P = 0.009). The clinical association of rs2132039 was validated successfully in an independent cohort (n = 302; P = 0.002). Longitudinal case-only analyses revealed that the rs2132039-TT genotype predicted shorter time-to-HBeAg-seroconversion in all antiviral-treated patients (n = 380, P = 0.012), as well as the peginterferon-treated subgroup (n = 123; P = 0.024, Hazard ratio [HR] = 2.104, Confidence interval [CI] = 1.105–4.007). In the entecavir-treated subgroup, the predictive effect was restricted by pretreatment alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels, with effective prediction observed in patients with ALT < 200 IU/ml and ALT/AST ratio <2 (n = 132; P = 0.013, HR = 10.538, CI = 1.420–78.196). PMID:27665939

  14. Successful and Safe Long-Term Standard Antiviral Therapy in a Patient with “Explosive” Immune Response in Course of HCV-Related Liver Cirrhosis

    Directory of Open Access Journals (Sweden)

    Paolo Conca

    2015-06-01

    Full Text Available Hepatitis C virus (HCV has been recognized to be both a hepato- and lymphotropic virus. HCV lymphotropism represents an essential detail in the pathogenesis of virus-related autoimmune and lymphoproliferative disorders, ranging from clonal expansion of B-cells with organ and non-organ-specific autoantibody production up to overt non-Hodgkin’s lymphoma along a continuous step-by-step model of B-cell lymphomagenesis, where the intermediated mixed cryoglobulinemia could be considered as a stage of suppressible antigen-driven lymphoproliferation. The HCV long-lasting extrahepatic replicative state generates an abnormal systemic immunological response, including rheumatoid factor (RF and cryo- and non-cryoprecipitable immune complexes, as well as clinical manifestations, comprising dermatitis, polyarthralgias and arthritis, pulmonary disease, aplastic anemia, glomerulonephritis and vasculitis. The mechanism of these extra-hepatic disorders is thought of as linked to immune complex disease, but their pathogenesis is poorly clarified. Immune-suppressive treatment could induce high-level hepatitis C viremia and impair hepatic disease. We report a female patient, whose chronic HCV-related liver cirrhosis with associated explosive, but oligosymptomatic lymphoproliferative immune response, i.e., RF beyond three thousand times the upper of normal range (unr, type II cryoglobulinemia with cryocrit 40% and monoclonal gammopathy IgM-k, has been successfully and safely treated by long-lasting (sixty-six months combined antiviral therapy (pegylated interferon alfa and ribavirin, at moderate and tapering dose regimen, prolonged for nearly 24 months after the first viral suppression. At the last follow-up (fifty-one months, the patient was showing very-long term antiviral response, progressive decline of secondary immune activation and absence of significant side-effects. Further research is required to fully verify the real impact on therapeutic choice/regimen.

  15. Ecology of herbivorous arthropods in urban landscapes.

    Science.gov (United States)

    Raupp, Michael J; Shrewsbury, Paula M; Herms, Daniel A

    2010-01-01

    Urbanization affects communities of herbivorous arthropods and provides opportunities for dramatic changes in their abundance and richness. Underlying these changes are creation of impervious surfaces; variation in the density, diversity, and complexity of vegetation; and maintenance practices including pulsed inputs of fertilizers, water, and pesticides. A rich body of knowledge provides theoretical underpinnings for predicting and understanding impacts of urbanization on arthropods. However, relatively few studies have elucidated mechanisms that explain patterns of insect and mite abundance and diversity across urbanization gradients. Published accounts suggest that responses to urbanization are often taxon specific, highly variable, and linked to properties of urbanization that weaken top-down and/or bottom-up processes, thereby destabilizing populations of herbivores and their natural enemies. In addition to revealing patterns in diversity and abundance of herbivores across urbanization gradients, a primary objective of this review is to examine mechanisms underlying these patterns and to identify potential hypotheses for future testing.

  16. Spatially selective colonization of the arthropod intestine through activation of Vibrio cholerae biofilm formation

    OpenAIRE

    Purdy, Alexandra E.; Watnick, Paula I.

    2011-01-01

    Vibrio cholerae is an estuarine bacterium and the human pathogen responsible for the diarrheal disease cholera. In the environment, arthropods are proposed to be carriers and reservoirs of V. cholerae. However, the molecular basis of the association between V. cholerae and viable arthropods has not been elucidated previously. Here, we show that the V. cholerae Vibrio polysaccharide (VPS)-dependent biofilm is highly activated upon entry into the arthropod intestine and is specifically required...

  17. Activation of Vago by interferon regulatory factor (IRF) suggests an interferon system-like antiviral mechanism in shrimp.

    Science.gov (United States)

    Li, Chaozheng; Li, Haoyang; Chen, Yixiao; Chen, Yonggui; Wang, Sheng; Weng, Shao-Ping; Xu, Xiaopeng; He, Jianguo

    2015-01-01

    There is a debate on whether invertebrates possess an antiviral immunity similar to the interferon (IFN) system of vertebrates. The Vago gene from arthropods encodes a viral-activated secreted peptide that restricts virus infection through activating the JAK-STAT pathway and is considered to be a cytokine functionally similar to IFN. In this study, the first crustacean IFN regulatory factor (IRF)-like gene was identified in Pacific white shrimp, Litopenaeus vannamei. The L. vannamei IRF showed similar protein nature to mammalian IRFs and could be activated during virus infection. As a transcriptional regulatory factor, L. vannamei IRF could activate the IFN-stimulated response element (ISRE)-containing promoter to regulate the expression of mammalian type I IFNs and initiate an antiviral state in mammalian cells. More importantly, IRF could bind the 5'-untranslated region of L. vannamei Vago4 gene and activate its transcription, suggesting that shrimp Vago may be induced in a similar manner to that of IFNs and supporting the opinion that Vago might function as an IFN-like molecule in invertebrates. These suggested that shrimp might possess an IRF-Vago-JAK/STAT regulatory axis, which is similar to the IRF-IFN-JAK/STAT axis of vertebrates, indicating that invertebrates might possess an IFN system-like antiviral mechanism.

  18. Comparison of Arthropod Prey of Red-Cockaded Woodpeckers on the Boles of Longleaf and Loblolly Pines

    Energy Technology Data Exchange (ETDEWEB)

    Horn, S.; Hanula, J.

    2002-01-01

    Use of knockdown insecticides to sample arthropods on longleaf and loblolly pine to determine which harbored the greater abundance of potential prey. Alterations of longleaf pine bark surface to determine whether bark structure may affect arthropods residing on a tree's bole. Recovery revealed fewer arthropods from scraped trees. Results suggest the bark structure and not the chemical nature of the bark is responsible for differences in arthropod abundance and biomass. Retaining or restoring longleaf pine in red-cockaded woodpecker habitats should increase arthropod availability for this endangered bird and other back-foraging species.

  19. The Matrix Protein of Nipah Virus Targets the E3-Ubiquitin Ligase TRIM6 to Inhibit the IKKε Kinase-Mediated Type-I IFN Antiviral Response.

    Science.gov (United States)

    Bharaj, Preeti; Wang, Yao E; Dawes, Brian E; Yun, Tatyana E; Park, Arnold; Yen, Benjamin; Basler, Christopher F; Freiberg, Alexander N; Lee, Benhur; Rajsbaum, Ricardo

    2016-09-01

    For efficient replication, viruses have developed mechanisms to evade innate immune responses, including the antiviral type-I interferon (IFN-I) system. Nipah virus (NiV), a highly pathogenic member of the Paramyxoviridae family (genus Henipavirus), is known to encode for four P gene-derived viral proteins (P/C/W/V) with IFN-I antagonist functions. Here we report that NiV matrix protein (NiV-M), which is important for virus assembly and budding, can also inhibit IFN-I responses. IFN-I production requires activation of multiple signaling components including the IκB kinase epsilon (IKKε). We previously showed that the E3-ubiquitin ligase TRIM6 catalyzes the synthesis of unanchored K48-linked polyubiquitin chains, which are not covalently attached to any protein, and activate IKKε for induction of IFN-I mediated antiviral responses. Using co-immunoprecipitation assays and confocal microscopy we show here that the NiV-M protein interacts with TRIM6 and promotes TRIM6 degradation. Consequently, NiV-M expression results in reduced levels of unanchored K48-linked polyubiquitin chains associated with IKKε leading to impaired IKKε oligomerization, IKKε autophosphorylation and reduced IFN-mediated responses. This IFN antagonist function of NiV-M requires a conserved lysine residue (K258) in the bipartite nuclear localization signal that is found in divergent henipaviruses. Consistent with this, the matrix proteins of Ghana, Hendra and Cedar viruses were also able to inhibit IFNβ induction. Live NiV infection, but not a recombinant NiV lacking the M protein, reduced the levels of endogenous TRIM6 protein expression. To our knowledge, matrix proteins of paramyxoviruses have never been reported to be involved in innate immune antagonism. We report here a novel mechanism of viral innate immune evasion by targeting TRIM6, IKKε and unanchored polyubiquitin chains. These findings expand the universe of viral IFN antagonism strategies and provide a new potential target for

  20. Easier Control of Late-Onset Cytomegalovirus Disease Following Universal Prophylaxis Through an Early Antiviral Immune Response in Donor-Positive, Recipient-Negative Kidney Transplants.

    Science.gov (United States)

    Kaminski, H; Couzi, L; Garrigue, I; Moreau, J-F; Déchanet-Merville, J; Merville, P

    2016-08-01

    Universal prophylaxis for cytomegalovirus (CMV) prevention is viable but, compared with a preemptive strategy, leads to higher incidence of late-onset disease (LOD) associated with poor patient and graft survival. The purpose of this study was to compare LOD with early onset disease (EOD), with a focus on the highest risk kidney transplant recipients (KTRs): CMV seronegative recipients transplanted from seropositive donors (D+R-). Since CMV control depends on both antiviral treatment and specific immune response, we also compared Vδ2-negative (Vδ2(neg) ) γδ T cell expansion involved in CMV infection resolution. EOD was defined as occurring 3 mo after transplantation. Depending on the period, universal prophylaxis or preemptive treatment was used. Overall, 168 D+R- KTRs were included between 2003 and 2011. LOD was associated with a lower peak DNAemia (p = 0.04), fewer recurrences (odds ratio 0.16; 95% confidence interval 0.05-0.55; p = 0.01) and shorter anti-CMV curative treatment (40 vs. 60 days, p disease, p immune response. These results support the use of universal prophylaxis over a preemptive strategy and reappraise outcomes of LOD. PMID:26953216

  1. A Newly Emergent Turkey Arthritis Reovirus Shows Dominant Enteric Tropism and Induces Significantly Elevated Innate Antiviral and T Helper-1 Cytokine Responses.

    Directory of Open Access Journals (Sweden)

    Tamer A Sharafeldin

    Full Text Available Newly emergent turkey arthritis reoviruses (TARV were isolated from tendons of lame 15-week-old tom turkeys that occasionally had ruptured leg tendons. Experimentally, these TARVs induced remarkable tenosynovitis in gastrocnemius tendons of turkey poults. The current study aimed to characterize the location and the extent of virus replication as well as the cytokine response induced by TARV during the first two weeks of infection. One-week-old male turkeys were inoculated orally with TARV (O'Neil strain. Copy numbers of viral genes were estimated in intestines, internal organs and tendons at ½, 1, 2, 3, 4, 7, 14 days Post inoculation (dpi. Cytokine profile was measured in intestines, spleen and leg tendons at 0, 4, 7 and 14 dpi. Viral copy number peaked in jejunum, cecum and bursa of Fabricius at 4 dpi. Copy numbers increased dramatically in leg tendons at 7 and 14 dpi while minimal copies were detected in internal organs and blood during the same period. Virus was detected in cloacal swabs at 1-2 dpi, and peaked at 14 dpi indicating enterotropism of the virus and its early shedding in feces. Elevation of IFN-α and IFN-β was observed in intestines at 7 dpi as well as a prominent T helper-1 response (IFN-γ at 7 and 14 dpi. IFN-γ and IL-6 were elevated in gastrocnemius tendons at 14 dpi. Elevation of antiviral cytokines in intestines occurred at 7dpi when a significant decline of viral replication in intestines was observed. T helper-1 response in intestines and leg tendons was the dominant T-helper response. These results suggest the possible correlation between viral replication and cytokine response in early infection of TARV in turkeys. Our findings provide novel insights which help elucidate viral pathogenesis in turkey tendons infected with TARV.

  2. INDUCTION OF ANTIVIRAL IMMUNE-RESPONSES BY IMMUNIZATION WITH RECOMBINANT-DNA ENCODED AVIAN CORONAVIRUS NUCLEOCAPSID PROTEIN

    NARCIS (Netherlands)

    BOOTS, AMH; BENAISSATROUW, BJ; HESSELINK, W; RIJKE, E; SCHRIER, C; HENSEN, EJ; Boots, Annemieke

    1992-01-01

    Immune responses to the infectious bronchitis virus (IBV) nucleocapsid protein were studied using a recombinant-DNA expression product. In mice, a lymphocyte proliferative response and a delayed-type hypersensitivity reaction to IBV were induced upon immunization with this nucleocapsid protein. Next

  3. Antiviral activity of hemocyanins

    Directory of Open Access Journals (Sweden)

    P Dolashka,

    2013-11-01

    Full Text Available Hemocyanins are giant biological macromolecules acting as oxygen-transporting glycoproteins. Most of them are respiratory proteins of arthropods and mollusks, but besides they also exhibit protecting effects against bacterial, fungal and viral invasions. As discovered by 2-DGE proteomics analyses, several proteins including hemocyanins of hemocytes from virus-infected arthropods increased upon infection, confirming hemocyanin’s role as part of the organism’s defence system. Based on the structural analyses of molluscan Hcs it is suggested that the carbohydrate chains of the glycoproteins seem to interact with surface-exposed amino acid or carbohydrate residues of the viruses through van der Waals interactions.

  4. Systems biology: A tool for charting the antiviral landscape.

    Science.gov (United States)

    Bowen, James R; Ferris, Martin T; Suthar, Mehul S

    2016-06-15

    The host antiviral programs that are initiated following viral infection form a dynamic and complex web of responses that we have collectively termed as "the antiviral landscape". Conventional approaches to studying antiviral responses have primarily used reductionist systems to assess the function of a single or a limited subset of molecules. Systems biology is a holistic approach that considers the entire system as a whole, rather than individual components or molecules. Systems biology based approaches facilitate an unbiased and comprehensive analysis of the antiviral landscape, while allowing for the discovery of emergent properties that are missed by conventional approaches. The antiviral landscape can be viewed as a hierarchy of complexity, beginning at the whole organism level and progressing downward to isolated tissues, populations of cells, and single cells. In this review, we will discuss how systems biology has been applied to better understand the antiviral landscape at each of these layers. At the organismal level, the Collaborative Cross is an invaluable genetic resource for assessing how genetic diversity influences the antiviral response. Whole tissue and isolated bulk cell transcriptomics serves as a critical tool for the comprehensive analysis of antiviral responses at both the tissue and cellular levels of complexity. Finally, new techniques in single cell analysis are emerging tools that will revolutionize our understanding of how individual cells within a bulk infected cell population contribute to the overall antiviral landscape.

  5. Grassland Arthropods Are Controlled by Direct and Indirect Interactions with Cattle but Are Largely Unaffected by Plant Provenance.

    Directory of Open Access Journals (Sweden)

    Kelly Anne Farrell

    Full Text Available Cattle grazing and invasion by non-native plant species are globally-ubiquitous changes occurring to plant communities that are likely to reverberate through whole food webs. We used a manipulative field experiment to quantify how arthropod community structure differed in native and non-native California grassland communities in the presence and absence of grazing. The arthropod community was strongly affected by cattle grazing: the biovolume of herbivorous arthropods was 79% higher in grazed than ungrazed plots, whereas the biovolume of predatory arthropods was 13% higher in ungrazed plots. In plots where non-native grasses were grazed, arthropod biovolume increased, possibly in response to increased plant productivity or increased nutritional quality of rapidly-growing annual plants. Grazing may thus affect plant biomass both through the direct removal of biomass, and through arthropod-mediated impacts. We also expected the arthropod community to differ between native and non-native plant communities; surprisingly, arthropod richness and diversity did not vary consistently between these grass community types, although arthropod abundance was slightly higher in plots with native and ungrazed grasses. These results suggest that whereas cattle grazing affects the arthropod community via direct and indirect pathways, arthropod community changes commonly associated with non-native plant invasions may not be due to the identity or dominance of the invasive species in those systems, but to accompanying changes in plant traits or functional group composition, not seen in this experiment because of the similarity of the plant communities.

  6. An apoptotic signaling pathway in the interferon antiviral response mediated by RNase L and c-Jun NH2-terminal kinase.

    Science.gov (United States)

    Li, Geqiang; Xiang, Ying; Sabapathy, Kanaga; Silverman, Robert H

    2004-01-01

    Cellular stress responses induced during viral infections are critical to the health and survival of organisms. In higher vertebrates, interferons (IFNs) mediate the innate antiviral response in part through the action of RNase L, a uniquely regulated enzyme. RNase L is activated by 5'-phosphorylated, 2'-5' oligoadenylates (2-5A) produced from IFN-inducible and double stranded RNA-dependent synthetases. We show that viral activation of the c-Jun NH2-terminal kinases (JNK) family of MAP kinases and viral induction of apoptosis are both deficient in mouse cells lacking RNase L. Also, JNK phosphorylation in response to 2-5A was greatly reduced in RNase L-/- mouse cells. In addition, 2-5A treatment of the human ovarian carcinoma cell line, Hey1b, resulted in specific ribosomal RNA cleavage products coinciding with JNK activation. Furthermore, suppression of JNK activity with the chemical inhibitor, SP600125, prevented apoptosis induced by 2-5A. In contrast, inhibition of alternative MAP kinases, p38 and ERK, failed to prevent 2-5A-mediated apoptosis. Short interfering RNA to JNK1/JNK2 mRNAs resulted in JNK ablation while also suppressing 2-5A-mediated apoptosis. Moreover, Jnk1-/- Jnk2-/- cells were highly resistant to the apoptotic effects of IFN and 2-5A. These findings suggest that JNK and RNase L function in an integrated signaling pathway during the IFN response that leads to elimination of virus-infected cells through apoptosis. PMID:14570908

  7. Modulation of Respiratory TLR3-Anti-Viral Response by Probiotic Microorganisms: Lessons Learned from Lactobacillus rhamnosus CRL1505

    OpenAIRE

    KITAZAWA, Haruki; Villena, Julio

    2014-01-01

    Respiratory syncytial virus (RSV) is the leading cause of lower respiratory tract illness in infants and young children. Host immune response is implicated in both protective and immunopathological mechanisms during RSV infection. Activation of Toll-like receptor (TLR)-3 in innate immune cells by RSV can induce airway inflammation, protective immune response, and pulmonary immunopathology. A clear understanding of RSV–host interaction is important for the development of novel and effective th...

  8. [Interferon : antiviral mechanisms and viral escape].

    Science.gov (United States)

    Espert, Lucile; Gongora, Céline; Mechti, Nadir

    2003-02-01

    15 % of human cancers have virus origin, meaning that viruses are the second cause of cancers after tabagism. The knowledge of antiviral mechanisms is essential for treatment and prevention of infection evolution towards cancers. Interferons (IFNs) are a large family of multifunctional cytokines. They are involved in regulation of cell growth and modulation of immune response. But, all these functions seem to converge toward the most important of them : the antiviral activity. IFN secretion is the first event induced by viral infection, and will act on specific receptors on neighbour cells and prevent their infection by inducing numbers of antiviral genes. Although few of them are well known like the PKR, the 2-5OAS/RNase L pathway and the Mx proteins, many others need extensive studies to understand the wide range of IFN effect. Viruses have evolved to circumvent the IFN antiviral activity, and are able not only to divert the cellular machinery but also to lure the antiviral mechanisms of the host cell. The purpose of this review is to describe the many antiviral pathways and proteins induced by IFNs and to summarize the strategies of viral escape. PMID:12660132

  9. Impairment of type I but not type III IFN signaling by hepatitis C virus infection influences antiviral responses in primary human hepatocytes.

    Directory of Open Access Journals (Sweden)

    Jacques Friborg

    Full Text Available Peginterferon lambda-1a (Lambda, a type III interferon (IFN, acts through a unique receptor complex with limited cellular expression outside the liver which may result in a differentiated tolerability profile compared to peginterferon alfa (alfa. In Phase 2b clinical studies, Lambda administered in combination with ribavirin (RBV was efficacious in patients with hepatitis C virus (HCV infection representing genotypes 1 through 4, and was associated with more rapid declines in HCV RNA compared to alfa plus RBV. To gain insights into potential mechanisms for this finding, we investigated the effects of HCV replication on IFN signaling in primary human hepatocytes (PHH and in induced hepatocyte-like cells (iHLCs. HCV infection resulted in rapid down-regulation of the type I IFN-α receptor subunit 1 (IFNAR1 transcript in hepatocytes while the transcriptional level of the unique IFN-λ receptor subunit IL28RA was transiently increased. In line with this observation, IFN signaling was selectively impaired in infected cells upon stimulation with alfa but not in response to Lambda. Importantly, in contrast to alfa, Lambda was able to induce IFN-stimulated gene (ISG expression in HCV-infected hepatocytes, reflecting the onset of innate responses. Moreover, global transcriptome analysis in hepatocytes indicated that Lambda stimulation prolonged the expression of various ISGs that are potentially beneficial to antiviral defense mechanisms. Collectively, these observed effects of HCV infection on IFN receptor expression and signaling within infected hepatocytes provide a possible explanation for the more pronounced early virologic responses observed in patients treated with Lambda compared to alfa.

  10. Synergistic effects of thymoquinone and curcumin on immune response and anti-viral activity against avian influenza virus (H9N2) in turkeys.

    Science.gov (United States)

    Umar, S; Shah, M A A; Munir, M T; Yaqoob, M; Fiaz, M; Anjum, S; Kaboudi, K; Bouzouaia, M; Younus, M; Nisa, Q; Iqbal, M; Umar, W

    2016-07-01

    The main objective of this study was to determine the possible effects of thymoquinone (TQ) and curcumin (Cur) on immune-response and pathogenesis of H9N2 avian influenza virus (AIV) in turkeys. The experiment was performed on 75 non-vaccinated mixed-sex turkey poults, divided into 5 experimental groups (A, B, C, D, and E) of 15 birds each. Group A was kept as non-infected and a non-treated negative control (ctrl group) while group B was kept as infected and non-treated positive control (H9N2 group). Turkeys in groups A and B received normal commercial feed while turkeys in groups C and D received TQ, and Cur respectively, and group E concurrently received TQ and Cur from d one through the entire experiment period. All groups were challenged intra-nasally with H9N2 AIV (A/chicken/Pakistan/10RS3039-284-48/2010) at the fourth wk of age except group A. Infected turkeys showed clinical signs of different severity, showing the most prominent disease signs in turkeys in group B. All infected turkeys showed positive results for virus shedding; however, the pattern of virus shedding was different, and with turkeys in group B showing more pronounced virus secretion than the turkeys in the other groups receiving different levels of TQ and Cur. Moreover, significantly higher antibody titer against H9N2 AIV in turkeys shows the immunomodulatory nature of TQ and Cur. Similarly, increased cytokine gene expression suggests antiviral behavior of TQ and Cur especially in combination, leading to suppressed pathogenesis of H9N2 viruses. However, reduced virus shedding and enhanced immune responses were more pronounced in those turkeys receiving TQ and Cur concurrently. This study showed that supplements of TQ and Cur in combination would significantly enhance immune responsiveness and suppress pathogenicity of influenza viruses in turkeys. PMID:26944958

  11. [2013 update about arthropod envenomations in French Guyana].

    Science.gov (United States)

    Ganteaume, F; Imbert, C

    2014-02-01

    French Guiana, by its geographical situation, its climate and its biodiversity, is often called "the green hell". Indeed, this French department of America shelters a wildlife rich, abundant among which many species of arthropods, some of which are responsible for envenomations. These accidents consist of scorpion's or hymenoptera's stings or spider's bites. The associated clinical aspect is variable, from simple pain to circulatory collapse, or lung oedema. However, symptomatology is generally mild; four deaths associated to arthropod envenomations have been reported in the past 25 years. This article focuses on envenomations in French Guiana, describing favoring human behavior, risks and venoms associated with the main related animal species.

  12. [2013 update about arthropod envenomations in French Guyana].

    Science.gov (United States)

    Ganteaume, F; Imbert, C

    2014-02-01

    French Guiana, by its geographical situation, its climate and its biodiversity, is often called "the green hell". Indeed, this French department of America shelters a wildlife rich, abundant among which many species of arthropods, some of which are responsible for envenomations. These accidents consist of scorpion's or hymenoptera's stings or spider's bites. The associated clinical aspect is variable, from simple pain to circulatory collapse, or lung oedema. However, symptomatology is generally mild; four deaths associated to arthropod envenomations have been reported in the past 25 years. This article focuses on envenomations in French Guiana, describing favoring human behavior, risks and venoms associated with the main related animal species. PMID:24415535

  13. Large scale analysis of pediatric antiviral CD8+ T cell populations reveals sustained, functional and mature responses

    Directory of Open Access Journals (Sweden)

    Northfield John

    2006-12-01

    Full Text Available Abstract Background Cellular immunity plays a crucial role in cytomegalovirus (CMV infection and substantial populations of CMV-specific T cells accumulate throughout life. However, although CMV infection occurs during childhood, relatively little is know about the typical quantity and quality of T cell responses in pediatric populations. Methods One thousand and thirty-six people (Male/Female = 594/442, Age: 0–19 yr.; 959 subjects, 20–29 yr.; 77 subjects were examined for HLA typing. All of 1036 subjects were tested for HLA-A2 antigen. Of 1036 subjects, 887 were also tested for HLA-A23, 24 antigens. In addition, 50 elderly people (Male/Female = 11/39, Age: 60–92 yr. were also tested for HLA-A2 antigen. We analyzed the CD8+ T cell responses to CMV, comparing these to responses in children and young. The frequencies, phenotype and function CD8+ T cells for two imunodominant epitopes from pp65 were measured. Results We observed consistently high frequency and phenotypically "mature" (CD27 low, CD28 low, CD45RA+ CMV-specific CD8+ T cell responses in children, including those studied in the first year of life. These CD8+ T cells retained functionality across all age groups, and showed evidence of memory "inflation" only in later adult life. Conclusion CMV consistently elicits a very strong CD8+ T cell response in infants and large pools of CMV specific CD8+ T cells are maintained throughout childhood. The presence of CMV may considerably mould the CD8+ T cell compartment over time, but the relative frequencies of CMV-specific cells do not show the evidence of a population-level increase during childhood and adulthood. This contrast with the marked expansion ("inflation" of such CD8+ T cells in older adults. This study indicates that large scale analysis of peptide specific T cell responses in infants is readily possible. The robust nature of the responses observed suggests vaccine strategies aimed at priming and boosting CD8+ T cells against

  14. A Quantitative Measurement of Antiviral Activity of Anti-Human Immunodeficiency Virus Type 1 Drugs against Simian Immunodeficiency Virus Infection: Dose-Response Curve Slope Strongly Influences Class-Specific Inhibitory Potential

    OpenAIRE

    Deng, Kai; Zink, M. Christine; Clements, Janice E; Siliciano, Robert F.

    2012-01-01

    Simian immunodeficiency virus (SIV) infection in macaques is so far the best animal model for human immunodeficiency virus type 1 (HIV-1) studies, but suppressing viral replication in infected animals remains challenging. Using a novel single-round infectivity assay, we quantitated the antiviral activities of antiretroviral drugs against SIV. Our results emphasize the importance of the dose-response curve slope in determining the inhibitory potential of antiretroviral drugs and provide useful...

  15. Community Composition and Structure of Soil Macro-Arthropods Under Agricultural Land Uses in the Black Soil Region of Jilin Province, China

    Institute of Scientific and Technical Information of China (English)

    WU Dong-hui; ZHANG Bai; CHEN Peng

    2006-01-01

    Soil macro-arthropods in the black soil region in Jilin Province of China were investigated with the emphasis laid on the species richness and abundance in relation to the types of land-use, i.e., farm yard, farm land and Three-North Forest Shelter Belt. Soil macro-arthropods were hand-sorted in the field. A total of 2 357 soil macro-arthropod individuals was captured and fell into 70 families. The results suggested that type of land use affected the species richness and abundance of soil macro-arthropods. Agricultural practices had a strong impact on the soil macro-arthropods community, the conventional cultivations changed the vertical structure of macro-arthropods in the soil profile, and improved the richness and abundance of macro-arthropods in the lower soil layers especially in July. The results also showed that different groups of soil macro-arthropods had various responses to land use changes.

  16. Modulation of respiratory TLR3-antiviral response by probiotic microorganisms: lessons learned from Lactobacillus rhamnosus CRL1505

    Directory of Open Access Journals (Sweden)

    Haruki eKitazawa

    2014-05-01

    Full Text Available Respiratory syncytial virus (RSV is the leading cause of lower respiratory tract illness in infants and young children. Host immune response is implicated in both protective and immunopathological mechanisms during RSV infection. Activation of Toll-like receptor (TLR-3 in innate immune cells by RSV can induce airway inflammation, protective immune response, and pulmonary immunopathology. Understanding the interaction between RSV and its host is crucial for the development of novel therapeutic strategies as well as safe and effective vaccines. Several studies have centered on whether probiotic microorganisms with the capacity to stimulate the immune system (immunobiotics might sufficiently stimulate the common mucosal immune system to provide protection in the respiratory tract. In this regard, it was demonstrated that some orally administered immunobiotics do have the ability to stimulate respiratory immunity and increase resistance to viral infections. Moreover, during the last decade scientists have significantly advanced in the knowledge of the cellular and molecular mechanisms involved in the protective effect of immunobiotics in the respiratory tract. This review examines the current scientific literature dealing with the use of immunobiotic strains to prevent viral respiratory infections. More specifically, the article discuss the mechanisms involved in the capacity of the immunobiotic strain Lactobacillus rhamnosus CRL1505 to beneficially modulate the immune response triggered by TLR3 activation in the respiratory tract and to increase the resistance to RSV infection in infant mice. In addition, we review the role of interferon (IFN-γ and interleukin (IL-10 in the immunoregulatory effect of the CRL1505 strain that has been successfully used for reducing incidence and morbidity of viral airways infections in children.

  17. Decreased dengue replication and an increased anti-viral humoral response with the use of combined Toll-like receptor 3 and 7/8 agonists in macaques.

    Directory of Open Access Journals (Sweden)

    Carlos A Sariol

    Full Text Available BACKGROUND: Pathogenic versus protective outcomes to Dengue virus (DENV infection are associated with innate immune function. This study aimed to determine the role of increased TLR3- and TLR7/8-mediated innate signaling after Dengue infection of rhesus macaques in vivo to evaluate its impact on disease and anti-DENV immune responses. METHODOLOGY/PRINCIPAL FINDINGS: TLR3 and TLR7/8 agonists (emulsified in Montanide were administered subcutaneously to rhesus macaques at 48 hours and 7 days after DENV infection. The Frequency and activation of myeloid dendritic cells, plasmacytoid dendritic cells, and B cells were measured by flow cytometry while the serum levels of 14 different cytokines and chemokines were quantified. Adaptive immune responses were measured by DENV-specific antibody subtype measurements. Results showed that the combined TLR agonists reduced viral replication and induced the development of a proinflammatory reaction, otherwise absent in Dengue infection alone, without any clear signs of exacerbated disease. Specifically, the TLR-induced response was characterized by activation changes in mDC subsets concurrent with higher serum levels of CXCL-10 and IL-1Ra. TLR stimulation also induced higher titers of anti-DENV antibodies and acted to increase the IgG2/IgG1 ratio of anti-DENV to favor the subtype associated with DENV control. We also observed an effect of DENV-mediated suppression of mDC activation consistent with prior in vitro studies. CONCLUSIONS/SIGNIFICANCE: These data show that concurrent TLR3/7/8 activation of the innate immune response after DENV infection in vivo acts to increase antiviral mechanisms via increased inflammatory and humoral responses in rhesus macaques, resulting in decreased viremia and melioration of the infection. These findings underscore an in vivo protective rather than a pathogenic role for combined TLR3/7/8-mediated activation in Dengue infection of rhesus macaques. Our study provides definitive

  18. The Human Cytomegalovirus Major Immediate-Early Proteins as Antagonists of Intrinsic and Innate Antiviral Host Responses

    Directory of Open Access Journals (Sweden)

    Michael Nevels

    2009-11-01

    Full Text Available The major immediate-early (IE gene of human cytomegalovirus (CMV is believed to have a decisive role in acute infection and its activity is an important indicator of viral reactivation from latency. Although a variety of gene products are expressed from this region, the 72-kDa IE1 and the 86-kDa IE2 nuclear phosphoproteins are the most abundant and important. Both proteins have long been recognized as promiscuous transcriptional regulators. More recently, a critical role of the IE1 and IE2 proteins in counteracting nonadaptive host cell defense mechanisms has been revealed. In this review we will briefly summarize the available literature on IE1- and IE2-dependent mechanisms contributing to CMV evasion from intrinsic and innate immune responses.

  19. Hematopoiesis and hematopoietic organs in arthropods.

    Science.gov (United States)

    Grigorian, Melina; Hartenstein, Volker

    2013-03-01

    Hemocytes (blood cells) are motile cells that move throughout the extracellular space and that exist in all clades of the animal kingdom. Hemocytes play an important role in shaping the extracellular environment and in the immune response. Developmentally, hemocytes are closely related to the epithelial cells lining the vascular system (endothelia) and the body cavity (mesothelia). In vertebrates and insects, common progenitors, called hemangioblasts, give rise to the endothelia and blood cells. In the adult animal, many differentiated hemocytes seem to retain the ability to proliferate; however, in most cases investigated closely, the bulk of hemocyte proliferation takes place in specialized hematopoietic organs. Hematopoietic organs provide an environment where undifferentiated blood stem cells are able to self-renew, and at the same time generate offspring that differentiate into different blood cell types. Hematopoiesis in vertebrates, taking place in the bone marrow, has been subject to intensive research by immunologists and stem cell biologists. Much less is known about blood cell formation in invertebrate animals. In this review, we will survey structural and functional properties of invertebrate hematopoietic organs, with a main focus on insects and other arthropod taxa. We will then discuss similarities, at the molecular and structural level, that are apparent when comparing the development of blood cells in hematopoietic organs of vertebrates and arthropods. Our comparative review is intended to elucidate aspects of the biology of blood stem cells that are more easily missed when focusing on one or a few model species. PMID:23319182

  20. Innate Antiviral Defenses Independent of Inducible IFNα/β Production.

    Science.gov (United States)

    Paludan, Søren R

    2016-09-01

    The type I interferons (IFNs) (IFNα and IFNβ) not only have potent antiviral activities, but also have pathological functions if produced at high levels or over a long time. Recent articles have described antiviral immune mechanisms that are activated in response to virus infection at epithelial surfaces independently of IFNα and IFNβ. This may allow the host to exert rapid local antiviral activity and only induce a full-blown, and potentially pathological, type I IFN response in situations where stronger protective immunity is needed. Here, I describe the emerging understanding of early antiviral defenses, which are independent of type I IFN responses, and also discuss how this enables tissues to exert rapid antiviral activities and to limit type I IFN production. PMID:27345728

  1. Quantitative phase imaging of arthropods

    Science.gov (United States)

    Sridharan, Shamira; Katz, Aron; Soto-Adames, Felipe; Popescu, Gabriel

    2015-01-01

    Abstract. Classification of arthropods is performed by characterization of fine features such as setae and cuticles. An unstained whole arthropod specimen mounted on a slide can be preserved for many decades, but is difficult to study since current methods require sample manipulation or tedious image processing. Spatial light interference microscopy (SLIM) is a quantitative phase imaging (QPI) technique that is an add-on module to a commercial phase contrast microscope. We use SLIM to image a whole organism springtail Ceratophysella denticulata mounted on a slide. This is the first time, to our knowledge, that an entire organism has been imaged using QPI. We also demonstrate the ability of SLIM to image fine structures in addition to providing quantitative data that cannot be obtained by traditional bright field microscopy. PMID:26334858

  2. Quantitative phase imaging of arthropods

    Science.gov (United States)

    Sridharan, Shamira; Katz, Aron; Soto-Adames, Felipe; Popescu, Gabriel

    2015-11-01

    Classification of arthropods is performed by characterization of fine features such as setae and cuticles. An unstained whole arthropod specimen mounted on a slide can be preserved for many decades, but is difficult to study since current methods require sample manipulation or tedious image processing. Spatial light interference microscopy (SLIM) is a quantitative phase imaging (QPI) technique that is an add-on module to a commercial phase contrast microscope. We use SLIM to image a whole organism springtail Ceratophysella denticulata mounted on a slide. This is the first time, to our knowledge, that an entire organism has been imaged using QPI. We also demonstrate the ability of SLIM to image fine structures in addition to providing quantitative data that cannot be obtained by traditional bright field microscopy.

  3. Ophthalmic antiviral chemotherapy : An overview

    Directory of Open Access Journals (Sweden)

    Athmanathan Sreedharan

    1997-01-01

    Full Text Available Antiviral drug development has been slow due to many factors. One such factor is the difficulty to block the viral replication in the cell without adversely affecting the host cell metabolic activity. Most of the antiviral compounds are analogs of purines and pyramidines. Currently available antiviral drugs mainly inhibit viral nucleic acid synthesis, hence act only on actively replicating viruses. This article presents an overview of some of the commonly used antiviral agents in clinical ophthalmology.

  4. Antiviral Drugs: Seasonal Flu

    Centers for Disease Control (CDC) Podcasts

    2010-09-29

    In this podcast, Dr. Joe Bresee explains the nature of antiviral drugs and how they are used for seasonal flu.  Created: 9/29/2010 by National Center for Immunization and Respiratory Diseases (NCIRD).   Date Released: 9/29/2010.

  5. Factors Influencing Arthropod Diversity on Green Roofs

    Directory of Open Access Journals (Sweden)

    Bracha Y. Schindler

    2011-01-01

    Full Text Available Green roofs have potential for providing substantial habitat to plants, birds, and arthropod species that are not well supported by other urban habitats. Whereas the plants on a typical green roof are chosen and planted by people, the arthropods that colonize it can serve as an indicator of the ability of this novel habitat to support a diverse community of organisms. The goal of this observational study was to determine which physical characteristics of a roof or characteristics of its vegetation correlate with arthropod diversity on the roof. We intensively sampled the number of insect families on one roof with pitfall traps and also measured the soil arthropod species richness on six green roofs in the Boston, MA area. We found that the number of arthropod species in soil, and arthropod families in pitfall traps, was positively correlated with living vegetation cover. The number of arthropod species was not significantly correlated with plant diversity, green roof size, distance from the ground, or distance to the nearest vegetated habitat from the roof. Our results suggest that vegetation cover may be more important than vegetation diversity for roof arthropod diversity, at least for the first few years after establishment. Additionally, we found that even green roofs that are small and isolated can support a community of arthropods that include important functional groups of the soil food web.

  6. Knowledge of Arthropod Carnivory and Herbivory: Factors Influencing Preservice Elementary Teacher's Attitudes and Beliefs toward Arthropods

    Science.gov (United States)

    Wagler, Ron; Wagler, Amy

    2013-01-01

    Human negativity toward arthropods has been well documented but the factors that contribute to this negativity have been elusive. This study explored knowledge of arthropod carnivory and herbivory as possible casual factors that contribute to the negative tendencies preservice elementary teachers have toward most arthropods. Specifically, this…

  7. Diet-consumer nitrogen isotope fractionation for prolonged fasting arthropods.

    Science.gov (United States)

    Mizota, Chitoshi; Yamanaka, Toshiro

    2011-12-01

    Nitrogen acquisition for cellular metabolism during diapause is a primary concern for herbivorous arthropods. Analyses of naturally occurring stable isotopes of nitrogen help elucidate the mechanism. Relevant articles have cited (58 times up to mid-June 2011) anomalously elevated δ(15)N (per mil deviation of (15)N/(14)N, relative to atmospheric nitrogen=0 ‰) values (diet-consumer nitrogen isotope fractionation; up to 12 ‰) for a prolonged fasting raspberry beetle (Byturus tomentosus Degeer (Coleoptera: Byturidae)), which feeds on red raspberries (Rubus idaeus: δ(15)N= ~ +2 ‰). Biologists have hypothesised that extensive recycling of amino acid nitrogen is responsible for the prolonged fasting. Since this hypothesis was proposed in 1995, scientists have integrated biochemical and molecular knowledge to support the mechanism of prolonged diapausing of animals. To test the validity of the recycling hypothesis, we analysed tissue nitrogen isotope ratios for four Japanese arthropods: the shield bug Parastrachia japonensis Scott (Hemiptera: Cydnidae), the burrower bug Canthophorus niveimarginatus Scott (Hemiptera: Cydnidae), leaf beetle Gastrophysa atrocyanea Motschulsky (Coleoptera: Chrysomelidae) and the Japanese oak silkworm Antheraea yamamai (Lepidoptera: Saturniidae), all of which fast for more than 6 months as part of their life-history strategy. Resulting diet-consumer nitrogen isotope discrimination during fasting ranged from 0 to 7‰, as in many commonly known terrestrial arthropods. We conclude that prolonged fasting of arthropods does not always result in anomalous diet-consumer nitrogen isotope fractionation, since the recycling process is closed or nearly closed with respect to nitrogen isotopes. PMID:22166153

  8. The IKK Kinases: Operators of Antiviral Signaling

    Directory of Open Access Journals (Sweden)

    Alissa M. Pham

    2010-01-01

    Full Text Available The ability of a cell to combat an intracellular pathogen requires a mechanism to recognize the threat and elicit a transcriptional response against it. In the context of virus infection, the cell must take measures to inhibit viral replication, meanwhile, convey warning signals to neighboring cells of the imminent threat. This immune response is predominantly mediated by the production of cytokines, notably, interferon beta (IFNβ. IFNβ signaling results in the transcriptional induction of over one hundred antiviral gene products whose timely expression renders infected cells more capable of inhibiting virus replication, while providing the uninfected cells with the reinforcements to generate a less permissive cellular environment. Induction of IFNβ and many aspects of the antiviral response pivot on the function of the IKK and IKK-related kinases. Despite sharing high levels of homology and some degree of functional redundancy, the classic IKK kinases: IKKα and IKKβ, and the IKK-related kinases: TBK1 and IKKε, perform distinct roles in regulating the host antiviral defense. These kinases serve as molecular operators in their cooperative ability to integrate incoming cellular cues and act on a range of essential antiviral transcription factors to reshape the cellular transcriptome during infection.

  9. Arthropod Diversity in a Tropical Forest

    DEFF Research Database (Denmark)

    Basset, Yves; Cizek, Lukas; Cuénoud, Philippe;

    2012-01-01

    Most eukaryotic organisms are arthropods. Yet, their diversity in rich terrestrial ecosystems is still unknown. Here we produce tangible estimates of the total species richness of arthropods in a tropical rainforest. Using a comprehensive range of structured protocols, we sampled the phylogenetic...

  10. Noninsect Arthropods in Popular Music

    Directory of Open Access Journals (Sweden)

    Joseph R. Coelho

    2011-05-01

    Full Text Available The occurrence of noninsect arthropods in popular music was examined in order to explore human attitudes toward these species, especially as compared to insects. Crustaceans were the most commonly referenced taxonomic group in artist names, album titles and cover art, followed by spiders and scorpions. The surprising prevalence of crustaceans may be related to the palatability of many of the species. Spiders and scorpions were primarily used for shock value, as well as totemic qualities of strength and ferocity. Spiders were the most abundant group among song titles, perhaps because of their familiarity to the general public. Three noninsect arthropod album titles were found from the early 1970s, then none appear until 1990. Older albums are difficult to find unless they are quite popular, and the resurgence of albums coincides with the rise of the internet. After 1990, issuance of such albums increased approximately linearly. Giant and chimeric album covers were the most common of themes, indicating the use of these animals to inspire fear and surprise. The lyrics of select songs are presented to illustrate the diversity of sentiments present, from camp spookiness to edibility.

  11. Chronic hepatitis C: hepatic iron content does not correlate with response to antiviral therapy Hepatite C crônica: concentração hepática de ferro não é correlacionada com a resposta ao tratamento antiviral

    Directory of Open Access Journals (Sweden)

    Patricia da Silva Fucuta Pereira

    2009-12-01

    Full Text Available The complex interaction between hepatitis C virus infection, iron homeostasis and the response to antiviral treatment remains controversial. The aim of this study was to evaluate the influence of hepatic iron concentration (HIC on the sustained virological response (SVR to antiviral therapy in patients with chronic hepatitis C. A total of 50 patients who underwent pretreatment liver biopsy with assessment of HIC by graphite furnace atomic absorption spectroscopy and were subsequently submitted to antiviral treatment with interferon/peginterferon and ribavirin were included in the study. Patients with alcoholism, history of multiple blood transfusion, chronic kidney disease, hemolytic anemia and parenteral iron therapy were excluded. The iron related markers and HIC were compared between those who achieved an SVR and non-responders (NR patients. The mean age was 45.7 years and the proportion of patients' gender was not different between SVR and NR patients. The median serum iron was 138 and 134 µg/dL (p = 0.9, the median serum ferritin was 152.5 and 179.5 ng/mL (p = 0.87 and the median HIC was 9.9 and 8.2 µmol/g dry tissue (p = 0.51, for SVR and NR patients, respectively. Thus, hepatic iron concentration, determined by a reliable quantitative method, was not a negative predictive factor of SVR in patients with chronic hepatitis C presenting mild to moderate hepatic iron accumulation.A complexa interação entre infecção pelo vírus da hepatite C, homeostase do ferro e resposta ao tratamento antiviral permanece controversa. O objetivo deste estudo foi avaliar a influência da concentração hepática de ferro (CHF na resposta virológica sustentada (RVS à terapia antiviral na hepatite C crônica. Foram incluídos 50 pacientes que foram submetidos à biopsia hepática pré-tratamento com determinação da CHF por espectrofotometria de absorção atômica com forno de grafite e tratados posteriormente com interferon/peginterferon e ribavirina

  12. Bison grazing increases arthropod abundance and diversity in a tallgrass prairie.

    Science.gov (United States)

    Moran, Matthew D

    2014-10-01

    How grazing-induced ecosystem changes by ungulates indirectly affect other consumers is a question of great interest. I investigated the effect of grazing by American Bison (Bos bison L.) on an arthropod community in tallgrass prairie. Grazing increased the abundance of arthropods, an increase that was present in both herbivorous and carnivorous assemblages, but not in detritivores. The increase in herbivores and reduction in plant biomass from grazing resulted in an arthropod herbivore load almost three times higher in grazed plots compared with controls. Among herbivores, the sap-feeding insect guild was dramatically more abundant, while chewing herbivores were not affected. Herbivorous and carnivorous arthropod richness was higher in grazed plots, although the response was strongest among herbivores. Arthropod abundance on individual grasses and forbs was significantly higher in grazed areas, while plant type had no effect on abundance, indicating that the change was ecosystem-wide and not simply in response to a reduction in grass biomass from grazing. The response of arthropods to grazing was strongest in the early part of the growing season. Published research shows that ungulate grazing, although decreasing available biomass to other consumers, enhances plant quality by increasing nitrogen level in plants. The arthropod results of this study suggest higher plant quality outweighs the potential negative competitive effects of plant biomass removal, although other activities of bison could not be ruled out as the causative mechanism. Because arthropods are extremely abundant organisms in grasslands and a food source for other consumers, bison may represent valuable management tools for maintaining biodiversity. PMID:25198902

  13. The effects of the identity of shrub species on the distribution and diversity of ground arthropods in a sandy desert ecosystem of northwestern China

    Institute of Scientific and Technical Information of China (English)

    JiLiang Liu; WenZhi Zhao; FengRui Li

    2014-01-01

    Shrub is an important factor on structuring ground arthropod communities in desert ecosystems. In this study, in order to determine how shrubs and their species influence ground arthropod distribution patterns in a sandy desert scrubland dominated by two different shrub species, Calligonum mongolicum and Nitraria sphaerocarpa, the ground arthropods were sampled with pitfall traps during spring, summer and autumn. At the community level, total arthropod abundance was shown to be significantly higher under shrubs than in intershrub bare areas in spring;similar patterns occurred in terms of the richness of arthropod groups in the spring and over three seasons, suggesting season-specific shrub presence effects on arthropod activity. In addition, more arthropods were found under N. sphaerocarpa shrubs than under C. mongolicum shrubs in autumn, suggesting season-specific effects of shrub species of arthropod activity, whereas more arthropods taxa were captured under C. mongolicum than N. sphaerocarpa. At the trophic group level, the abundances of predator and herbivore arthropods were significantly greater under shrubs than in intershrub bare habitats, whereas herbivore arthropods were more abundant under N. sphaerocarpa than C. mongolicum, and an opposite rule was detected for predator arthropods. At the family level, the mean abundances of Carabidae, Curculionidae, Gnaphosidae and Lycosidae were significantly higher in the shrub microhabitats than in the intershrub bare habitat, there was no significant difference between habitats on the mean abundances of Formicidae and Tenebrionidae. The study results suggested that shrub presence and shrub species variation are important determinants of ground arthropod assemblages in this desert ecosystem, but the responses of ar-thropods differed among trophic and taxonomic groups.

  14. Concordance of sustained virologic response at weeks 4, 12 and 24 post-treatment of hepatitis c in the era of new oral direct-acting antivirals: A concise review.

    Science.gov (United States)

    Burgess, Sarah V; Hussaini, Trana; Yoshida, Eric M

    2016-01-01

    The goal of treatment for chronic hepatitis C viral (HCV) infection is to cure the infection rather than suppress the virus. Historically, a sustained virological response (SVR) defined as undetectable HCV RNA at 24 weeks following the completion of treatment was considered the gold standard to define successful eradication of the virus as a primary endpoint in clinical trials. SVR measured at 12 weeks post-treatment has been shown to be highly concordant with SVR24 in trials of pegylated interferon and ribavirin. The appropriateness and durability of SVR12 as the efficacy endpoint with new oral direct-acting antivirals is less established. A literatura search was performed using PubMed, EMBASE and CENTRAL databases to identify any studies that examined the concordance between SVR24 and earlier time points. Two studies and 4 abstracts were found that performed concordance analyses using positive and negative predictive values. Overall, SVR4 and SVR12 were highly concordant with SVR24 with high positive (> 97%) and negative (> 94%) predictive values; however there was a higher risk of HCV relapse occurring after post-treatment week 4. The majority of the data focused on SVR12 and demonstrated that SVR12 reliably predicted SVR24 in several populations infected with HCV (treatment-naïve, prior null responders, different genotypes) using various new oral direct-acting antiviral regimens. In conclusion, the available data suggests that SVR12 is a reliable assessment of HCV eradication and could be used instead of SVR24 for drug development clinical trials assessing efficacy of new direct-acting antivirals. Data on the long-term durability of SVR12 is still needed.

  15. Biochemical Evolution and Histological Response of Patients with Hepatitis C Undergoing Antiviral Therapy. Evolución bioquímica y respuesta histológica de pacientes con hepatitis C bajo tratamiento antiviral.

    OpenAIRE

    Omar Julián Hernández Ojeda; Marcos Félix Osorio Pagola; Orelvis Martínez Martínez; Denis Monzón Vega; Mabel Vega Galindo

    2011-01-01

    Background: Hepatitis C is a major health problem worldwide and the most common indicator for the need of a liver transplantation in many countries. Objective: To determine the biochemical evolution and the histological response of patients with chronic hepatitis C who were treated with ribavirin and recombinant interferon alfa-

  16. Possible developmental mechanisms underlying the origin of the crown lineages of arthropods

    Institute of Scientific and Technical Information of China (English)

    WANG Xiuqiang; CHEN Junyuan

    2004-01-01

    The extraordinarily preserved, diverse arthropod fauna from the Lower Cambrian Maotianshan shale, central Yunnan (southwest China), represents different evolutionary stages stepping from stem lineages towards crown arthropods (also called euarthropods), which makes this fauna extremely significant for discussion of the origin and early diversification of the arthropods. Anatomical analyses of the Maotianshan shale arthropods strongly indicate that the origin of crown arthropods involved three major evolutionary events, arthrodisation, arthropodisation and cephali- zation. We try to explore possible evolutionary changes of the developmental mechanism that may have underlain origins of euarthropod appendage and head. Fossil evidence suggests that the formation of a jointed limb known as arthropodisation and formation of multi-segmented head (called cephalization), which characterize euarthropods, is an event after arthrodisation characterized with the formation of segmented-exoskeleton and the joint membrane between tergites. We propose that the Hox complex was already operating at least as early as in the Early Cambrian and is responsible for the formation of the joint membrane between two semgents through Hox gene regulation along the D-V and P-D axis. Fossil evidence indicates that the head in ground state of arthropods consists only of two segments, an ocular and an antennal one. The formation of multiple segmented, euarthropod head (called syncephalon) from the two-segmented head was a separate event, which is called cephali- zation. Presence of the Hox gene head expression domain and change of developmental mechanism in head segments might be responsible for the formation of the syncephalon and this event has been broadly finished in the Early Cambrian arthropods. The post-oral limbs in the early syncephalons as evidenced from the Lower Cambrian Maotianshan shale arthropods however were almost identical to those in trunk. Therefore we proposed that the Hox

  17. Arthropods (http://www.iaees.org/publications/journals/arthropods/online-version.asp

    Directory of Open Access Journals (Sweden)

    arthropods@iaees.org

    Full Text Available Arthropods ISSN 2224-4255 URL: http://www.iaees.org/publications/journals/arthropods/online-version.asp RSS: http://www.iaees.org/publications/journals/arthropods/rss.xml E-mail: arthropods@iaees.org Editor-in-Chief: WenJun Zhang Aims and Scope ARTHROPODS (ISSN 2224-4255 is an international journal devoted to the publication of articles on various aspects of arthropods, e.g., ecology, biogeography, systematics, biodiversity (species diversity, genetic diversity, et al., conservation, control, etc. The journal provides a forum for examining the importance of arthropods in biosphere (both terrestrial and marine ecosystems and human life in such fields as agriculture, forestry, fishery, environmental management and human health. The scope of Arthropods is wide and embraces all arthropods-insects, arachnids, crustaceans, centipedes, millipedes, and other arthropods. Articles/short communications on new taxa (species, genus, families, orders, etc. and new records of arthropods are particularly welcome. Authors can submit their works to the email box of this journal, arthropods@iaees.org. All manuscripts submitted to this journal must be previously unpublished and may not be considered for publication elsewhere at any time during review period of this journal. Authors are asked to read Author Guidelines before submitting manuscripts. In addition to free submissions from authors around the world, special issues are also accepted. The organizer of a special issue can collect submissions (yielded from a research project, a research group, etc. on a specific research topic, or submissions of a scientific conference for publication of special issue.

  18. Antiviral Strategies for Pandemic and Seasonal Influenza

    OpenAIRE

    Fang Fang; Maria Hedlund; Larson, Jeffrey L.

    2010-01-01

    While vaccines are the primary public health response to seasonal and pandemic flu, short of a universal vaccine there are inherent limitations to this approach. Antiviral drugs provide valuable alternative options for treatment and prophylaxis of influenza. Here, we will review drugs and drug candidates against influenza with an emphasis on the recent progress of a host-targeting entry-blocker drug candidate, DAS181, a sialidase fusion protein.

  19. Factors Influencing Arthropod Diversity on Green Roofs

    OpenAIRE

    Bracha Y. Schindler; Alden B. Griffith; Kristina N. Jones

    2011-01-01

    Green roofs have potential for providing substantial habitat to plants, birds, and arthropod species that are not well supported by other urban habitats. Whereas the plants on a typical green roof are chosen and planted by people, the arthropods that colonize it can serve as an indicator of the ability of this novel habitat to support a diverse community of organisms. The goal of this observational study was to determine which physical characteristics of a roof or characteristics of its veget...

  20. Antiviral immunity in amphibians.

    Science.gov (United States)

    Chen, Guangchun; Robert, Jacques

    2011-11-01

    Although a variety of virus species can infect amphibians, diseases caused by ranaviruses ([RVs]; Iridoviridae) have become prominent, and are a major concern for biodiversity, agriculture and international trade. The relatively recent and rapid increase in prevalence of RV infections, the wide range of host species infected by RVs, the variability in host resistance among population of the same species and among different developmental stages, all suggest an important involvement of the amphibian immune system. Nevertheless, the roles of the immune system in the etiology of viral diseases in amphibians are still poorly investigated. We review here the current knowledge of antiviral immunity in amphibians, focusing on model species such as the frog Xenopus and the salamander (Ambystoma tigrinum), and on recent progress in generating tools to better understand how host immune defenses control RV infections, pathogenicity, and transmission.

  1. Diagnosis and antiviral intervention strategies for mitigating an influenza epidemic.

    Directory of Open Access Journals (Sweden)

    Robert Moss

    Full Text Available BACKGROUND: Many countries have amassed antiviral stockpiles for pandemic preparedness. Despite extensive trial data and modelling studies, it remains unclear how to make optimal use of antiviral stockpiles within the constraints of healthcare infrastructure. Modelling studies informed recommendations for liberal antiviral distribution in the pandemic phase, primarily to prevent infection, but failed to account for logistical constraints clearly evident during the 2009 H1N1 outbreaks. Here we identify optimal delivery strategies for antiviral interventions accounting for logistical constraints, and so determine how to improve a strategy's impact. METHODS AND FINDINGS: We extend an existing SEIR model to incorporate finite diagnostic and antiviral distribution capacities. We evaluate the impact of using different diagnostic strategies to decide to whom antivirals are delivered. We then determine what additional capacity is required to achieve optimal impact. We identify the importance of sensitive and specific case ascertainment in the early phase of a pandemic response, when the proportion of false-positive presentations may be high. Once a substantial percentage of ILI presentations are caused by the pandemic strain, identification of cases for treatment on syndromic grounds alone results in a greater potential impact than a laboratory-dependent strategy. Our findings reinforce the need for a decentralised system capable of providing timely prophylaxis. CONCLUSIONS: We address specific real-world issues that must be considered in order to improve pandemic preparedness policy in a practical and methodologically sound way. Provision of antivirals on the scale proposed for an effective response is infeasible using traditional public health outbreak management and contact tracing approaches. The results indicate to change the transmission dynamics of an influenza epidemic with an antiviral intervention, a decentralised system is required for

  2. Regulation of antiviral innate immunity by deubiquitinase CYLD

    Institute of Scientific and Technical Information of China (English)

    Minying Zhang; Andrew J Lee; Xuefeng Wu; Shao-Cong Sun

    2011-01-01

    An antiviral innate immune response involves induction of type Ⅰ interferons (IFNs) and their subsequent autocrine and paracrine actions,but the underlying regulatory mechanisms are incompletely understood.Here we report that CYLD,a deubiquitinase that specifically digests lysine 63-1inked ubiquitin chains,is required for antiviral host defense.Loss of CYLD renders mice considerably more susceptible to infection by vesicular stomatitis virus (VSV).Consistently,CYLD-deficient dendritic cells are more sensitive to VSV infection.This functional defect was not due to lack of type I IFN production but rather because of attenuated IFN receptor signaling.In the absence of CYLD,IFN-β is ineffective in the induction of antiviral genes and protection of cells from viral infection.These findings establish CYLD as a novel regulator of antiviral innate immunity and suggest a role for CYLD in regulating IFN receptor signaling.

  3. Biochemical Evolution and Histological Response of Patients with Hepatitis C Undergoing Antiviral Therapy. Evolución bioquímica y respuesta histológica de pacientes con hepatitis C bajo tratamiento antiviral.

    Directory of Open Access Journals (Sweden)

    Omar Julián Hernández Ojeda

    2011-07-01

    Full Text Available

    Background: Hepatitis C is a major health problem worldwide and the most common indicator for the need of a liver transplantation in many countries. Objective: To determine the biochemical evolution and the histological response of patients with chronic hepatitis C who were treated with ribavirin and recombinant interferon alfa-2b in the provincial Hepatology consultation. Methods: A descriptive observational study was conducted. It included 31 patients who presented the hepatitis C virus and were treated in the Hepatology consultation of the Provincial General University Hospital of Cienfuegos "Dr. Aldereguía Gustavo Lima’’ from January 2007 to June 2009. These patients were administered with ribavirin and recombinant interferon alfa-2b. Variables such as age, sex, possible route of infection, aminotransferase alanine serum, biochemical evaluation (after treatment and after follow-up and histological response were included. In order to assess the histological activity of chronic liver injuries Knodell Index was used. In order to compare the results (biochemical and histological response before and after treatment the Sign Test was used. Results: Women were predominant in the sample group (58.1%. The average age was 45.5 ± 11.6 years. The possible route of transmission could not be identified in 51.6% of patients, while surgical treatment was identified as the route of infection in 22.6% of the cases, followed by repeated parenteral treatment in 16.1% of them. Conclusion: By the end of treatment there was a higher response rate in terms of biochemical changes and histological response.

  1. Chemical Space Mapping and Structure-Activity Analysis of the ChEMBL Antiviral Compound Set.

    Science.gov (United States)

    Klimenko, Kyrylo; Marcou, Gilles; Horvath, Dragos; Varnek, Alexandre

    2016-08-22

    Curation, standardization and data fusion of the antiviral information present in the ChEMBL public database led to the definition of a robust data set, providing an association of antiviral compounds to seven broadly defined antiviral activity classes. Generative topographic mapping (GTM) subjected to evolutionary tuning was then used to produce maps of the antiviral chemical space, providing an optimal separation of compound families associated with the different antiviral classes. The ability to pinpoint the specific spots occupied (responsibility patterns) on a map by various classes of antiviral compounds opened the way for a GTM-supported search for privileged structural motifs, typical for each antiviral class. The privileged locations of antiviral classes were analyzed in order to highlight underlying privileged common structural motifs. Unlike in classical medicinal chemistry, where privileged structures are, almost always, predefined scaffolds, privileged structural motif detection based on GTM responsibility patterns has the decisive advantage of being able to automatically capture the nature ("resolution detail"-scaffold, detailed substructure, pharmacophore pattern, etc.) of the relevant structural motifs. Responsibility patterns were found to represent underlying structural motifs of various natures-from very fuzzy (groups of various "interchangeable" similar scaffolds), to the classical scenario in medicinal chemistry (underlying motif actually being the scaffold), to very precisely defined motifs (specifically substituted scaffolds). PMID:27410486

  2. Influenza Round Table: Antiviral Drugs

    Centers for Disease Control (CDC) Podcasts

    2009-11-04

    In this podcast, Dr. Joe Bresee explains the nature of antiviral drugs and how they are used.  Created: 11/4/2009 by National Center for Immunization and Respiratory Diseases (NCIRD).   Date Released: 11/4/2009.

  3. 甜槠凋落叶分解中土壤节肢动物群落结构动态及其对森林片段化的响应%Dynamics of soil arthropod community structure and its responses to forest fragmentation during the decomposition of Castanopsis eyrei leaf litter

    Institute of Scientific and Technical Information of China (English)

    罗媛媛; 袁金凤; 沈国春; 赵谷风; 于明坚

    2011-01-01

    选取浙、闽、赣交界山地5个不同的常绿阔叶林群落(1处连续森林和4处片段化森林),对优势种甜槠凋落叶分解过程中土壤节肢动物动态进行了研究.5个研究样地共获得土壤节肢动物899头,分属9纲25目,其中鳞翅目占个体总数的10%以上,为优势类群;膜翅目、弹尾目、双翅目、前气门亚目和地蜈蚣目为常见类群.凋落叶分解速率与土壤节肢动物的类群数、个体数随季节动态呈现相一致的变化趋势.8月凋落物分解最快,土壤节肢动物类群和个体数最多;而4至6月和12月情况与之相反.片段化森林和连续森林在土壤节肢动物的类群数、个体数和物种多样性方面均显示出差异,面积效应和边缘效应在其中都起了一定的作用.%Five evergreen broad-leaved forests (one continuous forest and four fragmented forests)in the mountain areas in the juncture of Zhejiang, Fujian, and Jiangxi Provinces, East China were selected as test objects to study the dynamics of soil arthropod community structure and its responses to forest fragmentation during the decomposition of dominant tree species Castanopsis eyrei leaf litter. A total of 899 soil arthropods were collected, belonging to 9 classes and 25 orders. Lepidoptera was the dominant taxon, accounting for 10% of the individual, while Hymenoptera, Collembola,Diptera, Prostigmata, and Geophilomorpha were the common taxa. The decomposition rate of C.eyrei leaf litter was the highest in August and lower in April-June and December, which was in accordance with the seasonal dynamics of the taxa number and individual number of soil arthropods.Meanwhile, the taxa number, individual number, and species diversity of soil arthropods differed between continuous forest and fragmented forests, suggesting that both area effect and edge effect affected the dynamics of soil arthropod community structure during the decomposition of C. eyrei leaf litter.

  4. Bioprospecting of Red Sea Sponges for Novel Antiviral Pharmacophores

    KAUST Repository

    O'Rourke, Aubrie

    2015-05-01

    Natural products offer many possibilities for the treatment of disease. More than 70% of the Earth’s surface is ocean, and recent exploration and access has allowed for new additions to this catalog of natural treasures. The Central Red Sea off the coast of Saudi Arabia serves as a newly accessible location, which provides the opportunity to bioprospect marine sponges with the purpose of identifying novel antiviral scaffolds. Antivirals are underrepresented in present day clinical trials, as well as in the academic screens of marine natural product libraries. Here a high-throughput pipeline was initiated by prefacing the antiviral screen with an Image-based High-Content Screening (HCS) technique in order to identify candidates with antiviral potential. Prospective candidates were tested in a biochemical or cell-based assay for the ability to inhibit the NS3 protease of the West Nile Virus (WNV NS protease) as well as replication and reverse transcription of the Human Immunodeficiency Virus 1 (HIV-1). The analytical chemistry techniques of High-Performance Liquid Chromatograpy (HPLC), Liquid Chromatography-Mass Spectrometry (LC-MS), and Nuclear Magnetic Resonance (NMR) where used in order to identify the compounds responsible for the characteristic antiviral activity of the selected sponge fractions. We have identified a 3-alkyl pyridinium from Amphimedon chloros as the causative agent of the observed WNV NS3 protease inhibition in vitro. Additionally, we identified debromohymenialdisine, hymenialdisine, and oroidin from Stylissa carteri as prospective scaffolds capable of HIV-1 inhibition.

  5. Single-epitope DNA vaccination prevents exhaustion and facilitates a broad antiviral CD8+ T cell response during chronic viral infection

    DEFF Research Database (Denmark)

    Bartholdy, Christina; Stryhn, Anette; Christensen, Jan Pravsgaard;

    2004-01-01

    of DNA vaccines encoding immunodominant epitopes of lymphocytic choriomeningitis virus (LCMV). We analyzed the spectrum of the CD8+ T cell response and the susceptibility to infection in H-2(b) and H-2(d) mice. Priming for a monospecific, CD8+ T cell response did not render mice susceptible to viral...... variants. Thus, vaccinated mice were protected against chronic infection with LCMV, and no evidence indicating biologically relevant viral escape was obtained. In parallel, a broad and sustained CD8+ T cell response was generated upon infection, and in H-2(d) mice epitope spreading was observed. Even after...... acute LCMV infection, DNA vaccination did not significantly impair naturally induced immunity. Thus, the response to the other immunogenic epitopes was not dramatically suppressed in DNA-immunized mice undergoing normal immunizing infection, and the majority of mice were protected against rechallenge...

  6. Antiviral defense in shrimp: from innate immunity to viral infection.

    Science.gov (United States)

    Wang, Pei-Hui; Huang, Tianzhi; Zhang, Xiaobo; He, Jian-Guo

    2014-08-01

    The culture of penaeid shrimp is rapidly developing as a major business endeavor worldwide. However, viral diseases have caused huge economic loss in penaeid shrimp culture industries. Knowledge of shrimp innate immunity and antiviral responses has made important progress in recent years, allowing the design of better strategies for the prevention and control of shrimp diseases. In this study, we have updated information on shrimp antiviral immunity and interactions between shrimp hosts and viral pathogens. Current knowledge and recent progress in immune signaling pathways (e.g., Toll/IMD-NF-κB and JAK-STAT signaling pathways), RNAi, phagocytosis, and apoptosis in shrimp antiviral immunity are discussed. The mechanism of viral infection in shrimp hosts and the interactions between viruses and shrimp innate immune systems are also analyzed.

  7. CD8+ cell noncytotoxic antiviral response (CNAR) to HIV in nosocomial HIV-infected individuals%医源性HIV感染者CD8+细胞非细胞毒性HIV抑制作用的研究

    Institute of Scientific and Technical Information of China (English)

    袁霖; 马丽英; 臧希卉; 孟向东; 彭虹; 赵全壁; 邢辉; 邵一鸣

    2008-01-01

    Objective To study the CD8+ cell noncytotoxic antiviral response (CNAR) to HIV in nosocomial HIV infected individuals, and reveal the relationship between the CNAR and CD4 cell count. MethodCD8+ cells from HIV-1 sero-positive individuals were separated by immunomagnetic beads and mixed withCD4+ cells at different CD8 CD4 cell input ratios (2:1,1:1,0.5:1 and 0.25:1). Reverse transcriptase (RT) activity of cocultured supernatant was tested and compared with negative control and the suppression rate of HIV-1 replication was measured. Result The average CD8 : CD4 cell input ratios to reach 80% suppression of HIV replication in the group with CD4300/μl were 2.4:1 and 1.3:1, respectively (P cell count. The ability to suppress HIV replication in subjects with CD4>300 is stronger than those with CD4300个/μl组的平均CD8与CD4比例为1.3:1,两组间比较差异有统计学意义(P300的个体较CD4<300的个体有着更显著的抑制HIV复制的能力.

  8. Folsomia candida (Collembola): a "standard" soil arthropod.

    Science.gov (United States)

    Fountain, Michelle T; Hopkin, Steve P

    2005-01-01

    Folsomia candida Willem 1902, a member of the order Collembola (colloquially called springtails), is a common and widespread arthropod that occurs in soils throughout the world. The species is parthenogenetic and is easy to maintain in the laboratory on a diet of granulated dry yeast. F. candida has been used as a "standard" test organism for more than 40 years for estimating the effects of pesticides and environmental pollutants on nontarget soil arthropods. However, it has also been employed as a model for the investigation of numerous other phenomena such as cold tolerance, quality as a prey item, and effects of microarthropod grazing on pathogenic fungi and mycorrhizae of plant roots. In this comprehensive review, aspects of the life history, ecology, and ecotoxicology of F. candida are covered. We focus on the recent literature, especially studies that have examined the effects of soil pollutants on reproduction in F. candida using the protocol published by the International Standards Organization in 1999.

  9. Role of Arthropods in Maintaining Soil Fertility

    Directory of Open Access Journals (Sweden)

    Thomas W. Culliney

    2013-09-01

    Full Text Available In terms of species richness, arthropods may represent as much as 85% of the soil fauna. They comprise a large proportion of the meso- and macrofauna of the soil. Within the litter/soil system, five groups are chiefly represented: Isopoda, Myriapoda, Insecta, Acari, and Collembola, the latter two being by far the most abundant and diverse. Arthropods function on two of the three broad levels of organization of the soil food web: they are plant litter transformers or ecosystem engineers. Litter transformers fragment, or comminute, and humidify ingested plant debris, which is deposited in feces for further decomposition by micro-organisms, and foster the growth and dispersal of microbial populations. Large quantities of annual litter input may be processed (e.g., up to 60% by termites. The comminuted plant matter in feces presents an increased surface area to attack by micro-organisms, which, through the process of mineralization, convert its organic nutrients into simpler, inorganic compounds available to plants. Ecosystem engineers alter soil structure, mineral and organic matter composition, and hydrology. The burrowing by arthropods, particularly the subterranean network of tunnels and galleries that comprise termite and ant nests, improves soil porosity to provide adequate aeration and water-holding capacity below ground, facilitate root penetration, and prevent surface crusting and erosion of topsoil. Also, the movement of particles from lower horizons to the surface by ants and termites aids in mixing the organic and mineral fractions of the soil. The feces of arthropods are the basis for the formation of soil aggregates and humus, which physically stabilize the soil and increase its capacity to store nutrients.

  10. Arthropod but not bird predation in ethiopian homegardens is higher in tree-poor than in tree-rich landscapes.

    Directory of Open Access Journals (Sweden)

    Debissa Lemessa

    Full Text Available Bird and arthropod predation is often associated with natural pest control in agricultural landscapes, but the rates of predation may vary with the amount of tree cover or other environmental factors. We examined bird and arthropod predation in three tree-rich and three tree-poor landscapes across southwestern Ethiopia. Within each landscape we selected three tree-rich and three tree-poor homegardens in which we recorded the number of tree species and tree stems within 100 × 100 m surrounding the central house. To estimate predation rates, we attached plasticine caterpillars on leaves of two coffee and two avocado shrubs in each homegarden, and recorded the number of attacked caterpillars for 7-9 consecutive weeks. The overall mean daily predation rate was 1.45% for birds and 1.60% for arthropods. The rates of arthropod predation varied among landscapes and were higher in tree-poor landscapes. There was no such difference for birds. Within landscapes, predation rates from birds and arthropods did not vary between tree-rich and tree-poor homegardens in either tree-rich or tree-poor landscapes. The most surprising result was the lack of response by birds to tree cover at either spatial scale. Our results suggest that in tree-poor landscapes there are still enough non-crop habitats to support predatory arthropods and birds to deliver strong top-down effect on crop pests.

  11. Arthropod but not bird predation in ethiopian homegardens is higher in tree-poor than in tree-rich landscapes.

    Science.gov (United States)

    Lemessa, Debissa; Hambäck, Peter A; Hylander, Kristoffer

    2015-01-01

    Bird and arthropod predation is often associated with natural pest control in agricultural landscapes, but the rates of predation may vary with the amount of tree cover or other environmental factors. We examined bird and arthropod predation in three tree-rich and three tree-poor landscapes across southwestern Ethiopia. Within each landscape we selected three tree-rich and three tree-poor homegardens in which we recorded the number of tree species and tree stems within 100 × 100 m surrounding the central house. To estimate predation rates, we attached plasticine caterpillars on leaves of two coffee and two avocado shrubs in each homegarden, and recorded the number of attacked caterpillars for 7-9 consecutive weeks. The overall mean daily predation rate was 1.45% for birds and 1.60% for arthropods. The rates of arthropod predation varied among landscapes and were higher in tree-poor landscapes. There was no such difference for birds. Within landscapes, predation rates from birds and arthropods did not vary between tree-rich and tree-poor homegardens in either tree-rich or tree-poor landscapes. The most surprising result was the lack of response by birds to tree cover at either spatial scale. Our results suggest that in tree-poor landscapes there are still enough non-crop habitats to support predatory arthropods and birds to deliver strong top-down effect on crop pests. PMID:25961306

  12. Experimental Manipulation of Grassland Plant Diversity Induces Complex Shifts in Aboveground Arthropod Diversity.

    Science.gov (United States)

    Hertzog, Lionel R; Meyer, Sebastian T; Weisser, Wolfgang W; Ebeling, Anne

    2016-01-01

    Changes in producer diversity cause multiple changes in consumer communities through various mechanisms. However, past analyses investigating the relationship between plant diversity and arthropod consumers focused only on few aspects of arthropod diversity, e.g. species richness and abundance. Yet, shifts in understudied facets of arthropod diversity like relative abundances or species dominance may have strong effects on arthropod-mediated ecosystem functions. Here we analyze the relationship between plant species richness and arthropod diversity using four complementary diversity indices, namely: abundance, species richness, evenness (equitability of the abundance distribution) and dominance (relative abundance of the dominant species). Along an experimental gradient of plant species richness (1, 2, 4, 8, 16 and 60 plant species), we sampled herbivorous and carnivorous arthropods using pitfall traps and suction sampling during a whole vegetation period. We tested whether plant species richness affects consumer diversity directly (i), or indirectly through increased productivity (ii). Further, we tested the impact of plant community composition on arthropod diversity by testing for the effects of plant functional groups (iii). Abundance and species richness of both herbivores and carnivores increased with increasing plant species richness, but the underlying mechanisms differed between the two trophic groups. While higher species richness in herbivores was caused by an increase in resource diversity, carnivore richness was driven by plant productivity. Evenness of herbivore communities did not change along the gradient in plant species richness, whereas evenness of carnivores declined. The abundance of dominant herbivore species showed no response to changes in plant species richness, but the dominant carnivores were more abundant in species-rich plant communities. The functional composition of plant communities had small impacts on herbivore communities, whereas

  13. [Alpha and beta arthropods diversity from the different environments of Parque Nacional Los Cardones, Salta, Argentina].

    Science.gov (United States)

    Belén Cava, Maria; Antonio Corronca, José; José Echeverría, Alejandro

    2013-12-01

    The essential role of the National Parks is to protect nature, in order to prevent the deterioration and loss of the ecosystem under protection. Very few records about the diversity of arthropods are known from Los Cardones National Park, where three eco-regions are protected: Puna and Monte eco-regions and the High Andean Grassland of the Yungas. Here, we aimed to compare the alpha and beta diversity of arthropods in these eco-regions, and to prove if sites from the same ecoregion, show greater similarity between them in their assemblages, than with sites of the other eco-regions. We also identified arthropod orders with higher species richness, and indicated the families that contribute the most to the registered beta diversity. Three sampling sites were established on each eco-region and the arthropods were sampled using pitfall traps and suction samples. We evaluated the obtained inventory through nonparametric estimators of species richness, and compared diversity among eco-regions through "diversity profiles" and "effective number of species". Beta diversity was assessed by different methods such as the Morisita Index, nonmetric multidimentional scaling analysis, a multiple permutation procedure, and a Similarity Percentage analysis. We recorded 469 spp/morphospecies and recognized three arthropod orders (spiders, dipterans and hymenopterans) that are diverse and abundant in the Park. Besides, the diversity in Los Cardones National Park was found to be high, but it was observed higher in the High Andean Grassland of the Yungas, and lower in the Puna. The inventory obtained was good, reached up to the 81% of the species richness estimated by nonparametric estimators. Each eco-region of the park showed a very particular arthropod community that was tested by a multi-response permutation procedure. The species turnover between eco-regions was high, so that the different environments of the protected area are contributing to the maintenance of the regional

  14. Antiviral Strategies Against Chikungunya Virus.

    Science.gov (United States)

    Abdelnabi, Rana; Neyts, Johan; Delang, Leen

    2016-01-01

    In the last few decades the Chikungunya virus (CHIKV) has evolved from a geographically isolated pathogen to a virus that is widespread in many parts of Africa, Asia and recently also in Central- and South-America. Although CHIKV infections are rarely fatal, the disease can evolve into a chronic stage, which is characterized by persisting polyarthralgia and joint stiffness. This chronic CHIKV infection can severely incapacitate patients for weeks up to several years after the initial infection. Despite the burden of CHIKV infections, no vaccine or antivirals are available yet. The current therapy is therefore only symptomatic and consists of the administration of analgesics, antipyretics, and anti-inflammatory agents. Recently several molecules with various viral or host targets have been identified as CHIKV inhibitors. In this chapter, we summarize the current status of the development of antiviral strategies against CHIKV infections. PMID:27233277

  15. Arthropod Surveillance Programs: Basic Components, Strategies, and Analysis

    OpenAIRE

    Cohnstaedt, Lee W.; Rochon, Kateryn; Duehl, Adrian J.; Anderson, John F.; Barrera, Roberto; Su, Nan-Yao; Gerry, Alec C.; Obenauer, Peter J.; Campbell, James F.; Lysyk, Tim J.; Allan, Sandra A.

    2012-01-01

    Effective entomological surveillance planning stresses a careful consideration of methodology, trapping technologies, and analysis techniques. Herein, the basic principles and technological components of arthropod surveillance plans are described, as promoted in the symposium “Advancements in arthropod monitoring technology, techniques, and analysis” presented at the 58th annual meeting of the Entomological Society of America in San Diego, CA. Interdisciplinary examples of arthropod monitorin...

  16. Environmental and economic impact of alien terrestrial arthropods in Europe

    OpenAIRE

    Sibylle Vaes-Petignat; Wolfgang Nentwig

    2014-01-01

    In the last few decades, the abundance and importance of invasive alien species have grown continuously due to the undiminished growth of global trade. In most cases, arthropod introductions were unintended and occurred as hitchhikers or contaminants. Alien arthropods can have significant environmental impacts and can be economically costly. To measure these impacts, we expand a generic impact scoring system initially developed for mammals and birds, and applied it to terrestrial arthropods. ...

  17. Antibiotic-Mediated Inhibition of Porcine Reproductive and Respiratory Syndrome Virus (PRRSV Infection: A Novel Quinolone Function Which Potentiates the Antiviral Cytokine Response in MARC-145 Cells and Pig Macrophages

    Directory of Open Access Journals (Sweden)

    William A. Cafruny

    2008-01-01

    Full Text Available Porcine reproductive and respiratory syndrome virus (PRRSV is an economically significant agent for which there currently are no effective treatments. Development of antiviral agents for PRRSV as well as many other viruses has been limited by toxicity of known antiviral compounds. In contrast, antibiotics for non-virus microbial infections have been widely useful, in part because of their acceptable toxicity in animals. We report here the discovery that the quinolonecontaining compound Plasmocin™, as well as the quinolones nalidixic acid and ciprofloxacin, have potent anti-PRRSV activity in vitro. PRRSV replication was inhibited by these antibiotics in both cultured MARC-145 cells and cultured primary alveolar porcine macrophages (PAMs. Furthermore, sub-optimal concentrations of nalidixic acid synergized with antiviral cytokines (AK-2 or IFN-γ to quantitatively and qualitatively inhibit PRRSV replication in MARC-145 cells or PAMs. The antiviral activity of Plasmocin and nalidixic acid correlated with reduced actin expression in MARC-145 cells. Replication of the related lactate dehydrogenase-elevating virus (LDV was also inhibited in primary mouse macrophages by Plasmocin. These results are significant to the development of antiviral strategies with potentially reduced toxicity, and provide a model system to better understand regulation of arterivirus replication.

  18. Can antiviral drugs contain pandemic influenza transmission?

    Directory of Open Access Journals (Sweden)

    Niels G Becker

    Full Text Available Antiviral drugs dispensed during the 2009 influenza pandemic generally failed to contain transmission. This poses the question of whether preparedness for a future pandemic should include plans to use antiviral drugs to mitigate transmission.Simulations using a standard transmission model that allows for infected arrivals and delayed vaccination show that attempts to contain transmission require relatively few antiviral doses. In contrast, persistent use of antiviral drugs when the reproduction number remains above 1 use very many doses and are unlikely to reduce the eventual attack rate appreciably unless the stockpile is very large. A second model, in which the community has a household structure, shows that the effectiveness of a strategy of dispensing antiviral drugs to infected households decreases rapidly with time delays in dispensing the antivirals. Using characteristics of past pandemics it is estimated that at least 80% of primary household cases must present upon show of symptoms to have a chance of containing transmission by dispensing antiviral drugs to households. To determine data needs, household outbreaks were simulated with 50% receiving antiviral drugs early and 50% receiving antiviral drugs late. A test to compare the size of household outbreaks indicates that at least 100-200 household outbreaks need to be monitored to find evidence that antiviral drugs can mitigate transmission of the newly emerged virus.Use of antiviral drugs in an early attempt to contain transmission should be part of preparedness plans for a future influenza pandemic. Data on the incidence of the first 350 cases and the eventual attack rates of the first 200 hundred household outbreaks should be used to estimate the initial reproduction number R and the effectiveness of antiviral drugs to mitigate transmission. Use of antiviral drugs to mitigate general transmission should cease if these estimates indicate that containment of transmission is unlikely.

  19. Differential Rickettsial Transcription in Bloodfeeding and Non-Bloodfeeding Arthropod Hosts

    Science.gov (United States)

    Verhoeve, Victoria I.; Jirakanwisal, Krit; Utsuki, Tadanobu; Macaluso, Kevin R.

    2016-01-01

    Crucial factors influencing the epidemiology of Rickettsia felis rickettsiosis include pathogenesis and transmission. Detection of R. felis DNA in a number of arthropod species has been reported, with characterized isolates, R. felis strain LSU and strain LSU-Lb, generated from the cat flea, Ctenocephalides felis, and the non-hematophagous booklouse, Liposcelis bostrychophila, respectively. While it is realized that strain influence on host biology varies, the rickettsial response to these distinct host environments remained undefined. To identify a panel of potential rickettsial transmission determinants in the cat flea, the transcriptional profile for these two strains of R. felis were compared in their arthropod hosts using RNAseq. Rickettsial genes with increased transcription in the flea as compared to the booklouse were identified. Genes previously associated with bacterial virulence including LPS biosynthesis, Type IV secretion system, ABC transporters, and a toxin-antitoxin system were selected for further study. Transcription of putative virulence-associated genes was determined in a flea infection bioassay for both strains of R. felis. A host-dependent transcriptional profile during bloodfeeding, specifically, an increased expression of selected transcripts in newly infected cat fleas and flea feces was detected when compared to arthropod cell culture and incubation in vertebrate blood. Together, these studies have identified novel, host-dependent rickettsial factors that likely contribute to successful horizontal transmission by bloodfeeding arthropods. PMID:27662479

  20. Self protection from anti-viral responses--Ro52 promotes degradation of the transcription factor IRF7 downstream of the viral Toll-Like receptors.

    LENUS (Irish Health Repository)

    Higgs, Rowan

    2010-01-01

    Ro52 is a member of the TRIM family of single-protein E3 ligases and is also a target for autoantibody production in systemic lupus erythematosus and Sjögren\\'s syndrome. We previously demonstrated a novel function of Ro52 in the ubiquitination and proteasomal degradation of IRF3 following TLR3\\/4 stimulation. We now present evidence that Ro52 has a similar role in regulating the stability and activity of IRF7. Endogenous immunoprecipitation of Ro52-bound proteins revealed that IRF7 associates with Ro52, an effect which increases following TLR7 and TLR9 stimulation, suggesting that Ro52 interacts with IRF7 post-pathogen recognition. Furthermore, we show that Ro52 ubiquitinates IRF7 in a dose-dependent manner, resulting in a decrease in total IRF7 expression and a subsequent decrease in IFN-alpha production. IRF7 stability was increased in bone marrow-derived macrophages from Ro52-deficient mice stimulated with imiquimod or CpG-B, consistent with a role for Ro52 in the negative regulation of IRF7 signalling. Taken together, these results suggest that Ro52-mediated ubiquitination promotes the degradation of IRF7 following TLR7 and TLR9 stimulation. As Ro52 is known to be IFN-inducible, this system constitutes a negative-feedback loop that acts to protect the host from the prolonged activation of the immune response.

  1. Antiviral, anti-parasitic, and cytotoxic effects of 5,6-dihydroxyindole (DHI), a reactive compound generated by phenoloxidase during insect immune response.

    Science.gov (United States)

    Zhao, Picheng; Lu, Zhiqiang; Strand, Michael R; Jiang, Haobo

    2011-09-01

    Phenoloxidase (PO) and its activation system are implicated in several defense responses of insects. Upon wounding or infection, inactive prophenoloxidase (proPO) is converted to active PO through a cascade of serine proteases and their homologs. PO generates reactive compounds such as 5,6-dihydroxyindole (DHI), which have a broad-spectrum antibacterial and antifungal activity. Here we report that DHI and its spontaneous oxidation products are also active against viruses and parasitic wasps. Preincubation of a baculovirus stock with 1.25 mM DHI for 3 h near fully disabled recombinant protein production. The LC₅₀ for lambda bacteriophage and eggs of the wasp Microplitis demolitor were 5.6 ± 2.2 and 111.0 ± 1.6 μM, respectively. The toxicity of DHI and related compounds also extended to cells derived from insects that serve as hosts for several of the aforementioned pathogens. Pretreatment of Sf9 cells with 1.0 mM DHI for 4 h resulted in 97% mortality, and LC₅₀ values of 20.3 ± 1.2 μM in buffer and 131.8 ± 1.1 μM in a culture medium. Symptoms of DHI toxicity in Sf9 cells included DNA polymerization, protein crosslinking, and lysis. Taken together, these data showed that proPO activation and DHI production is strongly toxic against various pathogens but can also damage host tissues and cells if not properly controlled.

  2. Longitudinal fluctuations in PD1 and PD-L1 expression in association with changes in anti-viral immune response in chronic hepatitis B

    Directory of Open Access Journals (Sweden)

    Wenjin Zhang

    2012-08-01

    Full Text Available Abstract Background Controversy exists regarding the role of PD1 and its ligand PD-L1 in chronic hepatitis B infection. In some studies, persistent HBV infection has been attributed to high levels of PD-1 and PD-L1 expression on HBV-specific T-cells and antigen-presenting cells (APCs respectively. Other studies revealed that the up-regulation of PD-1 and PD-L1 during an acute inflammation phase is required to offset increasing positive co-stimulatory signals to avoid severe damage by an over-vigorous immune response. Methods Fifteen chronic hepatitis B patients, with inflammatory flare episode, were recruited prospectively. Based on serum HBV-DNA, HBsAg load, and ALT values, inflammatory flare episode were divided into initial, climax, decline and regression phase. Blood sample and liver biopsy tissues from each individual were taken in these 4 phases respectively. Circulating and intra-hepatic PD1 and PD-L1 expression levels were monitored throughout the inflammatory flare episode by flow cytometry and immunostaining and these expression levels were related to the HBV-specific T-cell changes, expression of pro-inflammatory cytokines, HBV-DNA replication and HBV antigen load. Results ]The levels of PD-1 and PD-L1 expressions were significantly up-regulated in the inflammation ascending phase, initial and climax period and in parallel with HBV-specific colon expansion. It showed increasing the level of serum ALT and decreasing the HBV-DNA loads. As the level of inflammation reduced, the circulating and intra-hepatic PD1 and circulating PD-L1 decreased progressively in concordance with serum ALT, HBV-DNA and HBsAg loads decreased except intra-hepatic PD-1 expression. Intra-hepatic PD-L1 expression did not decrease significantly during the regression phase of inflammation compared to that in prior period. The intra-hepatic PD-L1 expression remained relatively on higher level when serum HBV-DNA load and ALT decreased to approximately normal range

  3. Identification of orange-spotted grouper (Epinephelus coioides) interferon regulatory factor 3 involved in antiviral immune response against fish RNA virus.

    Science.gov (United States)

    Huang, Youhua; Huang, Xiaohong; Cai, Jia; OuYang, Zhengliang; Wei, Shina; Wei, Jingguang; Qin, Qiwei

    2015-02-01

    Interferon regulatory factor 3 (IRF3) is an important transcription factor which regulates the expression of interferon (IFN) and IFN-stimulated genes (ISGs) following virus recognition. In this study, a novel IRF3 gene was cloned from grouper Epinephelus coioides (EcIRF3) and its effects against Singapore grouper iridovirus (SGIV) and red spotted grouper nervous necrosis virus (RGNNV) was investigated. The full-length of EcIRF3 cDNA was composed of 2513 bp and encoded a polypeptide of 458 amino acids which shared 82% identity with European seabass (Dicentrarchus labrax). EcIRF3 contained three conserved domains including a DNA-binding domain (DBD), an IRF associated domain (IAD) and a serine-rich domain. Expression profile analysis revealed that EcIRF3 was abundant in head kidney, kidney, spleen and gill. Upon different stimuli in vitro, the transcript of EcIRF3 was significantly up-regulated after RGNNV infection or treatment with polyinosin-polycytidylic acid (poly I:C). During SGIV infection, the increase of the EcIRF3 transcription was only detected at the late stage, suggesting that EcIRF3 was differently regulated by different stimuli. Immune fluorescence assay indicated that the fluorescence signal of EcIRF3 was increased significantly after infection with RGNNV or treatment with poly I:C, but moderately at the late stage of SGIV infection. Reporter gene assay showed that EcIRF3 activated zebrafish type I IFN and type III IFN promoter in vitro. The viral gene transcription and virus production of RGNNV were significantly decreased in EcIRF3 overexpressing cells. However, the ectopic expression of EcIRF3 did not affect the gene transcription and virus production of SGIV. Moreover, the mRNA expression levels of type I IFN and IFN-inducible genes (MxI, ISG15 and ISG56) were increased in RGNNV infected EcIRF3 overexpressing cells compared to empty vector transfected cells. Together, our results demonstrated that IFN immune response mediated by grouper IRF3 was

  4. Repeated Raking of Pine Plantations Alters Soil Arthropod Communities

    Directory of Open Access Journals (Sweden)

    Holly K. Ober

    2014-04-01

    Full Text Available Terrestrial arthropods in forests are engaged in vital ecosystem functions that ultimately help maintain soil productivity. Repeated disturbance can cause abrupt and irreversible changes in arthropod community composition and thereby alter trophic interactions among soil fauna. An increasingly popular means of generating income from pine plantations in the Southeastern U.S. is annual raking to collect pine litter. We raked litter once per year for three consecutive years in the pine plantations of three different species (loblolly, Pinus taeda; longleaf, P. palustris; and slash, P. elliottii. We sampled arthropods quarterly for three years in raked and un-raked pine stands to assess temporal shifts in abundance among dominant orders of arthropods. Effects varied greatly among orders of arthropods, among timber types, and among years. Distinct trends over time were apparent among orders that occupied both high trophic positions (predators and low trophic positions (fungivores, detritivores. Multivariate analyses demonstrated that raking caused stronger shifts in arthropod community composition in longleaf and loblolly than slash pine stands. Results highlight the role of pine litter in shaping terrestrial arthropod communities, and imply that repeated removal of pine straw during consecutive years is likely to have unintended consequences on arthropod communities that exacerbate over time.

  5. Arthropod Borne Diseases in Imposed War during 1980-88

    Directory of Open Access Journals (Sweden)

    M Khoobdel

    2008-06-01

    Full Text Available Background: Personnel of military forces have close contact with natural habitat and usually encounter with bite of arthropods and prone to be infected with arthropod borne diseases. The imposed war against Iran was one of the most important and the longest war in the Middle East and even in the world and military people faced various diseases. The aim of this study was to review prevalence of arthropod borne diseases and to collect relevant information and valuable experiences during the imposed war.Methods: The present survey is a historical research and cross-sectional study, focused on arthropod fauna, situation of different arthropod borne diseases and also the ways which military personnel used to protect themselves against them. The information was adopted from valid military health files and also interviewing people who participated in the war.Results: Scabies, cutaneous leishmaniasis, sandfly fever and pediculosis were more prevalent among other arthropod -borne diseases in Iran-Iraq war. Measures to control arthropods and diseases at wartime mainly included: scheduled spraying of pesticides, leishmanization and treatment of patients.Conclusion: Although measures used during the war to control arthropods were proper, however, due to needs and importance of military forces to new equipment and technologies, it is recommended to use deltamethrin-impreg­nated bed net, permethrin treated military uniforms and various insect repellents in future.

  6. Soil arthropods as test organisms for ecotoxicology

    Energy Technology Data Exchange (ETDEWEB)

    Iglisch, I.

    1981-02-01

    The importance of arthropods - organisms which usually grow in masses - for soil biology depends on their capacity to participate in the continuous transformation of organic substances within the relevant biocenosis and thus to take part in the maintenance of the ecological balance. In ecotoxicology, i.e. the science of substances having a detrimental effect on the natural balance of ecosystems, we try to find ways to evaluate risk of substances hazardous to the environment. In principle, biocenoses would offer themselves in their entirety as appropriate test objects for ecotoxicological evaluation of chemicals. Since it will not yet be possible in the near future to carry out this kind of studies, individual organisms proved as representatives of terrestial biotopes have to be chosen for these purposes. Primarily, Collembola, Coleoptera, and Diptera (larvae) are part of the meso- and macrofauna of soil arthropods or soil insects according to the experience made up to now in respect of their importance for soil biology. Representatives of such organisms should be used to develop test procedures to indicate damage even of a subacute, chronic nature or the impairment of their functional performance the maintance of which is a prerequisite for the ecological balance.

  7. A molecular palaeobiological exploration of arthropod terrestrialization

    Science.gov (United States)

    Carton, Robert; Edgecombe, Gregory D.

    2016-01-01

    Understanding animal terrestrialization, the process through which animals colonized the land, is crucial to clarify extant biodiversity and biological adaptation. Arthropoda (insects, spiders, centipedes and their allies) represent the largest majority of terrestrial biodiversity. Here we implemented a molecular palaeobiological approach, merging molecular and fossil evidence, to elucidate the deepest history of the terrestrial arthropods. We focused on the three independent, Palaeozoic arthropod terrestrialization events (those of Myriapoda, Hexapoda and Arachnida) and showed that a marine route to the colonization of land is the most likely scenario. Molecular clock analyses confirmed an origin for the three terrestrial lineages bracketed between the Cambrian and the Silurian. While molecular divergence times for Arachnida are consistent with the fossil record, Myriapoda are inferred to have colonized land earlier, substantially predating trace or body fossil evidence. An estimated origin of myriapods by the Early Cambrian precedes the appearance of embryophytes and perhaps even terrestrial fungi, raising the possibility that terrestrialization had independent origins in crown-group myriapod lineages, consistent with morphological arguments for convergence in tracheal systems. This article is part of the themed issue ‘Dating species divergences using rocks and clocks’. PMID:27325830

  8. Environmental and economic impact of alien terrestrial arthropods in Europe

    Directory of Open Access Journals (Sweden)

    Sibylle Vaes-Petignat

    2014-06-01

    Full Text Available In the last decades abundance and importance of invasive alien species has grown continuously due to the undiminished growth of global trade. In most cases, arthropod introductions were unintended and occurred as hitchhikers or contaminants. Alien arthropods can have significant environmental impacts and can be economically costly. To measure these impacts, we expand the generic impact scoring system initially developed for mammals and birds, and applied it to terrestrial arthropods. The scoring of the 77 most widely distributed arthropod species alien to Europe revealed the mite Varroa destructor as the most harmful species, followed by the Chinese longhorn beetle Anoplophora chinensis and the Argentine ant Linepithema humile. The highest environmental impact is through herbivory, disease transmission, and ecosystem impacts. The highest economic impact is on agriculture and human infrastructure. The generic impact scoring system allows comparing impact scores of vertebrates and arthropods, thus serving as a background for decision making processes of policies and stakeholders.

  9. What You Should Know about Flu Antiviral Drugs

    Science.gov (United States)

    ... this? Submit What's this? Submit Button Past Newsletters What You Should Know About Flu Antiviral Drugs Language: ... that can be used to treat flu illness. What are antiviral drugs? Antiviral drugs are prescription medicines ( ...

  10. Antiviral effects of Glycyrrhiza species.

    Science.gov (United States)

    Fiore, Cristina; Eisenhut, Michael; Krausse, Rea; Ragazzi, Eugenio; Pellati, Donatella; Armanini, Decio; Bielenberg, Jens

    2008-02-01

    Historical sources for the use of Glycyrrhiza species include ancient manuscripts from China, India and Greece. They all mention its use for symptoms of viral respiratory tract infections and hepatitis. Randomized controlled trials confirmed that the Glycyrrhiza glabra derived compound glycyrrhizin and its derivatives reduced hepatocellular damage in chronic hepatitis B and C. In hepatitis C virus-induced cirrhosis the risk of hepatocellular carcinoma was reduced. Animal studies demonstrated a reduction of mortality and viral activity in herpes simplex virus encephalitis and influenza A virus pneumonia. In vitro studies revealed antiviral activity against HIV-1, SARS related coronavirus, respiratory syncytial virus, arboviruses, vaccinia virus and vesicular stomatitis virus. Mechanisms for antiviral activity of Glycyrrhiza spp. include reduced transport to the membrane and sialylation of hepatitis B virus surface antigen, reduction of membrane fluidity leading to inhibition of fusion of the viral membrane of HIV-1 with the cell, induction of interferon gamma in T-cells, inhibition of phosphorylating enzymes in vesicular stomatitis virus infection and reduction of viral latency. Future research needs to explore the potency of compounds derived from licorice in prevention and treatment of influenza A virus pneumonia and as an adjuvant treatment in patients infected with HIV resistant to antiretroviral drugs. PMID:17886224

  11. Antiviral targets of human noroviruses.

    Science.gov (United States)

    Prasad, Bv Venkataram; Shanker, Sreejesh; Muhaxhiri, Zana; Deng, Lisheng; Choi, Jae-Mun; Estes, Mary K; Song, Yongcheng; Palzkill, Timothy; Atmar, Robert L

    2016-06-01

    Human noroviruses are major causative agents of sporadic and epidemic gastroenteritis both in children and adults. Currently there are no licensed therapeutic intervention measures either in terms of vaccines or drugs available for these highly contagious human pathogens. Genetic and antigenic diversity of these viruses, rapid emergence of new strains, and their ability to infect a broad population by using polymorphic histo-blood group antigens for cell attachment, pose significant challenges for the development of effective antiviral agents. Despite these impediments, there is progress in the design and development of therapeutic agents. These include capsid-based candidate vaccines, and potential antivirals either in the form of glycomimetics or designer antibodies that block HBGA binding, as well as those that target essential non-structural proteins such as the viral protease and RNA-dependent RNA polymerase. In addition to these classical approaches, recent studies suggest the possibility of interferons and targeting host cell factors as viable approaches to counter norovirus infection. This review provides a brief overview of this progress. PMID:27318434

  12. Hepatitis C virus: Virology, diagnosis and management of antiviral therapy

    Institute of Scientific and Technical Information of China (English)

    Stéphane Chevaliez; Jean-Michel Pawlotsky

    2007-01-01

    Hepatitis C virus (HCV) infects approximately 170 million individuals worldwide. Prevention of HCV infection complications is based on antiviral therapy with the combination of pegylatecl interferon alfa and ribavirin.The use of serological and virological tests has become essential in the management of HCV infection in order to diagnose infection, guide treatment decisions and assess the virological response to antiviral therapy. Anti-HCV antibody testing and HCV RNA testing are used to diagnose acute and chronic hepatitis C. The HCV genotype should be systematically determined before treatment, as it determines the indication, the duration of treatment,the dose of ribavirin and the virological monitoring procedure. HCV RNA monitoring during therapy is used to tailor treatment duration in HCV genotype 1 infection, and molecular assays are used to assess the end-of-treatment and, most importantly the sustained virological response,i.e. the enlpoint of therapy.

  13. Evaluating potential risks of transgenic arthropods for pest management programmes

    International Nuclear Information System (INIS)

    Genetic modification using recombinant DNA methods can now be used, almost routinely, to transform pest and beneficial arthropods and such genetically engineered insects and mites could be used to improve pest management programs. Genetic manipulation with recombinant DNA techniques may generate concerns about risk, requiring additional time and resources to resolve. Risk assessments must be conducted prior to releasing transgenic arthropods into the environment for either short term experiments or permanent establishment. Potential risk issues to be resolved include whether: the inserted gene(s) (trait) is stable; the traits can be horizontally transferred to other populations or species; released arthropods will perform as expected (especially with regard to their geographic distribution, host or prey specificity; released arthropods will have unintended environmental effects; and, in the case of short term releases, the released arthropods can be recovered from field sites. If the transgenic arthropods strain(s) perform well in preliminary, short term releases and risk assessments are completed satisfactorily, permanent releases into the environment may follow. Many pest management programs, especially those involving replacement of pest populations by the transgenic population, will require permanent establishment in the environment and the use of 'drive mechanisms', have been proposed to achieve this. Because efficacy can be severely compromised by 'transgene silencing', plant molecular biologists are now attempting to stabilize gene expression by building in 'insulators'. Transgene silencing occurs in Drosophila and will no doubt be a factor in other transgenic arthropods. (author)

  14. Role of arthropod communities in bioenergy crop litter decomposition†.

    Science.gov (United States)

    Zangerl, Arthur R; Miresmailli, Saber; Nabity, Paul; Lawrance, Allen; Yanahan, Alan; Mitchell, Corey A; Anderson-Teixeira, Kristina J; David, Mark B; Berenbaum, May R; DeLucia, Evan H

    2013-10-01

    The extensive land use conversion expected to occur to meet demands for bioenergy feedstock production will likely have widespread impacts on agroecosystem biodiversity and ecosystem services, including carbon sequestration. Although arthropod detritivores are known to contribute to litter decomposition and thus energy flow and nutrient cycling in many plant communities, their importance in bioenergy feedstock communities has not yet been assessed. We undertook an experimental study quantifying rates of litter mass loss and nutrient cycling in the presence and absence of these organisms in three bioenergy feedstock crops-miscanthus (Miscanthus x giganteus), switchgrass (Panicum virgatum), and a planted prairie community. Overall arthropod abundance and litter decomposition rates were similar in all three communities. Despite effective reduction of arthropods in experimental plots via insecticide application, litter decomposition rates, inorganic nitrogen leaching, and carbon-nitrogen ratios did not differ significantly between control (with arthropods) and treatment (without arthropods) plots in any of the three community types. Our findings suggest that changes in arthropod faunal composition associated with widespread adoption of bioenergy feedstock crops may not be associated with profoundly altered arthropod-mediated litter decomposition and nutrient release.

  15. Diversity of arthropod community in transgenic poplar-cotton ecosystems.

    Science.gov (United States)

    Zhang, D J; Lu, Z Y; Liu, J X; Li, C L; Yang, M S

    2015-01-01

    Poplar-cotton agro-ecosystems are the main agricultural planting modes of plain cotton fields in China. Here, we performed a systematic survey of the diversity and population of arthropod communities in four different combination of poplar-cotton eco-systems, including I) non-transgenic poplar and non-transgenic cotton fields; II) non-transgenic poplar and transgenic cotton fields [Bacillus thuringiensis (Bt) cotton]; III) Bt transgenic poplar (high insect resistant strain Pb29) and non-transgenic cotton; and IV) transgenic poplar and transgenic cotton fields, over a period of 3 years. Based on the statistical methods used to investigate community ecology, the effects of transgenic ecosystems on the whole structure of the arthropod community, on the structure of arthropods in the nutritive layer, and on the similarity of arthropod communities were evaluated. The main results were as follows: the transgenic poplar-cotton ecosystem has a stronger inhibitory effect on insect pests and has no impact on the structure of the arthropod community, and therefore, maintains the diversity of the arthropod community. The character index of the community indicated that the structure of the arthropod community of the transgenic poplar-cotton ecosystem was better than that of the poplar-cotton ecosystem, and that system IV had the best structure. As for the abundance of nutritional classes, the transgenic poplar-cotton ecosystem was also better than that of the non-transgenic poplar-cotton ecosystem. The cluster analysis and similarity of arthropod communities between the four different transgenic poplar-cotton ecosystems illustrated that the structure of the arthropod community excelled in the small sample of the transgenic poplar-cotton ecosystems.

  16. Antiviral active peptide from oyster

    Science.gov (United States)

    Zeng, Mingyong; Cui, Wenxuan; Zhao, Yuanhui; Liu, Zunying; Dong, Shiyuan; Guo, Yao

    2008-08-01

    An active peptide against herpes virus was isolated from the enzymic hydrolysate of oyster ( Crassostrea gigas) and purified with the definite direction hydrolysis technique in the order of alcalase and bromelin. The hydrolysate was fractioned into four ranges of molecular weight (>10 kDa, 10 5 kDa, 5 1 kDa and <1 kDa) using ultrafiltration membranes and dialysis. The fraction of 10 5 kDa was purified using consecutive chromatographic methods including DEAE Sephadex A-25 column, Sephadex G-25 column, and high performance liquid chromatogram (HPLC) by activity-guided isolation. The antiviral effect of the obtained peptide on herpetic virus was investigated in Vero cells by observing cytopathic effect (CPE). The result shows that the peptide has high inhibitory activity on herpetic virus.

  17. Antiviral active peptide from oyster

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    An active peptide against herpes virus was isolated from the enzymic hydrolysate of oyster (Crassostrea gigas) and purified with the definite direction hydrolysis technique in the order of alcalase and bromelin. The hydrolysate was fractioned into four ranges of molecular weight (>10 kDa, 10-5 kDa, 5-1 kDa and <1 kDa) using ultrafiltration membranes and dialysis. The fraction of 10?5 kDa was purified using consecutive chromatographic methods including DEAE Sephadex A-25 column, Sephadex G-25 column, and high performance liquid chromatogram (HPLC) by activity-guided isolation. The antiviral effect of the obtained peptide on herpetic virus was investigated in Vero cells by observing cytopathic effect (CPE). The result shows that the peptide has high inhibitory activity on herpetic virus.

  18. Antiviral Perspectives for Chikungunya Virus

    Directory of Open Access Journals (Sweden)

    Deepti Parashar

    2014-01-01

    Full Text Available Chikungunya virus (CHIKV is a mosquito-borne pathogen that has a major health impact in humans and causes acute febrile illness in humans accompanied by joint pains and, in many cases, persistent arthralgia lasting for weeks to years. CHIKV reemerged in 2005-2006 in several parts of the Indian Ocean islands and India after a gap of 32 years, causing millions of cases. The re-emergence of CHIKV has also resulted in numerous outbreaks in several countries in the eastern hemisphere, with a threat to further expand in the near future. However, there is no vaccine against CHIKV infection licensed for human use, and therapy for CHIKV infection is still mainly limited to supportive care as antiviral agents are yet in different stages of testing or development. In this review we explore the different perspectives for chikungunya treatment and the effectiveness of these treatment regimens and discuss the scope for future directions.

  19. Disturbance In Dry Coastal Dunes Promotes Diversity Of Plants And Arthropods

    DEFF Research Database (Denmark)

    Brunbjerg, Ane Kirstine; Jørgensen, Gorm Pilgaard; Nielsen, Kristian Mandsberg;

    2015-01-01

    Naturally disturbed coastal dunes have become strongly reduced during the last century due to the cessation of grazing by domestic herbivores, dune stabilization initiatives, and increasing nitrogen deposition, all promoting encroachment by grasses, shrubs and woody plants. We assessed the effects...... of three disturbance types (burning, trampling and blowouts) on plant and arthropod species richness and composition in dry coastal dunes in Jutland, Denmark. Environmental variables, plant presence–absence and arthropod abundance were measured in 150 1 × 2 m plots along transects in blowouts, burned areas......, trampled paths and their paired controls. We used Nonmetric Multidimensional Scaling (NMDS) ordination to assess differences in species composition of disturbed areas and controls. Ordination scores were used as response variables in Linear Mixed Effect (LME) models to test for the effects of disturbances...

  20. Haematophagous arthropod saliva and host defense system: a tale of tear and blood

    Directory of Open Access Journals (Sweden)

    Andrade Bruno B.

    2005-01-01

    Full Text Available The saliva from blood-feeding arthropod vectors is enriched with molecules that display diverse functions that mediate a successful blood meal. They function not only as weapons against host's haemostatic, inflammatory and immune responses but also as important tools to pathogen establishment. Parasites, virus and bacteria taking advantage of vectors' armament have adapted to facilitate their entry in the host. Today, many salivary molecules have been identified and characterized as new targets to the development of future vaccines. Here we focus on current information on vector's saliva and the molecules responsible to modify host's hemostasis and immune response, also regarding their role in disease transmission.

  1. Using the Ferret as an Animal Model for Investigating Influenza Antiviral Effectiveness.

    Science.gov (United States)

    Oh, Ding Y; Hurt, Aeron C

    2016-01-01

    The concern of the emergence of a pandemic influenza virus has sparked an increased effort toward the development and testing of novel influenza antivirals. Central to this is the animal model of influenza infection, which has played an important role in understanding treatment effectiveness and the effect of antivirals on host immune responses. Among the different animal models of influenza, ferrets can be considered the most suitable for antiviral studies as they display most of the human-like symptoms following influenza infections, they can be infected with human influenza virus without prior viral adaptation and have the ability to transmit influenza virus efficiently between one another. However, an accurate assessment of the effectiveness of an antiviral treatment in ferrets is dependent on three major experimental considerations encompassing firstly, the volume and titer of virus, and the route of viral inoculation. Secondly, the route and dose of drug administration, and lastly, the different methods used to assess clinical symptoms, viral shedding kinetics and host immune responses in the ferrets. A good understanding of these areas is necessary to achieve data that can accurately inform the human use of influenza antivirals. In this review, we discuss the current progress and the challenges faced in these three major areas when using the ferret model to measure influenza antiviral effectiveness. PMID:26870031

  2. Using the ferret as an animal model for investigating influenza antiviral effectiveness

    Directory of Open Access Journals (Sweden)

    Ding Yuan Oh

    2016-02-01

    Full Text Available The concern of the emergence of a pandemic influenza virus has sparked an increased effort towards the development and testing of novel influenza antivirals. Central to this is the animal model of influenza infection, which has played an important role in understanding treatment effectiveness and the effect of antivirals on host immune responses. Among the different animal models of influenza, ferrets can be considered the most suitable for antiviral studies as they display most of the human-like symptoms following influenza infections, they can be infected with human influenza virus without prior viral adaptation and have the ability to transmit influenza virus efficiently between one another. However, an accurate assessment of the effectiveness of an antiviral treatment in ferrets is dependent on three major experimental considerations encompassing firstly, the volume and titre of virus, and the route of viral inoculation. Secondly, the route and dose of drug administration, and lastly, the different methods used to assess clinical symptoms, viral shedding kinetics and host immune responses in the ferrets. A good understanding of these areas is necessary to achieve data that can accurately inform the human use of influenza antivirals. In this review, we discuss the current progress and the challenges faced in these three major areas when using the ferret model to measure influenza antiviral effectiveness.

  3. Simultaneous quantitation of serum HBV DNA and HBeAg can distinguish between slow and fast viral responses to antiviral therapy in patients with chronic hepatitis B A quantificação simultânea do DNA VHB e do AgHBe séricos podem distinguir entre resposta viral lenta e rápida à terapêutica anti-viral em pacientes com hepatite crônica B

    Directory of Open Access Journals (Sweden)

    Luiz Caetano da Silva

    2009-10-01

    Full Text Available BACKGROUND: The quantitation of serum HBeAg is not commonly used to monitor viral response to therapy in chronic hepatitis B. METHODS: In this study, 21 patients receiving varying therapies were followed and their viral response monitored by concomitant viral load and HBeAg quantitation in order to study the meaning and the kinetics of both parameters. RESULTS: It was possible to distinguish between three different patterns of viral response. The first was characterized by a simultaneous decrease in serum HBV DNA and HBeAg. The second pattern was characterized by a decrease in serum HBeAg but persistent detection of HBV DNA. The third pattern was characterized by undetectable HBV DNA with persistent HBeAg positivity, which points to a non-response (Pattern III-B except when HBeAg levels showed a slow but steady drop, characterizing a "slow responder" patient (Pattern III-A. CONCLUSIONS: The first pattern is compatible with a viral response. A long-term HBeAg seropositivity with a slow and persistent decrease (Pattern III-A is also compatible with a viral response and calls for a prolongation of anti-viral treatment.INTRODUÇÃO: A quantificação do AgHBe sérico não é habitualmente utilizada para monitorizar a resposta viral ao tratamento da hepatite crônica B. MÉTODOS: Neste estudo, 21 pacientes sob tratamento com diferentes terapias foram acompanhados e a resposta viral monitorizada pela quantificação concomitante da carga viral e do AgHBe a fim de investigar o significado e a cinética de ambos os parâmetros. RESULTADOS: Distinguiram-se três diferentes padrões de resposta viral. O primeiro caracterizou-se pela redução simultânea do HBV DNA e AgHBe séricos. O segundo padrão caracterizou-se por uma redução do AgHBe porém com detecção persistente do HBV DNA. O terceiro padrão caracterizou-se por HBV DNA indetectável com positividade persistente do AgHBe, sugerindo ausência de resposta (Padrão III-B, exceto quando os n

  4. Repeated Raking of Pine Plantations Alters Soil Arthropod Communities

    OpenAIRE

    Holly K. Ober; Lucas W. DeGroote

    2014-01-01

    Terrestrial arthropods in forests are engaged in vital ecosystem functions that ultimately help maintain soil productivity. Repeated disturbance can cause abrupt and irreversible changes in arthropod community composition and thereby alter trophic interactions among soil fauna. An increasingly popular means of generating income from pine plantations in the Southeastern U.S. is annual raking to collect pine litter. We raked litter once per year for three consecutive years in the pine plantatio...

  5. The seasonal variation of arthropods living on forest soil at different altitudes in fir (Abies nordmanniana subsp. bornmulleriana ecosystem in Bolu-Aladağ

    Directory of Open Access Journals (Sweden)

    Ahmet Duyar

    2016-07-01

    Full Text Available In the forest ecosystems, soil arthropods (Arthropoda, as primary and secondary consumers, have a significant role in litter decay and decomposition processes. The abundance, diversity and community structure of arthropods in soil ecosystem; give rapid response to change of site characteristics. The current study was aimed to determine of seasonal variation of soil arthropods on forest floor at different altitudes in Uludağ Fir (Abies nordmanniana subsp. bornmulleriana Mattf. ecosystem which is an important forest tree species in Turkey. The study was conducted in pure fir stands at 1200-1600 m altitudes (4 elevation gradients in Aladağ, Bolu. The sampling was carried out for each winter, spring, summer and autumn seasons. The samples were collected from forest floor by pitfall traps. Variations of abundance and diversity of arthropods were evaluated according to seasons and altitudes. The distributions in trophic levels and biological diversity of arthropods were also determined. During the study, the maximum abundance of arthropods was 7576 individuals/m² in summer among seasons, and was 7854 individuals/m² at 1200 m altitude. Shannon-Wiener Index (H′ and Species Richness (S′ values were detected in the pitfall traps (H′= 2.22; S′= 22.

  6. Antiviral Effect of Agaricomycetes Mushrooms (Review).

    Science.gov (United States)

    Teplyakova, Tamara V; Kosogova, Tatiana A

    2016-01-01

    This review presents data on the studied antiviral activities of Agaricomycetes mushrooms against the herpes, West Nile, influenza, human immunodeficiency, and hepatitis viruses, as well as orthopoxviruses, including the variola virus. Polysaccharides and other compounds (e.g., proteins, glycoproteins, terpenoids, melanins, nucleosides) exhibit antiviral activity against many viruses that are pathogenic in humans. Effective strains isolated from wild mushrooms in culture represent promising objects for the development of biotechnological drugs, including ones possessing antiviral activity. The data on antitumor and antiviral activities of compounds from the same mushroom species indicate the correlation of these properties. With regard to this connection, preparations of Basidiomycetes may have prophylactic value in preventing cancers with a viral etiology. PMID:27649599

  7. Evaluation of Antiviral Compounds Against Avian Influenza

    OpenAIRE

    Call, Evan W.

    1991-01-01

    Tests in vitro for antiviral activity against avian influenza viruses, A/Turkey/Sanpete/85 (H6N8) and A/Turkey/Sanpete/86 (H10N9), isolated in Sanpete County, Utah, utilized known antiviral agents, amantadine•HCl (adamantanamine hydrochloride) and ribavirin (1-β-D ribofuranosyl-1,2,4-triazole-3-carboxamide). The testing involved evaluation of seven drug concentrations. Maximum tolerated dose, minimum inhibitory concentration and therapeutic indexes were determined for each drug used. Both dru...

  8. Vaccines and Antiviral Drugs in Pandemic Preparedness

    OpenAIRE

    Arnold S. Monto

    2006-01-01

    While measures such as closing schools and social distancing may slow the effects of pandemic influenza, only vaccines and antiviral drugs are clearly efficacious in preventing infection or treating illness. Unless the pandemic strain closely resembles one already recognized, vaccine will not be available early. However, studies can be conducted beforehand to address questions concerning vaccine dose, frequency of inoculation, and need for adjuvants. In contrast, antiviral drugs, particularly...

  9. Iron metabolism in chronic hepatitis C patients on antiviral treatment

    Directory of Open Access Journals (Sweden)

    K. V. Zhdanov

    2009-01-01

    Full Text Available Purpose of the present research studying dynamics of the parameters describing a metabolism of iron at chronic hepatitis С patients on a combined antiviral therapy peg-interferon-2а and ribavirin. Has served 50 patients chronic hepatitis C (anti-HCV “+”, РНК HCV “+”, 1b genotype in the age from 18 till 59 years, on the average 33±1,5years, at various stages of disease and stages of monitoring antiviral treatments. To patients the parameters describing a metabolism of iron (serum iron, transferrin, ferritin, haptoglobin, ceruplasmin, total iron binding capacity, transferrin saturation by iron were defined. The sustain virology response (SVR was estimated - definition RNA HCV in half a year after end of treatment (72 week. It was carried out liver biopsy with the subsequent estimation of a degree of inflammatory activity and fibrosis on system METAVIR. Therapy peg-interferon-2а and ribavirin was accompanied by decrease serum iron, transferrin, ferritin, ceruplasmin, haptoglobin, transferrin saturation by iron irrespective of the answer to treatment. Thus, SVR directly correlated with higher level of iron and ceruplasmin of blood before therapy, on its background and during supervision. Normalization of biochemical activity chronic hepatitis C and positive morphological dynamics correspond with the parameters describing changes in a metabolism of iron at its patients, possibly, were compensatory-adaptive and to some extent endogen antiviral reaction of an organism of the person on HCV - infection. 

  10. The role of ecological infrastructure on beneficial arthropods in vineyards

    Directory of Open Access Journals (Sweden)

    Gabrijela Kuštera

    2016-03-01

    Full Text Available Weeds and non-cultivated plants have a great impact on abundance and diversity of beneficial arthropods in agriculture. The main aim of this work was to study the influence of the ecological infrastructure (meadows and weedy margins on the arthropod composition in vineyard surrounding landscape. Research was carried out from May to October during three years. Sampling took place in the ecological infrastructure of three differently managed vineyards (organic, integrated and extensive. Three zones were chosen in each vineyard (3 m, 10 m, and 30 m from the edge of the vineyard. Samples were taken using a standardised sweep net method. In total, we captured 6032 spiders and 1309 insects belonging to 4 orders and 10 families. Arthropod fauna was numerically dominated by Aranea (82.1%; among insects, Coleoptera was the most abundant taxonomic group (10.6%; Neuroptera showed the lowest value (0.88%. Significant differences were found between sites and zones. Organic vineyard showed the highest abundance of arthropods (92.41% were spiders and in the integrated vineyard there was a 23% of insects. Both the highest abundance of arthropods and the highest Shannon Index value (2.46 was found 3 m away from the edge of the vineyard. Results showed that spiders were the dominant arthropods and ladybugs the dominant insects. Weedy strips near the edge of the vineyard contained a high number of insects and spiders. Our results support the importance of weedy margins in enhancing the population of arthropods as well as in biodiversity promotion. Well-managed field margins could play important role in biological control of vineyard pests.

  11. Danger, diversity and priming in innate antiviral immunity.

    Science.gov (United States)

    Collins, Susan E; Mossman, Karen L

    2014-10-01

    The prototypic response to viral infection involves the recognition of pathogen-associated molecular patterns (PAMPs) by pattern recognition receptors (PRRs), leading to the activation of transcription factors such as IRF3 and NFkB and production of type 1 IFN. While this response can lead to the induction of hundreds of IFN-stimulated genes (ISGs) and recruitment and activation of immune cells, such a comprehensive response is likely inappropriate for routine low level virus exposure. Moreover, viruses have evolved a plethora of immune evasion strategies to subvert antiviral signalling. There is emerging evidence that cells have developed very sensitive methods of detecting not only specific viral PAMPS, but also more general danger or stress signals associated with viral entry and replication. Such stress-induced cellular responses likely serve to prime cells to respond to further PAMP stimulation or allow for a rapid and localized intracellular response independent of IFN production and its potential immune sequelae. This review discusses diversity in innate antiviral players and pathways, the role of "danger" sensing, and how alternative pathways, such as the IFN-independent pathway, may serve to prime cells for further pathogen attack.

  12. Containing pandemic influenza with antiviral agents.

    Science.gov (United States)

    Longini, Ira M; Halloran, M Elizabeth; Nizam, Azhar; Yang, Yang

    2004-04-01

    For the first wave of pandemic influenza or a bioterrorist influenza attack, antiviral agents would be one of the few options to contain the epidemic in the United States until adequate supplies of vaccine were available. The authors use stochastic epidemic simulations to investigate the effectiveness of targeted antiviral prophylaxis to contain influenza. In this strategy, close contacts of suspected index influenza cases take antiviral agents prophylactically. The authors compare targeted antiviral prophylaxis with vaccination strategies. They model an influenza pandemic or bioterrorist attack for an agent similar to influenza A virus (H2N2) that caused the Asian influenza pandemic of 1957-1958. In the absence of intervention, the model predicts an influenza illness attack rate of 33% of the population (95% confidence interval (CI): 30, 37) and an influenza death rate of 0.58 deaths/1,000 persons (95% Cl: 0.4, 0.8). With the use of targeted antiviral prophylaxis, if 80% of the exposed persons maintained prophylaxis for up to 8 weeks, the epidemic would be contained, and the model predicts a reduction to an illness attack rate of 2% (95% Cl: 0.2, 16) and a death rate of 0.04 deaths/1,000 persons (95% CI: 0.0003, 0.25). Such antiviral prophylaxis is nearly as effective as vaccinating 80% of the population. Vaccinating 80% of the children aged less than 19 years is almost as effective as vaccinating 80% of the population. Targeted antiviral prophylaxis has potential as an effective measure for containing influenza until adequate quantities of vaccine are available.

  13. The non-target impact of spinosyns on beneficial arthropods.

    Science.gov (United States)

    Biondi, Antonio; Mommaerts, Veerle; Smagghe, Guy; Viñuela, Elisa; Zappalà, Lucia; Desneux, Nicolas

    2012-12-01

    Spinosyn-based products, mostly spinosad, have been widely recommended by extension specialists and agribusiness companies; consequently, they have been used to control various pests in many different cropping systems. Following the worldwide adoption of spinosad-based products for integrated and organic farming, an increasing number of ecotoxicological studies have been published in the past 10 years. These studies are primarily related to the risk assessment of spinosad towards beneficial arthropods. This review takes into account recent data with the aim of (i) highlighting potentially adverse effects of spinosyns on beneficial arthropods (and hence on ecosystem services that they provide in agroecosystems), (ii) clarifying the range of methods used to address spinosyn side effects on biocontrol agents and pollinators in order to provide new insights for the development of more accurate bioassays, (iii) identifying pitfalls when analysing laboratory results to assess field risks and (iv) gaining increasing knowledge on side effects when using spinosad for integrated pest management (IPM) programmes and organic farming. For the first time, a thorough review of possible risks of spinosad and novel spinosyns (such as spinetoram) to beneficial arthropods (notably natural enemies and pollinators) is provided. The acute lethal effect and multiple sublethal effects have been identified in almost all arthropod groups studied. This review will help to optimise the future use of spinosad and new spinosyns in IPM programmes and for organic farming, notably by preventing the possible side effects of spinosyns on beneficial arthropods.

  14. Exoskeletons and economics: indoor arthropod diversity increases in affluent neighbourhoods.

    Science.gov (United States)

    Leong, Misha; Bertone, Matthew A; Bayless, Keith M; Dunn, Robert R; Trautwein, Michelle D

    2016-08-01

    In urban ecosystems, socioeconomics contribute to patterns of biodiversity. The 'luxury effect', in which wealthier neighbourhoods are more biologically diverse, has been observed for plants, birds, bats and lizards. Here, we used data from a survey of indoor arthropod diversity (defined throughout as family-level richness) from 50 urban houses and found that house size, surrounding vegetation, as well as mean neighbourhood income best predict the number of kinds of arthropods found indoors. Our finding, that homes in wealthier neighbourhoods host higher indoor arthropod diversity (consisting of primarily non-pest species), shows that the luxury effect can extend to the indoor environment. The effect of mean neighbourhood income on indoor arthropod diversity was particularly strong for individual houses that lacked high surrounding vegetation ground cover, suggesting that neighbourhood dynamics can compensate for local choices of homeowners. Our work suggests that the management of neighbourhoods and cities can have effects on biodiversity that can extend from trees and birds all the way to the arthropod life in bedrooms and basements.

  15. Epigeic soil arthropod abundance under different agricultural land uses

    Energy Technology Data Exchange (ETDEWEB)

    Perez-Bote, J. L.; Romero, A. J.

    2012-11-01

    The study of soil arthropods can provide valuable information how ecosystems respond to different management practices. The objective was to assess the total abundance, richness, and composition of epiedaphic arthropods in different agrosystems from southwestern Spain. Six sites with different agricultural uses were selected: olive grove, vineyards, olive grove with vineyards, wheat fields, fallows (150-300 m long), and abandoned vineyards. Crops were managed in extensive. Field margins were used as reference habitats. At the seven sites a total of 30 pitfall traps were arranged in a 10 × 3 grid. Traps were arranged to short (SD, 1 m), medium (MD, 6 m) and large (LD, 11 m) distance to the field margins in the middle of selected plots. Pitfall traps captured a total of 11,992 edaphic arthropods belonging to 11 different taxa. Soil fauna was numerically dominated by Formicidae (26.60%), Coleoptera (19.77%), and Aranae (16.76%). The higher number of soil arthropods were captured in the field margins followed by the abandoned vineyard. Significant differences were found between sites for total abundance, and zones. However, no significant differences for total abundance were found between months (April-July). Richness and diversity was highest in field margins and abandoned vineyards. Significant differences were found for these variables between sites. Our results suggest that agricultural intensification affects soil arthropods in Tierra de Barros area, a taxonomic group with an important role in the functioning of agricultural ecosystems. (Author) 32 refs.

  16. Exoskeletons and economics: indoor arthropod diversity increases in affluent neighbourhoods.

    Science.gov (United States)

    Leong, Misha; Bertone, Matthew A; Bayless, Keith M; Dunn, Robert R; Trautwein, Michelle D

    2016-08-01

    In urban ecosystems, socioeconomics contribute to patterns of biodiversity. The 'luxury effect', in which wealthier neighbourhoods are more biologically diverse, has been observed for plants, birds, bats and lizards. Here, we used data from a survey of indoor arthropod diversity (defined throughout as family-level richness) from 50 urban houses and found that house size, surrounding vegetation, as well as mean neighbourhood income best predict the number of kinds of arthropods found indoors. Our finding, that homes in wealthier neighbourhoods host higher indoor arthropod diversity (consisting of primarily non-pest species), shows that the luxury effect can extend to the indoor environment. The effect of mean neighbourhood income on indoor arthropod diversity was particularly strong for individual houses that lacked high surrounding vegetation ground cover, suggesting that neighbourhood dynamics can compensate for local choices of homeowners. Our work suggests that the management of neighbourhoods and cities can have effects on biodiversity that can extend from trees and birds all the way to the arthropod life in bedrooms and basements. PMID:27484644

  17. The occurrence of arthropods in processed rice products in Malaysia

    Institute of Scientific and Technical Information of China (English)

    Mariana A; Heah SK; Wong AL; Ho TM

    2010-01-01

    Objective:To determine distribution of arthropods in processed rice products such as rice flour and rice cereal-based infant food. Methods: Random samples of rice flour and rice cereal-based infant food purchased from commercial outlets were examined for the presence of arthropods using a modified Berlese Tullgren Funnel Method. Mites were mounted prior to identification and weevils were directly identified. Results: For non-expired products, infestation was found in 6.7%of rice flour and none was found in rice cereal-based infant food samples. The arthropods found in the flour samples were Cheyletus spp., Suidasia pontifica (S. pontifica), Tarsonemus spp., Tyrophagus putrescentiae (T. putrescentiae), Sitophilus granarius (S. granarius) and Sitophilus oryzae (S. oryzae). Others which cannot be identified were Oribatid and Prostigmatid mites. The most common mites in rice flour were Tarsonemus spp. (69.1%), followed by S. pontifica (18.2%). For expired products, only one sample of rice cereal-based infant food was infested and the infestation was by mites of the family Tydeidae. Conclusions:This study demonstrates the presence of 4 allergenic species of S. pontifica, T. putrescentiae, S. granarius and S. oryzae in rice flour. These arthropods can contribute to the incidence of anaphylaxis upon consumption by atopic individuals. There was no infestation of arthropods in rice cereal-based infant food surveyed except for an expired product in a moderate rusty tin container.

  18. Exoskeletons and economics: indoor arthropod diversity increases in affluent neighbourhoods

    Science.gov (United States)

    Bertone, Matthew A.; Bayless, Keith M.; Dunn, Robert R.; Trautwein, Michelle D.

    2016-01-01

    In urban ecosystems, socioeconomics contribute to patterns of biodiversity. The ‘luxury effect’, in which wealthier neighbourhoods are more biologically diverse, has been observed for plants, birds, bats and lizards. Here, we used data from a survey of indoor arthropod diversity (defined throughout as family-level richness) from 50 urban houses and found that house size, surrounding vegetation, as well as mean neighbourhood income best predict the number of kinds of arthropods found indoors. Our finding, that homes in wealthier neighbourhoods host higher indoor arthropod diversity (consisting of primarily non-pest species), shows that the luxury effect can extend to the indoor environment. The effect of mean neighbourhood income on indoor arthropod diversity was particularly strong for individual houses that lacked high surrounding vegetation ground cover, suggesting that neighbourhood dynamics can compensate for local choices of homeowners. Our work suggests that the management of neighbourhoods and cities can have effects on biodiversity that can extend from trees and birds all the way to the arthropod life in bedrooms and basements. PMID:27484644

  19. Inbreeding and the evolution of sociality in arthropods

    Science.gov (United States)

    Tabadkani, Seyed Mohammad; Nozari, Jamasb; Lihoreau, Mathieu

    2012-10-01

    Animals have evolved strategies to optimally balance costs and benefits of inbreeding. In social species, these adaptations can have a considerable impact on the structure, the organization, and the functioning of groups. Here, we consider how selection for inbreeding avoidance fashions the social behavior of arthropods, a phylum exhibiting an unparalleled richness of social lifestyles. We first examine life histories and parental investment patterns determining whether individuals should actively avoid or prefer inbreeding. Next, we illustrate the diversity of inbreeding avoidance mechanisms in arthropods, from the dispersal of individuals to the rejection of kin during mate choice and the production of unisexual broods by females. Then, we address the particular case of haplodiploid insects. Finally, we discuss how inbreeding may drive and shape the evolution of arthropods societies along two theoretical pathways.

  20. A fresh look at an antiviral helicase

    Institute of Scientific and Technical Information of China (English)

    Leonid Gitlin; Marco Colonna

    2007-01-01

    @@ In order to survive,all organlsms must guard against viral infections.Recognition of viruses is accomplished via multiple sensors.Many mammalian proteins can recognize viral products,such as double-stranded RNA(dsRNA),yet feW of them are known to induce interferon,the central antiviral messenger.Since interferon is indispensable for Successful antiviral defense [1],the interferon-inducing sensors have been of particular interest.However,a clear understanding of such sensors has been elusive,and the first well-established sensor family,the toll-like receptors (TLRs),was described relatively recently[2].Antiviral TLRS are positioned in the endosomes,where they report the appearance of viral genetic material(DNA,single-and double-stranded RNA).

  1. [Diversity and stability of arthropod assemblage in tea orchard].

    Science.gov (United States)

    Chen, Yigen; Xiong, Jinjun; Huang, Mingdu; Gu, Dejiu

    2004-05-01

    Two tea orchards, simplex tea orchard with weeds removed manually or by herbicides (STO) and complex tea orchard with the weed Hedyotis uncinella (CTO), each with an area of 0. 4 hm2, were established in 1995 in Yingde Hongxing Tea Plantation, Guangdong Province. The primary eigenvalues, species richness index (R), assemblage diversity index (H'), evenness index (J) and species concentration index (C) of arthropod assemblage were employed and compared to assess the efficacy of STO and CTO on the diversity and stabilityof arthropod assemblage. Stability indexes Ss/Si and Sn/Sp and variation coefficient of diversity index ds/dm were utilized as well. The results demonstrated that the R of arthropod assemblage in CTO ranged from 4 to 8, with the highest of 7.7403, while that in STO varied mainly between 4 to 6. The average R of arthropod assemblage in CTO was 5.4672 +/- 0.3483, higher than that in STO (4.8809 +/- 0.3175). The H' of arthropod in CTO (3.8535 +/- 0.1232) was higher, in contrast to the value in STO (3.4654 +/- 0.1856). The J in CTO was higher, while the species concentration index (C) was lower, in comparison to STO. The stability indexes Ss/Si and Sn/Sp of CTO were greater than those of STO, while the ds/dm in CTO (0.1107) was lower than that in STO (0.1855). All these indicated that the diversity of arthropod assemblage was better preserved in CTO, and the assemblage in CTO was more stable.

  2. DMPD: Toll-like receptors, RIG-I-like RNA helicases and the antiviral innate immuneresponse. [Dynamic Macrophage Pathway CSML Database

    Lifescience Database Archive (English)

    Full Text Available 17667934 Toll-like receptors, RIG-I-like RNA helicases and the antiviral innate imm...g) (.svg) (.html) (.csml) Show Toll-like receptors, RIG-I-like RNA helicases and the antiviral innate immune...response. PubmedID 17667934 Title Toll-like receptors, RIG-I-like RNA helicases and the anti

  3. Antiviral activity of constituents of Tamus communis.

    Science.gov (United States)

    Aquino, R; Conti, C; De Simone, F; Orsi, N; Pizza, C; Stein, M L

    1991-10-01

    The antiviral activity of the phenanthrene derivatives 1-6, of the spyrostane triglycosides dioscin (7) and gracillin (8), of the furostanol tetraglycosides methylprotodioscin (9), its (25S) epimer methylprotoneodioscin (10), and methylprotogracillin 11, have been tested towards two RNA viruses: vesicular stomatitis virus and human rhinovirus type 1B. All these products were extracted from the rizomes of Tamus communis L; compound 11 was isolated also from Asparagus cochinchinesis, together with pseudoprotodioscin (12), a 20 (22)-unsaturated furostanoside, which was also investigated for antiviral activity. The results were of some interest mainly for the phenanthrene derivatives. PMID:1667189

  4. Effect of Antiviral Therapy on Hepatitis C Virus Related Glomerulopathy

    Directory of Open Access Journals (Sweden)

    Abbas Ghulam

    2008-01-01

    Full Text Available To determine the efficacy of antiviral therapy in hepatitis C virus associated glome-rulopathy, we studied 30 patients with HCV-associated glomerulopathy at Sheikh Zayed Hospital, Lahore, Pakistan from June 2004 to February 2007. Membranoproliferative glomerulonephritis (MPGN was the commonest kidney lesion, being reported in 25/30 (83%, followed by membra-nous glomerulonephritis (MGN in 3/30 (10% and mesangioproliferative glomerulonephritis (MesGN in 2/30 (7%. Cryoglobulinaemia was positive in 8/20 (40% cases. Most common HCV genotype was 3a. All the patients received interferon alpha combined with ribavirin therapy for 6-12 months based on viral genotypes and doses were adjusted according to renal function. Anti-viral response was achieved in the form of aviremia at completion of 6 months treatment in 8/30 (26.6%, decreased transaminases levels from a mean of 96.4 ± 72.2 to 60.1 ± 44.3 IU/L, p= 0.005, 24-hour proteinuria decreased significantly from a mean of 4.8 g to 1.20 g, p= 0.001, and complement C3 and C4 concentrations returned to normal in those subjects who responded to treatment. The rate of relapse was 50%. We conclude that though the overall antiviral response of HCV was not high, there was a significant reduction in proteinuria suggesting indirectly an improvement in renal patho-logy. Further studies with large number of patients with follow-up renal biopsies are warranted.

  5. Canopy arthropods community within and among oak species in central Mexico

    OpenAIRE

    Efraín TOVAR-SANCHEZ

    2009-01-01

    Quercus rugosa and Q.laurina are species that presents a wide geographical distribution range in temperate forests of Mexico. Oak canopies contain a considerable portion of arthropod diversity and the arthropods fauna fulfill a wide variety of ecological roles. We examined the effect of oak species and seasonal changes on some community structure parameters (diversity, composition, similarity, biomass, rare species, and density of arthropod fauna) of canopy arthropods. In total, 40 oak ca...

  6. Antiviral Prophylaxis and Isolation for the Control of Pandemic Influenza

    OpenAIRE

    Qingxia Zhang; Dingcheng Wang

    2014-01-01

    Before effective vaccines become available, antiviral drugs are considered as the major control strategies for a pandemic influenza. However, perhaps such control strategies can be severely hindered by the low-efficacy of antiviral drugs. For this reason, using antiviral drugs and an isolation strategy is included in our study. A compartmental model that allows for imported exposed individuals and asymptomatic cases is used to evaluate the effectiveness of control strategies via antiviral pro...

  7. DMPD: Antiviral innate immunity pathways. [Dynamic Macrophage Pathway CSML Database

    Lifescience Database Archive (English)

    Full Text Available 16474426 Antiviral innate immunity pathways. Seth RB, Sun L, Chen ZJ. Cell Res. 200...6 Feb;16(2):141-7. (.png) (.svg) (.html) (.csml) Show Antiviral innate immunity pathways. PubmedID 16474426 ...Title Antiviral innate immunity pathways. Authors Seth RB, Sun L, Chen ZJ. Publication Cell Res. 2006 Feb;16

  8. Antiviral Prophylaxis and H1N1

    Centers for Disease Control (CDC) Podcasts

    2011-07-14

    Dr. Richard Pebody, a consultant epidemiologist at the Health Protection Agency in London, UK, discusses the use of antiviral post-exposure prophylaxis and pandemic H1N1.  Created: 7/14/2011 by National Center for Emerging Zoonotic and Infectious Diseases (NCEZID).   Date Released: 7/18/2011.

  9. Antiviral drug resistance of herpes simplex virus

    NARCIS (Netherlands)

    Stranska, Ruzena

    2004-01-01

    Infections with herpes simplex virus (HSV) usually have an asymptomatic or benign course. However, severe infections do occur, particularly in HIV/AIDS patients or transplant recipients, and may be life-threatening unless adequate antiviral therapy is given. Since its introduction in the early 1980

  10. Stable isotope methods in biological and ecological studies of arthropods

    NARCIS (Netherlands)

    Hood-Nowotny, R.C.; Knols, B.G.J.

    2007-01-01

    This is an eclectic review and analysis of contemporary and promising stable isotope methodologies to study the biology and ecology of arthropods. It is augmented with literature from other disciplines, indicative of the potential for knowledge transfer. It is demonstrated that stable isotopes can b

  11. Arthropods associated with medicinal plants in coastal South Carolina

    Institute of Scientific and Technical Information of China (English)

    ROLANDO LOPEZ; B. MERLE SHEPARD

    2007-01-01

    Arthropods were sampled from feverfew [Tanacetum parthenium (L.) SchultzBip], Echinaceapurpurea (L.) Moench, Echinaceapallida (Nutt.) Nutt., Valeriana officinalis L., and St. John's wort (Hypericum perforatum L.) during 1998-2001. In addition,arthropods were sampled on tansy (Tanacetum vulgare L.) from 2001-2004. In general,50-60 arthropod species where collected and identified among all of the medicinal plant species. Among the predators, Orius insidiosus (Say) (Hemiptera: Anthocoridae), Geocoris punctipes (Say) (Hemiptera: Lygaeidae) and spiders were most abundant from 1998-2004.The three-cornered alfalfa hopper, Spissistilus festinus (Say), was the most abundant herbivore found from 1998 to 2001. Orius insidiosus and G. punctipes were 3-4 times more abundant on T. parthenium than on any other medicinal plant species. Based on the numbers of predatory arthropods found on T. parthenium, this crop could be suitable as a companion or "banker" plant to attract and maintain populations of predators, especially O. insidiosus and G. punctipes. Whitefly nymphs attacked by predators with piercing/sucking mouthparts are easily identified using a microscope because of the general appearance of the carcass left by the predators. Thus, populations of predators on T. parthenium suppressed Bemisia tabaci populations on E. purpurea when these crops were planted as companion crops.

  12. Soluble proteins of chemical communication: an overview across arthropods

    Directory of Open Access Journals (Sweden)

    Paolo ePelosi

    2014-08-01

    Full Text Available Detection of chemical signals both in insects and in vertebrates is mediated by soluble proteins, highly concentrated in olfactory organs, which bind semiochemicals and activate, with still largely unknown mechanisms, specific chemoreceptors. The same proteins are often found in structures where pheromones are synthesised and released, where they likely perform a second role in solubilising and delivering chemical messengers in the environment.A single class of soluble polypeptides, called Odorant-Binding Proteins (OBPs is known in vertebrates, while two have been identified in insects, OBPs and CSPs (Chemosensory Proteins. Despite their common name, OBPs of vertebrates bear no structural similarity with those of insects. We observed that in arthropods OBPs are strictly limited to insects, while a few members of the CSP family have been found in crustacean and other arthropods, where however, based on their very limited numbers, a function in chemical communication seems unlikely.The question we address in this review is whether another class of soluble proteins may have been adopted by other arthropods to perform the role of OBPs and CSPs in insects. We propose that lipid-transporter proteins of the Niemann-Pick type C2 family could represent likely candidates and report the results of an analysis of their sequences in representative species of different arthropods.

  13. Injuries caused by arthropods: diagnostic and therapeutic approach in ER

    Directory of Open Access Journals (Sweden)

    Dutto Moreno

    2009-04-01

    Full Text Available Injuries caused by arthropods, primarily insects and arachnids, represent a significant source of lesions and allergies even in Italy, a country that has a negligible number of species with important toxicological characteristics from an emergency medicine point of view; unlike areas such as the Americas or Africa (including northern Africa where highly toxic autochthonous species are present, whose bite or sting can be life-threatening. Medical consultation both in hospital Emergency Rooms and general practitioners’ surgeries is markedly seasonal, occurring mainly in the spring and summer (April – September, consistent with arthropod activity. At the current time, in Italy, urgent acute arthropod-related injuries are rare and usually involve type I hypersensitivity, and in most cases they are localised lesions that cause discomfort. The aim of the article is to briefly summarise the species of insects and arachnids that are most frequently cause for medical consultation in Italy and to provide assistance in the diagnostic and therapeutic plan, focusing in particular on the importance of health education that in many acute arthropod-derived cases can play an important part in preventing reoccurrence.

  14. Horizontal Gene Transfer Contributes to the Evolution of Arthropod Herbivory.

    Science.gov (United States)

    Wybouw, Nicky; Pauchet, Yannick; Heckel, David G; Van Leeuwen, Thomas

    2016-01-01

    Within animals, evolutionary transition toward herbivory is severely limited by the hostile characteristics of plants. Arthropods have nonetheless counteracted many nutritional and defensive barriers imposed by plants and are currently considered as the most successful animal herbivores in terrestrial ecosystems. We gather a body of evidence showing that genomes of various plant feeding insects and mites possess genes whose presence can only be explained by horizontal gene transfer (HGT). HGT is the asexual transmission of genetic information between reproductively isolated species. Although HGT is known to have great adaptive significance in prokaryotes, its impact on eukaryotic evolution remains obscure. Here, we show that laterally transferred genes into arthropods underpin many adaptations to phytophagy, including efficient assimilation and detoxification of plant produced metabolites. Horizontally acquired genes and the traits they encode often functionally diversify within arthropod recipients, enabling the colonization of more host plant species and organs. We demonstrate that HGT can drive metazoan evolution by uncovering its prominent role in the adaptations of arthropods to exploit plants. PMID:27307274

  15. Consequences of cyclic vegetation management for arthropod survival : Simulation experiments

    NARCIS (Netherlands)

    Hinsch, Martin; Poethke, Hans-Joachim

    2007-01-01

    Many rare arthropod species occupy open grasslands. Mowing or grazing is needed to preserve the habitat for these species. Alternatively the vegetation cover in parts of the managed area can be periodically destroyed by ploughing or rototilling. Such treatment results in a dynamic mosaic of habitat

  16. Antiviral Activity of Metal-Containing Polymers—Organotin and Cisplatin-Like Polymers

    Directory of Open Access Journals (Sweden)

    Girish Barot

    2011-05-01

    Full Text Available Polymers containing platinum and to a lesser extent tin, have repeatedly demonstrated antitumor activity in vitro and in vivo against a variety of cell and tumor types. The mechanisms responsible for the antitumor activity include inducing a delay in cell proliferation and sister chromatid exchanges blocking tumor growth. As most DNA and some RNA viruses require, and even induce, infected cells to initiate DNA replication and subsequent cell division, compounds with antitumor activity will very likely also possess antiviral activity. This article examines the use of metal-containing polymers as a novel class of antivirals.

  17. Identification of a series of compounds with potent antiviral activity for the treatment of enterovirus infections.

    Science.gov (United States)

    MacLeod, Angus M; Mitchell, Dale R; Palmer, Nicholas J; Van de Poël, Hervé; Conrath, Katja; Andrews, Martin; Leyssen, Pieter; Neyts, Johan

    2013-07-11

    Rhinovirus (genus enterovirus) infections are responsible for many of the severe exacerbations of asthma and chronic obstructive pulmonary disease. Other members of the genus can cause life-threatening acute neurological infections. There is currently no antiviral drug approved for the treatment of such infections. We have identified a series of potent, broad-spectrum antiviral compounds that inhibit the replication of the human rhinovirus, Coxsackie virus, poliovirus, and enterovirus-71. The mechanism of action of the compounds has been established as inhibition of a lipid kinase, PI4KIIIβ. Inhibition of hepatitis C replication in a replicon assay correlated with enterovirus inhibition. PMID:24900715

  18. Antiviral effect of cationic compounds on bacteriophages

    Directory of Open Access Journals (Sweden)

    Mai Huong eChatain-Ly

    2013-03-01

    Full Text Available The antiviral activity of several cationic compounds - cetytrimethylammonium (CTAB, chitosan, nisin and lysozyme - was investigated on the bacteriophage c2 (DNA head and non-contractile tail infecting Lactococcus strains and the bacteriophage MS2 (F-specific RNA infecting E.coli. Firstly, these activities were evaluated in a phosphate buffer pH 7- 10 mM. The CTAB had a virucidal effect on the Lactococcus bacteriophages, but not on the MS2. After 1 min of contact with 0.125 mM CTAB, the c2 population was reduced from 6 log(pfu/mL to 1,5 log(pfu/mL and completely deactivated at 1 mM. On the contrary, chitosan inhibited the MS2 more than it did the bacteriophages c2. No antiviral effect was observed for the nisin or the lysozyme on bacteriophages after 1 min of treatment. A 1 and 2.5 log reduction was respectively observed for nisin and lysozyme when the treatment time increased (5 or 10 min. These results showed that the antiviral effect depended both on the virus and structure of the antimicrobial compounds. The antiviral activity of these compounds was also evaluated in different physico-chemical conditions and in complex matrices. The antiviral activity of CTAB was impaired in acid pH and with an increase of the ionic strength. These results might be explained by the electrostatic interactions between cationic compounds and negatively charged particles such as bacteriophages or other compounds in a matrix. Milk proved to be protective suggesting the components of food could interfere with antimicrobial compounds.

  19. Population-wide emergence of antiviral resistance during pandemic influenza.

    Directory of Open Access Journals (Sweden)

    Seyed M Moghadas

    Full Text Available BACKGROUND: The emergence of neuraminidase inhibitor resistance has raised concerns about the prudent use of antiviral drugs in response to the next influenza pandemic. While resistant strains may initially emerge with compromised viral fitness, mutations that largely compensate for this impaired fitness can arise. Understanding the extent to which these mutations affect the spread of disease in the population can have important implications for developing pandemic plans. METHODOLOGY/PRINCIPAL FINDINGS: By employing a deterministic mathematical model, we investigate possible scenarios for the emergence of population-wide resistance in the presence of antiviral drugs. The results show that if the treatment level (the fraction of clinical infections which receives treatment is maintained constant during the course of the outbreak, there is an optimal level that minimizes the final size of the pandemic. However, aggressive treatment above the optimal level can substantially promote the spread of highly transmissible resistant mutants and increase the total number of infections. We demonstrate that resistant outbreaks can occur more readily when the spread of disease is further delayed by applying other curtailing measures, even if treatment levels are kept modest. However, by changing treatment levels over the course of the pandemic, it is possible to reduce the final size of the pandemic below the minimum achieved at the optimal constant level. This reduction can occur with low treatment levels during the early stages of the pandemic, followed by a sharp increase in drug-use before the virus becomes widely spread. CONCLUSIONS/SIGNIFICANCE: Our findings suggest that an adaptive antiviral strategy with conservative initial treatment levels, followed by a timely increase in the scale of drug-use, can minimize the final size of a pandemic while preventing large outbreaks of resistant infections.

  20. Social stress in male mice impairs long-term antiviral immunity selectively in wounded subjects

    NARCIS (Netherlands)

    de Groot, J; Scholten, Jan W.; Koolhaas, JM; Boersma, Wim J.A.; Koolhaas, Jaap M.

    2002-01-01

    An important property of the antiviral immune response is its time-dependent character. Beginning with a few antigen-specific cells upon infection, it evolves to a stage where there is an abundance of antigen-specific cells and antibodies that are needed to clear the pathogen, and ends with circulat

  1. Phylogenetic relationships of the Wolbachia of nematodes and arthropods.

    Directory of Open Access Journals (Sweden)

    Katelyn Fenn

    2006-10-01

    Full Text Available Wolbachia are well known as bacterial symbionts of arthropods, where they are reproductive parasites, but have also been described from nematode hosts, where the symbiotic interaction has features of mutualism. The majority of arthropod Wolbachia belong to clades A and B, while nematode Wolbachia mostly belong to clades C and D, but these relationships have been based on analysis of a small number of genes. To investigate the evolution and relationships of Wolbachia symbionts we have sequenced over 70 kb of the genome of wOvo, a Wolbachia from the human-parasitic nematode Onchocerca volvulus, and compared the genes identified to orthologues in other sequenced Wolbachia genomes. In comparisons of conserved local synteny, we find that wBm, from the nematode Brugia malayi, and wMel, from Drosophila melanogaster, are more similar to each other than either is to wOvo. Phylogenetic analysis of the protein-coding and ribosomal RNA genes on the sequenced fragments supports reciprocal monophyly of nematode and arthropod Wolbachia. The nematode Wolbachia did not arise from within the A clade of arthropod Wolbachia, and the root of the Wolbachia clade lies between the nematode and arthropod symbionts. Using the wOvo sequence, we identified a lateral transfer event whereby segments of the Wolbachia genome were inserted into the Onchocerca nuclear genome. This event predated the separation of the human parasite O. volvulus from its cattle-parasitic sister species, O. ochengi. The long association between filarial nematodes and Wolbachia symbionts may permit more frequent genetic exchange between their genomes.

  2. Biodiversity and resilience of arthropod communities after fire disturbance in temperate forests.

    Science.gov (United States)

    Moretti, Marco; Duelli, Peter; Obrist, Martin K

    2006-08-01

    Changes in ecosystem functions following disturbances are of central concern in ecology and a challenge for ecologists is to understand the factors that affect the resilience of community structures and ecosystem functions. In many forest ecosystems, one such important natural disturbance is fire. The aim of this study was to understand the variation of resilience in six functional groups of invertebrates in response to different fire frequencies in southern Switzerland. We measured resilience by analysing arthropod species composition, abundance and diversity in plots where the elapsed time after single or repeated fires, as determined by dendrochronology, varied. We compared data from these plots with data from plots that had not burned recently and defined high resilience as the rapid recovery of the species composition to that prior to fire. Pooling all functional groups showed that they were more resilient to single fires than to repeated events, recovering 6-14 years after a single fire, but only 17-24 years after the last of several fires. Flying zoophagous and phytophagous arthropods were the most resilient groups. Pollinophagous and epigaeic zoophagous species showed intermediate resilience, while ground-litter saprophagous and saproxylophagous arthropods clearly displayed the lowest resilience to fire. Their species composition 17-24 years post-burn still differed markedly from that of the unburned control plots. Depending on the fire history of a forest plot, we found significant differences in the dominance hierarchy among invertebrate species. Any attempt to imitate natural disturbances, such as fire, through forest management must take into account the recovery times of biodiversity, including functional group composition, to ensure the conservation of multiple taxa and ecosystem functions in a sustainable manner. PMID:16804704

  3. Biodiversity and resilience of arthropod communities after fire disturbance in temperate forests.

    Science.gov (United States)

    Moretti, Marco; Duelli, Peter; Obrist, Martin K

    2006-08-01

    Changes in ecosystem functions following disturbances are of central concern in ecology and a challenge for ecologists is to understand the factors that affect the resilience of community structures and ecosystem functions. In many forest ecosystems, one such important natural disturbance is fire. The aim of this study was to understand the variation of resilience in six functional groups of invertebrates in response to different fire frequencies in southern Switzerland. We measured resilience by analysing arthropod species composition, abundance and diversity in plots where the elapsed time after single or repeated fires, as determined by dendrochronology, varied. We compared data from these plots with data from plots that had not burned recently and defined high resilience as the rapid recovery of the species composition to that prior to fire. Pooling all functional groups showed that they were more resilient to single fires than to repeated events, recovering 6-14 years after a single fire, but only 17-24 years after the last of several fires. Flying zoophagous and phytophagous arthropods were the most resilient groups. Pollinophagous and epigaeic zoophagous species showed intermediate resilience, while ground-litter saprophagous and saproxylophagous arthropods clearly displayed the lowest resilience to fire. Their species composition 17-24 years post-burn still differed markedly from that of the unburned control plots. Depending on the fire history of a forest plot, we found significant differences in the dominance hierarchy among invertebrate species. Any attempt to imitate natural disturbances, such as fire, through forest management must take into account the recovery times of biodiversity, including functional group composition, to ensure the conservation of multiple taxa and ecosystem functions in a sustainable manner.

  4. [Exposure degree of important non-target arthropods to Cry2Aa in Bt rice fields].

    Science.gov (United States)

    Zhang, Qing-Ling; Li, Yun-He; Hua, Hong-Xia; Yang, Chang-Ju; Wu, Hong-Jin; Peng, Yu-Fa

    2013-06-01

    Based on the principle of "risk = hazard x exposure", the selected representative nontarget organisms in the assessment of the potential effects of insect-resistant genetically modified (GM) crops on non-target arthropods in laboratory are generally the arthropod species highly exposed to the insecticidal proteins expressed by the GM crops in farmland ecosystem. In order to understand the exposure degree of the important arthropod species to Cry proteins in Bt rice fields, and to select the appropriate non-target arthropods in the risk assessment of insect-resistant GM crops, the enzyme-linked immunosorbent assay (ELISA) was conducted to measure the Cry2Aa protein concentration in the arthropods collected from the cry2Aa rice fields at different rice growth stages. The results showed that there was a significant difference in the Cry2Aa content protein concentration in different arthropod species. Some species did not contain Cry2Aa protein, while some species contained larger amounts of Cry2Aa protein. Relative to the arthropods colleted after rice anthesis, the arthropods colleted in rice anthesis contained relative higher concentrations of Cry2Aa protein, especially for the predacious arthropods. No Cry proteins were detected in parasitic arthropods. This study provided references for the laboratory assessment of the effects of GM rice on nontarget arthropods.

  5. Antiviral therapy effects upon hepatitis C cholestatic syndrome.

    Science.gov (United States)

    Vere, C C; Gofiţă, Eliza; Forţofoiu, C; Streba, Letiţia Adela Maria; Genunche, Amelia

    2007-01-01

    C in a rather small proportion. Under Interferon pegylate and Ribavirine treatment, low levels of direct bilirubine, cholesterol and enzymes were found. Hepatic cholestasis and, especially, the high serum values of gamma-glutamiltranspeptidase have a negative influence upon antiviral therapy, causing the low sustained virological response.

  6. Water balance in desert arthropods. Despite their small size, arthropods may be highly adapted for life in xeric conditions.

    Science.gov (United States)

    Edney, E B

    1967-05-26

    As judged by the number of species, or of individuals, arthropods are an extremely successful group of desert inhabitants. There is very great structural and physiological diversity within the group, and since adaptations to desert life open to one are not open to all. we should not expect to find the maximum possible development of adaptive features in any arthropod simply because it lives in a desert. Most adult insects fly; their larvae and all other arthropods do not, and their adaptations will differ accordingly. Desert beetles have very impermeable cuticles and tolerate high body temperatures, while desert cockroaches live below the sand. have more permeable cuticles, and absorb water vapor. There is probably no single respect in which all desert arthropods differ from insects of other environments. Perhaps a profitable way of viewing desert animals is to recognize that each is a whole organism with a specific collection of adaptations that must be consistent within themselves and which are associated with a specific mode of life and a specific evolutionary history. The arthropod organization is capable of producing highly efficient desert species. There is, however, a converse way of looking at the situation, Which is often neglected but which may be of general biological interest: does the evolution of adaptations to desert environments necessarily involve loss of viability in more mesic habitats? If so, then what are these disavantages- what, for example, is the disadvantage of a highly impermeable cuticle? In some cases the answer is clear: sandroaches need sand dunes to live in because they are morphologically and behaviorly specialized for this habitat. More often the answer is not obvious. PMID:6024185

  7. Exploiting Genetic Interference for Antiviral Therapy.

    Science.gov (United States)

    Tanner, Elizabeth J; Kirkegaard, Karla A; Weinberger, Leor S

    2016-05-01

    Rapidly evolving viruses are a major threat to human health. Such viruses are often highly pathogenic (e.g., influenza virus, HIV, Ebola virus) and routinely circumvent therapeutic intervention through mutational escape. Error-prone genome replication generates heterogeneous viral populations that rapidly adapt to new selection pressures, leading to resistance that emerges with treatment. However, population heterogeneity bears a cost: when multiple viral variants replicate within a cell, they can potentially interfere with each other, lowering viral fitness. This genetic interference can be exploited for antiviral strategies, either by taking advantage of a virus's inherent genetic diversity or through generating de novo interference by engineering a competing genome. Here, we discuss two such antiviral strategies, dominant drug targeting and therapeutic interfering particles. Both strategies harness the power of genetic interference to surmount two particularly vexing obstacles-the evolution of drug resistance and targeting therapy to high-risk populations-both of which impede treatment in resource-poor settings.

  8. An antiviral furanoquinone from Paulownia tomentosa Steud.

    Science.gov (United States)

    Kang, K H; Huh, H; Kim, B K; Lee, C K

    1999-11-01

    A methanol extract of the stem bark of Paulownia tomentosa showed antiviral activity against poliovirus types 1 and 3. Sequential liquid-liquid extraction with n-hexane, chloroform and water, and a silicagel column chromatography resulted in the purification of a compound. The compound was identified as methyl-5-hydroxy-dinaphthol[1,2-2',3']furan-7,12-dione-6-carbox yla te on the basis of spectroscopic data. The component caused a significant reduction of viral cytopathic effect when it was subjected to a standard antiviral assay by using HeLa cells. The EC(50) of the compound against poliovirus type 1 strain Brunhilde, and type 3 strain Leon were 0.3 microg/mL and 0.6 microg/mL, respectively. PMID:10548761

  9. Antiviral and Immunostimulant Activities of Andrographis paniculata

    OpenAIRE

    Churiyah; Olivia Bunga Pongtuluran; Elrade Rofaani; Tarwadi,

    2015-01-01

    Andrographis paniculata (Burm. f.) Nees is a medicinal plant which was reported to have anti HIV, anti pathogenic bacteria and immunoregulatory activities. The research purpose was to investigate the activity of Andrographis paniculata ethanol extract as antiviral and immunostimulant. A. paniculata leaves oven-dried, then grinded and macerated with ethanol 90%, and the extract then analyzed using High Performance Liquid Chromatography (HPLC) to determine the content of active compounds androg...

  10. The treatment of influenza with antiviral drugs

    OpenAIRE

    Stiver, Grant

    2003-01-01

    Influenza vaccination with current inactivated vaccines homologous to the prevalent wild-type virus can reduce influenza illness in 75%–80% of healthy adults. Vaccine is recommended for all individuals with chronic underlying diseases and for those aged 65 years or older. Although influenza vaccination is still advocated for patients with blunted immunity, protection rates are not as high, running at 40% for frail institutionalized elderly people. The influenza antiviral agents amantadine or ...

  11. ANTIVIRAL POTENTIAL OF MEDICINAL PLANTS: AN OVERVIEW

    OpenAIRE

    Ruwali Pushpa; Rai Nishant; Kumar Navin; Gautam Pankaj

    2013-01-01

    The term ‘Antiviral agents’ has been defined in very broad terms as substances other than a virus or virus containing vaccine or specific antibody which can produce either a protective or therapeutic effect to the clear detectable advantage of the virus infected host. The herbal medicine has a long traditional use and the major advantage over other medicines is their wide therapeutic window with rare side effects. There are some disadvantages of synthetic drugs like narrow therapeutic window...

  12. Antiviral Drug Resistance: Mechanisms and Clinical Implications

    OpenAIRE

    Strasfeld, Lynne; Chou, Sunwen

    2010-01-01

    Antiviral drug resistance is an increasing concern in immunocompromised patient populations, where ongoing viral replication and prolonged drug exposure lead to the selection of resistant strains. Rapid diagnosis of resistance can be made by associating characteristic viral mutations with resistance to various drugs as determined by phenotypic assays. Management of drug resistance includes optimization of host factors and drug delivery, selection of alternative therapies based on knowledge of...

  13. Antiviral lead compounds from marine sponges

    KAUST Repository

    Sagar, Sunil

    2010-10-11

    Marine sponges are currently one of the richest sources of pharmacologically active compounds found in the marine environment. These bioactive molecules are often secondary metabolites, whose main function is to enable and/or modulate cellular communication and defense. They are usually produced by functional enzyme clusters in sponges and/or their associated symbiotic microorganisms. Natural product lead compounds from sponges have often been found to be promising pharmaceutical agents. Several of them have successfully been approved as antiviral agents for clinical use or have been advanced to the late stages of clinical trials. Most of these drugs are used for the treatment of human immunodeficiency virus (HIV) and herpes simplex virus (HSV). The most important antiviral lead of marine origin reported thus far is nucleoside Ara-A (vidarabine) isolated from sponge Tethya crypta. It inhibits viral DNA polymerase and DNA synthesis of herpes, vaccinica and varicella zoster viruses. However due to the discovery of new types of viruses and emergence of drug resistant strains, it is necessary to develop new antiviral lead compounds continuously. Several sponge derived antiviral lead compounds which are hopedto be developed as future drugs are discussed in this review. Supply problems are usually the major bottleneck to the development of these compounds as drugs during clinical trials. However advances in the field of metagenomics and high throughput microbial cultivation has raised the possibility that these techniques could lead to the cost-effective large scale production of such compounds. Perspectives on biotechnological methods with respect to marine drug development are also discussed. 2010 by the authors; licensee MDPI.

  14. Meeting report: 4th ISIRV antiviral group conference: Novel antiviral therapies for influenza and other respiratory viruses.

    Science.gov (United States)

    McKimm-Breschkin, Jennifer L; Fry, Alicia M

    2016-05-01

    The International Society for Influenza and other Respiratory Virus Diseases (isirv) held its 4th Antiviral Group Conference at the University of Texas on 2-4 June, 2015. With emerging resistance to the drugs currently licensed for treatment and prophylaxis of influenza viruses, primarily the neuraminidase inhibitor oseltamivir phosphate (Tamiflu) and the M2 inhibitors amantadine and rimantadine, and the lack of effective interventions against other respiratory viruses, the 3-day programme focused on the discovery and development of inhibitors of several virus targets and key host cell factors involved in virus replication or mediating the inflammatory response. Virus targets included the influenza haemagglutinin, neuraminidase and M2 proteins, and both the respiratory syncytial virus and influenza polymerases and nucleoproteins. Therapies for rhinoviruses and MERS and SARS coronaviruses were also discussed. With the emerging development of monoclonal antibodies as therapeutics, the potential implications of antibody-dependent enhancement of disease were also addressed. Topics covered all aspects from structural and molecular biology to preclinical and clinical studies. The importance of suitable clinical trial endpoints and regulatory issues were also discussed from the perspectives of both industry and government. This meeting summary provides an overview, not only for the conference participants, but also for those interested in the current status of antivirals for respiratory viruses. PMID:26872862

  15. Diurnal temperature variations affect development of a herbivorous arthropod pest and its predators.

    Science.gov (United States)

    Vangansbeke, Dominiek; Audenaert, Joachim; Nguyen, Duc Tung; Verhoeven, Ruth; Gobin, Bruno; Tirry, Luc; De Clercq, Patrick

    2015-01-01

    The impact of daily temperature variations on arthropod life history remains woefully understudied compared to the large body of research that has been carried out on the effects of constant temperatures. However, diurnal varying temperature regimes more commonly represent the environment in which most organisms thrive. Such varying temperature regimes have been demonstrated to substantially affect development and reproduction of ectothermic organisms, generally in accordance with Jensen's inequality. In the present study we evaluated the impact of temperature alternations at 4 amplitudes (DTR0, +5, +10 and +15°C) on the developmental rate of the predatory mites Phytoseiulus persimilis Athias-Henriot and Neoseiulus californicus McGregor (Acari: Phytoseiidae) and their natural prey, the two-spotted spider mite Tetranychus urticae Koch (Acari: Tetranychidae). We have modelled their developmental rates as a function of temperature using both linear and nonlinear models. Diurnally alternating temperatures resulted in a faster development in the lower temperature range as compared to their corresponding mean constant temperatures, whereas the opposite was observed in the higher temperature range. Our results indicate that Jensen's inequality does not suffice to fully explain the differences in developmental rates at constant and alternating temperatures, suggesting additional physiological responses play a role. It is concluded that diurnal temperature range should not be ignored and should be incorporated in predictive models on the phenology of arthropod pests and their natural enemies and their performance in biological control programmes. PMID:25874697

  16. Diurnal temperature variations affect development of a herbivorous arthropod pest and its predators.

    Directory of Open Access Journals (Sweden)

    Dominiek Vangansbeke

    Full Text Available The impact of daily temperature variations on arthropod life history remains woefully understudied compared to the large body of research that has been carried out on the effects of constant temperatures. However, diurnal varying temperature regimes more commonly represent the environment in which most organisms thrive. Such varying temperature regimes have been demonstrated to substantially affect development and reproduction of ectothermic organisms, generally in accordance with Jensen's inequality. In the present study we evaluated the impact of temperature alternations at 4 amplitudes (DTR0, +5, +10 and +15°C on the developmental rate of the predatory mites Phytoseiulus persimilis Athias-Henriot and Neoseiulus californicus McGregor (Acari: Phytoseiidae and their natural prey, the two-spotted spider mite Tetranychus urticae Koch (Acari: Tetranychidae. We have modelled their developmental rates as a function of temperature using both linear and nonlinear models. Diurnally alternating temperatures resulted in a faster development in the lower temperature range as compared to their corresponding mean constant temperatures, whereas the opposite was observed in the higher temperature range. Our results indicate that Jensen's inequality does not suffice to fully explain the differences in developmental rates at constant and alternating temperatures, suggesting additional physiological responses play a role. It is concluded that diurnal temperature range should not be ignored and should be incorporated in predictive models on the phenology of arthropod pests and their natural enemies and their performance in biological control programmes.

  17. Combined effects of arthropod herbivores and phytopathogens on plant performance

    DEFF Research Database (Denmark)

    Hauser, Thure Pavlo; Christensen, Stina; Heimes, Christine;

    2013-01-01

    1. Many plants are simultaneously attacked by arthropod herbivores and phytopathogens. These may affect each other directly and indirectly, enhancing or reducing the amount of plant resources they each consume. Ultimately, this may reduce or enhance plant performance relative to what should be ex....... However, as interactive impacts also differed among environments and parasite manipulation methods, this suggests that the ability of plants to compensate such losses may depend on environmental conditions and probably also overall infection load......., the patterns we found were related to plant traits and experimental conditions. 5. Our results suggest that immediate loss of resources from interactions between arthropod herbivores and pathogens is generally moderated by compensation to an extent where there are no interactive effects on plant performance...

  18. Survey of the arthropods on jojoba (Simmondsia chinensis)

    Energy Technology Data Exchange (ETDEWEB)

    Pinto, J.D.; Frommer, S.I.

    1980-02-01

    Simmondsia chinensis (jojoba), a plant native to southwestern North America, has become of economic interest due to the various industrial uses of the unique liquid wax found in its seeds. In a survey of arthropods associated with sylvatic jojoba in California and Arizona, we collected 106 species of insects and mites. Of these, 50 are phytophagous, 29 are parasitic, and 18 are predaceous. Most of the phytophagous species are also known to feed on plants other than jojoba; several of these are notorious generalists. The bionomics of the 4 commonest phytophagous species, Asphondylia n. sp. (Cecidomyiidae), Epinotia kasloana (Olethreutidae), Periploca n. sp. (Walshiidae), and Incisitermes fruticavus (Kalotermitidae) are summarized briefly. None of the phytophagous species were observed to cause extensive damage to sylvatic jojoba. The numerous parasitic and predaceous arthropods probably account for the natural control of many of them. These relationships should be kept in mind when planning future commercial plantations of jojoba.

  19. 抗病毒天然免疫通路中IRF-3调控新机制%Regulation of Interferon Regulatory Factor-3 in Antiviral Innate Immune Response

    Institute of Scientific and Technical Information of China (English)

    刘殿波; 钱远宇; 张七斤; 陈忠斌

    2009-01-01

    干扰素调节因子-3(interferon regulatory factor-3,IRF-3)是IRF家族中重要转录因子之一,在调控干扰素(interferon,IFN)基因表达和抗病毒天然免疫反应中具有重要作用.最新发现的MITA(mediator of IRF-3 activation,又称STING/ERIS)蛋白是宿主抗病毒天然免疫反应中的一种重要调节分子.病毒侵染时,MITA与IRF-3相互作用,特异性激活IRF-3,并募集TANK结合激酶1(TANK binding kinase 1,TBK1)与IFN通路中的线粒体抗病毒信号蛋白MAVS(mitochondrial anti-viral signaling protein)形成复合物,且MITA可被TBK1磷酸化,诱导Ⅰ型IFN及IFN刺激基因(interferon stimulate genes,ISG)的表达,诱发抗病毒天然免疫反应.同时还发现,泛素连接酶RNF5(ring finger protein 5)可对MITA发生泛素化修饰从而抑制其对IRF-3活化,实现对宿主抗病毒天然免疫反应负调节作用.本室研究发现,严重性急性呼吸系统综合症冠状病毒(severe acute respiratory syndrome coronavirus,SARS-CoV)和人类新型冠状病毒(human coronavirus NL63,HCoV-NL63)的木瓜样蛋白酶(papain-like protease,PLP)利用其特有的去泛素化酶(deubiquitinase,DUB)活性,通过宿主细胞泛素-蛋白酶体信号系统对IRF-3的泛素化等翻译后修饰进行调节,从而成为该种病毒逃逸机体抗病毒防御系统主要手段之一.

  20. Arthropod-Borne Diseases: The Camper's Uninvited Guests.

    Science.gov (United States)

    Juckett, Gregory

    2015-08-01

    Arthropod-borne diseases are a major problem whenever outdoor activities bring arthropods and people into contact. The arthropods discussed here include arachnids (ticks) and insects. Most arthropod bites and stings are minor, with the notable exception being bee-sting anaphylaxis. Ticks cause the most disease transmission. Key hard tick vectors include black-legged (Ixodes), dog (Dermacentor), and lone star (Amblyomma) ticks, which transmit Lyme and various rickettsial diseases. Insect repellents, permethrin sprays, and proper tick inspection reduce this risk significantly. Lyme disease and the milder southern-tick-associated rash illness (STARI) are characterized by the erythema migrans rash followed, in the case of Lyme disease, by early, disseminated, and late systemic symptoms. Treatment is with doxycycline or ceftriaxone. Indefinite treatment of "chronic Lyme disease" based on subjective symptoms is not beneficial. Rickettsial diseases include ehrlichiosis, anaplasmosis, and Rocky Mountain spotted fever, which are characterized by fever, headache, and possible rash and should be empirically treated with doxycycline while awaiting laboratory confirmation. Tularemia is a bacterial disease (Francisella) spread by ticks and rabbits and characterized by fever and adenopathy. Treatment is with gentamicin or streptomycin. Babesiosis is a protozoal disease, mimicking malaria, that causes a self-limited flu-like disease in healthy hosts but can be life threatening with immune compromise. Treatment is with atovaquone and azithromycin. Other tick-related conditions include viral diseases (Powassan, Colorado tick fever, heartland virus), tick-borne relapsing fever (Borrelia), and tick paralysis (toxin). Mosquitoes, lice, fleas, and mites are notable for their annoying bites but are increasingly significant disease vectors even in the United States.

  1. Epidemiology and control of malaria and other arthropod born diseases

    Directory of Open Access Journals (Sweden)

    F. J. López-Antuñano

    1992-01-01

    Full Text Available Malaria and other arthropod born diseases remain a serious public health problem affecting the lives and health of certain social groups when the two basic strategies to control fail due to : (1 the lack of effective chemoprophylaxis/chemotherapy or the rapid development of drug resistance of the infectious agents and (2 the ineffectiveness of pesticides or the arthropod vectors develop resistance to them. These situations enhances the need for the design and implementation of other alternatives for sustainable health programmes. The application of the epidemiological methods is essential not only for analyzing the relevant data for the understanding of the biological characteristics of the infectious agents, their reservoirs and vectors and the methods for their control, but also for the assessment of the human behaviour, the environmental, social and economic factors involved in disease transmission and the capacity of the health systems to implement interventions for both changes in human behaviour and environmental management to purpose guaranteed prevention and control of malaria and other arthropod born diseases with efficiency, efficacy and equity. This paper discuss the evolution of the malaria arthropod diseases programmes in the American Region and the perspectives for their integration into health promotion programs and emphasis is made in the need to establish solid basis in the decision-making process for the selection of intervention strategies to remove the risk factors determining the probability to get sick or die from ABDs. The implications of the general planning and the polices to be adopted in an area should be analyzed in the light of programme feasibility at the local level, in the multisectoral context specific social groups and taking in consideration the principles of stratification and equity

  2. Fossil calibrations for the arthropod Tree of Life

    OpenAIRE

    Wolfe, JM; Daley, A; Legg, DA; Edgecombe, GD

    2016-01-01

    Fossil age data and molecular sequences are increasingly combined to establish a timescale for the Tree of Life. Arthropods, as the most species-rich and morphologically disparate animal phylum, have received substantial attention, particularly with regard to questions such as the timing of habitat shifts (e.g. terrestrialisation), genome evolution (e.g. gene family duplication and functional evolution), origins of novel characters and behaviours (e.g. wings and flight, venom, silk), biogeogr...

  3. Genetic diversity in aspen and its relation to arthropod abundance.

    Science.gov (United States)

    Zhang, Chunxia; Vornam, Barbara; Volmer, Katharina; Prinz, Kathleen; Kleemann, Frauke; Köhler, Lars; Polle, Andrea; Finkeldey, Reiner

    2014-01-01

    The ecological consequences of biodiversity have become a prominent public issue. Little is known on the effect of genetic diversity on ecosystem services. Here, a diversity experiment was established with European and North American aspen (Populus tremula, P. tremuloides) planted in plots representing either a single deme only or combinations of two, four and eight demes. The goals of this study were to explore the complex inter- and intraspecific genetic diversity of aspen and to then relate three measures for diversity (deme diversity, genetic diversity determined as Shannon index or as expected heterozygosity) to arthropod abundance. Microsatellite and AFLP markers were used to analyze the genetic variation patterns within and between the aspen demes and deme mixtures. Large differences were observed regarding the genetic diversity within demes. An analysis of molecular variance revealed that most of the total genetic diversity was found within demes, but the genetic differentiation among demes was also high. The complex patterns of genetic diversity and differentiation resulted in large differences of the genetic variation within plots. The average diversity increased from plots with only one deme to plots with two, four, and eight demes, respectively and separated plots with and without American aspen. To test whether intra- and interspecific diversity impacts on ecosystem services, arthropod abundance was determined. Increasing genetic diversity of aspen was related to increasing abundance of arthropods. However, the relationship was mainly driven by the presence of American aspen suggesting that species identity overrode the effect of intraspecific variation of European aspen.

  4. Parallel evolution of the genetic code in arthropod mitochondrial genomes.

    Directory of Open Access Journals (Sweden)

    Federico Abascal

    2006-05-01

    Full Text Available The genetic code provides the translation table necessary to transform the information contained in DNA into the language of proteins. In this table, a correspondence between each codon and each amino acid is established: tRNA is the main adaptor that links the two. Although the genetic code is nearly universal, several variants of this code have been described in a wide range of nuclear and organellar systems, especially in metazoan mitochondria. These variants are generally found by searching for conserved positions that consistently code for a specific alternative amino acid in a new species. We have devised an accurate computational method to automate these comparisons, and have tested it with 626 metazoan mitochondrial genomes. Our results indicate that several arthropods have a new genetic code and translate the codon AGG as lysine instead of serine (as in the invertebrate mitochondrial genetic code or arginine (as in the standard genetic code. We have investigated the evolution of the genetic code in the arthropods and found several events of parallel evolution in which the AGG codon was reassigned between serine and lysine. Our analyses also revealed correlated evolution between the arthropod genetic codes and the tRNA-Lys/-Ser, which show specific point mutations at the anticodons. These rather simple mutations, together with a low usage of the AGG codon, might explain the recurrence of the AGG reassignments.

  5. Hematopoiesis and Hematopoietic Organs in Arthropods

    OpenAIRE

    Grigorian, Melina; Hartenstein, Volker

    2013-01-01

    Hemocytes (blood cells) are motile cells moving throughout the extracellular space and exist in all clades of the animal kingdom. Hemocytes play an important role in shaping the extracellular environment and in the immune response. Developmentally, hemocytes are closely related to the epithelial cells lining the vascular system (endothelia) and body cavity (mesothelia). In vertebrates and insects, common progenitors, called hemangioblasts, give rise to the endothelia and blood cells. In the a...

  6. Nanoanalysis of the arthropod neuro-toxins

    OpenAIRE

    Nakajima, Terumi

    2006-01-01

    Many kinds of venomous principles modulate physiological responses of mammalian signal transduction systems, on which they act selectively as enhancers, inhibitors or some other kind of effectors. These toxins become useful tools for physiological research. We have employed and characterized paralyzing toxins from the venom of spiders, insects and scorpions with a limited supply. We have developed rapid and sensitive mass spectrometric technology and applied for the identification of these to...

  7. HIV/HCV Antiviral Drug Interactions in the Era of Direct-acting Antivirals

    Science.gov (United States)

    Rice, Donald P.; Faragon, John J.; Banks, Sarah; Chirch, Lisa M.

    2016-01-01

    Abstract Therapy for human immunodeficiency virus (HIV) and chronic hepatitis C has evolved over the past decade, resulting in better control of infection and clinical outcomes; however, drug-drug interactions remain a significant hazard. Joint recommendations from the American Association for the Study of Liver Diseases and the Infectious Diseases Society of America regarding drug-drug interactions between HIV antiretroviral agents and direct-acting antiviral agents for treatment of hepatitis C virus (HCV) infection are reviewed here. This review is oriented to facilitate appropriate selection of an antiviral therapy regimen for HCV infection based on the choice of antiretroviral therapy being administered and, if necessary, switching antiretroviral regimens. PMID:27777891

  8. Small molecules with antiviral activity against the Ebola virus

    OpenAIRE

    Nadia Litterman; Christopher Lipinski; Sean Ekins

    2015-01-01

    The recent outbreak of the Ebola virus in West Africa has highlighted the clear shortage of broad-spectrum antiviral drugs for emerging viruses. There are numerous FDA approved drugs and other small molecules described in the literature that could be further evaluated for their potential as antiviral compounds. These molecules are in addition to the few new antivirals that have been tested in Ebola patients but were not originally developed against the Ebola virus, and may play an important r...

  9. Determining Mechanism of Action of Antivirals for Respiratory Illness

    Science.gov (United States)

    Rodriguez, Irma; Dobrovolny, Hana

    2015-03-01

    Viral infections in the respiratory tract are common in humans and can cause serious illness and death. Drug treatment is the principal line of protection against many of these illnesses and many compounds are tested as antivirals. Often the efficacy of these antivirals are determined before a mechanism of action is understood. We use mathematical models to represent the evolution of these diseases and establish which experiments can help determine the mechanism of action of antivirals.

  10. The i5K Initiative: advancing arthropod genomics for knowledge, human health, agriculture, and the environment.

    Science.gov (United States)

    2013-01-01

    Insects and their arthropod relatives including mites, spiders, and crustaceans play major roles in the world's terrestrial, aquatic, and marine ecosystems. Arthropods compete with humans for food and transmit devastating diseases. They also comprise the most diverse and successful branch of metazoan evolution, with millions of extant species. Here, we describe an international effort to guide arthropod genomic efforts, from species prioritization to methodology and informatics. The 5000 arthropod genomes initiative (i5K) community met formally in 2012 to discuss a roadmap for sequencing and analyzing 5000 high-priority arthropods and is continuing this effort via pilot projects, the development of standard operating procedures, and training of students and career scientists. With university, governmental, and industry support, the i5K Consortium aspires to deliver sequences and analytical tools for each of the arthropod branches and each of the species having beneficial and negative effects on humankind. PMID:23940263

  11. CEACAM1 induces B-cell survival and is essential for protective antiviral antibody production.

    Science.gov (United States)

    Khairnar, Vishal; Duhan, Vikas; Maney, Sathish Kumar; Honke, Nadine; Shaabani, Namir; Pandyra, Aleksandra A; Seifert, Marc; Pozdeev, Vitaly; Xu, Haifeng C; Sharma, Piyush; Baldin, Fabian; Marquardsen, Florian; Merches, Katja; Lang, Elisabeth; Kirschning, Carsten; Westendorf, Astrid M; Häussinger, Dieter; Lang, Florian; Dittmer, Ulf; Küppers, Ralf; Recher, Mike; Hardt, Cornelia; Scheffrahn, Inka; Beauchemin, Nicole; Göthert, Joachim R; Singer, Bernhard B; Lang, Philipp A; Lang, Karl S

    2015-01-01

    B cells are essential for antiviral immune defence because they produce neutralizing antibodies, present antigen and maintain the lymphoid architecture. Here we show that intrinsic signalling of CEACAM1 is essential for generating efficient B-cell responses. Although CEACAM1 exerts limited influence on the proliferation of B cells, expression of CEACAM1 induces survival of proliferating B cells via the BTK/Syk/NF-κB-axis. The absence of this signalling cascade in naive Ceacam1(-/-) mice limits the survival of B cells. During systemic infection with cytopathic vesicular stomatitis virus, Ceacam1(-/-) mice can barely induce neutralizing antibody responses and die early after infection. We find, therefore, that CEACAM1 is a crucial regulator of B-cell survival, influencing B-cell numbers and protective antiviral antibody responses. PMID:25692415

  12. Antiviral therapy of decompensated hepatitis B virus-related cirrhosis

    Institute of Scientific and Technical Information of China (English)

    CHEN Guang-cheng; YU Tao; HUANG Kai-hong; CHEN Qi-kui

    2012-01-01

    Objective To review the development,mechanism,necessity and limitation of antiviral therapy in decompensated hepatitis B virus-related cirrhosis.Data sources Most information was pulled from a literature search (Pubmed 2000 to 2011) using the keywords of antiviral and decompensated hepatitis B virus-related cirrhosis.Relevant book chapters were also reviewed.Study selection Well-controlled,prospective landmark studies and review articles on antiviral therapy in decompesated hepatitis B virus-related cirrhosis were selected.Results Specific antiviral agents not only control viral replication,which permits liver transplantation,but also improve liver function so significantly that patients could be removed from the transplant waiting list.However,the emergence of drug-resistant mutants can result in treatment failure.Combination therapy is a save-strategy in drug-resistant.Conclusions Although the treatment of end-stage liver disease is still a challenge worldwide,antiviral therapy has altered the natural history of hepatitis B patients with decompensated cirrhosis.The approval of the new generation of antivirals is opening new perspectives for finding the optimal antiviral treatment for patients with decompensated cirrhosis and preventing antiviral resistance.A combination of antivirals may be one of the future strategies for fulfilling these goals.

  13. Plant diversity impacts decomposition and herbivory via changes in aboveground arthropods

    OpenAIRE

    Anne Ebeling; Meyer, Sebastian T.; Maike Abbas; Nico Eisenhauer; Helmut Hillebrand; Markus Lange; Christoph Scherber; Anja Vogel; Alexandra Weigelt; Weisser, Wolfgang W.

    2014-01-01

    Loss of plant diversity influences essential ecosystem processes as aboveground productivity, and can have cascading effects on the arthropod communities in adjacent trophic levels. However, few studies have examined how those changes in arthropod communities can have additional impacts on ecosystem processes caused by them (e.g. pollination, bioturbation, predation, decomposition, herbivory). Therefore, including arthropod effects in predictions of the impact of plant diversity loss on such ...

  14. RSS (http://www.iaees.org/publications/journals/arthropods/rss.xml

    Directory of Open Access Journals (Sweden)

    Arthropods (ISSN 2224-4255

    Full Text Available Arthropods ISSN 2224-4255 URL: http://www.iaees.org/publications/journals/arthropods/online-version.asp RSS: http://www.iaees.org/publications/journals/arthropods/rss.xml E-mail: arthropods@iaees.org Editor-in-Chief: WenJun Zhang Aims and Scope ARTHROPODS (ISSN 2224-4255 is an international journal devoted to the publication of articles on various aspects of arthropods, e.g., ecology, biogeography, systematics, biodiversity (species diversity, genetic diversity, et al., conservation, control, etc. The journal provides a forum for examining the importance of arthropods in biosphere (both terrestrial and marine ecosystems and human life in such fields as agriculture, forestry, fishery, environmental management and human health. The scope of Arthropods is wide and embraces all arthropods-insects, arachnids, crustaceans, centipedes, millipedes, and other arthropods. Articles/short communications on new taxa (species, genus, families, orders, etc. and new records of arthropods are particularly welcome. Authors can submit their works to the email box of this journal, arthropods@iaees.org. All manuscripts submitted to this journal must be previously unpublished and may not be considered for publication elsewhere at any time during review period of this journal. Authors are asked to read Author Guidelines before submitting manuscripts. In addition to free submissions from authors around the world, special issues are also accepted. The organizer of a special issue can collect submissions (yielded from a research project, a research group, etc. on a specific research topic, or submissions of a scientific conference for publication of special issue.

  15. Inhibition of HIV replication by pokeweed antiviral protein targeted to CD4+ cells by monoclonal antibodies

    Science.gov (United States)

    Zarling, Joyce M.; Moran, Patricia A.; Haffar, Omar; Sias, Joan; Richman, Douglas D.; Spina, Celsa A.; Myers, Dorothea E.; Kuebelbeck, Virginia; Ledbetter, Jeffrey A.; Uckun, Fatih M.

    1990-09-01

    FUNCTIONAL impairment and selective depletion of CD4+ T cells, the hallmark of AIDS, are at least partly caused by human immunodeficiency virus (HIV-1) type 1 binding to the CD4 molecule and infecting CD4+ cells1,2. It may, therefore, be of therapeutic value to target an antiviral agent to CD4+ cells to prevent infection and to inhibit HIV-1 production in patients' CD4+ cells which contain proviral DNA3,4. We report here that HIV-1 replication in normal primary CD4+ T cells can be inhibited by pokeweed antiviral protein, a plant protein of relative molecular mass 30,000 (ref. 5), which inhibits replication of certain plant RNA viruses6-8, and of herpes simplex virus, poliovirus and influenza virus9-11. Targeting pokeweed antiviral protein to CD4+ T cells by conjugating it to monoclonal antibodies reactive with CDS, CD7 or CD4 expressed on CD4+ cells, increased its anti-HIV potency up to 1,000-fold. HIV-1 replication is inhibited at picomolar concentrations of conjugates of pokeweed antiviral protein and monoclonal antibodies, which do not inhibit proliferation of normal CD4+ T cells or CD4-dependent responses. These conjugates inhibit HIV-1 protein synthesis and also strongly inhibit HIV-1 production in activated CD4+ T cells from infected patients.

  16. Genetic diversity of the hepatitis C virus: Impact and issues in the antiviral therapy

    Institute of Scientific and Technical Information of China (English)

    H Le Guillou-Guillemette; S Vallet; C Gaudy-Graffin; C Payan; A Pivert; A Goudeau; F Lunel-Fabiani

    2007-01-01

    The hepatitis C Virus (HCV) presents a high degree of genetic variability which is explained by the combination of a lack of proof reading by the RNA dependant RNA polymerase and a high level of viral replication. The resuiting genetic polymorphism defines a classification in clades, genotypes, subtypes, isolates and quasispecies.This diversity is known to reflect the range of responses to Interferon therapy. The genotype is one of the predictive parameters currently used to define the antiviral treatment strategy and the chance of therapeutic success. Studies have also reported the potential impact of the viral genetic polymorphism in the outcome of antiviral therapy in patients infected by the same HCV genotype. Both structural and non structural genomic regions of HCV have been suggested to be involved in the Interferon pathway and the resistance to antiviral therapy. In this review, we first detail the viral basis of HCV diversity.Then, the HCV genetic regions that may be implicated in resistance to therapy are described, with a focus on the structural region encoded by the E2 gene and the non-structural genes NS3, NS5A and NS5B. Both mechanisms of the Interferon resistance and of the new antiviral drugs are described in this review.

  17. Tannic acid modified silver nanoparticles show antiviral activity in herpes simplex virus type 2 infection.

    Directory of Open Access Journals (Sweden)

    Piotr Orlowski

    Full Text Available The interaction between silver nanoparticles and herpesviruses is attracting great interest due to their antiviral activity and possibility to use as microbicides for oral and anogenital herpes. In this work, we demonstrate that tannic acid modified silver nanoparticles sized 13 nm, 33 nm and 46 nm are capable of reducing HSV-2 infectivity both in vitro and in vivo. The antiviral activity of tannic acid modified silver nanoparticles was size-related, required direct interaction and blocked virus attachment, penetration and further spread. All tested tannic acid modified silver nanoparticles reduced both infection and inflammatory reaction in the mouse model of HSV-2 infection when used at infection or for a post-infection treatment. Smaller-sized nanoparticles induced production of cytokines and chemokines important for anti-viral response. The corresponding control buffers with tannic acid showed inferior antiviral effects in vitro and were ineffective in blocking in vivo infection. Our results show that tannic acid modified silver nanoparticles are good candidates for microbicides used in treatment of herpesvirus infections.

  18. Arthropods of the great indoors: characterizing diversity inside urban and suburban homes.

    Science.gov (United States)

    Bertone, Matthew A; Leong, Misha; Bayless, Keith M; Malow, Tara L F; Dunn, Robert R; Trautwein, Michelle D

    2016-01-01

    Although humans and arthropods have been living and evolving together for all of our history, we know very little about the arthropods we share our homes with apart from major pest groups. Here we surveyed, for the first time, the complete arthropod fauna of the indoor biome in 50 houses (located in and around Raleigh, North Carolina, USA). We discovered high diversity, with a conservative estimate range of 32-211 morphospecies, and 24-128 distinct arthropod families per house. The majority of this indoor diversity (73%) was made up of true flies (Diptera), spiders (Araneae), beetles (Coleoptera), and wasps and kin (Hymenoptera, especially ants: Formicidae). Much of the arthropod diversity within houses did not consist of synanthropic species, but instead included arthropods that were filtered from the surrounding landscape. As such, common pest species were found less frequently than benign species. Some of the most frequently found arthropods in houses, such as gall midges (Cecidomyiidae) and book lice (Liposcelididae), are unfamiliar to the general public despite their ubiquity. These findings present a new understanding of the diversity, prevalence, and distribution of the arthropods in our daily lives. Considering their impact as household pests, disease vectors, generators of allergens, and facilitators of the indoor microbiome, advancing our knowledge of the ecology and evolution of arthropods in homes has major economic and human health implications.

  19. Canopy arthropods community within and among oak species in central Mexico

    Institute of Scientific and Technical Information of China (English)

    Efraín TOVAR-SANCHEZ

    2009-01-01

    Quercus rugosa and Q.laurina are species that presents a wide geographical distribution range in temperate forests of Mexico. Oak canopies contain a considerable portion of arthropod diversity and the arthropods fauna fulfill a wide variety of ecological roles. We examined the effect of oak species and seasonal changes on some community structure parameters (diversity, composition, similarity, biomass, rare species, and density of arthropod fauna) of canopy arthropods. In total, 40 oak canopies were fogged during rainy and dry season. A total of 614 identified arthropod morphospecies were recognized belonging to 22 orders associated with tree canopies. A separation of host tree species during both seasons, suggesting a different community structure on host plants species was demonstrated by the principal component analyses (PCA), therefore, differences between oak species results in phenotypes that structure the composition of the arthropod community. Q.laurina registered the highest densities, diversity index and number of rare species in comparison with Q.rugosa. While arthropod biomass showed an inverse pattern. Trees more close to one another (spatial distance) register a more similar canopy arthropod fauna. This study suggests that the trees of Q.laurina could act as a center of biodiversity by the accumulation of arthropod fauna with a considerable number of rare species, which presents wide ecological roles or is involved in critical processes that maintain forest ecosystems[Current Zoology 55(2):132-144,2009].

  20. Arthropods of the great indoorssuburban homes:characterizing diversity inside urban and suburban homes

    OpenAIRE

    Bertone, Matthew A.; Leong, Misha; Bayless, Keith M.; Malow, Tara L.F.; Dunn, Robert Roberdeau; Trautwein, Michelle D.

    2016-01-01

    Although humans and arthropods have been living and evolving together for all of our history, we know very little about the arthropods we share our homes with apart from major pest groups. Here we surveyed, for the first time, the complete arthropod fauna of the indoor biome in 50 houses (located in and around Raleigh, North Carolina, USA). We discovered high diversity, with a conservative estimate range of 32–211 morphospecies, and 24–128 distinct arthropod families per house. The majority o...

  1. Arthropods of the great indoors: characterizing diversity inside urban and suburban homes.

    Science.gov (United States)

    Bertone, Matthew A; Leong, Misha; Bayless, Keith M; Malow, Tara L F; Dunn, Robert R; Trautwein, Michelle D

    2016-01-01

    Although humans and arthropods have been living and evolving together for all of our history, we know very little about the arthropods we share our homes with apart from major pest groups. Here we surveyed, for the first time, the complete arthropod fauna of the indoor biome in 50 houses (located in and around Raleigh, North Carolina, USA). We discovered high diversity, with a conservative estimate range of 32-211 morphospecies, and 24-128 distinct arthropod families per house. The majority of this indoor diversity (73%) was made up of true flies (Diptera), spiders (Araneae), beetles (Coleoptera), and wasps and kin (Hymenoptera, especially ants: Formicidae). Much of the arthropod diversity within houses did not consist of synanthropic species, but instead included arthropods that were filtered from the surrounding landscape. As such, common pest species were found less frequently than benign species. Some of the most frequently found arthropods in houses, such as gall midges (Cecidomyiidae) and book lice (Liposcelididae), are unfamiliar to the general public despite their ubiquity. These findings present a new understanding of the diversity, prevalence, and distribution of the arthropods in our daily lives. Considering their impact as household pests, disease vectors, generators of allergens, and facilitators of the indoor microbiome, advancing our knowledge of the ecology and evolution of arthropods in homes has major economic and human health implications. PMID:26819844

  2. Interplays between Soil-Borne Plant Viruses and RNA Silencing-Mediated Antiviral Defense in Roots

    Science.gov (United States)

    Andika, Ida Bagus; Kondo, Hideki; Sun, Liying

    2016-01-01

    Although the majority of plant viruses are transmitted by arthropod vectors and invade the host plants through the aerial parts, there is a considerable number of plant viruses that infect roots via soil-inhabiting vectors such as plasmodiophorids, chytrids, and nematodes. These soil-borne viruses belong to diverse families, and many of them cause serious diseases in major crop plants. Thus, roots are important organs for the life cycle of many viruses. Compared to shoots, roots have a distinct metabolism and particular physiological characteristics due to the differences in development, cell composition, gene expression patterns, and surrounding environmental conditions. RNA silencing is an important innate defense mechanism to combat virus infection in plants, but the specific information on the activities and molecular mechanism of RNA silencing-mediated viral defense in root tissue is still limited. In this review, we summarize and discuss the current knowledge regarding RNA silencing aspects of the interactions between soil-borne viruses and host plants. Overall, research evidence suggests that soil-borne viruses have evolved to adapt to the distinct mechanism of antiviral RNA silencing in roots.

  3. Impact of invasive Rosa rugosa on the arthropod fauna of Danish yellow dunes

    DEFF Research Database (Denmark)

    Pernille, Elleriis; Pedersen, Morten Lauge; Toft, Søren

    2015-01-01

    monospecific shrubbery rich in large flowers. We predicted faunal responses according to the changes in resource availability and environmental conditions promoted by this particular invasive plant: increased populations of flower-visiting insects and species of the phytophagous and detritivorous guilds......We compared the arthropod fauna of Rosa rugosa patches to the adjacent native yellow dune vegetation by pitfall trapping in the National Park Thy at the Danish North Sea coast. R. rugosa changes the vegetation from a dune grassland (dominated by Ammophila arenaria) poor in flowering plants to a low...... and diversity and increased dominance in the rose patches, due to reductions among xerotherm species. The results indicate that considerable faunistic impoverishment of thermophilic dune specialist species can be expected in the future if R. rugosa is allowed to continue its invasion across the dune habitat....

  4. Neuropsychiatric Effects of HIV Antiviral Medications.

    Science.gov (United States)

    Treisman, Glenn J; Soudry, Olivia

    2016-10-01

    The development of antiretroviral therapy (ART) has dramatically increased the lifespan of HIV patients but treatment is complicated by numerous adverse effects and toxicities. ART complications include neuropsychiatric, metabolic, gastrointestinal, cardiac, and numerous other toxicities, and clinicians often have to choose one toxicity over another to offer the best medication regimen for a patient. Some antiviral drugs cause significant neuropsychiatric complications, including depression, cognitive impairment, and sleep disturbance. Even in careful studies, it may be difficult to determine which effects are related to the virus, the immune system, or the treatment. Of the six currently marketed classes of antiviral drugs, the nucleoside reverse transcriptase inhibitors and the non-nucleoside reverse transcriptase inhibitors have been most commonly associated with neuropsychiatric complications. Within these classes, certain drugs are more likely to cause difficulty than others. We review the contention regarding the central nervous system (CNS) complications of efavirenz, as well as debate about the role of CNS penetration in drug effectiveness and toxicity. A thorough working knowledge of the neuropsychiatric consequences of ART allows clinicians to tailor treatment more successfully to individual patients as well as to identify ART more quickly as the source of a problem or symptom. PMID:27534750

  5. Antiviral and Immunostimulant Activities of Andrographis paniculata

    Directory of Open Access Journals (Sweden)

    Churiyah

    2015-04-01

    Full Text Available Andrographis paniculata (Burm. f. Nees is a medicinal plant which was reported to have anti HIV, anti pathogenic bacteria and immunoregulatory activities. The research purpose was to investigate the activity of Andrographis paniculata ethanol extract as antiviral and immunostimulant. A. paniculata leaves oven-dried, then grinded and macerated with ethanol 90%, and the extract then analyzed using High Performance Liquid Chromatography (HPLC to determine the content of active compounds andrographolide. The antiviral activity of the extract was determined by observing its ability on inhibiting virus load in A549 cells transfected with Simian Retro Virus (SRV by Real Time – Polymerase Chain Reaction (RT-PCR analysis. The immunostimulant activity of extract was determined by its ability to induce lymphocytes cell proliferation using 3-(4,5-dimethylthiazol-2-yl-2,5-diphenyltetrazolium bromide (MTT assay. Our result indicated that the A. paniculata ethanol extract inhibited the SRV virus titer similar to the positive control Lamivudine, and it was not toxic to the A459 cell line. Furthermore, low concentration (1 μg/mL of A. paniculata extract could stimulated lymphocyte cell proliferation about 38% compared to the control lymphocyte cell without any treatment.

  6. Exploiting Genetic Interference for Antiviral Therapy.

    Science.gov (United States)

    Tanner, Elizabeth J; Kirkegaard, Karla A; Weinberger, Leor S

    2016-05-01

    Rapidly evolving viruses are a major threat to human health. Such viruses are often highly pathogenic (e.g., influenza virus, HIV, Ebola virus) and routinely circumvent therapeutic intervention through mutational escape. Error-prone genome replication generates heterogeneous viral populations that rapidly adapt to new selection pressures, leading to resistance that emerges with treatment. However, population heterogeneity bears a cost: when multiple viral variants replicate within a cell, they can potentially interfere with each other, lowering viral fitness. This genetic interference can be exploited for antiviral strategies, either by taking advantage of a virus's inherent genetic diversity or through generating de novo interference by engineering a competing genome. Here, we discuss two such antiviral strategies, dominant drug targeting and therapeutic interfering particles. Both strategies harness the power of genetic interference to surmount two particularly vexing obstacles-the evolution of drug resistance and targeting therapy to high-risk populations-both of which impede treatment in resource-poor settings. PMID:27149616

  7. Distribution of arthropods in rice grains in Malaysia

    Institute of Scientific and Technical Information of China (English)

    Mariana A; Ho TM; Lau TY; Heah SK; Wong AL

    2009-01-01

    Objective:To determine distribution of arthropods in rice grains obtained from different sources.Methods:Rice samples were randomly collected from public in urban areas,farmers in rice field areas,aborigines in un-developed areas and retailers in commercial premises.Random samples of rice were taken out from each sam-ple for isolation of arthropods using a modified Berlese Tullgren Funnel Method.Mites were mounted prior to i-dentification;weevils were directly identified.Results:Samples of rice from retailers in commercial premises had the highest infestation by arthropods followed by samples from urbanites,aborigines and rice farmers.Two species of weevils,Sitophilus oryzae(S.oryzae)and Sitophilus granarius(S.granarius),were found.Samples from commercial premises had the least percentage of weevils compared to those collected from domestic premi-ses.Depending on the source of samples,densities of S.granarius and S.oryzae ranges from 1 1 -1 03 weevils? kg and 7-80 weevils?kg,respectively.Important species of mites in stored rice identified were mainly members of the families Cheyletidae,Echimyopodidae,Pyroglyphidae,Saproglyphidae and Tenuipalpidae.Among the species of mites identified were Austroglycyphagus malaysiensis,Cheyletus fortis,Cheyletus malaccensis,Der-matophagoides pteronyssinus,Grammolichus malukuensis and Suidasia pontifica.Average density of most of the mites was less than 40 mites?kg of rice grains.In this study,the highest number of mites in rice samples was recovered from commercial premises,followed by samples from urbanites.Samples from farmers and aborigines contained lesser mites.Conclusion:This study demonstrated the presence of 3 allergenic mite species in rice, i.e A.malaysiensis,D.pteronyssinus and S.pontifica.Weevils,S.oryzae and S.granarius that are known to be allergenic,were also found.

  8. Modulation of antiviral immune responses by exogenous cytokines: effects of tumour necrosis factor-α interleukin-1 α, interleukin-2 and interferon-γ on the immunogenicity of an inactivated rabies vaccine.

    NARCIS (Netherlands)

    V.E.C.J. Schijns; I.J.Th.M. Claassen (Ivo); A.A. Vermeulen; M.C. Horzinek; A.D.M.E. Osterhaus (Albert)

    1994-01-01

    textabstractIn vivo administration of exogenous cytokines may influence elicited immune responses, and hence may change the efficacy of a vaccine. We investigated the effects of tumour necrosis factor-alpha (TNF-alpha), interleukin-1 alpha (IL-1 alpha), interleukin-2 (IL-2) and interferon-gamma (IFN

  9. Negative feedback regulation of cellular antiviral signaling by RBCK1-mediated degradation of IRF3

    Institute of Scientific and Technical Information of China (English)

    Min Zhang; Yang Tian; Rui-Peng Wang; Dong Gao; Yan Zhang; Fei-Ci Diao; Dan-Ying Chen; Zhong-He Zhai; Hong-Bing Shu

    2008-01-01

    Viral infection causes host cells to produce type Ⅰ interferons (IFNs), which are critically involved in viral clearance. Previous studies have demonstrated that activation of the transcription factor interferon regulatory factor (IRF)3 is essential for virus-triggered induction of type Ⅰ IFNs. Here we show that the E3 ubiquitin ligase RBCC protein interact-ing with PKC1 (RBCK1) catalyzes the ubiquitination and degradation of IRF3. Overexpression of RBCK1 negatively regulates Sendai virus-triggered induction of type Ⅰ IFNs, while knockdown of RBCK1 has the opposite effect. Plaque assays consistently demonstrate that RBCK1 negatively regulates the cellular antiviral response. Furthermore, viral infection leads to induction of RBCK1 and subsequent degradation of IRF3. These findings suggest that the cellular antiviral response is controlled by a negative feedback regulatory mechanism involving RBCK1-mediated ubiquitina-tion and degradation of IRF3.

  10. Impacts of major predators on tropical agroforest arthropods: comparisons within and across taxa.

    Science.gov (United States)

    Philpott, Stacy M; Greenberg, Russell; Bichier, Peter; Perfecto, Ivette

    2004-06-01

    In food web studies, taxonomically unrelated predators are often grouped into trophic levels regardless of their relative importance on prey assemblages, multiple predator effects, or interactions such as omnivory. Ants and birds are important predators likely to differentially shape arthropod assemblages, but no studies have compared their effects on a shared prey base. In two separate studies, we excluded birds and ants from branches of a canopy tree ( Inga micheliana) in a coffee farm in Mexico for 2 months in the dry and wet seasons of 2002. We investigated changes in arthropod densities with and without predation pressure from (1) birds and (2) ant assemblages dominated by one of two ant species ( Azteca instabilis and Camponotus senex). We first analyzed individual effects of each predator (birds, Azteca instabilis, and C. senex) then used a per day effect metric to compare differences in effects across (birds vs ants) and within predator taxa (the two ant species). Individually, birds reduced densities of total and large arthropods and some arthropod orders (e.g., spiders, beetles, roaches) in both seasons. Azteca instabilis did not significantly affect arthropods (total, small, large or specific orders). Camponotus senex, however, tended to remove arthropods (total, small), especially in the dry season, and affected arthropod densities of some orders both positively and negatively. Predators greatly differed in their effects on Inga arthropods (for all, small, large, and individual orders of arthropods) both in sign (+/-) and magnitudes of effects. Birds had stronger negative effects on arthropods than ants and the two dominant ant species had stronger effects on arthropods in different seasons. Our results show that aggregating taxonomically related and unrelated predators into trophic levels without prior experimental data quantifying the sign and strengths of effects may lead to a misrepresentation of food web interactions. PMID:15095089

  11. Interactions among predators and the cascading effects of vertebrate insectivores on arthropod communities and plants.

    Science.gov (United States)

    Mooney, Kailen A; Gruner, Daniel S; Barber, Nicholas A; Van Bael, Sunshine A; Philpott, Stacy M; Greenberg, Russell

    2010-04-20

    Theory on trophic interactions predicts that predators increase plant biomass by feeding on herbivores, an indirect interaction called a trophic cascade. Theory also predicts that predators feeding on predators, or intraguild predation, will weaken trophic cascades. Although past syntheses have confirmed cascading effects of terrestrial arthropod predators, we lack a comprehensive analysis for vertebrate insectivores-which by virtue of their body size and feeding habits are often top predators in these systems-and of how intraguild predation mediates trophic cascade strength. We report here on a meta-analysis of 113 experiments documenting the effects of insectivorous birds, bats, or lizards on predaceous arthropods, herbivorous arthropods, and plants. Although vertebrate insectivores fed as intraguild predators, strongly reducing predaceous arthropods (38%), they nevertheless suppressed herbivores (39%), indirectly reduced plant damage (40%), and increased plant biomass (14%). Furthermore, effects of vertebrate insectivores on predatory and herbivorous arthropods were positively correlated. Effects were strongest on arthropods and plants in communities with abundant predaceous arthropods and strong intraguild predation, but weak in communities depauperate in arthropod predators and intraguild predation. The naturally occurring ratio of arthropod predators relative to herbivores varied tremendously among the studied communities, and the skew to predators increased with site primary productivity and in trees relative to shrubs. Although intraguild predation among arthropod predators has been shown to weaken herbivore suppression, we find this paradigm does not extend to vertebrate insectivores in these communities. Instead, vertebrate intraguild preda-tion is associated with strengthened trophic cascades, and insectivores function as dominant predators in terrestrial plant-arthropod communities. PMID:20368418

  12. Genome-wide analysis of antiviral signature genes in porcine macrophages at different activation statuses.

    Directory of Open Access Journals (Sweden)

    Yongming Sang

    Full Text Available Macrophages (MФs can be polarized to various activation statuses, including classical (M1, alternative (M2, and antiviral states. To study the antiviral activation status of porcine MФs during porcine reproductive and respiratory syndrome virus (PRRSV infection, we used RNA Sequencing (RNA-Seq for transcriptomic analysis of differentially expressed genes (DEGs. Sequencing assessment and quality evaluation showed that our RNA-Seq data met the criteria for genome-wide transcriptomic analysis. Comparisons of any two activation statuses revealed more than 20,000 DEGs that were normalized to filter out 153-5,303 significant DEGs [false discovery rate (FDR ≤0.001, fold change ≥2] in each comparison. The highest 5,303 significant DEGs were found between lipopolysaccharide- (LPS and interferon (IFNγ-stimulated M1 cells, whereas only 153 significant DEGs were detected between interleukin (IL-10-polarized M2 cells and control mock-activated cells. To identify signature genes for antiviral regulation pertaining to each activation status, we identified a set of DEGs that showed significant up-regulation in only one activation state. In addition, pathway analyses defined the top 20-50 significantly regulated pathways at each activation status, and we further analyzed DEGs pertinent to pathways mediated by AMP kinase (AMPK and epigenetic mechanisms. For the first time in porcine macrophages, our transcriptomic analyses not only compared family-wide differential expression of most known immune genes at different activation statuses, but also revealed transcription evidence of multiple gene families. These findings show that using RNA-Seq transcriptomic analyses in virus-infected and status-synchronized macrophages effectively profiled signature genes and gene response pathways for antiviral regulation, which may provide a framework for optimizing antiviral immunity and immune homeostasis.

  13. Antiviral Treatment among Pregnant Women with Chronic Hepatitis B

    Directory of Open Access Journals (Sweden)

    Lin Fan

    2014-01-01

    Full Text Available Objective. To describe the antiviral treatment patterns for chronic hepatitis B (CHB among pregnant and nonpregnant women. Methods. Using 2011 MarketScan claims, we calculated the rates of antiviral treatment among women (aged 10–50 years with CHB. We described the pattern of antiviral treatment during pregnancy and ≥1 month after delivery. Results. We identified 6274 women with CHB during 2011. Among these, 64 of 507 (12.6% pregnant women and 1151 of 5767 (20.0% nonpregnant women received antiviral treatment (P < 0.01. Pregnant women were most commonly prescribed tenofovir (73.4% and lamivudine (21.9%; nonpregnant women were most commonly prescribed tenofovir (50.2% and entecavir (41.3% (P < 0.01. Among 48 treated pregnant women with an identifiable delivery date, 16 (33.3% were prescribed an antiviral before pregnancy and continued treatment for at least one month after delivery; 14 (29.2% started treatment during the third trimester and continued at least one month after delivery. Conclusion. Among this insured population, pregnant women with CHB received an antiviral significantly less often than nonpregnant women. The most common antiviral prescribed for pregnant women was tenofovir. These data provide a baseline for assessing changes in treatment patterns with anticipated increased use of antivirals to prevent breakthrough perinatal hepatitis B virus infection.

  14. Antiviral Treatment among Pregnant Women with Chronic Hepatitis B

    Science.gov (United States)

    Fan, Lin; Owusu-Edusei, Kwame; Schillie, Sarah F.; Murphy, Trudy V.

    2014-01-01

    Objective. To describe the antiviral treatment patterns for chronic hepatitis B (CHB) among pregnant and nonpregnant women. Methods. Using 2011 MarketScan claims, we calculated the rates of antiviral treatment among women (aged 10–50 years) with CHB. We described the pattern of antiviral treatment during pregnancy and ≥1 month after delivery. Results. We identified 6274 women with CHB during 2011. Among these, 64 of 507 (12.6%) pregnant women and 1151 of 5767 (20.0%) nonpregnant women received antiviral treatment (P < 0.01). Pregnant women were most commonly prescribed tenofovir (73.4%) and lamivudine (21.9%); nonpregnant women were most commonly prescribed tenofovir (50.2%) and entecavir (41.3%) (P < 0.01). Among 48 treated pregnant women with an identifiable delivery date, 16 (33.3%) were prescribed an antiviral before pregnancy and continued treatment for at least one month after delivery; 14 (29.2%) started treatment during the third trimester and continued at least one month after delivery. Conclusion. Among this insured population, pregnant women with CHB received an antiviral significantly less often than nonpregnant women. The most common antiviral prescribed for pregnant women was tenofovir. These data provide a baseline for assessing changes in treatment patterns with anticipated increased use of antivirals to prevent breakthrough perinatal hepatitis B virus infection. PMID:25548510

  15. An innate antiviral pathway acting before interferons at epithelial surfaces

    DEFF Research Database (Denmark)

    Iversen, Marie B; Reinert, Line S; Thomsen, Martin K;

    2015-01-01

    we identify an innate antiviral pathway that works at epithelial surfaces before the IFNs. The pathway is activated independently of known innate sensors of viral infections through a mechanism dependent on viral O-linked glycans, which induce CXCR3 chemokines and stimulate antiviral activity in a...

  16. Antivirals reduce the formation of key Alzheimer's disease molecules in cell cultures acutely infected with herpes simplex virus type 1.

    Directory of Open Access Journals (Sweden)

    Matthew A Wozniak

    Full Text Available Alzheimer's disease (AD afflicts around 20 million people worldwide and so there is an urgent need for effective treatment. Our research showing that herpes simplex virus type 1 (HSV1 is a risk factor for AD for the brains of people who possess a specific genetic factor and that the virus causes accumulation of key AD proteins (β-amyloid (Aβ and abnormally phosphorylated tau (P-tau, suggests that anti-HSV1 antiviral agents might slow AD progression. However, currently available antiviral agents target HSV1 DNA replication and so might be successful in AD only if Aβ and P-tau accumulation depend on viral DNA replication. Therefore, we investigated firstly the stage(s of the virus replication cycle required for Aβ and P-tau accumulation, and secondly whether antiviral agents prevent these changes using recombinant strains of HSV1 that progress only partly through the replication cycle and antiviral agents that inhibit HSV1 DNA replication. By quantitative immunocytochemistry we demonstrated that entry, fusion and uncoating of HSV1, are insufficient to induce Aβ and P-tau production. We showed also that none of the "immediate early" viral proteins is directly responsible, and that Aβ and P-tau are produced at a subsequent stage of the HSV1 replication cycle. Importantly, the anti-HSV1 antiviral agents acyclovir, penciclovir and foscarnet reduced Aβ and P-tau accumulation, as well as HSV1, with foscarnet being less effective in each case. P-tau accumulation was found to depend on HSV1 DNA replication, whereas Aβ accumulation was not. The antiviral-induced decrease in Aβ is attributable to the reduced number of new viruses, and hence the reduction in viral spread. Since antiviral agents reduce greatly Aβ and P-tau accumulation in HSV1-infected cells, they would be suitable for treating AD with great advantage unlike current AD therapies, only the virus, not the host cell, would be targeted.

  17. Short- and medium-term effects of experimental nitrogen fertilization on arthropods associated with Calluna vulgaris heathlands in north-west Spain

    International Nuclear Information System (INIS)

    We studied the short- and medium-term effects of experimental nitrogen fertilization (3 and 15 months after the treatment) on the arthropods of Calluna vulgaris heathlands in NW Spain. Three heathland sites were selected with two permanent plots per site: control and fertilized. Ammonium nitrate fertilizer (56 kg N ha-1 yr-1) was applied monthly and insects were caught using pitfall traps. We found mainly species-level responses to nitrogen addition. Seven species (e.g. Lochmaea suturalis) showed a consistent trend (benefited or harmed) in both periods and were proposed as possible reliable indicators of the effects of nitrogen deposition in these ecosystems. We also found variable arthropod trophic-group responses: (a) herbivores (leaf beetles, true bugs) increased in abundance on a short-term scale; (b) predators (carabid beetles, true bugs) showed opposite and less clear responses in both periods. Further long-term studies are needed to determine the mechanisms underlying the observed arthropod responses. - We observed consistent species-level and variable trophic-group responses to nitrogen addition in one of the southern-most locations for Calluna vulgaris heathlands within Europe

  18. Antiviral activity of luteolin against Japanese encephalitis virus.

    Science.gov (United States)

    Fan, Wenchun; Qian, Suhong; Qian, Ping; Li, Xiangmin

    2016-07-15

    Japanese encephalitis virus (JEV), a member of family Flaviviridae, is a neurotropic flavivirus that causes Japanese encephalitis (JE). JEV is one of the most important causative agents of viral encephalitis in humans, and this disease leads to high fatality rates. Although effective vaccines are available, no effective antiviral therapy for JE has been developed. Hence, identifying effective antiviral agents against JEV infection is important. In this study, we found that luteolin was an antiviral bioflavonoid with potent antiviral activity against JEV replication in A549 cells with IC50=4.56μg/mL. Luteolin also showed extracellular virucidal activity on JEV. With a time-of-drug addition assay revealing that JEV replication was inhibited by luteolin after the entry stage. Overall, our results suggested that luteolin can be used to develop an antiviral drug against JEV. PMID:27126774

  19. Genetic variation in functional traits influences arthropod community composition in aspen (Populus tremula L.).

    Science.gov (United States)

    Robinson, Kathryn M; Ingvarsson, Pär K; Jansson, Stefan; Albrectsen, Benedicte R

    2012-01-01

    We conducted a study of natural variation in functional leaf traits and herbivory in 116 clones of European aspen, Populus tremula L., the Swedish Aspen (SwAsp) collection, originating from ten degrees of latitude across Sweden and grown in a common garden. In surveys of phytophagous arthropods over two years, we found the aspen canopy supports nearly 100 morphospecies. We identified significant broad-sense heritability of plant functional traits, basic plant defence chemistry, and arthropod community traits. The majority of arthropods were specialists, those coevolved with P. tremula to tolerate and even utilize leaf defence compounds. Arthropod abundance and richness were more closely related to plant growth rates than general chemical defences and relationships were identified between the arthropod community and stem growth, leaf and petiole morphology, anthocyanins, and condensed tannins. Heritable genetic variation in plant traits in young aspen was found to structure arthropod community; however no single trait drives the preferences of arthropod folivores among young aspen genotypes. The influence of natural variation in plant traits on the arthropod community indicates the importance of maintaining genetic variation in wild trees as keystone species for biodiversity. It further suggests that aspen can be a resource for the study of mechanisms of natural resistance to herbivores.

  20. Genetic variation in functional traits influences arthropod community composition in aspen (Populus tremula L..

    Directory of Open Access Journals (Sweden)

    Kathryn M Robinson

    Full Text Available We conducted a study of natural variation in functional leaf traits and herbivory in 116 clones of European aspen, Populus tremula L., the Swedish Aspen (SwAsp collection, originating from ten degrees of latitude across Sweden and grown in a common garden. In surveys of phytophagous arthropods over two years, we found the aspen canopy supports nearly 100 morphospecies. We identified significant broad-sense heritability of plant functional traits, basic plant defence chemistry, and arthropod community traits. The majority of arthropods were specialists, those coevolved with P. tremula to tolerate and even utilize leaf defence compounds. Arthropod abundance and richness were more closely related to plant growth rates than general chemical defences and relationships were identified between the arthropod community and stem growth, leaf and petiole morphology, anthocyanins, and condensed tannins. Heritable genetic variation in plant traits in young aspen was found to structure arthropod community; however no single trait drives the preferences of arthropod folivores among young aspen genotypes. The influence of natural variation in plant traits on the arthropod community indicates the importance of maintaining genetic variation in wild trees as keystone species for biodiversity. It further suggests that aspen can be a resource for the study of mechanisms of natural resistance to herbivores.

  1. Modification and application of a leaf blower-vac for field sampling of arthropods

    NARCIS (Netherlands)

    Zou, Yi; Telgen, van Mario D.; Chen, Junhui; Xiao, Haijun; Kraker, de Joop; Bianchi, Felix J.J.A.; Werf, van der Wopke

    2016-01-01

    Rice fields host a large diversity of arthropods, but investigating their population dynamics and interactions is challenging. Here we describe the modification and application of a leaf blower-vac for suction sampling of arthropod populations in rice. When used in combination with an enclosure,

  2. Effects of weed harrowing frequency on beneficial arthropods, plants and crop yield

    DEFF Research Database (Denmark)

    Navntoft, Søren; Kristensen, Kristian; Johnsen, Ib;

    2016-01-01

    * Weed harrowing is an alternative to herbicides but it may have negative effects on epigaeic arthropods. We assessed the effects of frequent (four) versus two harrowings during the growing season on the density and diversity of generalist arthropods and the weed flora. Collection by flooding was...

  3. "Bugs on Bugs": An Inquiry-Based, Collaborative Activity to Learn Arthropod & Microbial Biodiversity

    Science.gov (United States)

    Lampert, Evan C.; Morgan, Jeanelle M.

    2015-01-01

    Diverse communities of arthropods and microbes provide humans with essential ecosystem goods and services. Arthropods are the most diverse and abundant macroscopic animals on the planet, and many remain to be discovered. Much less is known about microbial diversity, despite their importance as free-living species and as symbionts. We created…

  4. Arthropods in no-tillage soybean agroecosystems: Community composition and ecosystem interactions

    Science.gov (United States)

    House, Garfield J.; Stinner, Benjamin R.

    1983-01-01

    Sampling data are provided and concepts discussed regarding soil and foliage arthropod communities in conventional and no-tillage soybean agroecosystems Soil arthropod communities from the two cropping systems were also compared with that from an adjacent old field. Biweekly arthropod samples were collected from conventional, no-tillage, and old-field systems Soil arthropods were sampled by quadrat and pitfall trap methods, foliage arthropods were collected by sweep net Quadrat sampling revealed that ground beetle number, species diversity, and biomass were significantly higher ( Ptrap data indicated higher densities and species diversity for most major soil macro-arthropod guilds Foliage arthropod guilds from no-tillage treatments showed higher species diversity throughout the growing season than those of conventional tillage, possibly because of greater structural diversity provided by weeds and litter in notillage systems No-tillage systems supported a larger and more diverse arthropod community than conventionally grown soybeans, suggesting a need for pest management strategies that simultaneously consider many variables. Both foliar grazing and leaf nitrogen content were higher in conventional than in no-tillage systems, indicating a possible causal connection between soil tillage and insect herbivory rates

  5. Composition and Diversity of Soil Arthropods of Rajegwesi Meru Betiri National Park

    Directory of Open Access Journals (Sweden)

    Hasan Zayadi

    2013-09-01

    Full Text Available Meru Betiri National Park (MBNP is one of the nature conservation area that has the potential of flora, fauna, and ecosystems that could develop as a nature-based tourism attraction. The existence of certain indicator species was related to estimation of stress level and disturbance on ecosystem stability for making strategic decisions about the restoration in this area. One of the important indicator species at forest ecosystem were soil arthropods. Aim this research were analyzed composition and diversity of soil arthropods at Rajegwesi, MBNP areas. The methods in this research used pitfall trap, measurement of distribution structure and soil arthropods composition based on the Shannon - Wiener index, Morisita similarity index and Importance Value Index (IVI. The number of families and individuals of soil arthropods found in the coastal area of Rajegwesi consists of 10 order with 21 families (702 individual. The number of individuals of the order Hymenoptera, Coleoptera, Collembola and Araneida was more widely found. Soil arthropods diversity index on each land use indicated that soil arthropod diversity in these areas were moderate. Soil arthropod community of orchards and forest had a similarity of species composition, whereas soil arthropod community of savanna had a similarity of species composition with paddy fields.

  6. Reduced-risk pest management programs for eastern U.S. peach orchards: effects on arthropod predators, parasitoids, and select pests.

    Science.gov (United States)

    Biddinger, David J; Leslie, Timothy W; Joshi, Neelendra K

    2014-06-01

    We developed new integrated pest management programs for eastern U.S. peaches with minimal use of organophosphates. From 2002-2005, we assessed the ecological impacts of these reduced-risk programs versus grower standard conventional programs that still relied primarily on the use of organophosphorous and carbamate insecticides. Using a split-plot design replicated at four commercial Pennsylvania peach orchards, we quantified pesticide rates, environmental impact, and arthropod community response. We used Environmental Impact Quotient (EIQ) analysis based on the growers' pesticide records from each orchard to calculate seasonal cumulative EIQ field ratings for all years. Ecological effects of the reduced-risk and conventional program were also measured as the abundance and diversity of nontarget arthropod predators, parasitoids, and selected pest taxa. Pesticide inputs and EIQ values were substantially lower in reduced-risk programs compared with conventional spray programs. Arthropod arrays differed significantly between pest management programs: most beneficial predator and parasitoid taxa were positively associated with the reduced-risk program and negatively associated with the standard grower program. Regardless of the pest management program, we observed significant differences in species arrays in the peach tree canopy compared with the ground cover of the orchards, but the arthropod community did not differ among the field sites or based on distance from the edge of the orchard. We conclude that reduced-risk programs not only provide control comparable with that of conventional programs, but they also reduce negative environmental effects while conserving key arthropod biological control agents within eastern U.S. peach orchards.

  7. The importance of arthropod pests in Belgian pome fruit orchards.

    Science.gov (United States)

    Bangels, Eva; De Schaetzen, Charles; Hayen, Guy; Paternotte, Edouard; Gobin, Bruno

    2008-01-01

    Located in temperate, maritime climate with frequent rainfall, crop protection in Belgian orchards is dominated by fungicides. Though, the importance of arthropod pests should not be underestimated. Pcfruit, the former Research station of Gorsem, has been maintaining a warning system for fruit pests in Belgium since 1944. Therefore, various pests and beneficial's and their life cycle stages have been monitored in Gorsem and in different observation posts across Belgium, being part of a monitoring network. Although up to 3000 arthropod species are present in pome fruit orchards, about 25% can be considered as harmful and another 25% as beneficial. Out of those species, around 100 harmful and 50 beneficial organisms are omnipresent. The list of monitored species is extended yearly for upcoming or difficult to control organisms. Integrated pest management was introduced in the eighties, with the accent on using selective pesticides and saving beneficial organisms. A shift in pesticide use affected the importance of secondary pests, together with recent exceptional climatic conditions. Following many years of monitoring insects and mites and editing warning bulletins in our station, a ranking of the economical importance of different pest species is presented.

  8. Character combinations, convergence and diversification in ectoparasitic arthropods.

    Science.gov (United States)

    Poulin, Robert

    2009-08-01

    Different lineages of organisms diversify over time at different rates, in part as a consequence of the characteristics of the species in these lineages. Certain suites of traits possessed by species within a clade may determine rates of diversification, with some particular combinations of characters acting synergistically to either limit or promote diversification; the most successful combinations may also emerge repeatedly in different clades via convergent evolution. Here, the association between species characters and diversification is investigated amongst 21 independent lineages of arthropods ectoparasitic on vertebrate hosts. Using nine characters (each with two to four states) that capture general life history strategy, transmission mode and host-parasite interaction, each lineage was described by the set of character states it possesses. The results show, firstly, that most possible pair-wise combinations of character states have been adopted at least once, sometimes several times independently by different lineages; thus, ectoparasitic arthropods have explored most of the life history character space available to them. Secondly, lineages possessing commonly observed combinations of character states are not necessarily the ones that have experienced the highest rates of diversification (measured as a clade's species-per-genus ratio). Thirdly, some specific traits are associated with higher rates of diversification. Using more than one host per generation, laying eggs away from the host and intermediate levels of fecundity are features that appear to have promoted diversification. These findings indicate that particular species characters may be evolutionary drivers of diversity, whose effects could also apply in other taxa.

  9. Arthropod succession on pig carcasses in southeastern Nigeria

    Directory of Open Access Journals (Sweden)

    M.S. Ekanem

    2010-01-01

    Full Text Available The domestic pig (Sus scrofa was used as a model to study arthropod succession on carcasses under tree shade and out of shade in southern Nigeria. Carcass decomposition took longer periods under tree shade than in exposed sites, at 24.5 and 16.5 days, respectively. Four decomposition stages - fresh, bloated, decay, and dry - were observed. No significant variabilities were recorded in the types and patterns of infestation of the carcasses by arthropods in both locations. Four classes of arthropods - Insecta, Arachnida, Diplopoda and Crustacea - were recorded. The class Insecta dominated the total arthropods collected with 24 families, and formed 94% of the catches. The other three classes each had one family represented, and contributed only 2% of the total catches. The calliphorids, a phorid, and sarcophagids arrived and bred on the carcasses only a few hours after death of the pigs. Families of coleopterans came during the bloated stage, and fed on the immature dipterous maggots and carrion materials. The ants (Hymenoptera came in large numbers to eat the carcasses, and also preyed on all other fauna of the food resource. A muscid and a stratiomyiid, bred on the carcass as to the decay stage. Other insects and arthropods arrived mostly during the decay stage to feed on the carcasses. Species richness on the carcasses peaked during the decay stage.O porco branco (Sus scrofa foi usado como modelo para o estudo da sucessão de Artrópodes em cadáveres em zonas sombreadas e não sombreadas por árvores no sul da Nigéria. Nos cadáveres em decomposição em zonas sombreadas observou-se um processo de decomposição mais lento que nos expostos ao sol; 24,5 e 16,5 dias, respectivamente. Foram observadas quatro etapas de decomposição; fresco (autólise, intumescido (putrefação, deteriorado e seco (diagênese. Não foram observadas diferenças significativas de tipo e padrão nas infestações dos cadáveres por Artrópodes em ambas as condi

  10. Baseline MELD score predicts hepatic decompensation during antiviral therapy in patients with chronic hepatitis C and advanced cirrhosis.

    Directory of Open Access Journals (Sweden)

    Georg Dultz

    Full Text Available BACKGROUND AND AIMS: In patients with advanced liver cirrhosis due to chronic hepatitis C virus (HCV infection antiviral therapy with peginterferon and ribavirin is feasible in selected cases only due to potentially life-threatening side effects. However, predictive factors associated with hepatic decompensation during antiviral therapy are poorly defined. METHODS: In a retrospective cohort study, 68 patients with HCV-associated liver cirrhosis (mean MELD score 9.18 ± 2.72 were treated with peginterferon and ribavirin. Clinical events indicating hepatic decompensation (onset of ascites, hepatic encephalopathy, upper gastrointestinal bleeding, hospitalization as well as laboratory data were recorded at baseline and during a follow up period of 72 weeks after initiation of antiviral therapy. To monitor long term sequelae of end stage liver disease an extended follow up for HCC development, transplantation and death was applied (240 weeks, ± SD 136 weeks. RESULTS: Eighteen patients (26.5% achieved a sustained virologic response. During the observational period a hepatic decompensation was observed in 36.8%. Patients with hepatic decompensation had higher MELD scores (10.84 vs. 8.23, p14, respectively. Baseline MELD score was significantly associated with the risk for transplantation/death (p<0.001. CONCLUSIONS: Our data suggest that the baseline MELD score predicts the risk of hepatic decompensation during antiviral therapy and thus contributes to decision making when antiviral therapy is discussed in HCV patients with advanced liver cirrhosis.

  11. Silicon: Potential to Promote Direct and Indirect Effects on Plant Defense Against Arthropod Pests in Agriculture.

    Science.gov (United States)

    Reynolds, Olivia L; Padula, Matthew P; Zeng, Rensen; Gurr, Geoff M

    2016-01-01

    Silicon has generally not been considered essential for plant growth, although it is well recognized that many plants, particularly Poaceae, have substantial plant tissue concentrations of this element. Recently, however, the International Plant Nutrition Institute [IPNI] (2015), Georgia, USA has listed it as a "beneficial substance". This reflects that numerous studies have now established that silicon may alleviate both biotic and abiotic stress. This paper explores the existing knowledge and recent advances in elucidating the role of silicon in plant defense against biotic stress, particularly against arthropod pests in agriculture and attraction of beneficial insects. Silicon confers resistance to herbivores via two described mechanisms: physical and biochemical/molecular. Until recently, studies have mainly centered on two trophic levels; the herbivore and plant. However, several studies now describe tri-trophic effects involving silicon that operate by attracting predators or parasitoids to plants under herbivore attack. Indeed, it has been demonstrated that silicon-treated, arthropod-attacked plants display increased attractiveness to natural enemies, an effect that was reflected in elevated biological control in the field. The reported relationships between soluble silicon and the jasmonic acid (JA) defense pathway, and JA and herbivore-induced plant volatiles (HIPVs) suggest that soluble silicon may enhance the production of HIPVs. Further, it is feasible that silicon uptake may affect protein expression (or modify proteins structurally) so that they can produce additional, or modify, the HIPV profile of plants. Ultimately, understanding silicon under plant ecological, physiological, biochemical, and molecular contexts will assist in fully elucidating the mechanisms behind silicon and plant response to biotic stress at both the bi- and tri-trophic levels. PMID:27379104

  12. Immunomodulating and antiviral therapy in herpes zoster.

    Science.gov (United States)

    Topciu, V; Mihăilescu, R

    1996-01-01

    Two groups of patients with herpes zoster were followed up. The first group was subjected, beside a symptomatic therapy, to an immunological and antiviral treatment. The control group was treated only symptomatically. The immunological preparations used were: the immunostimulant SRE (Corynebacterium parvum), which stimulated the lymphocytes and macrophages, Moroxidin (Virustat-Paris) and Antiherpin (interferon inductor), which acted by blocking the virus replication. The preparations were indigenous and atoxic. A significant difference between the courses of disease in the two groups was observed, namely, the severity and duration of subjective and objective symptoms were more than double and followed by persistent neurological sequelae in the control group in comparison with the patients of the experimental group. PMID:9495784

  13. Novel concept on antiviral strategies to dengue.

    Science.gov (United States)

    Lo, Yu-Chih; Perng, Guey Chuen

    2016-06-01

    Recent evidence has revealed that asymptomatic and/or persistent dengue virus (DENV) infections play a role in the cycling pattern of dengue outbreaks. These findings add a new dimension to the continually evolving search for effective prevention strategies in dengue. Disappointing outcomes of clinical trials in anti-dengue modalities have become commonplace. These failures may result from confounding variables and/or unresolved scientific issues that surround dengue, including the replication cycle of DENV in a natural setting, the target cells and reservoir for viral replication in vivo, and the effect of asymptomatic/persistent carriers in the dissemination of dengue. This article sets forth to address these issues using the most updated information available in the literature and to propose a novel antiviral strategy for the prevention and control of dengue. PMID:27284691

  14. RNAi:antiviral therapy against dengue virus

    Institute of Scientific and Technical Information of China (English)

    Sobia Idrees; Usman A Ashfaq

    2013-01-01

    Dengue virus infection has become a global threat affecting around 100 countries in the world. Currently, there is no licensed antiviral agent available against dengue. Thus, there is a strong need to develop therapeutic strategies that can tackle this life threatening disease. RNA interference is an important and effective gene silencing process which degrades targeted RNA by a sequence specific process. Several studies have been conducted during the last decade to evaluate the efficiency of siRNA in inhibiting dengue virus replication. This review summarizes siRNAs as a therapeutic approach against dengue virus serotypes and concludes that siRNAs against virus and host genes can be next generation treatment of dengue virus infection.

  15. Antifungal and antiviral products of marine organisms.

    Science.gov (United States)

    Cheung, Randy Chi Fai; Wong, Jack Ho; Pan, Wen Liang; Chan, Yau Sang; Yin, Cui Ming; Dan, Xiu Li; Wang, He Xiang; Fang, Evandro Fei; Lam, Sze Kwan; Ngai, Patrick Hung Kui; Xia, Li Xin; Liu, Fang; Ye, Xiu Yun; Zhang, Guo Qing; Liu, Qing Hong; Sha, Ou; Lin, Peng; Ki, Chan; Bekhit, Adnan A; Bekhit, Alaa El-Din; Wan, David Chi Cheong; Ye, Xiu Juan; Xia, Jiang; Ng, Tzi Bun

    2014-04-01

    Marine organisms including bacteria, fungi, algae, sponges, echinoderms, mollusks, and cephalochordates produce a variety of products with antifungal activity including bacterial chitinases, lipopeptides, and lactones; fungal (-)-sclerotiorin and peptaibols, purpurides B and C, berkedrimane B and purpuride; algal gambieric acids A and B, phlorotannins; 3,5-dibromo-2-(3,5-dibromo-2-methoxyphenoxy)phenol, spongistatin 1, eurysterols A and B, nortetillapyrone, bromotyrosine alkaloids, bis-indole alkaloid, ageloxime B and (-)-ageloxime D, haliscosamine, hamigeran G, hippolachnin A from sponges; echinoderm triterpene glycosides and alkene sulfates; molluscan kahalalide F and a 1485-Da peptide with a sequence SRSELIVHQR; and cepalochordate chitotriosidase and a 5026.9-Da antifungal peptide. The antiviral compounds from marine organisms include bacterial polysaccharide and furan-2-yl acetate; fungal macrolide, purpurester A, purpurquinone B, isoindolone derivatives, alterporriol Q, tetrahydroaltersolanol C and asperterrestide A, algal diterpenes, xylogalactofucan, alginic acid, glycolipid sulfoquinovosyldiacylglycerol, sulfated polysaccharide p-KG03, meroditerpenoids, methyl ester derivative of vatomaric acid, lectins, polysaccharides, tannins, cnidarian zoanthoxanthin alkaloids, norditerpenoid and capilloquinol; crustacean antilipopolysaccharide factors, molluscan hemocyanin; echinoderm triterpenoid glycosides; tunicate didemnin B, tamandarins A and B and; tilapia hepcidin 1-5 (TH 1-5), seabream SauMx1, SauMx2, and SauMx3, and orange-spotted grouper β-defensin. Although the mechanisms of antifungal and antiviral activities of only some of the aforementioned compounds have been elucidated, the possibility to use those known to have distinctly different mechanisms, good bioavailability, and minimal toxicity in combination therapy remains to be investigated. It is also worthwhile to test the marine antimicrobials for possible synergism with existing drugs. The prospects of

  16. Assessment of Antiviral Properties of Peramivir against H7N9 Avian Influenza Virus in an Experimental Mouse Model.

    Science.gov (United States)

    Farooqui, Amber; Huang, Linxi; Wu, Suwu; Cai, Yingmu; Su, Min; Lin, Pengzhou; Chen, Weihong; Fang, Xibin; Zhang, Li; Liu, Yisu; Zeng, Tiansheng; Paquette, Stephane G; Khan, Adnan; Kelvin, Alyson A; Kelvin, David J

    2015-12-01

    The H7N9 influenza virus causes a severe form of disease in humans. Neuraminidase inhibitors, including oral oseltamivir and injectable peramivir, are the first choices of antiviral treatment for such cases; however, the clinical efficacy of these drugs is questionable. Animal experimental models are essential for understanding the viral replication kinetics under the selective pressure of antiviral agents. This study demonstrates the antiviral activity of peramivir in a mouse model of H7N9 avian influenza virus infection. The data show that repeated administration of peramivir at 30 mg/kg of body weight successfully eradicated the virus from the respiratory tract and extrapulmonary tissues during the acute response, prevented clinical signs of the disease, including neuropathy, and eventually protected mice against lethal H7N9 influenza virus infection. Early treatment with peramivir was found to be associated with better disease outcomes. PMID:26369969

  17. Zinc-finger antiviral protein inhibits XMRV infection.

    Directory of Open Access Journals (Sweden)

    Xinlu Wang

    Full Text Available BACKGROUND: The zinc-finger antiviral protein (ZAP is a host factor that specifically inhibits the replication of certain viruses, including Moloney murine leukemia virus (MoMLV, HIV-1, and certain alphaviruses and filoviruses. ZAP binds to specific viral mRNAs and recruits cellular mRNA degradation machinery to degrade the target RNA. The common features of ZAP-responsive RNA sequences remain elusive and thus whether a virus is susceptible to ZAP can only be determined experimentally. Xenotropic murine leukemia virus-related virus (XMRV is a recently identified γ-retrovirus that was originally thought to be involved in prostate cancer and chronic fatigue syndrome but recently proved to be a laboratory artefact. Nonetheless, XMRV as a new retrovirus has been extensively studied. Since XMRV and MoMLV share only 67.9% sequence identity in the 3'UTRs, which is the target sequence of ZAP in MoMLV, whether XMRV is susceptible to ZAP remains to be determined. FINDINGS: We constructed an XMRV-luc vector, in which the coding sequences of Gag-Pol and part of Env were replaced with luciferase-coding sequence. Overexpression of ZAP potently inhibited the expression of XMRV-luc in a ZAP expression-level-dependent manner, while downregulation of endogenous ZAP rendered cells more sensitive to infection. Furthermore, ZAP inhibited the spreading of replication-competent XMRV. Consistent with the previously reported mechanisms by which ZAP inhibits viral infection, ZAP significantly inhibited the accumulation of XMRV-luc mRNA in the cytoplasm. The ZAP-responsive element in XMRV mRNA was mapped to the 3'UTR. CONCLUSIONS: ZAP inhibits XMRV replication by preventing the accumulation of viral mRNA in the cytoplasm. Documentation of ZAP inhibiting XMRV helps to broaden the spectrum of ZAP's antiviral activity. Comparison of the target sequences of ZAP in XMRV and MoMLV helps to better understand the features of ZAP-responsive elements.

  18. Non-MHC genes influence virus clearance through regulation of the antiviral T-cell response: correlation between virus clearance and Tc and Td activity in segregating backcross progeny

    DEFF Research Database (Denmark)

    Christensen, Jan Pravsgaard; Marker, O; Thomsen, Allan Randrup

    1994-01-01

    ) was followed by measurement of footpad swelling. Ten days after virus inoculation, the animals were sacrificed and spleen virus titer together with splenic Tc activity was measured. With regard to all three parameters a continuous distribution was observed in this backcross population. However, using cutoff......To determine the mechanism by which non-MHC genes control the rate of virus clearance in mice infected with lymphocytic choriomeningitis virus, a segregating backcross population was studied. Thirty BC1 animals were infected with virus, and virus-specific delayed-type hypersensitivity (DTH...... values based on parental and F1 animals tested in parallel, 11/30 animals were assigned Tc responders, 23/30 DTH responders and 10/30 cleared virus with maximal efficiency. Comparison of responder status with regard to the different parameters revealed a strong correlation between Tc responsiveness...

  19. Future rainfall variations reduce abundances of aboveground arthropods in model agroecosystems with different soil types

    Directory of Open Access Journals (Sweden)

    Johann G. Zaller

    2014-10-01

    Full Text Available Climate change scenarios for Central Europe predict less frequent but heavier rainfalls and longer drought periods during the growing season. This is expected to alter arthropods in agroecosystems that are important as biocontrol agents, herbivores or food for predators (e.g. farmland birds. In a lysimeter facility (totally 18 3-m2-plots, we experimentally tested the effects of long-term past vs. prognosticated future rainfall variations (15% increased rainfall per event, 25% more dry days according to regionalized climate change models from the Intergovernmental Panel on Climate Change (IPCC on aboveground arthropods in winter wheat (Triticum aestivum L. cultivated at three different soil types (calcaric phaeozem, calcic chernozem and gleyic phaeozem. Soil types were established 17 years and rainfall treatments one month before arthropod sampling; treatments were fully crossed and replicated three times. Aboveground arthropods were assessed by suction sampling, their mean abundances (± SD differed between April, May and June with 20 ± 3 m-2, 90 ± 35 m-2 and 289 ± 93 individuals m-2, respectively. Averaged across sampling dates, future rainfall reduced the abundance of spiders (Araneae, -47%, cicadas and leafhoppers (Auchenorrhyncha, -39%, beetles (Coleoptera, -52%, ground beetles (Carabidae, -41%, leaf beetles (Chrysomelidae, -64%, spring tails (Collembola, -58%, flies (Diptera, -73% and lacewings (Neuroptera, -73% but increased the abundance of snails (Gastropoda, +69%. Across sampling dates, soil types had no effects on arthropod abundances. Arthropod diversity was neither affected by rainfall nor soil types. Arthropod abundance was positively correlated with weed biomass for almost all taxa; abundance of Hemiptera and of total arthropods was positively correlated with weed density. These detrimental effects of future rainfall varieties on arthropod taxa in wheat fields can potentially alter arthropod-associated agroecosystem services.

  20. Antiviral therapy with nucleotide/nucleoside analogues in chronic hepatitis B: A meta-analysis of prospective randomized trials.

    Science.gov (United States)

    Bedre, Renesh H; Raj, Utkarsh; Misra, Sri Prakash; Varadwaj, Pritish Kumar

    2016-03-01

    Nucleotide/nucleoside analogues (antiviral therapy) are used in the therapy of HBeAg positive and HBeAg negative chronic hepatitis B. We analyzed ten selected randomized controlled with 2557 patients to estimate the effect of antiviral drugs in chronic hepatitis B with compared to placebo. Virological response, biochemical response, histological response, seroconversion of HBeAg, and loss of HBeAg were estimated as primary efficacy measures. The included studies were subjected for heterogeneity and publication bias. The heterogeneity was assessed with χ2 and I(2) statistics. Publication bias was assessed by funnel plot. Greater rates of improvement obtained in antiviral group for virological response [43.96 % vs. 3.15 %, RR = 0.57, 95 % CI = 0.54-0.61, p-value pharyngitis [22.22 % vs. 18.23 %, OR = 1.12, 95 % CI = 0.86-1.45, p-value = 0.40]. Excluding adverse events, all primary efficacy measures shown statistical significant result for chronic hepatitis treatment (p-value <0.05). Antiviral therapy provided significant benefit for the treatment of chronic hepatitis B with no measurable adverse effects. PMID:27083430

  1. Herbivore-induced plant volatiles as a rich source of information for arthropod predators: fundamental and applied aspects

    NARCIS (Netherlands)

    Dicke, M.

    2015-01-01

    Plants respond to arthropod herbivory with the induction of volatiles that attract predatory arthropods that attack the herbivores. These so-called herbivore-induced plant volatiles (HIPVs) appear to be important sources of information that mediate many interactions within a plant–arthropod communit

  2. Respiratory syncytial virus (RSV infection in elderly mice results in altered antiviral gene expression and enhanced pathology.

    Directory of Open Access Journals (Sweden)

    Terianne M Wong

    Full Text Available Elderly persons are more susceptible to RSV-induced pneumonia than young people, but the molecular mechanism underlying this susceptibility is not well understood. In this study, we used an aged mouse model of RSV-induced pneumonia to examine how aging alters the lung pathology, modulates antiviral gene expressions, and the production of inflammatory cytokines in response to RSV infection. Young (2-3 months and aged (19-21 months mice were intranasally infected with mucogenic or non-mucogenic RSV strains, lung histology was examined, and gene expression was analyzed. Upon infection with mucogenic strains of RSV, leukocyte infiltration in the airways was elevated and prolonged in aged mice compared to young mice. Minitab factorial analysis identified several antiviral genes that are influenced by age, infection, and a combination of both factors. The expression of five antiviral genes, including pro-inflammatory cytokines IL-1β and osteopontin (OPN, was altered by both age and infection, while age was associated with the expression of 15 antiviral genes. Both kinetics and magnitude of antiviral gene expression were diminished as a result of older age. In addition to delays in cytokine signaling and pattern recognition receptor induction, we found TLR7/8 signaling to be impaired in alveolar macrophages in aged mice. In vivo, induction of IL-1β and OPN were delayed but prolonged in aged mice upon RSV infection compared to young. In conclusion, this study demonstrates inherent differences in response to RSV infection in young vs. aged mice, accompanied by delayed antiviral gene induction and cytokine signaling.

  3. Echinacea—A Source of Potent Antivirals for Respiratory Virus Infections

    Directory of Open Access Journals (Sweden)

    Selvarani Vimalanathan

    2011-07-01

    Full Text Available Extracts of Echinacea species have been used traditionally in North America for the control of symptoms of colds, influenza, and other diseases, and some of them have become very popular as “herbal medicines”. Recent studies have revealed that preparations derived from certain species and plant parts, but not all of them, possess potent antiviral activities, at non-cytotoxic concentrations, particularly against membrane-containing viruses. Thus all strains of human and avian influenza viruses tested (including a Tamiflu-resistant strain, as well as herpes simplex virus, respiratory syncytial virus, and rhinoviruses, were very sensitive to a standardized Echinacea purpurea preparation. In mechanistic studies the influenza virus-specific hemagglutinin and neuraminidase were inhibited. In addition some extracts displayed anti-inflammatory activity in virus-infected cells, and numerous other effects on the expression of cellular genes. Multiple components, either discrete compounds or mixtures, appeared to be responsible for the various antiviral activities.

  4. Leader-Containing Uncapped Viral Transcript Activates RIG-I in Antiviral Stress Granules.

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    Seong-Wook Oh

    2016-02-01

    Full Text Available RIG-I triggers antiviral responses by recognizing viral RNA (vRNA in the cytoplasm. However, the spatio-temporal dynamics of vRNA sensing and signal transduction remain elusive. We investigated the time course of events in cells infected with Newcastle disease virus (NDV, a non-segmented negative-strand RNA virus. RIG-I was recruited to viral replication complexes (vRC and triggered minimal primary type I interferon (IFN production. RIG-I subsequently localized to antiviral stress granules (avSG induced after vRC formation. The inhibition of avSG attenuated secondary IFN production, suggesting avSG as a platform for efficient vRNA detection. avSG selectively captured positive-strand vRNA, and poly(A+ RNA induced IFN production. Further investigations suggested that uncapped vRNA derived from read-through transcription was sensed by RIG-I in avSG. These results highlight how viral infections stimulate host stress responses, thereby selectively recruiting uncapped vRNA to avSG, in which RIG-I and other components cooperate in an efficient antiviral program.

  5. Mechanism of TRIM25 Catalytic Activation in the Antiviral RIG-I Pathway.

    Science.gov (United States)

    Sanchez, Jacint G; Chiang, Jessica J; Sparrer, Konstantin M J; Alam, Steven L; Chi, Michael; Roganowicz, Marcin D; Sankaran, Banumathi; Gack, Michaela U; Pornillos, Owen

    2016-08-01

    Antiviral response pathways induce interferon by higher-order assembly of signaling complexes called signalosomes. Assembly of the RIG-I signalosome is regulated by K63-linked polyubiquitin chains, which are synthesized by the E3 ubiquitin ligase, TRIM25. We have previously shown that the TRIM25 coiled-coil domain is a stable, antiparallel dimer that positions two catalytic RING domains on opposite ends of an elongated rod. We now show that the RING domain is a separate self-association motif that engages ubiquitin-conjugated E2 enzymes as a dimer. RING dimerization is required for catalysis, TRIM25-mediated RIG-I ubiquitination, interferon induction, and antiviral activity. We also provide evidence that RING dimerization and E3 ligase activity are promoted by binding of the TRIM25 SPRY domain to the RIG-I effector domain. These results indicate that TRIM25 actively participates in higher-order assembly of the RIG-I signalosome and helps to fine-tune the efficiency of the RIG-I-mediated antiviral response. PMID:27425606

  6. Increase of cells expressing PD-L1 in bovine leukemia virus infection and enhancement of anti-viral immune responses in vitro via PD-L1 blockade

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    Ikebuchi Ryoyo

    2011-09-01

    Full Text Available Abstract The inhibitory receptor programmed death-1 (PD-1 and its ligand, programmed death-ligand 1 (PD-L1 are involved in immune evasion mechanisms for several pathogens causing chronic infections. Blockade of the PD-1/PD-L1 pathway restores anti-virus immune responses, with concomitant reduction in viral load. In a previous report, we showed that, in bovine leukemia virus (BLV infection, the expression of bovine PD-1 is closely associated with disease progression. However, the functions of bovine PD-L1 are still unknown. To investigate the role of PD-L1 in BLV infection, we identified the bovine PD-L1 gene, and examined PD-L1 expression in BLV-infected cattle in comparison with uninfected cattle. The deduced amino acid sequence of bovine PD-L1 shows high homology to the human and mouse PD-L1. The proportion of PD-L1 positive cells, especially among B cells, was upregulated in cattle with the late stage of the disease compared to cattle at the aleukemic infection stage or uninfected cattle. The proportion of PD-L1 positive cells correlated positively with prediction markers for the progression of the disease such as leukocyte number, virus load and virus titer whilst on the contrary, it inversely correlated with the degree of interferon-gamma expression. Blockade of the PD-1/PD-L1 pathway in vitro by PD-L1-specific antibody upregulated the production of interleukin-2 and interferon-gamma, and correspondingly, downregulated the BLV provirus load and the proportion of BLV-gp51 expressing cells. These data suggest that PD-L1 induces immunoinhibition in disease progressed cattle during chronic BLV infection. Therefore, PD-L1 would be a potential target for developing immunotherapies against BLV infection.

  7. Antiviral Treatment among Pregnant Women with Chronic Hepatitis B

    OpenAIRE

    Lin Fan; Kwame Owusu-Edusei; Schillie, Sarah F.; Murphy, Trudy V.

    2014-01-01

    Objective. To describe the antiviral treatment patterns for chronic hepatitis B (CHB) among pregnant and nonpregnant women. Methods. Using 2011 MarketScan claims, we calculated the rates of antiviral treatment among women (aged 10–50 years) with CHB. We described the pattern of antiviral treatment during pregnancy and ≥1 month after delivery. Results. We identified 6274 women with CHB during 2011. Among these, 64 of 507 (12.6%) pregnant women and 1151 of 5767 (20.0%) nonpregnant women receiv...

  8. Identification of DreI as an antiviral factor regulated by RLR signaling pathway.

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    Shun Li

    Full Text Available BACKGROUND: Retinoic acid-inducible gene I (RIG-I-like receptors (RLRs had been demonstrated to prime interferon (IFN response against viral infection via the conserved RLR signaling in fish, and a novel fish-specific gene, the grass carp reovirus (GCRV-induced gene 2 (Gig2, had been suggested to play important role in host antiviral response. METHODOLOGY/PRINCIPAL FINDINGS: In this study, we cloned and characterized zebrafish Gig2 homolog (named Danio rerio Gig2-I, DreI, and revealed its antiviral role and expressional regulation signaling pathway. RT-PCR, Western blot and promoter activity assay indicate that DreI can be induced by poly I:C, spring viremia of carp virus (SVCV and recombinant IFN (rIFN, showing that DreI is a typical ISG. Using the pivotal signaling molecules of RLR pathway, including RIG-I, MDA5 and IRF3 from crucian carp, it is found that DreI expression is regulated by RLR cascade and IRF3 plays an important role in this regulation. Furthermore, promoter mutation assay confirms that the IFN-stimulated regulatory elements (ISRE in the 5' flanking region of DreI is essential for its induction. Finally, overexpression of DreI leads to establish a strong antiviral state against SVCV and Rana grylio virus (RGV infection in EPC (Epithelioma papulosum cyprinid cells. CONCLUSIONS/SIGNIFICANCE: These data indicate that DreI is an antiviral protein, which is regulated by RLR signaling pathway.

  9. Bio-mathematical models of viral dynamics to tailor antiviral therapy in chronic viral hepatitis

    Institute of Scientific and Technical Information of China (English)

    Maurizia Rossana Brunetto; Piero Colombatto; Ferruccio Bonino

    2009-01-01

    The simulation of the dynamics of viral infections by mathematical equations has been applied successfully to the study of viral infections during antiviral therapy. Standard models applied to viral hepatitis describe the viral load decline in the first 2-4 wk of antiviral therapy, but do not adequately simulate the dynamics of viral infection for the following period. The hypothesis of a constant clearance rate of the infected cells provides an unrealistic estimation of the time necessary to reach the control or the clearance of hepatitis B virus (HBV)/ hepatitis C virus (HCV) infection. To overcome the problem, we have developed a new multiphasic model in which the immune system activity is modulated by a negative feedback caused by the infected cells reduction, and alanine aminotransferase kinetics serve as a surrogate marker of infected-cell clearance. By this approach, we can compute the dynamics of infected cells during the whole treatment course, and find a good correlation between the number of infected cells at the end of therapy and the long-term virological response in patients with chronic hepatitis C. The new model successfully describes the HBV infection dynamics far beyond the third month of antiviral therapy under the assumption that the sum of infected and non-infected cells remains roughly constant during therapy, and both target and infected cells concur in the hepatocyte turnover. In clinical practice, these new models will allow the development of simulators of treatment response that will be used as an "automatic pilot" for tailoring antiviral therapy in chronic hepatitis B as well as chronic hepatitis C patients.

  10. Bio-mathematical models of viral dynamics to tailor antiviral therapy in chronic viral hepatitis

    Science.gov (United States)

    Brunetto, Maurizia Rossana; Colombatto, Piero; Bonino, Ferruccio

    2009-01-01

    The simulation of the dynamics of viral infections by mathematical equations has been applied successfully to the study of viral infections during antiviral therapy. Standard models applied to viral hepatitis describe the viral load decline in the first 2-4 wk of antiviral therapy, but do not adequately simulate the dynamics of viral infection for the following period. The hypothesis of a constant clearance rate of the infected cells provides an unrealistic estimation of the time necessary to reach the control or the clearance of hepatitis B virus (HBV)/hepatitis C virus (HCV) infection. To overcome the problem, we have developed a new multiphasic model in which the immune system activity is modulated by a negative feedback caused by the infected cells reduction, and alanine aminotransferase kinetics serve as a surrogate marker of infected-cell clearance. By this approach, we can compute the dynamics of infected cells during the whole treatment course, and find a good correlation between the number of infected cells at the end of therapy and the long-term virological response in patients with chronic hepatitis C. The new model successfully describes the HBV infection dynamics far beyond the third month of antiviral therapy under the assumption that the sum of infected and non-infected cells remains roughly constant during therapy, and both target and infected cells concur in the hepatocyte turnover. In clinical practice, these new models will allow the development of simulators of treatment response that will be used as an “automatic pilot” for tailoring antiviral therapy in chronic hepatitis B as well as chronic hepatitis C patients. PMID:19195054

  11. Critical role of an antiviral stress granule containing RIG-I and PKR in viral detection and innate immunity.

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    Koji Onomoto

    Full Text Available Retinoic acid inducible gene I (RIG-I-like receptors (RLRs function as cytoplasmic sensors for viral RNA to initiate antiviral responses including type I interferon (IFN production. It has been unclear how RIG-I encounters and senses viral RNA. To address this issue, we examined intracellular localization of RIG-I in response to viral infection using newly generated anti-RIG-I antibody. Immunohistochemical analysis revealed that RLRs localized in virus-induced granules containing stress granule (SG markers together with viral RNA and antiviral proteins. Because of similarity in morphology and components, we termed these aggregates antiviral stress granules (avSGs. Influenza A virus (IAV deficient in non-structural protein 1 (NS1 efficiently generated avSGs as well as IFN, however IAV encoding NS1 produced little. Inhibition of avSGs formation by removal of either the SG component or double-stranded RNA (dsRNA-dependent protein kinase (PKR resulted in diminished IFN production and concomitant enhancement of viral replication. Furthermore, we observed that transfection of dsRNA resulted in IFN production in an avSGs-dependent manner. These results strongly suggest that the avSG is the locus for non-self RNA sensing and the orchestration of multiple proteins is critical in the triggering of antiviral responses.

  12. UNC93B1 mediates innate inflammation and antiviral defense in the liver during acute murine cytomegalovirus infection.

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    Meredith J Crane

    Full Text Available Antiviral defense in the liver during acute infection with the hepatotropic virus murine cytomegalovirus (MCMV involves complex cytokine and cellular interactions. However, the mechanism of viral sensing in the liver that promotes these cytokine and cellular responses has remained unclear. Studies here were undertaken to investigate the role of nucleic acid-sensing Toll-like receptors (TLRs in initiating antiviral immunity in the liver during infection with MCMV. We examined the host response of UNC93B1 mutant mice, which do not signal properly through TLR3, TLR7 and TLR9, to acute MCMV infection to determine whether liver antiviral defense depends on signaling through these molecules. Infection of UNC93B1 mutant mice revealed reduced production of systemic and liver proinflammatory cytokines including IFN-α, IFN-γ, IL-12 and TNF-α when compared to wild-type. UNC93B1 deficiency also contributed to a transient hepatitis later in acute infection, evidenced by augmented liver pathology and elevated systemic alanine aminotransferase levels. Moreover, viral clearance was impaired in UNC93B1 mutant mice, despite intact virus-specific CD8+ T cell responses in the liver. Altogether, these results suggest a combined role for nucleic acid-sensing TLRs in promoting early liver antiviral defense during MCMV infection.

  13. Bacteria, fungi and arthropod pests collected on modern human mummies

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    F. Palla

    2011-08-01

    Full Text Available A survey of opportunistic biocenosis (macro and micro organisms associated with a rest of human mummy samples was carried out to characterise the biocenosis and to detect the potential of biodeteriogens. The rests of the human modern mummies come from a hypogeic site. Since mummies are relevant from a historic-artistic-scientific point of view, an aspect of this study was the identification and characterization of the biological systems related with biodeterioration of organic matter. In a first step, different sampling methods, according to the taxa, were applied. Technological procedures were combined in order to have an interdisciplinary approach to the conservation actions for testing future restoration protocols. Specimens were collected, identified and characterized by Microscopy (light, SEM, CLSM and molecular analyses (DNA extraction, in vitro target sequence amplification, sequencing, sequence analysis. The results highlight a rather complex biocenonsis consisting of fungi, cyanobacteria, several insects and other arthropods.

  14. Phenoptosis in arthropods and immortality of social insects.

    Science.gov (United States)

    Kartsev, V M

    2014-10-01

    In general, there are no drastic differences in phenoptosis patterns in plant and animal organisms. However, there are some specific features characteristic for insects and other arthropods: 1) their development includes metamorphosis with different biochemical laws at consecutive developmental stages; 2) arthropods can reduce or stop development and aging when in a state of diapause or temporal cold immobility; 3) their life cycle often correlates with seasonal changes of surroundings; 4) polymorphism is widespread - conspecifics differ by their lifespans and phenoptosis features; 5) lifespan-related sexual dimorphism is common; 6) significant situational plasticity of life cycle organization is an important feature; for example, the German wasp (Paravespula germanica) is obligatorily univoltine in the temperate zone, while in tropical regions its lifespan increases and leads to repeated reproduction; 7) life cycles of closely related species may differ significantly, for example, in contrast to German wasp, some tropical hornets (Vespa) have only one reproduction period. Surprisingly, many insect species have been shown to be subjected to gradual aging and phenoptosis, like the highest mammals. However, queens of social insects and some long-lived arachnids can apparently be considered non-aging organisms. In some species, lifespan is limited to one season, while others live much longer or shorter. Cases of one-time reproduction are rather rare. Aphagia is common in insects (over 10,000 species). Cannibalism is an important mortality factor in insects as well as in spiders. In social insects, which exist only in colonies (families), the lifetime of a colony can be virtually unlimited. However, in case of some species the developmental cycle and death of a colony after its completion are predetermined. Most likely, natural selection in insects does not lengthen individual lifespan, but favors increase in reproduction efficiency based on fast succession of

  15. Phenoptosis in arthropods and immortality of social insects.

    Science.gov (United States)

    Kartsev, V M

    2014-10-01

    In general, there are no drastic differences in phenoptosis patterns in plant and animal organisms. However, there are some specific features characteristic for insects and other arthropods: 1) their development includes metamorphosis with different biochemical laws at consecutive developmental stages; 2) arthropods can reduce or stop development and aging when in a state of diapause or temporal cold immobility; 3) their life cycle often correlates with seasonal changes of surroundings; 4) polymorphism is widespread - conspecifics differ by their lifespans and phenoptosis features; 5) lifespan-related sexual dimorphism is common; 6) significant situational plasticity of life cycle organization is an important feature; for example, the German wasp (Paravespula germanica) is obligatorily univoltine in the temperate zone, while in tropical regions its lifespan increases and leads to repeated reproduction; 7) life cycles of closely related species may differ significantly, for example, in contrast to German wasp, some tropical hornets (Vespa) have only one reproduction period. Surprisingly, many insect species have been shown to be subjected to gradual aging and phenoptosis, like the highest mammals. However, queens of social insects and some long-lived arachnids can apparently be considered non-aging organisms. In some species, lifespan is limited to one season, while others live much longer or shorter. Cases of one-time reproduction are rather rare. Aphagia is common in insects (over 10,000 species). Cannibalism is an important mortality factor in insects as well as in spiders. In social insects, which exist only in colonies (families), the lifetime of a colony can be virtually unlimited. However, in case of some species the developmental cycle and death of a colony after its completion are predetermined. Most likely, natural selection in insects does not lengthen individual lifespan, but favors increase in reproduction efficiency based on fast succession of

  16. New insights on arthropod toxins that potentiate erectile function.

    Science.gov (United States)

    Nunes, Kenia P; Torres, Fernanda S; Borges, Marcia H; Matavel, Alessandra; Pimenta, Adriano M C; De Lima, Maria E

    2013-07-01

    The use of natural substances for the treatment of diseases or injuries is an ancient practice of many cultures. According to folklore, natural aphrodisiacs may help to raise libido and increase desire. The supposed aphrodisiacs mainly include a plethora of preparations of plants, among other substances. However, the real boundary between myth and reality has not been established yet in most cases and such boundaries must be drawn by scientific methods. A growing interest of the scientific community has been focused on animal venoms, especially those from arthropods, i.e. spiders and scorpions, which cause priapism, a prolonged and painful erection. This review highlights the studies that have been performed with venoms and toxins from arthropods known to cause priapism, among other toxic symptoms, pointing out some pharmacological approaches for better understanding this effect. To date, the venom of some spiders, mainly Phoneutria nigriventer, and scorpions, such as the yellow South American scorpion Tityus serrulatus, among others, have been known to cause priapism. Since erectile dysfunction (ED) is a growing health problem in the world, more common in patients with vascular diseases as diabetes and hypertension, the use of animal venoms and toxins as pharmacological tools could not only shed light to the mechanisms involved in erectile function, but also represent a possible model for new drugs to treat ED. Unfortunately, attempts to correlate the structure of those priapism-related toxins were unfruitful. Such difficulties lie firstly on the poor data concerning purified priapism-related toxins, instead of whole venoms and/or semi-purified fractions, and secondly, on the scarce available primary sequences and structural data, mainly from spider toxins. It has been shown that all these toxins modify the sodium (Na(+)) channel activity, mostly slowing down its inactivation current. Improving the knowledge on the tertiary structure of these toxins could provide

  17. A systematic review of arthropod community diversity in association with invasive plants

    Directory of Open Access Journals (Sweden)

    Ryan Spafford

    2013-04-01

    Full Text Available Invasive plants represent a significant financial burden for land managers and also have the potential to severely degrade ecosystems. Arthropods interact strongly with plants, relying on them for food, shelter, and as nurseries for their young. For these reasons, the impacts of plant invasions are likely strongly reflected by arthropod community dynamics including diversity and abundances. A systematic review was conducted to ascertain the state of the literature with respect to plant invaders and their associated arthropod communities. We found that the majority of studies did not biogeographically contrast arthropod community dynamics from both the home and away ranges and that studies were typically narrow in scope, focusing only on the herbivore feeding guild, rather than assessing two or more trophic levels. Importantly, relative arthropod richness was significantly reduced on invasive plant species. Phylogenetic differences between the invasive and local plant community as well as the plant functional group impact arthropod diversity patterns. A framework highlighting some interaction mechanisms between multiple arthropod trophic levels and native and invasive plants is discussed and future research directions relating to these interactions and the findings herein are proposed.

  18. Arthropod abundance and seasonal bird use of bottomland forest harvest gaps.

    Energy Technology Data Exchange (ETDEWEB)

    Moorman, Christopher, E.; Bowen, Liessa T.; Kilgo, John, C.; Hanula, James, L.; Horn, Scott; Ulyshen, Michael, D.

    2012-03-01

    We investigated the influence of arthropod abundance and vegetation structure on shifts in avian use of canopy gap, gap edge, and surrounding forest understory in a bottomland hardwood forest in the Upper Coastal Plain of South Carolina. We compared captures of foliage-gleaning birds among locations during four periods (spring migration, breeding, post-breeding, and fall migration). Foliage arthropod densities were greatest in the forest understory in all four seasons, but understory vegetation density was greatest in gaps. Foliage-gleaning bird abundance was positively associated with foliage-dwelling arthropods during the breeding (F = 18.5, P < 0.001) and post-breeding periods (F = 9.4, P = 0.004), and negatively associated with foliage-dwelling arthropods during fall migration (F = 5.4, P = 0.03). Relationships between birds and arthropods were inconsistent, but the arthropod prey base seemed to be least important during migratory periods. Conversely, bird captures were positively correlated with understory vegetation density during all four periods (P < 0.001). Our study suggests high bird abundance associated with canopy gaps during the non-breeding period resulted less from high arthropod food resource availability than from complex understory and midstory vegetation structure.

  19. Acquisition of Cry1Ac protein by non-target arthropods in Bt soybean fields.

    Science.gov (United States)

    Yu, Huilin; Romeis, Jörg; Li, Yunhe; Li, Xiangju; Wu, Kongming

    2014-01-01

    Soybean tissue and arthropods were collected in Bt soybean fields in China at different times during the growing season to investigate the exposure of arthropods to the plant-produced Cry1Ac toxin and the transmission of the toxin within the food web. Samples from 52 arthropod species/taxa belonging to 42 families in 10 orders were analysed for their Cry1Ac content using enzyme-linked immunosorbent assay (ELISA). Among the 22 species/taxa for which three samples were analysed, toxin concentration was highest in the grasshopper Atractomorpha sinensis and represented about 50% of the concentration in soybean leaves. Other species/taxa did not contain detectable toxin or contained a concentration that was between 1 and 10% of that detected in leaves. These Cry1Ac-positive arthropods included a number of mesophyll-feeding Hemiptera, a cicadellid, a curculionid beetle and, among the predators, a thomisid spider and an unidentified predatory bug belonging to the Anthocoridae. Within an arthropod species/taxon, the Cry1Ac content sometimes varied between life stages (nymphs/larvae vs. adults) and sampling dates (before, during, and after flowering). Our study is the first to provide information on Cry1Ac-expression levels in soybean plants and Cry1Ac concentrations in non-target arthropods in Chinese soybean fields. The data will be useful for assessing the risk of non-target arthropod exposure to Cry1Ac in soybean.

  20. Effects of persistent insecticides on beneficial soil arthropod in conventional fields compared to organic fields, puducherry.

    Science.gov (United States)

    Anbarashan, Padmavathy; Gopalswamy, Poyyamoli

    2013-07-15

    The usage of synthetic fertilizers/insecticides in conventional farming has dramatically increased over the past decades. The aim of the study was to compare the effects of bio-pesticides and insecticides/pesticides on selected beneficial non targeted arthropods. Orders Collembola, Arachinida/Opiliones, Oribatida and Coleoptera were the main groups of arthropods found in the organic fields and Coleoptera, Oribatida, Gamasida and Collembola in conventional fields. Pesticides/insecticides had a significant effect on non-targeted arthropods order- Collembola, Arachinida/Opiliones, Hymenoptera and Thysonoptera were suppressed after pesticides/insecticides spraying. Bio-insecticides in organic fields had a non-significant effect on non targeted species and they started to increase in abundance after 7 days of spraying, whereas insecticide treatment in conventional fields had a significant long-term effect on non targeted arthropods and short term effect on pests/insects, it started to increase after 21 days of the spraying. These results indicate that insecticide treatment kept non targeted arthropods at low abundance. In conclusion, organic farming does not significantly affected the beneficial-non targeted arthropods biodiversity, whereas preventive insecticide application in conventional fields had significant negative effects on beneficial non targeted arthropods. Therefore, conventional farmers should restrict insecticide applications, unless pest densities reach the thresholds and more desirably can switch to organic farming practices.

  1. Acquisition of Cry1Ac protein by non-target arthropods in Bt soybean fields.

    Directory of Open Access Journals (Sweden)

    Huilin Yu

    Full Text Available Soybean tissue and arthropods were collected in Bt soybean fields in China at different times during the growing season to investigate the exposure of arthropods to the plant-produced Cry1Ac toxin and the transmission of the toxin within the food web. Samples from 52 arthropod species/taxa belonging to 42 families in 10 orders were analysed for their Cry1Ac content using enzyme-linked immunosorbent assay (ELISA. Among the 22 species/taxa for which three samples were analysed, toxin concentration was highest in the grasshopper Atractomorpha sinensis and represented about 50% of the concentration in soybean leaves. Other species/taxa did not contain detectable toxin or contained a concentration that was between 1 and 10% of that detected in leaves. These Cry1Ac-positive arthropods included a number of mesophyll-feeding Hemiptera, a cicadellid, a curculionid beetle and, among the predators, a thomisid spider and an unidentified predatory bug belonging to the Anthocoridae. Within an arthropod species/taxon, the Cry1Ac content sometimes varied between life stages (nymphs/larvae vs. adults and sampling dates (before, during, and after flowering. Our study is the first to provide information on Cry1Ac-expression levels in soybean plants and Cry1Ac concentrations in non-target arthropods in Chinese soybean fields. The data will be useful for assessing the risk of non-target arthropod exposure to Cry1Ac in soybean.

  2. Aerial arthropod communities of native and invaded forests, Robinson Crusoe Island, Chile.

    Science.gov (United States)

    Hagen, Erin N; Bakker, Jonathan D; Gara, Robert I

    2010-08-01

    Invasive species significantly contribute to biological change and threaten biodiversity, with a growing body of evidence that plant invasions affect higher trophic levels. We explored the relative importance of plant invasion and forest structure on aerial arthropod abundance, diversity, and composition on Robinson Crusoe Island, Chile. We used flight intercept traps to sample aerial arthropods within distinct canopy strata of native and invaded forests over 3-mo periods in 2006 and 2007. Arthropod abundance and diversity were higher in native than invaded forest, and arthropod communities were distinct between forest types. In both forest types, arthropod abundance was highest in the lower canopy, and canopy strata exhibited some differences in arthropod community composition. Several morphospecies were distinctly associated with each forest type. The strong differences in aerial arthropod communities associated with the invasion of native forest by non-native plants may affect other trophic levels, such as insectivorous birds. Steps to stop invasive plant spread and to restore native forest composition and structure are needed to safeguard the integrity of native communities, from plants to higher-level consumers.

  3. Simulating small-scale climate change effects-lessons from a short-term field manipulation experiment on grassland arthropods.

    Science.gov (United States)

    Buchholz, Sascha; Rolfsmeyer, Dorothee; Schirmel, Jens

    2013-10-01

    Climate change is expected to cause major consequences on biodiversity. Understanding species-specific reactions, such as species shifts, species declines, and changes in population dynamics is a key issue to quantify large-scale impacts of climate change on biotic communities. As it is often impossible or at least impracticable to conduct large-scale experiments on biotic responses to climate change, studies at a smaller scale may be a useful alternative. In our study, we therefore tested responses of grassland arthropods (carabid beetles, spiders, grasshoppers) to simulated climate change in terms of species activity densities and diversity. We conducted a controlled field experiment by changing water and microclimatic conditions at a small scale (16 m(2) ). Roof constructions were used to increase drought-like conditions, whereas water supply was enhanced by irrigation. In all, 2 038 carabid beetles (36 species), 4 893 spiders (65 species), and 303 Orthoptera (4 species) were caught using pitfall traps from May to August, 2010. During our experiment, we created an artificial small-scale climate change; and statistics revealed that these changes had short-term effects on the total number of individuals and Simpson diversity of the studied arthropod groups. Moreover, our results showed that certain species might react very quickly to climate change in terms of activity densities, which in turn might influence diversity due to shifts in abundance patterns. Finally, we devised methodological improvements that may further enhance the validity of future studies. PMID:23956202

  4. Arthropods of Medical Importance in Brazil: Retrospective Epidemiological Information about Accidents Involving these Animals

    Directory of Open Access Journals (Sweden)

    Danon Clemes Cardoso

    2009-01-01

    Full Text Available Problem statement: The epidemiological information about arthropods bites/sting in Criciúma region no was reported. The aim of this Research was to draw the epidemiologic profile of accidents with arthropods in Criciúma region. Approach: The information regarding accidents with arthropods from 1994-2006 was prospectively collected from SINAN (System of Injury Notification Information files of the 21a Municipal Health Secretary of Criciúma region. Was calculated the frequency for each variable studied and incidence coefficient for period of study. Results: Results were recorded 1821 notifications of accidents with arthropods in region studied. The numbers of occurrence increased along of the years studied. The arthropod that most result in accidents was the spider with 1,126 (75.9% cases followed by Honeybees and others Arthropods with 149 (10.0% cases, Caterpillars including Lonomia genus and others genera (54/3.7% and scorpions with the least number of accidents with 6 (0.4% cases. The incidence of accidents every thousand inhabitants had a significant increase starting in the year of 2000. The majority of accidents occurred in the warmest months, increasing in the spring and summer seasons. Was recorded more than twice of accidents with arthropods in Urban area than in rural areas. The Chi-square test revealed that the frequency of accidents between locations and type of arthropods is different. Likewise, the number the victims and activity type in moment of the bite/sting had been a differ behavior between arthropods type. However, the number of accidents involving victims of male and female gender is equal. Conclusion: Epidemiological studies of this type in the extreme south of Santa Catarina are scarce. Only few studies have reported the patterns of occurrence and incidence of accidents with poisonous animals. These and other studies are of great importance for implementation of measures mitigation programs and education for

  5. Sweeping beauty: is grassland arthropod community composition effectively estimated by sweep netting?

    Science.gov (United States)

    Spafford, Ryan D; Lortie, Christopher J

    2013-01-01

    Arthropods are critical ecosystem components due to their high diversity and sensitivity to perturbation. Furthermore, due to their ease of capture they are often the focus of environmental health surveys. There is much debate regarding the best sampling method to use in these surveys. Sweep netting and pan trapping are two sampling methods commonly used in agricultural arthropod surveys, but have not been contrasted in natural grassland systems at the community level. The purpose of this study was to determine whether sweep netting was effective at estimating arthropod diversity at the community level in grasslands or if supplemental pan trapping was needed. Arthropods were collected from grassland sites in Montana, USA, in the summer of 2011. The following three standardized evaluation criteria (consistency, reliability, and precision) were developed to assess the efficacy of sweep netting and pan trapping, based on analyses of variations in arthropod abundances, species richness, evenness, capture frequency, and community composition. Neither sampling method was sufficient in any criteria to be used alone for community-level arthropod surveys. On a taxa-specific basis, however, sweep netting was consistent, reliable, and precise for Thysanoptera, infrequently collected (i.e., rare) insects, and Arachnida, whereas pan trapping was consistent, reliable, and precise for Collembola and bees, which is especially significant given current threats to the latter's populations worldwide. Species-level identifications increase the detected dissimilarity between sweep netting and pan trapping. We recommend that community-level arthropod surveys use both sampling methods concurrently, at least in grasslands, but likely in most nonagricultural systems. Target surveys, such as monitoring bee communities in fragmented grassland habitat or where detailed information on behavior of the target arthropod groups is available can in some instances employ singular methods. As a

  6. Dengue Virus Entry as Target for Antiviral Therapy

    Directory of Open Access Journals (Sweden)

    Marijke M. F. Alen

    2012-01-01

    Full Text Available Dengue virus (DENV infections are expanding worldwide and, because of the lack of a vaccine, the search for antiviral products is imperative. Four serotypes of DENV are described and they all cause a similar disease outcome. It would be interesting to develop an antiviral product that can interact with all four serotypes, prevent host cell infection and subsequent immune activation. DENV entry is thus an interesting target for antiviral therapy. DENV enters the host cell through receptor-mediated endocytosis. Several cellular receptors have been proposed, and DC-SIGN, present on dendritic cells, is considered as the most important DENV receptor until now. Because DENV entry is a target for antiviral therapy, various classes of compounds have been investigated to inhibit this process. In this paper, an overview is given of all the putative DENV receptors, and the most promising DENV entry inhibitors are discussed.

  7. STUDY OF ANTIVIRAL ACTIVITY OF SOME HYDRAZONE PINOSTROBIN DERIVATIVES

    Directory of Open Access Journals (Sweden)

    G. K. Mukusheva

    2014-01-01

    Full Text Available New derivatives on the basis of hydrazone pinostrobin molecule were synthesized. Significant antiviral activity of received samples of new hydrazone pinstrobin derivatives was identified.

  8. Longleaf Pine Characterists Associated with Arthropods Available for Red-Cockaded Woodpeckers

    Energy Technology Data Exchange (ETDEWEB)

    Hanula, J.L.; Franzreb, K.E.; Pepper, W.D.

    1999-01-25

    The authors sampled arthropods on 300 longleaf pine under varying stand conditions and ranging in age from 20 to 100 years. The most diverse orders were beetles, spiders, ants, wasps and bees. The most abundant were aphids and Hymenoptera with a large number of ants. Arthropod biomass per tree increased in age up to 65-70 years, but biomass was highest in the youngest stands. Arthropods were positively correlated to bark thickness and tree diameter, but negatively related to the stand basal area. No relationships were found between abundance and ground vegetation conditions.

  9. Acquisition of Cry1Ac Protein by Non-Target Arthropods in Bt Soybean Fields

    OpenAIRE

    Huilin Yu; Jörg Romeis; Yunhe Li; Xiangju Li; Kongming Wu

    2014-01-01

    Soybean tissue and arthropods were collected in Bt soybean fields in China at different times during the growing season to investigate the exposure of arthropods to the plant-produced Cry1Ac toxin and the transmission of the toxin within the food web. Samples from 52 arthropod species/taxa belonging to 42 families in 10 orders were analysed for their Cry1Ac content using enzyme-linked immunosorbent assay (ELISA). Among the 22 species/taxa for which three samples were analysed, toxin concentra...

  10. Antiviral Efficacy and Host Innate Immunity Associated with SB 9200 Treatment in the Woodchuck Model of Chronic Hepatitis B

    Science.gov (United States)

    Korolowicz, Kyle E.; Iyer, Radhakrishnan P.; Czerwinski, Stefanie; Suresh, Manasa; Yang, Junming; Padmanabhan, Seetharamaiyer; Sheri, Anjaneyulu; Pandey, Rajendra K.; Skell, Jeffrey; Marquis, Judith K.; Kallakury, Bhaskar V.; Tucker, Robin D.; Menne, Stephan

    2016-01-01

    SB 9200, an oral prodrug of the dinucleotide SB 9000, is being developed for the treatment of chronic hepatitis B virus (HBV) infection and represents a novel class of antivirals. SB 9200 is thought to activate the viral sensor proteins, retinoic acid-inducible gene 1 (RIG-I) and nucleotide-binding oligomerization domain-containing protein 2 (NOD2) resulting in interferon (IFN) mediated antiviral immune responses in virus-infected cells. Additionally, the binding of SB 9200 to these sensor proteins could also sterically block the ability of the viral polymerase to access pre-genomic RNA for nucleic acid synthesis. The immune stimulating and direct antiviral properties of SB 9200 were evaluated in woodchucks chronically infected with woodchuck hepatitis virus (WHV) by daily, oral dosing at 15 and 30 mg/kg for 12 weeks. Prolonged treatment resulted in 2.2 and 3.7 log10 reductions in serum WHV DNA and in 0.5 and 1.6 log10 declines in serum WHV surface antigen from pretreatment level with the lower or higher dose of SB 9200, respectively. SB 9200 treatment also resulted in lower hepatic levels of WHV nucleic acids and antigen and reduced liver inflammation. Following treatment cessation, recrudescence of viral replication was observed but with dose-dependent delays in viral relapse. The antiviral effects were associated with dose-dependent and long-lasting induction of IFN-α, IFN-β and IFN-stimulated genes in blood and liver, which correlated with the prolonged activation of the RIG-I/NOD2 pathway and hepatic presence of elevated RIG-I protein levels. These results suggest that in addition to a direct antiviral activity, SB 9200 induces antiviral immunity during chronic hepadnaviral infection via activation of the viral sensor pathway. PMID:27552102

  11. L-Valine Ester of Cyclopropavir - a New Antiviral Prodrug

    OpenAIRE

    Wu, Zhimeng; Drach, John C.; Prichard, Mark N.; Yanachkova, Milka; Yanachkov, Ivan; Bowlin, Terry L.; Zemlicka, Jiri

    2009-01-01

    The L-Valine ester of antiviral agent cyclopropavir, valcyclopropavir (6), was synthesized and evaluated for antiviral properties. Prodrug (6) inhibited replication of HCMV virus (Towne and AD169 strain) in HFF cells to approximately the same extent as the parent drug cyclopropavir (5). Stability of 6 toward hydrolysis at pH 7.0 roughly corresponds to that of valganciclovir (2). Pharmacokinetic studies in mice established that the oral bioavailability of valcyclopropavir (6) was 95%.

  12. RNA interference: Antiviral weapon and beyond

    Institute of Scientific and Technical Information of China (English)

    Quan-Chu Wang; Qing-He Nie; Zhi-Hua Feng

    2003-01-01

    RNA interference (RNAi) is a remarkable type of gene regulation based on sequence-specific targeting and degradation of RNA. The term encompasses related pathways found in a broad range of eukaryotic organisms, including fungi, plants, and animals. RNA interference is part of a sophisticated network of interconnected pathways for cellular defense, RNA surveillance, and development and it may become a powerful tool to manipulate gene expression experimentally. RNAi technology is currently being evaluated not only as an extremely powerful instrument for functional genomic analyses, but also as a potentially useful method to develop specific dsRNA based gene-silencing therapeutics.Several laboratories have been interested in using RNAi to control viral infection and many reports in Nature and in Cell show that short interfering (si) RNAs can inhibit infection by HIV-1, polio and hepatitis C viruses in a sequence-specific manner. RNA-based strategies for gene inhibition in mammalian cells have recently been described, which offer the promise of antiviral therapy.

  13. Antiviral Warrior-APOBEC3G

    Institute of Scientific and Technical Information of China (English)

    WU Xiao-xia; MA Yi-cai

    2005-01-01

    This paper is to further understand how APOBEC3G can defend the retroviruses and to find new approaches to AIDs (acquired immure deficiency syndrome).The viral infectivity factor (Vif) induces rapid degradation of APOBEC3G by ubiquitination, which is a proteosome-dependent pathway. Precisely speaking, only in the virus-producing cell Vif expression is necessary; in its absence, infection of a subsequent target cell terminates at a postentry step through the action of the human APOBEC3G antiviral mechanism. Vif protein has two domains: one binds to APOBEC3G and the other regulates the degradation of APOBEC3G by a conserved sequence, SLQ (Y/F) LA motif. Recently, the research on Vif has also revealed APOBEC3G is a novel component of innate immune system. In fact, APOBEC3G not only acts in DNA editing to block the replication of retroviruses such as HIV-1, but also is able to defend a wide spectrum of distantly related retroviruses and interferes with HBV through a different mechanism from HIV.

  14. ANTIVIRAL POTENTIAL OF MEDICINAL PLANTS: AN OVERVIEW

    Directory of Open Access Journals (Sweden)

    Ruwali Pushpa

    2013-06-01

    Full Text Available The term ‘Antiviral agents’ has been defined in very broad terms as substances other than a virus or virus containing vaccine or specific antibody which can produce either a protective or therapeutic effect to the clear detectable advantage of the virus infected host. The herbal medicine has a long traditional use and the major advantage over other medicines is their wide therapeutic window with rare side effects. There are some disadvantages of synthetic drugs like narrow therapeutic window and more importantly the various adverse side effects which occur quite frequently. Due to these disadvantages and other limitations, there is an increasing trend in the field of research for discovering new and noble drugs based on various herbal formulations. This review attempts to address the importance of developing therapeutic herbal formulations from various medicinal plants using the knowledge based on traditional system of medicines, the Ayurveda. Although natural products have been used by civilization since ancient times, only in recent decades has there been growing research into alternative therapies and the therapeutics use of natural products, especially those derived from plants. Plants synthesize and preserve a variety of biochemical products, many of which are extractable and used for various scientific investigations. Therefore, medicinal plants proved to be a major resort for the treatment of diseases and sicknesses by traditional healers in many societies.

  15. Ribozymes:an anti-viral agent

    Institute of Scientific and Technical Information of China (English)

    Asad U.Khan; Shahper N.Khan

    2008-01-01

    The discovery that RNA can act as an enzyme led Thomas Cech to win the Nobel Prize in Chemistry and led immediately to the next wave of attempts to find an effective RNA-based therapy.The tantalizing idea that RNA enzymes called trans-cleaving ribozymes enables them to act as potential antiviral and powerful tool for functional genomic studies.The efficacy of ribozyme function in a complex intracellular environment is depend-ent on the intracellular fate of the RNA that is being targeted.Recently,ribozymes have been used successfully to inhibit gene expression in a variety of biological systems in vitro and in vivo.Ribozyme has also been used successfully to combat many cases of viral infection,as clinical trial.Despite it needs to be investigated and explored as far as its structural and functional aspects are concern.In view of the significance of ribozyme in modern medicine,we reviewed the recent literature on general approach to control viral infection.

  16. Perspective of Use of Antiviral Peptides against Influenza Virus.

    Science.gov (United States)

    Skalickova, Sylvie; Heger, Zbynek; Krejcova, Ludmila; Pekarik, Vladimir; Bastl, Karel; Janda, Jozef; Kostolansky, Frantisek; Vareckova, Eva; Zitka, Ondrej; Adam, Vojtech; Kizek, Rene

    2015-10-01

    The threat of a worldwide influenza pandemic has greatly increased over the past decade with the emergence of highly virulent avian influenza strains. The increased frequency of drug-resistant influenza strains against currently available antiviral drugs requires urgent development of new strategies for antiviral therapy, too. The research in the field of therapeutic peptides began to develop extensively in the second half of the 20(th) century. Since then, the mechanisms of action for several peptides and their antiviral prospect received large attention due to the global threat posed by viruses. Here, we discussed the therapeutic properties of peptides used in influenza treatment. Peptides with antiviral activity against influenza can be divided into three main groups. First, entry blocker peptides such as a Flupep that interact with influenza hemagglutinin, block its binding to host cells and prevent viral fusion. Second, several peptides display virucidal activity, disrupting viral envelopes, e.g., Melittin. Finally, a third set of peptides interacts with the viral polymerase complex and act as viral replication inhibitors such as PB1 derived peptides. Here, we present a review of the current literature describing the antiviral activity, mechanism and future therapeutic potential of these influenza antiviral peptides. PMID:26492266

  17. Perspective of Use of Antiviral Peptides against Influenza Virus

    Directory of Open Access Journals (Sweden)

    Sylvie Skalickova

    2015-10-01

    Full Text Available The threat of a worldwide influenza pandemic has greatly increased over the past decade with the emergence of highly virulent avian influenza strains. The increased frequency of drug-resistant influenza strains against currently available antiviral drugs requires urgent development of new strategies for antiviral therapy, too. The research in the field of therapeutic peptides began to develop extensively in the second half of the 20th century. Since then, the mechanisms of action for several peptides and their antiviral prospect received large attention due to the global threat posed by viruses. Here, we discussed the therapeutic properties of peptides used in influenza treatment. Peptides with antiviral activity against influenza can be divided into three main groups. First, entry blocker peptides such as a Flupep that interact with influenza hemagglutinin, block its binding to host cells and prevent viral fusion. Second, several peptides display virucidal activity, disrupting viral envelopes, e.g., Melittin. Finally, a third set of peptides interacts with the viral polymerase complex and act as viral replication inhibitors such as PB1 derived peptides. Here, we present a review of the current literature describing the antiviral activity, mechanism and future therapeutic potential of these influenza antiviral peptides.

  18. Dancing with chemical formulae of antivirals: A panoramic view (Part 2).

    Science.gov (United States)

    De Clercq, Erik

    2013-11-15

    In this second part of "Dancing with antivirals as chemical formulae" I will focus on a number of chemical compounds that in the last few years have elicited more than common attraction from a commercial viewpoint: (i) favipiravir (T-705), as it is active against influenza, but also several other RNA viruses; (ii) neuraminidase inhibitors such as zanamivir and oseltamivir; (iii) peramivir and laninamivir octanoate, which might be effective against influenza virus following a single (intravenous or inhalation) administration; (iv) sofosbuvir, the (anticipated) cornerstone for the interferon-free therapy of HCV infections; (v) combinations of DAAs (direct antiviral agents) to achieve, in no time, a sustained virus response (SVR) against HCV infection; (vi) HIV protease inhibitors, the latest and most promising being darunavir; (vii) the integrase inhibitors (INIs) (raltegravir, elvitegravir, dolutegravir), representing a new dimension in the anti-HIV armamentarium; (viii), a new class of helicase primase inhibitors (HPIs) that may exceed acyclovir and the other anti-herpes compounds in both potency and safety; (ix) CMX-001, as the latest of Dr. Antonín Holý's legacy for its activity against poxviruses and CMV infections, and (x) noroviruses for which the ideal antiviral compounds are still awaited for. PMID:24070654

  19. Antiviral therapy for chronic hepatitis B: Combination of nucleoside analogs and interferon

    Institute of Scientific and Technical Information of China (English)

    Satoru; Hagiwara; Naoshi; Nishida; Masatoshi; Kudo

    2015-01-01

    The ideal goal of chronic hepatitis B(CHB) treatment should be suppression of emergence of hepatocellular carcinoma through the disappearance of hepatitis B s antigen(HBs Ag) rather than the control of serum hepatitis B virus-DNA level. For this purpose, various types of combination therapies using nucleoside analogs(NAs) and interferon(IFN) have been conducted. The therapeutic effects of combination of two different kinds of agents are better than those of the monotherapy using NAs or IFN alone, probably because different pharmaceutical properties might act in a coordinated manner. Recently, combination therapies with NAs and IFN and sequential therapies with NAs administration followed by IFN therapy have been routinely employed. We previously reported that combination therapy using entecavir(ETV) and pegylated(PEG)-IFN showed antiviral effects in 71% of CHB patients; the effect of this combination was better than that using lamivudine(LAM) and PEG-IFN. This is partially explained by the better antiviral effects of ETV than those of LAM. In our analysis, the cohort of CHB consisted of the patients who showed a flare-up of hepatitis before antiviral therapy, and their baseline HBs Ag levels were relatively low. Therefore, in addition to the combination of the agents, the appropriate selection of patients is critical to achieve a good viral response.

  20. Dancing with chemical formulae of antivirals: A panoramic view (Part 2).

    Science.gov (United States)

    De Clercq, Erik

    2013-11-15

    In this second part of "Dancing with antivirals as chemical formulae" I will focus on a number of chemical compounds that in the last few years have elicited more than common attraction from a commercial viewpoint: (i) favipiravir (T-705), as it is active against influenza, but also several other RNA viruses; (ii) neuraminidase inhibitors such as zanamivir and oseltamivir; (iii) peramivir and laninamivir octanoate, which might be effective against influenza virus following a single (intravenous or inhalation) administration; (iv) sofosbuvir, the (anticipated) cornerstone for the interferon-free therapy of HCV infections; (v) combinations of DAAs (direct antiviral agents) to achieve, in no time, a sustained virus response (SVR) against HCV infection; (vi) HIV protease inhibitors, the latest and most promising being darunavir; (vii) the integrase inhibitors (INIs) (raltegravir, elvitegravir, dolutegravir), representing a new dimension in the anti-HIV armamentarium; (viii), a new class of helicase primase inhibitors (HPIs) that may exceed acyclovir and the other anti-herpes compounds in both potency and safety; (ix) CMX-001, as the latest of Dr. Antonín Holý's legacy for its activity against poxviruses and CMV infections, and (x) noroviruses for which the ideal antiviral compounds are still awaited for.

  1. Longitudinal liver stiffness assessment in patients with chronic hepatitis C undergoing antiviral therapy.

    Directory of Open Access Journals (Sweden)

    Stella M Martinez

    Full Text Available BACKGROUND/AIMS: Liver stiffness (LS measurement by means of transient elastography (TE is accurate to predict fibrosis stage. The effect of antiviral treatment and virologic response on LS was assessed and compared with untreated patients with chronic hepatitis C (CHC. METHODS: TE was performed at baseline, and at weeks 24, 48, and 72 in 515 patients with CHC. RESULTS: 323 treated (62.7% and 192 untreated patients (37.3% were assessed. LS experienced a significant decline in treated patients and remained stable in untreated patients at the end of study (P<0.0001. The decline was significant for patients with baseline LS ≥ 7.1 kPa (P<0.0001 and P 0.03, for LS ≥ 9.5 and ≥ 7.1 kPa vs lower values, respectively. Sustained virological responders and relapsers had a significant LS improvement whereas a trend was observed in nonresponders (mean percent change -16%, -10% and -2%, for SVR, RR and NR, respectively, P 0.03 for SVR vs NR. In multivariate analysis, high baseline LS (P<0.0001 and ALT levels, antiviral therapy and non-1 genotype were independent predictors of LS improvement. CONCLUSIONS: LS decreases during and after antiviral treatment in patients with CHC. The decrease is significant in sustained responders and relapsers (particularly in those with high baseline LS and suggests an improvement in liver damage.

  2. Longitudinal Liver Stiffness Assessment in Patients with Chronic Hepatitis C Undergoing Antiviral Therapy

    Science.gov (United States)

    Martinez, Stella M.; Foucher, Juliette; Combis, Jean-Marc; Métivier, Sophie; Brunetto, Maurizia; Capron, Dominique; Bourlière, Marc; Bronowicki, Jean-Pierre; Dao, Thong; Maynard-Muet, Marianne; Lucidarme, Damien; Merrouche, Wassil; Forns, Xavier; de Lédinghen, Victor

    2012-01-01

    Background/Aims Liver stiffness (LS) measurement by means of transient elastography (TE) is accurate to predict fibrosis stage. The effect of antiviral treatment and virologic response on LS was assessed and compared with untreated patients with chronic hepatitis C (CHC). Methods TE was performed at baseline, and at weeks 24, 48, and 72 in 515 patients with CHC. Results 323 treated (62.7%) and 192 untreated patients (37.3%) were assessed. LS experienced a significant decline in treated patients and remained stable in untreated patients at the end of study (P<0.0001). The decline was significant for patients with baseline LS ≥ 7.1 kPa (P<0.0001 and P 0.03, for LS ≥9.5 and ≥7.1 kPa vs lower values, respectively). Sustained virological responders and relapsers had a significant LS improvement whereas a trend was observed in nonresponders (mean percent change −16%, −10% and −2%, for SVR, RR and NR, respectively, P 0.03 for SVR vs NR). In multivariate analysis, high baseline LS (P<0.0001) and ALT levels, antiviral therapy and non-1 genotype were independent predictors of LS improvement. Conclusions LS decreases during and after antiviral treatment in patients with CHC. The decrease is significant in sustained responders and relapsers (particularly in those with high baseline LS) and suggests an improvement in liver damage. PMID:23082200

  3. Cutaneous manifestations of hepatitis C in the era of new antiviral agents

    Institute of Scientific and Technical Information of China (English)

    Simone; Garcovich; Matteo; Garcovich; Rodolfo; Capizzi; Antonio; Gasbarrini; Maria; Assunta; Zocco

    2015-01-01

    The association of chronic hepatitis C virus(HCV) infection with a wide spectrum of cutaneous manifestations has been widely reported in the literature, with varying strength of epidemiological association. Skin diseases which are certainly related with chronic HCV infection due to a strong epidemiological and pathogenetic association are mixed cryoglobulinemia, lichen planus and porphyria cutanea tarda. Chronic pruritus and necrolytic acral erythema are conditions that may share a possible association with HCV infection, while several immune-mediated inflammatory skin conditions, such as psoriasis, chronic urticaria and vitiligo, have been only anecdotally reported in the setting of chronic HCV infection. Traditional interferonbased treatment regimens for HCV infection are associated with substantial toxicity and a high-risk of immune-related adverse events, while the advent of new direct-acting antivirals with sustained virological response and improved tolerability will open the door for all-oral, interferon-free regimens. In the new era of these direct acting antivirals there will be hopefully a renewed interest in extra-hepatic manifestations of HCV infection. The aim of the present paper is to review the main cutaneous HCV-related disorders- mixed cryoglobulinemia, lichen planus, porphyria cutanea tarda and chronic pruritus- and to discuss the potential impact of new antiviral treatments on the course of these extrahepatic manifestations of chronic HCV infection.

  4. NaVirCept - Nucleic Acid-Based Anti-Viral Project

    International Nuclear Information System (INIS)

    Vaccines are generally considered to be the most effective countermeasures to bacterial and viral diseases, however, licensed vaccines against many disease agents are either not available or their efficacies have not been demonstrated. Vaccines are generally agent specific in terms of treatment spectrum and are subject to defeat through natural mutation or through directed efforts. With respect to viral therapeutics, one of the major limitations associated with antiviral drugs is acquired drug resistance caused by antigenic shift or drift. A number of next-generation prophylactic and/or therapeutic measures are on the horizon. Of these, nucleic acid-based drugs are showing great antiviral potential. These drugs elicit long-lasting, broad spectrum protective immune responses, especially to respiratory viral pathogens. The Nucleic Acid-Based Antiviral (NaVirCept) project provides the opportunity to demonstrate the effectiveness of novel medical countermeasures against military-significant endemic and other viral threat agents. This project expands existing DRDC drug delivery capability development, in the form of proprietary liposome intellectual property, by coupling it with leading-edge nucleic acid-based technology to deliver effective medical countermeasures that will protect deployed personnel and the warfighter against a spectrum of viral disease agents. The technology pathway will offer a means to combat emerging viral diseases or modified threat agents such as the bird flu or reconstructed Spanish flu without going down the laborious, time-consuming and expensive paths to develop countermeasures for each new and/or emerging viral disease organism.(author)

  5. Resistance to antivirals in human cytomegalovirus: mechanisms and clinical significance.

    Science.gov (United States)

    Pérez, J L

    1997-09-01

    Long term therapies needed for managing human cytomegalovirus (HCMV) infections in immunosupressed patients provided the background for the emergence of the resistance to antivirals active against HCMV. In addition, laboratory selected mutants have also been readily achieved. Both clinical and laboratory resistant strains share the same determinants of resistance. Ganciclovir resistance may be due to a few mutations in the HCMV UL97 gene and/or viral DNA pol gene, the former being responsible for about 70% of clinical resistant isolates. Among them, V464, V594, S595 and F595 are the most frequent mutations. Because of their less extensive clinical use, much less is known about resistance to foscarnet and cidofovir (formerly, HPMPC) but in both cases, it has been associated to mutations in the DNA pol. Ganciclovir resistant strains showing DNA pol mutations are cross-resistant to cidofovir and their corresponding IC50 are normally higher than those from strains harboring only mutations at the UL97 gene. To date, foscarnet resistance seems to be independent of both ganciclovir and cidofovir resistance.

  6. Regulation of the Host Antiviral State by Intercellular Communications

    Directory of Open Access Journals (Sweden)

    Sonia Assil

    2015-08-01

    Full Text Available Viruses usually induce a profound remodeling of host cells, including the usurpation of host machinery to support their replication and production of virions to invade new cells. Nonetheless, recognition of viruses by the host often triggers innate immune signaling, preventing viral spread and modulating the function of immune cells. It conventionally occurs through production of antiviral factors and cytokines by infected cells. Virtually all viruses have evolved mechanisms to blunt such responses. Importantly, it is becoming increasingly recognized that infected cells also transmit signals to regulate innate immunity in uninfected neighboring cells. These alternative pathways are notably mediated by vesicular secretion of various virus- and host-derived products (miRNAs, RNAs, and proteins and non-infectious viral particles. In this review, we focus on these newly-described modes of cell-to-cell communications and their impact on neighboring cell functions. The reception of these signals can have anti- and pro-viral impacts, as well as more complex effects in the host such as oncogenesis and inflammation. Therefore, these “broadcasting” functions, which might be tuned by an arms race involving selective evolution driven by either the host or the virus, constitute novel and original regulations of viral infection, either highly localized or systemic.

  7. Chemical diversity and antiviral potential in the pantropical Diospyros genus.

    Science.gov (United States)

    Peyrat, Laure-Anne; Eparvier, Véronique; Eydoux, Cécilia; Guillemot, Jean-Claude; Stien, Didier; Litaudon, Marc

    2016-07-01

    A screening using a dengue replicon virus-cell-based assay was performed on 3563 ethyl acetate (EtOAc) extracts from different parts of 1500 plants. The screening led to the selection of species from the genus Diospyros (Ebenaceae), among which 25 species distributed in tropical areas showed significant inhibitory activity on dengue virus replication. A metabolic analysis was conducted from the UPLC-HRMS profiles of 33 biologically active and inactive plant extracts, and their metabolic proximity is presented in the form of a dendrogram. The results of the study showed that chemical similarity is not related to plant species or organ. Overall, metabolomic profiling allowed us to define large groups of extracts, comprising both active and inactive ones. Closely related profiles from active extracts might indicate that the common major components of these extracts were responsible for the antiviral activity, while the comparison of chemically similar active and inactive extracts, will permit to find compounds of interest. Eventually, the phytochemical investigation of Diospyros glans bark EtOAc extract afforded usnic acid and 7 known ursane- and lupane-type triterpenoids, among which 5 were found significantly active against dengue virus replication. The inhibitory potency of these compounds was also evaluated on a DENV-NS5 RNA-dependant RNA polymerase assay. PMID:27126897

  8. Antiviral therapy of hepatitis C as curative treatment of indolent B-cell lymphoma

    Science.gov (United States)

    Merli, Michele; Carli, Giuseppe; Arcaini, Luca; Visco, Carlo

    2016-01-01

    The association of hepatitis C virus (HCV) and B-cell non-Hodgkin lymphomas (NHL) has been highlighted by several epidemiological and biological insights; however the most convincing evidence is represented by interventional studies demonstrating the capability of antiviral treatment (AT) with interferon (IFN) with or without ribavirin to induce the regression of indolent lymphomas, especially of marginal-zone origin. In the largest published retrospective study (100 patients) the overall response rate (ORR) after first-line IFN-based AT was 77% (44% complete responses) and responses were sustainable (median duration of response 33 mo). These results were confirmed by a recent meta-analysis on 254 patients, demonstrating an ORR of 73%. Moreover this analysis confirmed the highly significant correlation between the achievement of viral eradication sustained virological response (SVR) and hematological responses. Two large prospective studies demonstrated that AT is associated with improved survival and argue in favor of current guidelines’ recommendation of AT as preferential first-line option in asymptomatic patients with HCV-associated indolent NHL. The recently approved direct-acting antiviral agents (DAAs) revolutionized the treatment of HCV infection, leading to SVR approaching 100% in all genotypes. Very preliminary data of IFN-free DAAs therapy in indolent HCV-positive NHL seem to confirm their activity in inducing lymphoma regression.

  9. the denver tube Combined with antiviral drugs In the treatment of HBV-related Cirrhosis with Refractory ascites:a Report of three Cases

    Institute of Scientific and Technical Information of China (English)

    Xiao-jin Wang; Li-qin Shi; Qing-chun Fu; Liu-da Ni; Feng Zhou; Jin-wei Chen; Cheng-wei Chen

    2014-01-01

    Treatment of nucleos(t)ide antiviral drugs for decompensated HBV-related cirrhosis can signiifcantly improve the prognosis. But those patients with refractory ascites possibly deteriorate due to the complications of ascites before any beneift from anti-viral drugs could be observed. Therefore, it is important to ifnd a way to help the patients with HBV-related cirrhosis and refractory ascites to receive the full beneifts from antiviral therapy. Peritoneovenous shunt (PVS) using Denver tube enables ascites to continuously bypass into systemic circulation, thereby reducing ascites and albumin input and improving quality of life. We report herein 3 cases of decompensated HBV-related cirrhosis with refractory ascites, PVS using Denver tube was combined with lamivudine for antiviral treatment before and after. Then, ascites was alleviated significantly or disapeared and viral responsed well. All patients achieved a satisfactory long-term survival from 6.7 to 14.7 years. It was suggested that the Denver shunt could be used as an adjuvant method to antiviral drugs for decompensated HBV-related cirrhosis with refractory ascites to help the patients reap the full beneifts and maximize efifcacy of antiviral treatment.

  10. Induction and suppression of innate antiviral responses by picornaviruses

    NARCIS (Netherlands)

    Feng, Qian; Langereis, Martijn A; van Kuppeveld, Frank J M

    2014-01-01

    The family Picornaviridae comprises of small, non-enveloped, positive-strand RNA viruses and contains many human and animal pathogens including enteroviruses (e.g. poliovirus, coxsackievirus, enterovirus 71 and rhinovirus), cardioviruses (e.g. encephalomyocarditis virus), hepatitis A virus and foot-

  11. Public health management of antiviral drugs during the 2009 H1N1 influenza pandemic: a survey of local health departments in California

    Directory of Open Access Journals (Sweden)

    Hunter Jennifer C

    2012-01-01

    Full Text Available Abstract Background The large-scale deployment of antiviral drugs from the Strategic National Stockpile during the 2009 H1N1 influenza response provides a unique opportunity to study local public health implementation of the medical countermeasure dispensing capability in a prolonged event of national significance. This study aims to describe the range of methods used by local health departments (LHDs in California to manage antiviral activities and to gain a better understanding of the related challenges experienced by health departments and their community partners. Methods This research employed a mixed-methods approach. First, a multi-disciplinary focus group of pandemic influenza planners from key stakeholder groups in California was convened in order to generate ideas and identify critical themes related to the local implementation of antiviral activities during the H1N1 influenza response. These qualitative data informed the development of a web-based survey, which was distributed to all 61 LHDs in California for the purpose of assessing the experiences of a representative sample of local health agencies in a large region. Results Forty-four LHDs participated in this study, representing 72% of the local public health agencies in California. While most communities dispensed a modest number of publicly purchased antivirals, LHDs nevertheless drew on their previous work and engaged in a number of antiviral activities, including: acquiring, allocating, distributing, dispensing, tracking, developing guidance, and communicating to the public and clinical community. LHDs also identified specific antiviral challenges presented by the H1N1 pandemic, including: reconciling multiple sources and versions of antiviral guidance, determining appropriate uses and recipients of publicly purchased antivirals, and staffing shortages. Conclusions The 2009 H1N1 influenza pandemic presented an unusual opportunity to learn about the role of local public health

  12. Age-prioritized use of antivirals during an influenza pandemic

    Directory of Open Access Journals (Sweden)

    Ajelli Marco

    2009-07-01

    Full Text Available Abstract Background The WHO suggested that governments stockpile, as part of preparations for the next influenza pandemic, sufficient influenza antiviral drugs to treat approximately 25% of their populations. Our aim is two-fold: first, since in many countries the antiviral stockpile is well below this level, we search for suboptimal strategies based on treatment provided only to an age-dependent fraction of cases. Second, since in some countries the stockpile exceeds the suggested minimum level, we search for optimal strategies for post-exposure prophylactic treatment of close contacts of cases. Methods We used a stochastic, spatially structured individual-based model, considering explicit transmission in households, schools and workplaces, to simulate the spatiotemporal spread of an influenza pandemic in Italy and to evaluate the efficacy of interventions based on age-prioritized use of antivirals. Results Our results show that the antiviral stockpile required for treatment of cases ranges from 10% to 35% of the population for R0 in 1.4 – 3. No suboptimal strategies, based on treatment provided to an age-dependent fraction of cases, were found able to remarkably reduce both clinical attack rate and antiviral drugs needs, though they can contribute to largely reduce the excess mortality. Treatment of all cases coupled with prophylaxis provided to younger individuals is the only intervention resulting in a significant reduction of the clinical attack rate and requiring a relatively small stockpile of antivirals. Conclusion Our results strongly suggest that governments stockpile sufficient influenza antiviral drugs to treat approximately 25% of their populations, under the assumption that R0 is not much larger than 2. In countries where the number of antiviral stockpiled exceeds the suggested minimum level, providing prophylaxis to younger individuals is an option that could be taken into account in preparedness plans. In countries where the

  13. ANTI-VIRAL ACTIVITY OF GLYCIRRHETINIC AND GLYCIRRHIZIC ACIDS

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    V. V. Zarubaev

    2016-01-01

    Full Text Available Influenza is a highly contagious human disease. In the course of use of antiviral drugs drug-resistant strains of the virus are formed, resulting in reduced efficiency of the chemotherapy. The review describes the biological activity of glycirrhetinic (GLA and glycirrhizic (GA acids in terms of their use as a therapeutic agent for viral infections. So, these compounds are against a broad spectrum of viruses, including herpes, corona-, alphaand flaviviruses, human immunodeficiency virus, vaccinia virus, poliovirus type I, vesicular stomatitis virus and influenza A virus. These data indicate that anti-viral effect of these compounds is due to several types of activity — direct antiviral effects, effects on cellular proand anti-viral and immunomodulating pathways, in particular by activation of innate immunity system. GA interferes with early steps of the viral reproductive cycle such as virus binding to its receptor, the absorption of the virus by endocytosis or virus decapsidation in the cytoplasm. This is due to the effect of GA-induced reduction of membrane fluidity. Thus, one mechanism for the antiviral activity of GA is that GA molecule increases the rigidity of cellular and viral membranes after incorporation in there. This results in increasing of energy threshold required for the formation of negative curvature at the fusion zones, as well as difficult lateral migration of the virus-receptor complexes. In addition, glycyrrhizin prevents interaction of viral nucleoprotein with cellular protein HMGB1, which is necessary for the viral life cycle. Glycyrrhizin also inhibits the induction of oxidative stress during influenza infection, exhibiting antioxidant properties, which leads to a reduction of virus-induced production of cytokines/chemokines, without affecting the replication of the virus. A wide spectrum of biological activity and effect on various aspects of the viral pathogenesis substantiate the effect of GA and GLA as a component

  14. Introduction to symposium: Arthropods and wildlife conservation: synergy in complex biological systems

    Science.gov (United States)

    The symposium will discuss the effects of arthropods and other stressors on wildlife conservation programs. Speakers with affiliations in wildlife biology, parasitology and entomology will be included in the program. Research of national and international interest will be presented....

  15. Manipulation of arthropod sex determination by endosymbionts : Diversity and molecular mechanisms

    NARCIS (Netherlands)

    Ma, W. -J.; Vavre, F.; Beukeboom, L. W.

    2014-01-01

    Arthropods exhibit a large variety of sex determination systems both at the chromosomal and molecular level. Male heterogamety, female heterogamety, and haplodiploidy occur frequently, but partially different genes are involved. Endosymbionts, such as Wolbachia, Cardinium, Rickettsia, and Spiroplasm

  16. Arthropod trace fossils from the Zhujiaqing Formation (Meishucunian, Yunnan) and their palaeobiological implications

    Institute of Scientific and Technical Information of China (English)

    Bernd WEBER1; ZHU Maoyan

    2003-01-01

    Along with several non-arthropod ichnotaxa and rather non-specific scratchmarks, the Upper Phosphate of the Zhujiaqing Formation (Early Meishucunian Stage) in Eastern Yunnan yielded well-preserved resting and digging traces of the Rusophycus-type interpreted as resting traces of unknown large arthropods (ca. 3~6 cm in length). The discernible morphological details of these trace fossils enable a rough estimation of the body plan characteristics of the trace originators placing the latter doubtless into the early arthropods, if not euarthropods. The spectrum of the Meishucunian ichnoassemblage, especially the different types of arthropod repichnia point to the existence of a complex benthic ecosystem consisting of animals with different behavioural patterns and life styles already during the earliest Cambrian (Nemakit-Daldyn), and demands the assumption of a longer evolutionary past history of the benthic life on earth before the so-called "Cambrian Explosion" of the metazoans.

  17. Exceptional preservation of eye structure in arthropod visual predators from the Middle Jurassic.

    Science.gov (United States)

    Vannier, Jean; Schoenemann, Brigitte; Gillot, Thomas; Charbonnier, Sylvain; Clarkson, Euan

    2016-01-01

    Vision has revolutionized the way animals explore their environment and interact with each other and rapidly became a major driving force in animal evolution. However, direct evidence of how ancient animals could perceive their environment is extremely difficult to obtain because internal eye structures are almost never fossilized. Here, we reconstruct with unprecedented resolution the three-dimensional structure of the huge compound eye of a 160-million-year-old thylacocephalan arthropod from the La Voulte exceptional fossil biota in SE France. This arthropod had about 18,000 lenses on each eye, which is a record among extinct and extant arthropods and is surpassed only by modern dragonflies. Combined information about its eyes, internal organs and gut contents obtained by X-ray microtomography lead to the conclusion that this thylacocephalan arthropod was a visual hunter probably adapted to illuminated environments, thus contradicting the hypothesis that La Voulte was a deep-water environment. PMID:26785293

  18. The tortoise or the hare? Impacts of within-host dynamics on transmission success of arthropod-borne viruses.

    Science.gov (United States)

    Althouse, Benjamin M; Hanley, Kathryn A

    2015-08-19

    Arthropod-borne viruses (arboviruses) are maintained in a cycle of alternating transmission between vertebrate hosts and arthropod vectors. Arboviruses possess RNA genomes capable of rapid diversification and adaptation, and the between-host trade-offs inherent to host alternation impose well-documented constraints on arbovirus evolution. Here, we investigate the less well-studied within-host trade-offs that shape arbovirus replication dynamics and transmission. Arboviruses generally establish lifelong infection in vectors but transient infection of variable magnitude (i.e. peak virus concentration) and duration in vertebrate hosts. In the majority of experimental infections of vertebrate hosts, both the magnitude and duration of arbovirus replication depended upon the dose of virus administered, with increasing dose resulting in greater magnitude but shorter duration of viraemia. This pattern suggests that the vertebrate immune response imposes a trade-off between the height and breadth of the virus replication curve. To investigate the impact of this trade-off on transmission, we used a simple modelling approach to contrast the effect of 'tortoise' (low magnitude, long duration viraemia) and 'hare' (high magnitude, short duration viraemia) arbovirus replication strategies on transmission. This model revealed that, counter to previous theory, arboviruses that adopt a tortoise strategy have higher rates of persistence in both host and vector populations.

  19. The cultivation of Bt corn producing Cry1Ac toxins does not adversely affect non-target arthropods.

    Science.gov (United States)

    Guo, Yanyan; Feng, Yanjie; Ge, Yang; Tetreau, Guillaume; Chen, Xiaowen; Dong, Xuehui; Shi, Wangpeng

    2014-01-01

    Transgenic corn producing Cry1Ac toxins from Bacillus thuringiensis (Bt) provides effective control of Asian corn borer, Ostrinia furnacalis (Guenée), and thus reduces insecticide applications. However, whether Bt corn exerts undesirable effects on non-target arthropods (NTAs) is still controversial. We conducted a 2-yr study in Shangzhuang Agricultural Experiment Station to assess the potential impact of Bt corn on field population density, biodiversity, community composition and structure of NTAs. On each sampling date, the total abundance, Shannon's diversity index, Pielou's evenness index and Simpson's diversity index were not significantly affected by Bt corn as compared to non-Bt corn. The "sampling dates" had a significant effect on these indices, but no clear tendencies related to "Bt corn" or "sampling dates X corn variety" interaction were recorded. Principal response curve analysis of variance indicated that Bt corn did not alter the distribution of NTAs communities. Bray-Curtis dissimilarity and distance analysis showed that Cry1Ac toxin exposure did not increase community dissimilarities between Bt and non-Bt corn plots and that the evolution of non-target arthropod community was similar on the two corn varieties. The cultivation of Bt corn failed to show any detrimental evidence on the density of non-target herbivores, predators and parasitoids. The composition of herbivores, predators and parasitoids was identical in Bt and non-Bt corn plots. Taken together, results from the present work support that Bt corn producing Cry1Ac toxins does not adversely affect NTAs.

  20. A systematic review of arthropod community diversity in association with invasive plants

    OpenAIRE

    Spafford, Ryan D; Lortie, Christopher J.; Butterfield, Bradley J.

    2013-01-01

    Invasive plants represent a significant financial burden for land managers and also have the potential to severely degrade ecosystems. Arthropods interact strongly with plants, relying on them for food, shelter, and as nurseries for their young. For these reasons, the impacts of plant invasions are likely strongly reflected by arthropod community dynamics including diversity and abundances. A systematic review was conducted to ascertain the state of the literature with respect to plant invade...

  1. Arthropod diversity in pure oak forests of coppice origin in northern Thrace (Turkey

    Directory of Open Access Journals (Sweden)

    Keten A

    2015-10-01

    Full Text Available Oak (Quercus spp. forests are among the most important forest types in Turkey. In the past, oak forests were managed through coppice clear-cutting, but in recent decades they have mostly been converted to high forest. This study was aimed at explaining how arthropod diversity is affected during conversion from coppice to high oak forest and during the early stages of coppice succession. We tested the hypothesis that arthropod richness, abundance and diversity in coppice oak sites varied according to stand age and a number of other forest characteristics. Arthropod communities were sampled in 50 plots using four different methods: pitfall traps, sweep nets, sticky cards and cloth shaking. A total of 13 084 individuals were collected and classified into 193 Recognizable Taxonomic Units (RTUs, with the most RTUs and the greatest number of specimens captured by sweep netting. We identified 17 taxa within RTU’s with more than 1% of the captured arthropods, which constituted 75% of the total specimens. The number of RTUs varied significantly according to trap type. Arthropod richness and Shannon-Wiener biodiversity index (H′ increased with elevation and precipitation. In young (1-40 yrs-old and middle-aged (41-80 yrs stands, arthropod biodiversity was not significantly affected by stand type, but slightly increased with diameter at breast height and tree height. Forest characteristics, such as the litter layer, understory and crown diameter, weakly influenced arthropod richness and abundance. Cluster analysis revealed that stand types and trap types differed taxonomically. Principal component analysis showed that stand types were clearly separated by the stand parameters measured. Insect families (Formicidae, Thripidae, Lygaeidae, Dolichopodidae, Luaxanidae, Cicadellidae and Ichneumonidae could potentially be used as indicators of coppice oak conditions. As the coppice oak changes to mature forest, further studies are needed to better assess the

  2. Dynamics of the leaf-litter arthropod fauna following fire in a neotropical woodland savanna.

    Directory of Open Access Journals (Sweden)

    Heraldo L Vasconcelos

    Full Text Available Fire is an important agent of disturbance in tropical savannas, but relatively few studies have analyzed how soil-and-litter dwelling arthropods respond to fire disturbance despite the critical role these organisms play in nutrient cycling and other biogeochemical processes. Following the incursion of a fire into a woodland savanna ecological reserve in Central Brazil, we monitored the dynamics of litter-arthropod populations for nearly two years in one burned and one unburned area of the reserve. We also performed a reciprocal transplant experiment to determine the effects of fire and litter type on the dynamics of litter colonization by arthropods. Overall arthropod abundance, the abundance of individual taxa, the richness of taxonomic groups, and the species richness of individual taxa (Formiciade were lower in the burned site. However, both the ordinal-level composition of the litter arthropod fauna and the species-level composition of the litter ant fauna were not dramatically different in the burned and unburned sites. There is evidence that seasonality of rainfall interacts with fire, as differences in arthropod abundance and diversity were more pronounced in the dry than in the wet season. For many taxa the differences in abundance between burned and unburned sites were maintained even when controlling for litter availability and quality. In contrast, differences in abundance for Collembola, Formicidae, and Thysanoptera were only detected in the unmanipulated samples, which had a lower amount of litter in the burned than in the unburned site throughout most of our study period. Together these results suggest that arthropod density declines in fire-disturbed areas as a result of direct mortality, diminished resources (i.e., reduced litter cover and less favorable microclimate (i.e., increased litter desiccation due to reduction in tree cover. Although these effects were transitory, there is evidence that the increasingly prevalent fire

  3. Influence of Selective Insecticides and Cropping System on Arthropod Natural Enemies in Soybean

    OpenAIRE

    Whalen, Rebecca Anne

    2016-01-01

    Arthropod natural enemies play a key role in controlling potentially damaging pest populations in agroecosystems. An abundant and diverse natural enemy community is associated with higher yields in a variety of crops. Certain aspects of soybean production can make a field more or less amenable to a robust natural enemy community. For instance, commonly used broad-spectrum insecticides which are highly toxic to most arthropods can decrease natural enemy densities and allow for secondary pest o...

  4. Genetic Variation in Functional Traits Influences Arthropod Community Composition in Aspen (Populus tremula L.)

    OpenAIRE

    Robinson, Kathryn M; Pär K Ingvarsson; Jansson, Stefan; Albrectsen, Benedicte R.

    2012-01-01

    We conducted a study of natural variation in functional leaf traits and herbivory in 116 clones of European aspen, Populus tremula L., the Swedish Aspen (SwAsp) collection, originating from ten degrees of latitude across Sweden and grown in a common garden. In surveys of phytophagous arthropods over two years, we found the aspen canopy supports nearly 100 morphospecies. We identified significant broad-sense heritability of plant functional traits, basic plant defence chemistry, and arthropod ...

  5. Antiviral effect of ranpirnase against Ebola virus.

    Science.gov (United States)

    Hodge, Thomas; Draper, Ken; Brasel, Trevor; Freiberg, Alexander; Squiquera, Luis; Sidransky, David; Sulley, Jamie; Taxman, Debra J

    2016-08-01

    The recent epidemic of Ebola has intensified the need for the development of novel antiviral therapeutics that prolong and improve survival against deadly viral diseases. We sought to determine whether ranpirnase, an endoribonuclease from Rana pipiens with a demonstrated human safety profile in phase III oncology trials, can reduce titers of Ebola virus (EBOV) in infected cells, protect mice against mouse-adapted EBOV challenge, and reduce virus levels in infected mice. Our results demonstrate that 0.50 μg/ml ranpirnase is potently effective at reducing EBOV Zaire Kikwit infection in cultured Vero E6 cells (Selectivity Index 47.8-70.2). In a prophylactic study, a single intravenous dose of 0.1 mg/kg ranpirnase protected 70% of mice from progressive infection. Additionally, in a post-exposure prophylactic study, 100% of female mice survived infection after intraperitoneal administration of 0.1 mg/kg ranpirnase for ten days beginning 1 h post challenge. Most of the male counterparts were sacrificed due to weight loss by Study Day 8 or 9; however, the Clinical Activity/Behavior scores of these mice remained low and no significant microscopic pathologies could be detected in the kidneys, livers or spleens. Furthermore, live virus could not be detected in the sera of ranpirnase-treated mice by Study Day 8 or in the kidneys, livers or spleens by Study Day 12, and viral RNA levels declined exponentially by Study Day 12. Because ranpirnase is exceptionally stable and has a long track record of safe intravenous administration to humans, this drug provides a promising new candidate for clinical consideration in the treatment of Ebola virus disease alone or in combination with other therapeutics. PMID:27350309

  6. High throughput screening for small molecule enhancers of the interferon signaling pathway to drive next-generation antiviral drug discovery.

    Directory of Open Access Journals (Sweden)

    Dhara A Patel

    Full Text Available Most of current strategies for antiviral therapeutics target the virus specifically and directly, but an alternative approach to drug discovery might be to enhance the immune response to a broad range of viruses. Based on clinical observation in humans and successful genetic strategies in experimental models, we reasoned that an improved interferon (IFN signaling system might better protect against viral infection. Here we aimed to identify small molecular weight compounds that might mimic this beneficial effect and improve antiviral defense. Accordingly, we developed a cell-based high-throughput screening (HTS assay to identify small molecules that enhance the IFN signaling pathway components. The assay is based on a phenotypic screen for increased IFN-stimulated response element (ISRE activity in a fully automated and robust format (Z'>0.7. Application of this assay system to a library of 2240 compounds (including 2160 already approved or approvable drugs led to the identification of 64 compounds with significant ISRE activity. From these, we chose the anthracycline antibiotic, idarubicin, for further validation and mechanism based on activity in the sub-µM range. We found that idarubicin action to increase ISRE activity was manifest by other members of this drug class and was independent of cytotoxic or topoisomerase inhibitory effects as well as endogenous IFN signaling or production. We also observed that this compound conferred a consequent increase in IFN-stimulated gene (ISG expression and a significant antiviral effect using a similar dose-range in a cell-culture system inoculated with encephalomyocarditis virus (EMCV. The antiviral effect was also found at compound concentrations below the ones observed for cytotoxicity. Taken together, our results provide proof of concept for using activators of components of the IFN signaling pathway to improve IFN efficacy and antiviral immune defense as well as a validated HTS approach to identify

  7. Reduced interleukin-4 receptor α expression on CD8+ T cells correlates with higher quality anti-viral immunity.

    Directory of Open Access Journals (Sweden)

    Danushka K Wijesundara

    Full Text Available With the hope of understanding how interleukin (IL-4 and IL-13 modulated quality of anti-viral CD8(+ T cells, we evaluated the expression of receptors for these cytokines following a range of viral infections (e.g. pox viruses and influenza virus. Results clearly indicated that unlike other IL-4/IL-13 receptor subunits, IL-4 receptor α (IL-4Rα was significantly down-regulated on anti-viral CD8(+ T cells in a cognate antigen dependent manner. The infection of gene knockout mice and wild-type (WT mice with vaccinia virus (VV or VV expressing IL-4 confirmed that IL-4, IL-13 and signal transducer and activator of transcription 6 (STAT6 were required to increase IL-4Rα expression on CD8(+ T cells, but not interferon (IFN-γ. STAT6 dependent elevation of IL-4Rα expression on CD8(+ T cells was a feature of poor quality anti-viral CD8(+ T cell immunity as measured by the production of IFN-γ and tumor necrosis factor α (TNF-α in response to VV antigen stimulation in vitro. We propose that down-regulation of IL-4Rα, but not the other IL-4/IL-13 receptor subunits, is a mechanism by which CD8(+ T cells reduce responsiveness to IL-4 and IL-13. This can improve the quality of anti-viral CD8(+ T cell immunity. Our findings have important implications in understanding anti-viral CD8(+ T cell immunity and designing effective vaccines against chronic viral infections.

  8. Linking membrane physical properties and low temperature tolerance in arthropods.

    Science.gov (United States)

    Waagner, Dorthe; Bouvrais, Hélène; Ipsen, John H; Holmstrup, Martin

    2013-12-01

    Maintenance of membrane fluidity is of crucial importance in ectotherms experiencing thermal changes. This maintenance has in ectotherms most often been indicated using indirect measures of biochemical changes of phospholipid membranes, which is then assumed to modulate the physico-chemical properties of the membrane. Here, we measure bending rigidity characterizing the membrane flexibility of re-constituted membrane vesicles to provide a more direct link between membrane physical characteristics and low temperature tolerance. Bending rigidity of lipid bilayers was measured in vitro using Giant Unilamellar Vesicles formed from phospholipid extracts of the springtail, Folsomia candida. The bending rigidity of these membranes decreased when exposed to 0.4 vol% ethanol (0.23 mM/L). Springtails exposed to ethanol for 24h significantly increased their cold shock tolerance. Thus, by chemically inducing decreased membrane rigidity, we have shown a direct link between the physico-chemical properties of the membranes and the capacity to tolerate low temperature in a chill-susceptible arthropod. PMID:24080490

  9. Arthropod phylogeny based on eight molecular loci and morphology

    Science.gov (United States)

    Giribet, G.; Edgecombe, G. D.; Wheeler, W. C.

    2001-01-01

    The interrelationships of major clades within the Arthropoda remain one of the most contentious issues in systematics, which has traditionally been the domain of morphologists. A growing body of DNA sequences and other types of molecular data has revitalized study of arthropod phylogeny and has inspired new considerations of character evolution. Novel hypotheses such as a crustacean-hexapod affinity were based on analyses of single or few genes and limited taxon sampling, but have received recent support from mitochondrial gene order, and eye and brain ultrastructure and neurogenesis. Here we assess relationships within Arthropoda based on a synthesis of all well sampled molecular loci together with a comprehensive data set of morphological, developmental, ultrastructural and gene-order characters. The molecular data include sequences of three nuclear ribosomal genes, three nuclear protein-coding genes, and two mitochondrial genes (one protein coding, one ribosomal). We devised new optimization procedures and constructed a parallel computer cluster with 256 central processing units to analyse molecular data on a scale not previously possible. The optimal 'total evidence' cladogram supports the crustacean-hexapod clade, recognizes pycnogonids as sister to other euarthropods, and indicates monophyly of Myriapoda and Mandibulata.

  10. [Structure of parasitic arthropod communities in forest small mammals].

    Science.gov (United States)

    Balashov, Iu S

    2004-01-01

    Species composition and structure of ectoparasite arthropod communities were examined all year round six years in the bank vole Clethrionomys glareolus, Ural wood mouse Apodemus uralensis and the common shrew Sorex araneus in forests of the Ilmen'-Volkhov depression. In total, 4500 host samples have been examined and all ectoparasites have been collected. The species composition of ectoparasite community in small mammal species are as follows: the bank vole--29 insect, tick and mite species, the common shrew--23 species, the Ural wood mouse--16 species. In forest biotopes, many temporary ectoparasitic species occur on several host species living in the same habitats under a forest canopy and contacting each other. A parasitic supracommunity in the ecosystem examined has a pool of temporary ectoparasites, which is available for all the community of small mammals. A role of different rodent and shrew species are hosts of insects and ticks changes depending on a density of potential host populations and numerous other environment factors. PMID:15656091

  11. Arthropod-borne infections in travelled dogs in Europe

    Directory of Open Access Journals (Sweden)

    Hamel Dietmar

    2013-01-01

    Full Text Available Pet animal movement is ever increasing within the European Union and in that context canine vectorborne infections gained a considerable importance. Information on these infections in travelled dogs is nevertheless limited. A first prospective study on vector-borne infections was conducted in 106 dogs travelling from Germany to countries in South and South-East Europe. The dogs were screened prior to and consecutively up to three times after travel by haematological (Giemsa-stained buffy coat smears, Knott’s-Test, molecular biological (PCR as well as serological (IFAT, DiroChek®-ELISA methods for arthropod-borne infections. Seven animals were seropositive for antibodies against Babesia canis sspp., Leishmania spp. and/or Ehrlichia canis prior to travel to Italy, Spain, France, Croatia, Greece, or Hungary. In the consecutive screening after return there was no increase in the number of seropositive dogs. None was positive in direct methods. The mean duration of the stay was 17 days and 51% of the dogs were prophylactically treated with ectoparasiticidal formulations. Preliminary data from this study on canine vector-borne infections indicate a low risk for infection during a limited single stay in endemic countries.

  12. Plant and arthropod community sensitivity to rainfall manipulation but not nitrogen enrichment in a successional grassland ecosystem.

    Science.gov (United States)

    Lee, Mark A; Manning, Pete; Walker, Catherine S; Power, Sally A

    2014-12-01

    Grasslands provide many ecosystem services including carbon storage, biodiversity preservation and livestock forage production. These ecosystem services will change in the future in response to multiple global environmental changes, including climate change and increased nitrogen inputs. We conducted an experimental study over 3 years in a mesotrophic grassland ecosystem in southern England. We aimed to expose plots to rainfall manipulation that simulated IPCC 4th Assessment projections for 2100 (+15% winter rainfall and -30% summer rainfall) or ambient climate, achieving +15% winter rainfall and -39% summer rainfall in rainfall-manipulated plots. Nitrogen (40 kg ha(-1) year(-1)) was also added to half of the experimental plots in factorial combination. Plant species composition and above ground biomass were not affected by rainfall in the first 2 years and the plant community did not respond to nitrogen enrichment throughout the experiment. In the third year, above-ground plant biomass declined in rainfall-manipulated plots, driven by a decline in the abundances of grass species characteristic of moist soils. Declining plant biomass was also associated with changes to arthropod communities, with lower abundances of plant-feeding Auchenorrhyncha and carnivorous Araneae indicating multi-trophic responses to rainfall manipulation. Plant and arthropod community composition and plant biomass responses to rainfall manipulation were not modified by nitrogen enrichment, which was not expected, but may have resulted from prior nitrogen saturation and/or phosphorus limitation. Overall, our study demonstrates that climate change may in future influence plant productivity and induce multi-trophic responses in grasslands. PMID:25224801

  13. An Interferon Regulated MicroRNA Provides Broad Cell-Intrinsic Antiviral Immunity through Multihit Host-Directed Targeting of the Sterol Pathway.

    Directory of Open Access Journals (Sweden)

    Kevin A Robertson

    2016-03-01

    Full Text Available In invertebrates, small interfering RNAs are at the vanguard of cell-autonomous antiviral immunity. In contrast, antiviral mechanisms initiated by interferon (IFN signaling predominate in mammals. Whilst mammalian IFN-induced miRNA are known to inhibit specific viruses, it is not known whether host-directed microRNAs, downstream of IFN-signaling, have a role in mediating broad antiviral resistance. By performing an integrative, systematic, global analysis of RNA turnover utilizing 4-thiouridine labeling of newly transcribed RNA and pri/pre-miRNA in IFN-activated macrophages, we identify a new post-transcriptional viral defense mechanism mediated by miR-342-5p. On the basis of ChIP and site-directed promoter mutagenesis experiments, we find the synthesis of miR-342-5p is coupled to the antiviral IFN response via the IFN-induced transcription factor, IRF1. Strikingly, we find miR-342-5p targets mevalonate-sterol biosynthesis using a multihit mechanism suppressing the pathway at different functional levels: transcriptionally via SREBF2, post-transcriptionally via miR-33, and enzymatically via IDI1 and SC4MOL. Mass spectrometry-based lipidomics and enzymatic assays demonstrate the targeting mechanisms reduce intermediate sterol pathway metabolites and total cholesterol in macrophages. These results reveal a previously unrecognized mechanism by which IFN regulates the sterol pathway. The sterol pathway is known to be an integral part of the macrophage IFN antiviral response, and we show that miR-342-5p exerts broad antiviral effects against multiple, unrelated pathogenic viruses such Cytomegalovirus and Influenza A (H1N1. Metabolic rescue experiments confirm the specificity of these effects and demonstrate that unrelated viruses have differential mevalonate and sterol pathway requirements for their replication. This study, therefore, advances the general concept of broad antiviral defense through multihit targeting of a single host pathway.

  14. An Interferon Regulated MicroRNA Provides Broad Cell-Intrinsic Antiviral Immunity through Multihit Host-Directed Targeting of the Sterol Pathway.

    Science.gov (United States)

    Robertson, Kevin A; Hsieh, Wei Yuan; Forster, Thorsten; Blanc, Mathieu; Lu, Hongjin; Crick, Peter J; Yutuc, Eylan; Watterson, Steven; Martin, Kimberly; Griffiths, Samantha J; Enright, Anton J; Yamamoto, Mami; Pradeepa, Madapura M; Lennox, Kimberly A; Behlke, Mark A; Talbot, Simon; Haas, Jürgen; Dölken, Lars; Griffiths, William J; Wang, Yuqin; Angulo, Ana; Ghazal, Peter

    2016-03-01

    In invertebrates, small interfering RNAs are at the vanguard of cell-autonomous antiviral immunity. In contrast, antiviral mechanisms initiated by interferon (IFN) signaling predominate in mammals. Whilst mammalian IFN-induced miRNA are known to inhibit specific viruses, it is not known whether host-directed microRNAs, downstream of IFN-signaling, have a role in mediating broad antiviral resistance. By performing an integrative, systematic, global analysis of RNA turnover utilizing 4-thiouridine labeling of newly transcribed RNA and pri/pre-miRNA in IFN-activated macrophages, we identify a new post-transcriptional viral defense mechanism mediated by miR-342-5p. On the basis of ChIP and site-directed promoter mutagenesis experiments, we find the synthesis of miR-342-5p is coupled to the antiviral IFN response via the IFN-induced transcription factor, IRF1. Strikingly, we find miR-342-5p targets mevalonate-sterol biosynthesis using a multihit mechanism suppressing the pathway at different functional levels: transcriptionally via SREBF2, post-transcriptionally via miR-33, and enzymatically via IDI1 and SC4MOL. Mass spectrometry-based lipidomics and enzymatic assays demonstrate the targeting mechanisms reduce intermediate sterol pathway metabolites and total cholesterol in macrophages. These results reveal a previously unrecognized mechanism by which IFN regulates the sterol pathway. The sterol pathway is known to be an integral part of the macrophage IFN antiviral response, and we show that miR-342-5p exerts broad antiviral effects against multiple, unrelated pathogenic viruses such Cytomegalovirus and Influenza A (H1N1). Metabolic rescue experiments confirm the specificity of these effects and demonstrate that unrelated viruses have differential mevalonate and sterol pathway requirements for their replication. This study, therefore, advances the general concept of broad antiviral defense through multihit targeting of a single host pathway.

  15. Actinobacteria from Termite Mounds Show Antiviral Activity against Bovine Viral Diarrhea Virus, a Surrogate Model for Hepatitis C Virus

    Directory of Open Access Journals (Sweden)

    Marina Aiello Padilla

    2015-01-01

    Full Text Available Extracts from termite-associated bacteria were evaluated for in vitro antiviral activity against bovine viral diarrhea virus (BVDV. Two bacterial strains were identified as active, with percentages of inhibition (IP equal to 98%. Both strains were subjected to functional analysis via the addition of virus and extract at different time points in cell culture; the results showed that they were effective as posttreatments. Moreover, we performed MTT colorimetric assays to identify the CC50, IC50, and SI values of these strains, and strain CDPA27 was considered the most promising. In parallel, the isolates were identified as Streptomyces through 16S rRNA gene sequencing analysis. Specifically, CDPA27 was identified as S. chartreusis. The CDPA27 extract was fractionated on a C18-E SPE cartridge, and the fractions were reevaluated. A 100% methanol fraction was identified to contain the compound(s responsible for antiviral activity, which had an SI of 262.41. GC-MS analysis showed that this activity was likely associated with the compound(s that had a peak retention time of 5 min. Taken together, the results of the present study provide new information for antiviral research using natural sources, demonstrate the antiviral potential of Streptomyces chartreusis compounds isolated from termite mounds against BVDV, and lay the foundation for further studies on the treatment of HCV infection.

  16. Mechanisms of virus resistance and antiviral activity of snake venoms

    Directory of Open Access Journals (Sweden)

    JVR Rivero

    2011-01-01

    Full Text Available Viruses depend on cell metabolism for their own propagation. The need to foster an intimate relationship with the host has resulted in the development of various strategies designed to help virus escape from the defense mechanisms present in the host. Over millions of years, the unremitting battle between pathogens and their hosts has led to changes in evolution of the immune system. Snake venoms are biological resources that have antiviral activity, hence substances of significant pharmacological value. The biodiversity in Brazil with respect to snakes is one of the richest on the planet; nevertheless, studies on the antiviral activity of venom from Brazilian snakes are scarce. The antiviral properties of snake venom appear as new promising therapeutic alternative against the defense mechanisms developed by viruses. In the current study, scientific papers published in recent years on the antiviral activity of venom from various species of snakes were reviewed. The objective of this review is to discuss the mechanisms of resistance developed by viruses and the components of snake venoms that present antiviral activity, particularly, enzymes, amino acids, peptides and proteins.

  17. Screening for Antiviral Activities of Isolated Compounds from Essential Oils

    Directory of Open Access Journals (Sweden)

    Akram Astani

    2011-01-01

    Full Text Available Essential oil of star anise as well as phenylpropanoids and sesquiterpenes, for example, trans-anethole, eugenol, β-eudesmol, farnesol, β-caryophyllene and β-caryophyllene oxide, which are present in many essential oils, were examined for their antiviral activity against herpes simplex virus type 1 (HSV-1 in vitro. Antiviral activity was analyzed by plaque reduction assays and mode of antiviral action was determined by addition of the drugs to uninfected cells, to the virus prior to infection or to herpesvirus-infected cells. Star anise oil reduced viral infectivity by >99%, phenylpropanoids inhibited HSV infectivity by about 60–80% and sesquiterpenes suppressed herpes virus infection by 40–98%. Both, star anise essential oil and all isolated compounds exhibited anti-HSV-1 activity by direct inactivation of free virus particles in viral suspension assays. All tested drugs interacted in a dose-dependent manner with herpesvirus particles, thereby inactivating viral infectivity. Star anise oil, rich in trans-anethole, revealed a high selectivity index of 160 against HSV, whereas among the isolated compounds only β-caryophyllene displayed a high selectivity index of 140. The presence of β-caryophyllene in many essential oils might contribute strongly to their antiviral ability. These results indicate that phenylpropanoids and sesquiterpenes present in essential oils contribute to their antiviral activity against HSV.

  18. Antiviral Screening of Multiple Compounds against Ebola Virus

    Directory of Open Access Journals (Sweden)

    Stuart D. Dowall

    2016-10-01

    Full Text Available In light of the recent outbreak of Ebola virus (EBOV disease in West Africa, there have been renewed efforts to search for effective antiviral countermeasures. A range of compounds currently available with broad antimicrobial activity have been tested for activity against EBOV. Using live EBOV, eighteen candidate compounds were screened for antiviral activity in vitro. The compounds were selected on a rational basis because their mechanisms of action suggested that they had the potential to disrupt EBOV entry, replication or exit from cells or because they had displayed some antiviral activity against EBOV in previous tests. Nine compounds caused no reduction in viral replication despite cells remaining healthy, so they were excluded from further analysis (zidovudine; didanosine; stavudine; abacavir sulphate; entecavir; JB1a; Aimspro; celgosivir; and castanospermine. A second screen of the remaining compounds and the feasibility of appropriateness for in vivo testing removed six further compounds (ouabain; omeprazole; esomeprazole; Gleevec; D-LANA-14; and Tasigna. The three most promising compounds (17-DMAG; BGB324; and NCK-8 were further screened for in vivo activity in the guinea pig model of EBOV disease. Two of the compounds, BGB324 and NCK-8, showed some effect against lethal infection in vivo at the concentrations tested, which warrants further investigation. Further, these data add to the body of knowledge on the antiviral activities of multiple compounds against EBOV and indicate that the scientific community should invest more effort into the development of novel and specific antiviral compounds to treat Ebola virus disease.

  19. Virus-Heat Shock Protein Interaction and a Novel Axis for Innate Antiviral Immunity

    Directory of Open Access Journals (Sweden)

    Michael Oglesbee

    2012-09-01

    Full Text Available Virus infections induce heat shock proteins that in turn enhance virus gene expression, a phenomenon that is particularly well characterized for the major inducible 70 kDa heat shock protein (hsp70. However, hsp70 is also readily induced by fever, a phylogenetically conserved response to microbial infections, and when released from cells, hsp70 can stimulate innate immune responses through toll like receptors 2 and 4 (TLR2 and 4. This review examines how the virus-hsp70 relationship can lead to host protective innate antiviral immunity, and the importance of hsp70 dependent stimulation of virus gene expression in this host response. Beginning with the well-characterized measles virus-hsp70 relationship and the mouse model of neuronal infection in brain, we examine data indicating that the innate immune response is not driven by intracellular sensors of pathogen associated molecular patterns, but rather by extracellular ligands signaling through TLR2 and 4. Specifically, we address the relationship between virus gene expression, extracellular release of hsp70 (as a damage associated molecular pattern, and hsp70-mediated induction of antigen presentation and type 1 interferons in uninfected macrophages as a novel axis of antiviral immunity. New data are discussed that examines the more broad relevance of this protective mechanism using vesicular stomatitis virus, and a review of the literature is presented that supports the probable relevance to both RNA and DNA viruses and for infections both within and outside of the central nervous system.

  20. Innate antiviral immune signaling, viral evasion and modulation by HIV-1.

    Science.gov (United States)

    Rustagi, Arjun; Gale, Michael

    2014-03-20

    The intracellular innate antiviral response in human cells is an essential component of immunity against virus infection. As obligate intracellular parasites, all viruses must evade the actions of the host cell's innate immune response in order to replicate and persist. Innate immunity is induced when pathogen recognition receptors of the host cell sense viral products including nucleic acid as "non-self". This process induces downstream signaling through adaptor proteins to activate latent transcription factors that drive the expression of genes encoding antiviral and immune modulatory effector proteins that restrict virus replication and regulate adaptive immunity. The interferon regulatory factors (IRFs) are transcription factors that play major roles in innate immunity. In particular, IRF3 is activated in response to infection by a range of viruses including RNA viruses, DNA viruses and retroviruses. Among these viruses, human immunodeficiency virus type 1 (HIV-1) remains a major global health problem mediating chronic infection in millions of people wherein recent studies show that viral persistence is linked with the ability of the virus to dysregulate and evade the innate immune response. In this review, we discuss viral pathogen sensing, innate immune signaling pathways and effectors that respond to viral infection, the role of IRF3 in these processes and how it is regulated by pathogenic viruses. We present a contemporary overview of the interplay between HIV-1 and innate immunity, with a focus on understanding how innate immune control impacts infection outcome and disease.

  1. New antiviral targets for innovative treatment concepts for hepatitis B virus and hepatitis delta virus.

    Science.gov (United States)

    Durantel, David; Zoulim, Fabien

    2016-04-01

    Current therapies of chronic hepatitis B (CHB) remain limited to pegylated-interferon-alpha (PegIFN-α) or any of the five approved nucleos(t)ide analogues (NUC) treatments. While viral suppression can be achieved in the majority of patients with the high-barrier-to-resistance new-generation of NUC, i.e. entecavir and tenofovir, HBsAg loss is achieved by PegIFN-α and/or NUC in only 10% of patients, after a 5-year follow-up. Attempts to improve the response by administering two different NUC or a combination of NUC and PegIFN-α have not provided a dramatic increase in the rate of functional cure. Because of this and the need of long-term NUC administration, there is a renewed interest regarding the understanding of various steps of the HBV replication cycle, as well as specific virus-host cell interactions, in order to define new targets and develop new antiviral drugs. This includes a direct inhibition of viral replication with entry inhibitors, drugs targeting cccDNA, siRNA targeting viral transcripts, capsid assembly modulators, and approaches targeting the secretion of viral envelope proteins. Restoration of immune responses is a complementary approach. The restoration of innate immunity against HBV can be achieved, with TLR agonists or specific antiviral cytokine delivery. Restoration of adaptive immunity may be achieved with inhibitors of negative checkpoint regulators, therapeutic vaccines, or autologous transfer of engineered HBV-specific T cells. Novel targets and compounds will readily be evaluated using both relevant and novel in vitro and in vivo models of HBV infection. The addition of one or several new drugs to current therapies should offer the prospect of a markedly improved response to treatments and an increased rate of functional cure. This should lead to a reduced risk of antiviral drug resistance, and to a decreased incidence of cirrhosis and hepatocellular carcinoma (HCC).

  2. Biological control of phytophagous arthropods in the physic nut tree Jatropha curcas L. in Brazil

    Directory of Open Access Journals (Sweden)

    Flávio Lemes Fernandes

    2014-11-01

    Full Text Available Jatropha curcas has a high biofuel oil content, which could replace polluting fuels, and has great potential for large scale monoculture cultivation in the conventional system. We explored the occurrence, spatial distribution and the functional response of the main phytophagous species of this plant and their natural enemies to explore the potential for conservative biological control. We began sampling phytophagous species and predators when J. curcas plants were six months old. The most common species of phytophagous insects were nymphs and adults of Empoasca kraemeri, followed by Frankliniella schultzei and Myzus persicae. Among the predators, Ricoseius loxocheles, Iphiseioides zuluagai, Araneidae, larvae and adults of Psyllobora vigintimaculata and Anthicus sp. were the most frequently encountered. The most common parasitoids were the families Encyrtidae and Braconidae. The highest densities of E. kraemeri and F. schultzei on the edges of the J. curcas crop follow spatial patterns similar to those of their natural enemies I. zuluagai and Anthicus sp. These arthropods can be considered efficient predators of immature stages of E. kraemeri and F. schultzei on J. curcas.

  3. Surveillance of arthropod vector-borne infectious diseases using remote sensing techniques: a review.

    Directory of Open Access Journals (Sweden)

    Satya Kalluri

    2007-10-01

    Full Text Available Epidemiologists are adopting new remote sensing techniques to study a variety of vector-borne diseases. Associations between satellite-derived environmental variables such as temperature, humidity, and land cover type and vector density are used to identify and characterize vector habitats. The convergence of factors such as the availability of multi-temporal satellite data and georeferenced epidemiological data, collaboration between remote sensing scientists and biologists, and the availability of sophisticated, statistical geographic information system and image processing algorithms in a desktop environment creates a fertile research environment. The use of remote sensing techniques to map vector-borne diseases has evolved significantly over the past 25 years. In this paper, we review the status of remote sensing studies of arthropod vector-borne diseases due to mosquitoes, ticks, blackflies, tsetse flies, and sandflies, which are responsible for the majority of vector-borne diseases in the world. Examples of simple image classification techniques that associate land use and land cover types with vector habitats, as well as complex statistical models that link satellite-derived multi-temporal meteorological observations with vector biology and abundance, are discussed here. Future improvements in remote sensing applications in epidemiology are also discussed.

  4. Surveillance of arthropod vector-borne infectious diseases using remote sensing techniques: a review.

    Science.gov (United States)

    Kalluri, Satya; Gilruth, Peter; Rogers, David; Szczur, Martha

    2007-10-26

    Epidemiologists are adopting new remote sensing techniques to study a variety of vector-borne diseases. Associations between satellite-derived environmental variables such as temperature, humidity, and land cover type and vector density are used to identify and characterize vector habitats. The convergence of factors such as the availability of multi-temporal satellite data and georeferenced epidemiological data, collaboration between remote sensing scientists and biologists, and the availability of sophisticated, statistical geographic information system and image processing algorithms in a desktop environment creates a fertile research environment. The use of remote sensing techniques to map vector-borne diseases has evolved significantly over the past 25 years. In this paper, we review the status of remote sensing studies of arthropod vector-borne diseases due to mosquitoes, ticks, blackflies, tsetse flies, and sandflies, which are responsible for the majority of vector-borne diseases in the world. Examples of simple image classification techniques that associate land use and land cover types with vector habitats, as well as complex statistical models that link satellite-derived multi-temporal meteorological observations with vector biology and abundance, are discussed here. Future improvements in remote sensing applications in epidemiology are also discussed.

  5. Importance of mosquito “quasispecies” in selecting an epidemic arthropod-borne virus

    Science.gov (United States)

    Vazeille, Marie; Zouache, Karima; Vega-Rúa, Anubis; Thiberge, Jean-Michel; Caro, Valérie; Yébakima, André; Mousson, Laurence; Piorkowski, Géraldine; Dauga, Catherine; Vaney, Marie-Christine; Manni, Mosè; Gasperi, Giuliano; de Lamballerie, Xavier; Failloux, Anna-Bella

    2016-01-01

    Most arthropod-borne viruses (arboviruses), perpetuated by alternation between a vertebrate host and an insect vector, are likely to emerge through minor genetic changes enabling the virus to adapt to new hosts. In the past decade, chikungunya virus (CHIKV; Alphavirus, Togaviridae) has emerged on La Réunion Island following the selection of a unique substitution in the CHIKV E1 envelope glycoprotein (E1-A226V) of an East-Central-South African (ECSA) genotype conferring a higher transmission rate by the mosquito Aedes albopictus. Assumed to have occurred independently on at least four separate occasions, this evolutionary convergence was suspected to be responsible for CHIKV worldwide expansion. However, assumptions on CHIKV emergence were mainly based on viral genetic changes and the role of the mosquito population quasispecies remained unexplored. Here we show that the nature of the vector population is pivotal in selecting the epidemic CHIKV. We demonstrate using microsatellites mosquito genotyping that Ae. albopictus populations are genetically differentiated, contributing to explain their differential ability to select the E1-226V mutation. Aedes albopictus, newly introduced in Congo coinciding with the first CHIKV outbreak, was not able to select the substitution E1-A226V nor to preferentially transmit a CHIKV clone harboring the E1-226V as did Ae. albopictus from La Réunion. PMID:27383735

  6. Effects of timing of grazing on arthropod communities in semi-natural grasslands.

    Science.gov (United States)

    Lenoir, Lisette; Lennartsson, Tommy

    2010-01-01

    Arthropod communities were investigated in two Swedish semi-natural grasslands, each subject to two types of grazing regime: conventional grazing from May to September (continuous grazing) and traditional late management from mid-July (late grazing). Pitfall traps were used to investigate abundance of carabids, spiders, and ants over the grazing season. Ant abundance was also measured by mapping nest density during three successive years. Small spiders, carabids and ants (Myrmica spp.) were more abundant in continuous grazing than in late grazing while larger spiders, carabids, and ants (Formica spp.) were more abundant in late grazing. The overall abundance of carabids was higher in continuous grazing in the early summer but higher in late grazing in the late summer. The switch of preference from continuous to late grazing coincided with the time for larvae hibernating species replacing adult hibernating. We discuss possible explanations for the observed responses in terms of effects of grazing season on a number of habitat variables for example temperature, food resources, structure of vegetation, litter layer, competition, and disturbance. PMID:20569138

  7. Mineral cycling in soil and litter arthropod food chains. Progress report, November 1, 1980-October 31, 1981

    International Nuclear Information System (INIS)

    Progress and current status are reported for research projects concerned with mineral element and nutrient dynamics in soil arthropod food chains. Research is performed within the larger context of terrestrial decomposition, in which soil arthropods may act as regulators of nutrient dynamics during decomposition. Research is measuring rates of nutrient accumulation and excretion by using radioactive tracer analogs of nutrients. This year, emphasis has been placed on field work in which soil arthropod population size and nutrients inputs were varied experimentally. The presence of microarthropods in field microcosms increased the mineralization of N and P in each case, but rates were not correlated with arthropod densities. Experiments recently started are using both arthropod and microfloral inhibitors, in open systems on the forest floor, with the objective of quantifying arthropod enhancement of microbial immobilization of nutrients

  8. A New Arthropod, Guangweicaris Luo, Fu et Hu gen. nov.from the Early Cambrian Guanshan Fauna, Kunming, China

    Institute of Scientific and Technical Information of China (English)

    LUO Huilin; FU Xiaoping; HU Shixue; LI Yong; HOU Shuguang; YOU Ting; PANG Jiyuan; LIU Qi

    2007-01-01

    The Guanshan Fauna is a soft-bodied fauna dominated by arthropods (including trilobites,trilobitoides, Tuzoia, Isoxys, and bradorids) in association with priapulids, brachiopods,anomalocaridids, vetulicoliids, sponges, chancellorids, and echinoderms. This paper reports and describes a new arthropod from the yellowish green mudstone at the lower part of the Wulongqing Formation, Canglangpuan Stage, Lower Cambrian in Kunming, Yunnan, China. The stratigraphic and geographic distribution, classification, fossil preservation, life style of this new arthropod and comparisons with other fossil arthropods are also discussed in details. The discovery and research of the non-mineralized arthropod, Guangweicaris Luo, Fu et Hu gen. nov. from the Guanshan Fauna adds new members to the taxonomic list and provides new information to the evolution of early arthropods.Furthermore, this study would shed new light into the "Cambrian Explosion" and the evolution of early life.

  9. IN VIVO SCREENING OF CHEMICAL MODIFICATIONS OF siRNAs FOR EFFECT ON THE INNATE IMMUNE RESPONSE IN FISH

    DEFF Research Database (Denmark)

    Lorenzen, Niels; Schyth, Brian Dall; Bramsen, J. B.;

    the antiviral activities of these duplexes. We conclude that the fish in vivo model is a potent tool for gaining insight into the overall triggering of antiviral reactions by siRNAs in vertebrates. The perspective is to learn how to avoid triggering of non-specific antiviral responses and still allow uptake...

  10. CEACAM1 induces B-cell survival and is essential for protective antiviral antibody production

    OpenAIRE

    Khairnar, Vishal; Duhan, Vikas; Maney, Sathish Kumar; Honke, Nadine; Shaabani, Namir; Pandyra, Aleksandra A; Seifert, Marc; Pozdeev, Vitaly; Xu, Haifeng C.; Sharma, Piyush; Baldin, Fabian; Marquardsen, Florian; Merches, Katja; Lang, Elisabeth; Kirschning, Carsten

    2015-01-01

    B cells are essential for antiviral immune defence because they produce neutralizing antibodies, present antigen and maintain the lymphoid architecture. Here we show that intrinsic signalling of CEACAM1 is essential for generating efficient B-cell responses. Although CEACAM1 exerts limited influence on the proliferation of B cells, expression of CEACAM1 induces survival of proliferating B cells via the BTK/Syk/NF-κB-axis. The absence of this signalling cascade in naive Ceacam1 −/− mice limits...

  11. Considerations on Direct Antiviral Agent Therapy in Patients Having Chronic Hepatitis C from Constanta County

    Directory of Open Access Journals (Sweden)

    Stavar Angelica

    2014-10-01

    Full Text Available Introduction: Direct-acting antiviral agents (DAA have a direct action in chronic hepatitis C, their addition to the standard therapy with interferon alfa2 (IFN and ribavirin (RBV significantly improving the sustained virologic response (SVR in this disease. Objective: The study analyses the results of triple therapy inclduign DAA in terms of tolerability and efficiency. Material and method: We selected a lot of 24 patients who concluded the DAA administration period, being in the period of finalization of standard therapy at the time of the study. In all the patients clinical and paraclinical assesment was performed including laboratory tests, fibroscan, echography, etc.

  12. Phytochemistry, cytotoxicity and antiviral activity of Eleusine indica (sambau)

    Science.gov (United States)

    Iberahim, Rashidah; Yaacob, Wan Ahmad; Ibrahim, Nazlina

    2015-09-01

    Goose grass also known as Eleusine indica (EI) is a local medicinal plant that displays antioxidant, antimicrobial and anticancer activities. The present study is to determine the phytochemical constituents, cytotoxicity and antiviral activities for both crude extract and fraction obtained from the plant. The crude extract contained more secondary metabolites compared to the hexane fraction as gauged using standard phytochemical tests. Cytotoxicity screening against Vero cells using MTT assay showed that the CC50 values for crude extract and hexane fraction were 2.07 and 5.62 mg/ml respectively. The antiviral activity towards Herpes Simplex Virus type 1 (HSV-1) was determined using plaque reduction assay. The selective indices (SI = CC50 / EC50) for both methanol extract and hexane fraction were 12.2 and 6.2 respectively. These results demonstrate that the extract prepared from E. indica possesses phytochemical compound that was non cytotoxic to the cell with potential antiviral activity.

  13. The Antiviral Effect of Baicalin on Enterovirus 71 In Vitro

    Directory of Open Access Journals (Sweden)

    Xiang Li

    2015-08-01

    Full Text Available Baicalin is a flavonoid compound extracted from Scutellaria roots that has been reported to possess antibacterial, anti-inflammatory, and antiviral activities. However, the antiviral effect of baicalin on enterovirus 71 (EV71 is still unknown. In this study, we found that baicalin showed inhibitory activity on EV71 infection and was independent of direct virucidal or prophylactic effect and inhibitory viral absorption. The expressions of EV71/3D mRNA and polymerase were significantly blocked by baicalin treatment at early stages of EV71 infection. In addition, baicalin could decrease the expressions of FasL and caspase-3, as well as inhibit the apoptosis of EV71-infected human embryonal rhabdomyosarcoma (RD cells. Altogether, these results indicate that baicalin exhibits potent antiviral effect on EV71 infection, probably through inhibiting EV71/3D polymerase expression and Fas/FasL signaling pathways.

  14. The Diversity and Abundance of Small Arthropods in Onion, Allium cepa, Seed Crops, and their Potential Role in Pollination

    OpenAIRE

    Walker, M.K.; Howlett, B. G.; Wallace, A.R.; Mccallum, J. A.; Teulon, D.A.J.

    2011-01-01

    Onion, Allium cepa L. (Asparagales: Amaryllidaceae), crop fields grown for seed production require arthropod pollination for adequate seed yield. Although many arthropod species visit A. cepa flowers, for most there is little information on their role as pollinators. Small flower visiting arthropods (body width < 3 mm) in particular are rarely assessed. A survey of eight flowering commercial A. cepa seed fields in the North and South Islands of New Zealand using window traps revealed that sma...

  15. Large-scale experimental landscapes reveal distinctive effects of patch shape and connectivity on arthropod communities.

    Energy Technology Data Exchange (ETDEWEB)

    Orrock, John, L.; Curler, Gregory, R.; Danielson, Brent, J.; Coyle, David. R.

    2011-09-14

    The size, shape, and isolation of habitat patches can affect organism behavior and population dynamics, but little is known about the relative role of shape and connectivity in affecting ecological communities at large spatial scales. Using six sampling sessions from July 2001 until August 2002, we collected 33,685 arthropods throughout seven 12-ha experimental landscapes consisting of clear-cut patches surrounded by a matrix of mature pine forest. Patches were explicitly designed to manipulate connectivity (via habitat corridors) independently of area and edge effects. We found that patch shape, rather than connectivity, affected ground-dwelling arthropod richness and beta diversity (i.e. turnover of genera among patches). Arthropod communities contained fewer genera and exhibited less turnover in high-edge connected and high-edge unconnected patches relative to low-edge unconnected patches of similar area. Connectivity, rather than patch shape, affected the evenness of ground-dwelling arthropod communities; regardless of patch shape, high-edge connected patches had lower evenness than low- or high-edge unconnected patches. Among the most abundant arthropod orders, increased richness in low-edge unconnected patches was largely due to increased richness of Coleoptera, whereas Hymenoptera played an important role in the lower evenness in connected patches and patterns of turnover. These findings suggest that anthropogenic habitat alteration can have distinct effects on ground-dwelling arthropod communities that arise due to changes in shape and connectivity. Moreover, this work suggests that corridors, which are common conservation tools that change both patch shape and connectivity, can have multiple effects on arthropod communities via different mechanisms, and each effect may alter components of community structure.

  16. Phylogeny and life habits of Early Arthropods-Predation in the Early Cambrian Sea

    Institute of Scientific and Technical Information of China (English)

    Andreas MAAS; Dieter WALOSZEK; CHEN Junyuan; Andreas BRAUN; WANG Xiuqiang; HUANG Diying

    2004-01-01

    We investigated two new arthropods from the Maotianshan-Shale fauna of southern China in the course of our research on life strategies, particularly predation, in Early Cambrian marine macrofaunal biota. One form clearly belongs to the so-called "great-appendage" arthropods, animals that were, most likely, active predators catching prey with their first pair of large, specialized frontoventral appendages. Based on this, we hypothesize that the new species and many others, if not all, of the "great-appendage" arthropods were derivatives of the chelicerate stem lineage and not forms having branched off at different nodes along the evolutionary lineage of the Arthropoda. Rather, we consider the "great-appendage" arthropods as belonging to a monophyletic clade, which modified autapomorphically their first pair of appendages (antennae in general arthropod terminology) into raptorial organs for food capture. The second new form resembles another Maotianshan-Shale arthropod, Fuxianhuia protensa, in sharing a head made of only two separate segments, a small segment bearing oval eyes laterally, and another bearing a large tergite, which forms a wide shield freely overhanging the subsequent narrow trunk segments. This segment bears a single pair of rather short anteriorly directed uniramous appendages, considered as the "still" limb-shaped antennae. Particularly the evolutionary status of head and limbs of these two forms suggests that both are representatives of the early part of the stem lineage toward the crown-group of Arthropoda, the Euarthropoda. These forms appear rather unspecialized, but may have been but simple predators. This adds to our hypothesis that predation was a common, if not dominant feeding strategy in the Cambrian, at least for arthropods.

  17. Habitat and species identity, not diversity, predict the extent of refuse consumption by urban arthropods.

    Science.gov (United States)

    Youngsteadt, Elsa; Henderson, Ryanna C; Savage, Amy M; Ernst, Andrew F; Dunn, Robert R; Frank, Steven D

    2015-03-01

    Urban green spaces provide ecosystem services to city residents, but their management is hindered by a poor understanding of their ecology. We examined a novel ecosystem service relevant to urban public health and esthetics: the consumption of littered food waste by arthropods. Theory and data from natural systems suggest that the magnitude and resilience of this service should increase with biological diversity. We measured food removal by presenting known quantities of cookies, potato chips, and hot dogs in street medians (24 sites) and parks (21 sites) in New York City, USA. At the same sites, we assessed ground-arthropod diversity and abiotic conditions, including history of flooding during Hurricane Sandy 7 months prior to the study. Arthropod diversity was greater in parks (on average 11 hexapod families and 4.7 ant species per site), than in medians (nine hexapod families and 2.7 ant species per site). However, counter to our diversity-based prediction, arthropods in medians removed 2-3 times more food per day than did those in parks. We detected no effect of flooding (at 19 sites) on this service. Instead, greater food removal was associated with the presence of the introduced pavement ant (Tetramorium sp. E) and with hotter, drier conditions that may have increased arthropod metabolism. When vertebrates also had access to food, more was removed, indicating that arthropods and vertebrates compete for littered food. We estimate that arthropods alone could remove 4-6.5 kg of food per year in a single street median, reducing its availability to less desirable fauna such as rats. Our results suggest that species identity and habitat may be more relevant than diversity for predicting urban ecosystem services. Even small green spaces such as street medians provide ecosystem services that may complement those of larger habitat patches across the urban landscape.

  18. Reconstructing the phylogeny of 21 completely sequenced arthropod species based on their motor proteins

    Directory of Open Access Journals (Sweden)

    Kollmar Martin

    2009-04-01

    Full Text Available Abstract Background Motor proteins have extensively been studied in the past and consist of large superfamilies. They are involved in diverse processes like cell division, cellular transport, neuronal transport processes, or muscle contraction, to name a few. Vertebrates contain up to 60 myosins and about the same number of kinesins that are spread over more than a dozen distinct classes. Results Here, we present the comparative genomic analysis of the motor protein repertoire of 21 completely sequenced arthropod species using the owl limpet Lottia gigantea as outgroup. Arthropods contain up to 17 myosins grouped into 13 classes. The myosins are in almost all cases clear paralogs, and thus the evolution of the arthropod myosin inventory is mainly determined by gene losses. Arthropod species contain up to 29 kinesins spread over 13 classes. In contrast to the myosins, the evolution of the arthropod kinesin inventory is not only determined by gene losses but also by many subtaxon-specific and species-specific gene duplications. All arthropods contain each of the subunits of the cytoplasmic dynein/dynactin complex. Except for the dynein light chains and the p150 dynactin subunit they contain single gene copies of the other subunits. Especially the roadblock light chain repertoire is very species-specific. Conclusion All 21 completely sequenced arthropods, including the twelve sequenced Drosophila species, contain a species-specific set of motor proteins. The phylogenetic analysis of all genes as well as the protein repertoire placed Daphnia pulex closest to the root of the Arthropoda. The louse Pediculus humanus corporis is the closest relative to Daphnia followed by the group of the honeybee Apis mellifera and the jewel wasp Nasonia vitripennis. After this group the rust-red flour beetle Tribolium castaneum and the silkworm Bombyx mori diverged very closely from the lineage leading to the Drosophila species.

  19. Is Minocycline an Antiviral Agent? A Review of Current Literature.

    Science.gov (United States)

    Nagarakanti, Sandhya; Bishburg, Eliahu

    2016-01-01

    Minocycline is a second-generation semi-synthetic derivative of tetracycline and has well-known anti-bacterial effects. The drug possesses anti-inflammatory, anti-oxidant, anti-apoptotic and immunomodulatory effects. The drug is widely used in bacterial infections and non-infectious conditions such as acne, dermatitis, periodontitis and neurodegenerative conditions. Minocycline was shown to have antiviral activity in vitro and also against different viruses in some animal models. Some studies have been done on human patients infected with Human Immunodeficiency Virus. We have review the available data regarding minocycline activity as an antiviral agent. PMID:26177421

  20. Antiviral, antifungal and antiprotozoal agents in the cinema.

    Science.gov (United States)

    García-Sánchez, Jose Elias; García-Sánchez, E; Merino Marcos, M L

    2007-03-01

    Among the antimicrobial agents, antibacterials are the most frequently mentioned in cinematographic plots. Nevertheless, it is not uncommon to come across other antiviral agents, especially antiretrovirals and antiprotozoals. We analyzed the presence of antiviral and antifungal agents in different commercial films, both when they were merely mentioned in passing and when they played a major role in the film. This review essentially aims to address the historical portrayal of these agents in film and to list their appearances. The fictional treatments that appear in some films are not addressed.

  1. microRNA control of interferons and interferon induced anti-viral activity.

    Science.gov (United States)

    Sedger, Lisa M

    2013-12-01

    Interferons (IFNs) are cytokines that are spontaneously produced in response to virus infection. They act by binding to IFN-receptors (IFN-R), which trigger JAK/STAT cell signalling and the subsequent induction of hundreds of IFN-inducible genes, including both protein-coding and microRNA genes. IFN-induced genes then act synergistically to prevent virus replication and create an anti-viral state. miRNA are therefore integral to the innate response to virus infection and are important components of IFN-mediated biology. On the other hand viruses also encode miRNAs that in some cases interfere directly with the IFN response to infection. This review summarizes the important roles of miRNAs in virus infection acting both as IFN-stimulated anti-viral molecules and as critical regulators of IFNs and IFN-stimulated genes. It also highlights how recent knowledge in RNA editing influence miRNA control of virus infection.

  2. Oral immune regulation: a novel method for modulation of anti-viral immunity.

    Science.gov (United States)

    Margalit, Maya; Ilan, Yaron

    2004-12-01

    Chronic viral infections, including hepatitis B and C and human immunodeficiency virus (HIV) infections, afflict a significant part of the world's population. In many of these diseases, chronicity has been linked to defective anti-viral immunity that damages host tissues without producing viral clearance. Currently available therapeutic measures for chronic viral infections are limited. Oral immune regulation, the manipulation of immune responses towards antigens by their oral administration, is a relatively simple and antigen-specific immune-modulatory tool. Recent evidence suggests that induction of oral immune-regulation towards viral antigens may entail a complex immune effect, characterized by simultaneous enhancement and suppression of different elements of the immune response in a manner that benefits the host. Such manipulation of the immune response towards viruses may achieve a combination of upregulated specific anti-viral immunity and inhibition of immune-mediated damage. Oral immune regulation may prove to be an important addition to the available therapeutic arsenal for chronic viral infections. PMID:15567096

  3. Asthma is associated with multiple alterations in anti-viral innate signalling pathways.

    Directory of Open Access Journals (Sweden)

    Antonia L Pritchard

    Full Text Available BACKGROUND: Human rhinovirus (HRV infection is a major trigger for asthma exacerbations. Anti-viral immunity appears to be abnormal in asthma, with immune dysfunction reported in both airway structural cells and migratory, bone marrow derived cells. Though decreased capacity to produce anti-viral interferons (IFNs has been reported in asthma, a detailed analysis of the molecular events involved has not been undertaken. OBJECTIVE: To compare the molecular pathway controlling type I IFN synthesis in HRV-stimulated peripheral blood mononuclear cells (PBMC from asthmatic and healthy subjects. METHODS: PBMC from 22 allergic asthmatics and 20 healthy donors were cultured with HRV for 24 hours. Multiple components of the Toll-like receptor (TLR, IFN regulatory and NFκβ pathways were compared at the mRNA and protein level. RESULTS: Multiple deficiencies in the innate immune response to HRV were identified in asthma, with significantly lower expression of IFNα, IFNβ and interferon stimulated genes than in healthy subjects. This was accompanied by reduced expression of intra-cellular signalling molecules including interferon regulatory factors (IRF1, IRF7, NF-κB family members (p50, p52, p65 and IκKα and STAT1, and by reduced responsiveness to TLR7/TLR8 activation. These observations could not be attributed to alterations in the numbers of dendritic cell (DC subsets in asthma or baseline expression of the viral RNA sensing receptors TLR7/TLR8. In healthy subjects, blocking the activity of type-I IFN or depleting plasmacytoid DC recapitulated many of the abnormalities observed in asthma. CONCLUSIONS: Multiple abnormalities in innate anti-viral signalling pathways were identified in asthma, with deficiencies in both IFN-dependent and IFN-independent molecules identified.

  4. Characterization of a Novel Human-Specific STING Agonist that Elicits Antiviral Activity Against Emerging Alphaviruses.

    Directory of Open Access Journals (Sweden)

    Tina M Sali

    2015-12-01

    Full Text Available Pharmacologic stimulation of innate immune processes represents an attractive strategy to achieve multiple therapeutic outcomes including inhibition of virus replication, boosting antitumor immunity, and enhancing vaccine immunogenicity. In light of this we sought to identify small molecules capable of activating the type I interferon (IFN response by way of the transcription factor IFN regulatory factor 3 (IRF3. A high throughput in vitro screen yielded 4-(2-chloro-6-fluorobenzyl-N-(furan-2-ylmethyl-3-oxo-3,4-dihydro-2H-benzo[b][1,4]thiazine-6-carboxamide (referred to herein as G10, which was found to trigger IRF3/IFN-associated transcription in human fibroblasts. Further examination of the cellular response to this molecule revealed expression of multiple IRF3-dependent antiviral effector genes as well as type I and III IFN subtypes. This led to the establishment of a cellular state that prevented replication of emerging Alphavirus species including Chikungunya virus, Venezuelan Equine Encephalitis virus, and Sindbis virus. To define cellular proteins essential to elicitation of the antiviral activity by the compound we employed a reverse genetics approach that utilized genome editing via CRISPR/Cas9 technology. This allowed the identification of IRF3, the IRF3-activating adaptor molecule STING, and the IFN-associated transcription factor STAT1 as required for observed gene induction and antiviral effects. Biochemical analysis indicates that G10 does not bind to STING directly, however. Thus the compound may represent the first synthetic small molecule characterized as an indirect activator of human STING-dependent phenotypes. In vivo stimulation of STING-dependent activity by an unrelated small molecule in a mouse model of Chikungunya virus infection blocked viremia demonstrating that pharmacologic activation of this signaling pathway may represent a feasible strategy for combating emerging Alphaviruses.

  5. In Vitro Antiviral Activity of Clove and Ginger Aqueous Extracts against Feline Calicivirus, a Surrogate for Human Norovirus.

    Science.gov (United States)

    Aboubakr, Hamada A; Nauertz, Andrew; Luong, Nhungoc T; Agrawal, Shivani; El-Sohaimy, Sobhy A A; Youssef, Mohammed M; Goyal, Sagar M

    2016-06-01

    Foodborne viruses, particularly human norovirus, are a concern for public health, especially in fresh vegetables and other minimally processed foods that may not undergo sufficient decontamination. It is necessary to explore novel nonthermal techniques for preventing foodborne viral contamination. In this study, aqueous extracts of six raw food materials (flower buds of clove, fenugreek seeds, garlic and onion bulbs, ginger rhizomes, and jalapeño peppers) were tested for antiviral activity against feline calicivirus (FCV) as a surrogate for human norovirus. The antiviral assay was performed using dilutions of the extracts below the maximum nontoxic concentrations of the extracts to the host cells of FCV, Crandell-Reese feline kidney (CRFK) cells. No antiviral effect was seen when the host cells were pretreated with any of the extracts. However, pretreatment of FCV with nondiluted clove and ginger extracts inactivated 6.0 and 2.7 log of the initial titer of the virus, respectively. Also, significant dosedependent inactivation of FCV was seen when host cells were treated with clove and ginger extracts at the time of infection or postinfection at concentrations equal to or lower than the maximum nontoxic concentrations. By comprehensive two-dimensional gas chromatography-mass spectrometry analysis, eugenol (29.5%) and R-(-)-1,2-propanediol (10.7%) were identified as the major components of clove and ginger extracts, respectively. The antiviral effect of the pure eugenol itself was tested; it showed antiviral activity similar to that of clove extract, albeit at a lower level, which indicates that some other clove extract constituents, along with eugenol, are responsible for inactivation of FCV. These results showed that the aqueous extracts of clove and ginger hold promise for prevention of foodborne viral contamination.

  6. In Vitro Antiviral Activity of Clove and Ginger Aqueous Extracts against Feline Calicivirus, a Surrogate for Human Norovirus.

    Science.gov (United States)

    Aboubakr, Hamada A; Nauertz, Andrew; Luong, Nhungoc T; Agrawal, Shivani; El-Sohaimy, Sobhy A A; Youssef, Mohammed M; Goyal, Sagar M

    2016-06-01

    Foodborne viruses, particularly human norovirus, are a concern for public health, especially in fresh vegetables and other minimally processed foods that may not undergo sufficient decontamination. It is necessary to explore novel nonthermal techniques for preventing foodborne viral contamination. In this study, aqueous extracts of six raw food materials (flower buds of clove, fenugreek seeds, garlic and onion bulbs, ginger rhizomes, and jalapeño peppers) were tested for antiviral activity against feline calicivirus (FCV) as a surrogate for human norovirus. The antiviral assay was performed using dilutions of the extracts below the maximum nontoxic concentrations of the extracts to the host cells of FCV, Crandell-Reese feline kidney (CRFK) cells. No antiviral effect was seen when the host cells were pretreated with any of the extracts. However, pretreatment of FCV with nondiluted clove and ginger extracts inactivated 6.0 and 2.7 log of the initial titer of the virus, respectively. Also, significant dosedependent inactivation of FCV was seen when host cells were treated with clove and ginger extracts at the time of infection or postinfection at concentrations equal to or lower than the maximum nontoxic concentrations. By comprehensive two-dimensional gas chromatography-mass spectrometry analysis, eugenol (29.5%) and R-(-)-1,2-propanediol (10.7%) were identified as the major components of clove and ginger extracts, respectively. The antiviral effect of the pure eugenol itself was tested; it showed antiviral activity similar to that of clove extract, albeit at a lower level, which indicates that some other clove extract constituents, along with eugenol, are responsible for inactivation of FCV. These results showed that the aqueous extracts of clove and ginger hold promise for prevention of foodborne viral contamination. PMID:27296605

  7. Aktivitas Antiviral Minyak Atsiri Jahe Merah terhadap Virus Flu Burung (ANTIVIRAL ACTIVITY OF ESSENSIAL OIL RED GINGER ON AVIAN INFLUENZA

    Directory of Open Access Journals (Sweden)

    Tri Untari

    2013-07-01

    Full Text Available The studies have reported that ginger have many activities such as antiemesis, anti-inflammatory,anti-bacterial and anti-parasites. Therefore, this study was conducted to evaluate antiviral effect of essentialred ginger oil againts Avian Influenza (AI in ovo using hemagglutination test (HA. Avian Influenzaviruses were treated with 0,01%, 0,1% and 1% of essential red ginger oil, and then inoculated in chickenembryonated egg via allantoic sac. Allantoic fluid was harvested using for HA test . Result of this studyshows that application of 1% of essential red ginger oil results in the reduction of titer HA . Interestingly,essential oil shows antiviral activity revealed HA titre 20 whereas the titre HA AI which AI virus treatedwith 0,01% and 0,1% essential red ginger oil, the HA titer was 25. The conclution of this study proved thatessensial oil 1% of the red gingger is the best concentration as antiviral activity .

  8. DMPD: The interferon in TLR signaling: more than just antiviral. [Dynamic Macrophage Pathway CSML Database

    Lifescience Database Archive (English)

    Full Text Available 14552837 The interferon in TLR signaling: more than just antiviral. Hertzog PJ, O'N...on in TLR signaling: more than just antiviral. PubmedID 14552837 Title The interferon in TLR signaling: more than just anti

  9. Modification and Application of a Leaf Blower-vac for Field Sampling of Arthropods.

    Science.gov (United States)

    Zou, Yi; van Telgen, Mario D; Chen, Junhui; Xiao, Haijun; de Kraker, Joop; Bianchi, Felix J J A; van der Werf, Wopke

    2016-01-01

    Rice fields host a large diversity of arthropods, but investigating their population dynamics and interactions is challenging. Here we describe the modification and application of a leaf blower-vac for suction sampling of arthropod populations in rice. When used in combination with an enclosure, application of this sampling device provides absolute estimates of the populations of arthropods as numbers per standardized sampling area. The sampling efficiency depends critically on the sampling duration. In a mature rice crop, a two-minute sampling in an enclosure of 0.13 m(2) yields more than 90% of the arthropod population. The device also allows sampling of arthropods dwelling on the water surface or the soil in rice paddies, but it is not suitable for sampling fast flying insects, such as predatory Odonata or larger hymenopterous parasitoids. The modified blower-vac is simple to construct, and cheaper and easier to handle than traditional suction sampling devices, such as D-vac. The low cost makes the modified blower-vac also accessible to researchers in developing countries. PMID:27584040

  10. Evaluation of Ground Arthropod Structure in Restoration Area of Talangagung Landfill as Edutourism Attraction, Kepanjen, Malang

    Directory of Open Access Journals (Sweden)

    Dinda Azalia

    2015-09-01

    Full Text Available Aim of this research is to know the composition, community structure and survivality of ground arthropod in restoration area of Talangagung edutourism landfill (TPA Wisata Edukasi Talangagung. Arthopod survey was conducted with four methods, yellow pan trap, pit fall trap, berlesetullgren, and sweep net. The research was done in four different locations with twice repetition. Survey location was devided in three zone, which is zone one with 10 years restoration, zone two with five years restoration, and zone three which not yet restored, and reference site. Abiotic factor which observed in this research such as light intensity, humidity, and air temperature. Analysis of arthropod diversity and community structure in each site was calculated from importance value index (IVI and diversity index (Shannon Wienner Index. The results show that diversity of ground arthropod in zone one, two, three, and reference site was on medium level which each score 1.9, 1.87, 1.71, and 2.08. Community structure with dominant pattern showed with IVI from Acrididae in zone one and zone three with IVI 67.2 % and 53.5 %. Myrmicidae in reference site dominance with IVI 51.4 % and Formicidae in zone one with IVI 48.6 %. Ground arthropod in zone one and reference site had similarity in community structure which showed in same cluster in biplot analysis and zone two and three was in another different cluster. Keywords : Arthropod, diversity, restoration, community structure

  11. Disturbance and recovery of salt marsh arthropod communities following BP Deepwater Horizon oil spill.

    Directory of Open Access Journals (Sweden)

    Brittany D McCall

    Full Text Available Oil spills represent a major environmental threat to coastal wetlands, which provide a variety of critical ecosystem services to humanity. The U.S. Gulf of Mexico is a hub of oil and gas exploration activities that historically have impacted intertidal habitats such as salt marsh. Following the BP Deepwater Horizon oil spill, we sampled the terrestrial arthropod community and marine invertebrates found in stands of Spartina alterniflora, the most abundant plant in coastal salt marshes. Sampling occurred in 2010 as oil was washing ashore and a year later in 2011. In 2010, intertidal crabs and terrestrial arthropods (insects and spiders were suppressed by oil exposure even in seemingly unaffected stands of plants; however, Littoraria snails were unaffected. One year later, crab and arthropods had largely recovered. Our work is the first attempt that we know of assessing vulnerability of the salt marsh arthropod community to oil exposure, and it suggests that arthropods are both quite vulnerable to oil exposure and quite resilient, able to recover from exposure within a year if host plants remain healthy.

  12. Health-related quality of life and impact of antiviral treatment in Chinese patients with chronic hepatitis C in Taiwan

    Institute of Scientific and Technical Information of China (English)

    Shih-Chao Kang; Shinn-Jang Hwang; Shiang-Ho Lee; Full-Young Chang; Shou-Dong Lee

    2005-01-01

    AIM: To evaluate health-related quality of life (HRQOL) in Chinese patients with chronic hepatitis C (CH-C), and the impact of antiviral treatment.METHODS: Short Form 36 (SF-36) Health-related Quality of Life Questionnaires to interview CH-C patients, and age- and sex-matched control subjects at outpatient clinics of a medical center in Taiwan were used. Data were transformed to scores for comparisons of eight major SF-36 domains. We also enrolled consecutive CH-C patients who completed one course of antiviral treatment(interferon α with ribavirin), and measured the HRQOLbefore, at the 12th wk of treatment, at the end of treatment, and at mo 6, after stopping the treatment to evaluate the impact of antiviral treatment.RESULTS: A total of 371 outpatients were enrolled, including 182 with CH-C and 189 age- and sex-matched subjects without CH-C. CH-C subjects had obviously lower educational status (P<0.01). Mean scores of domains in general health, physical functioning, role-physical,role-emotional, vitality, and mental health of the SF-36 were significantly lower in subjects with CH-C than those without CH-C (P<0.05). In an analysis of 47 CH-C patients who received and completed the whole course of antiviral treatment, mean scores of all domains were significantly lower at wk 12 of treatment compared to baseline. The scores returned to pretreatment values by the end of treatment, but were significantly increased at mo 6 after stopping the treatment. Among the 47 CH-C patients, 21 had sustained responses and 26 had nonsustained responses to antiviral treatment. Compared to pretreatment values, subjects with sustained responses had significantly lower social functioning scores at wk 12 of treatment, and scores for all SF-36 domains returned to pretreatment values, and increased significantly at mo 6 after stopping the treatment. For non-sustained virological responders, scores of all SF-36 domains significantly decreased at wk 12 of treatment, and did not increase

  13. DMPD: Negative regulation of cytoplasmic RNA-mediated antiviral signaling. [Dynamic Macrophage Pathway CSML Database

    Lifescience Database Archive (English)

    Full Text Available 18703349 Negative regulation of cytoplasmic RNA-mediated antiviral signaling. Komur...Show Negative regulation of cytoplasmic RNA-mediated antiviral signaling. PubmedID 18703349 Title Negative r...egulation of cytoplasmic RNA-mediated antiviral signaling. Authors Komuro A, Bamm

  14. DMPD: What is disrupting IFN-alpha's antiviral activity? [Dynamic Macrophage Pathway CSML Database

    Lifescience Database Archive (English)

    Full Text Available 15283983 What is disrupting IFN-alpha's antiviral activity? Mbow ML, Sarisky RT. Tr...ends Biotechnol. 2004 Aug;22(8):395-9. (.png) (.svg) (.html) (.csml) Show What is disrupting IFN-alpha's antiviral activity...? PubmedID 15283983 Title What is disrupting IFN-alpha's antiviral activity? Authors Mbow ML,

  15. DMPD: Regulation of mitochondrial antiviral signaling pathways. [Dynamic Macrophage Pathway CSML Database

    Lifescience Database Archive (English)

    Full Text Available 18549796 Regulation of mitochondrial antiviral signaling pathways. Moore CB, Ting J...P. Immunity. 2008 Jun;28(6):735-9. (.png) (.svg) (.html) (.csml) Show Regulation of mitochondrial antiviral signaling path...ways. PubmedID 18549796 Title Regulation of mitochondrial antiviral signaling pathways. Author

  16. DMPD: TLR3 in antiviral immunity: key player or bystander? [Dynamic Macrophage Pathway CSML Database

    Lifescience Database Archive (English)

    Full Text Available 16027039 TLR3 in antiviral immunity: key player or bystander? Schroder M, Bowie AG.... Trends Immunol. 2005 Sep;26(9):462-8. (.png) (.svg) (.html) (.csml) Show TLR3 in antiviral immunity: key pl...ayer or bystander? PubmedID 16027039 Title TLR3 in antiviral immunity: key player or bystander? Authors Schr

  17. Pharmacogenetics of hepatitis C: transition from interferon-based therapies to direct-acting antiviral agents

    Directory of Open Access Journals (Sweden)

    Kamal SM

    2014-06-01

    Full Text Available Sanaa M Kamal1,21Department of Medicine, Division of Hepatology, Gastroenterology and Tropical Medicine, Ain Shams Faculty of Medicine, Cairo, Egypt, 2Department of Medicine, Salman Bin Abdul Aziz College of Medicine, Kingdom of Saudi ArabiaAbstract: Hepatitis C virus (HCV has emerged as a major viral pandemic over the past two decades, infecting 170 million individuals, which equates to approximately 3% of the world's population. The prevalence of HCV varies according to geographic region, being highest in developing countries such as Egypt. HCV has a high tendency to induce chronic progressive liver damage in the form of hepatic fibrosis, cirrhosis, or liver cancer. To date, there is no vaccine against HCV infection. Combination therapy comprising PEGylated interferon-alpha and ribavirin has been the standard of care for patients with chronic hepatitis C for more than a decade. However, many patients still do not respond to therapy or develop adverse events. Recently, direct antiviral agents such as protease inhibitors, polymerase inhibitors, or NS5A inhibitors have been used to augment PEGylated interferon and ribavirin, resulting in better efficacy, better tolerance, and a shorter treatment duration. However, most clinical trials have focused on assessing the efficacy and safety of direct antiviral agents in patients with genotype 1, and the response of other HCV genotypes has not been elucidated. Moreover, the prohibitive costs of such triple therapies will limit their use in patients in developing countries where most of the HCV infection exists. Understanding the host and viral factors associated with viral clearance is necessary for individualizing therapy to maximize sustained virologic response rates, prevent progression to liver disease, and increase the overall benefits of therapy with respect to its costs. Genome wide studies have shown significant associations between a set of polymorphisms in the region of the interleukin-28B (IL

  18. H1N1 Flu and Antiviral Drugs

    Centers for Disease Control (CDC) Podcasts

    2009-05-02

    This podcast discusses the use of antiviral drugs for treating and preventing the H1N1 flu virus.  Created: 5/2/2009 by Coordinating Center for Infectious Diseases, National Center for Immunization and Respiratory Diseases, Influenza Division (CCID/NCIRD/ID).   Date Released: 5/2/2009.

  19. Evaluation of antiseptic antiviral activity of chemical agents.

    Science.gov (United States)

    Geller, Chloé; Finance, Chantal; Duval, Raphaël Emmanuel

    2011-06-01

    Antiviral antisepsis and disinfection are crucial for preventing the environmental spread of viral infections. Emerging viruses and associated diseases, as well as nosocomial viral infections, have become a real issue in medical fields, and there are very few efficient and specific treatments available to fight most of these infections. Another issue is the potential environmental resistance and spread of viral particles. Therefore, it is essential to properly evaluate the efficacy of antiseptics-disinfectants (ATS-D) on viruses. ATS-D antiviral activity is evaluated by (1) combining viruses and test product for an appropriately defined and precise contact time, (2) neutralizing product activity, and (3) estimating the loss of viral infectivity. A germicide can be considered to have an efficient ATS-D antiviral activity if it induces a >3 or >4 log(10) reduction (American and European regulatory agency requirements, respectively) in viral titers in a defined contact time. This unit describes a global methodology for evaluating chemical ATS-D antiviral activity.

  20. INVESTMENT IN ANTIVIRAL DRUGS : A REAL OPTIONS APPROACH

    NARCIS (Netherlands)

    Attema, Arthur E.; Lugner, Anna K.; Feenstra, Talitha L.

    2010-01-01

    Real options analysis is a promising approach to model investment under uncertainty. We employ this approach to value stockpiling of antiviral drugs as a precautionary measure against a possible influenza pandemic. Modifications of the real options approach to include risk attitude and deviations fr

  1. Small molecules with antiviral activity against the Ebola virus.

    Science.gov (United States)

    Litterman, Nadia; Lipinski, Christopher; Ekins, Sean

    2015-01-01

    The recent outbreak of the Ebola virus in West Africa has highlighted the clear shortage of broad-spectrum antiviral drugs for emerging viruses. There are numerous FDA approved drugs and other small molecules described in the literature that could be further evaluated for their potential as antiviral compounds. These molecules are in addition to the few new antivirals that have been tested in Ebola patients but were not originally developed against the Ebola virus, and may play an important role as we await an effective vaccine. The balance between using FDA approved drugs versus novel antivirals with minimal safety and no efficacy data in humans should be considered. We have evaluated 55 molecules from the perspective of an experienced medicinal chemist as well as using simple molecular properties and have highlighted 16 compounds that have desirable qualities as well as those that may be less desirable. In addition we propose that a collaborative database for sharing such published and novel information on small molecules is needed for the research community studying the Ebola virus. PMID:25713700

  2. Adenovirus infection reverses the antiviral state induced by human interferon.

    Science.gov (United States)

    Feduchi, E; Carrasco, L

    1987-04-01

    HeLa cells treated with human lymphoblastoid interferon do not synthesize poliovirus proteins. The antiviral state against poliovirus is reversed if cells are previously infected with adenovirus type 5. A late gene product seems to be involved in this reversion, since no effect is observed at early stages of infection or in the presence of aphidicolin.

  3. Liposomal Systems as Nanocarriers for the Antiviral Agent Ivermectin.

    Science.gov (United States)

    Croci, Romina; Bottaro, Elisabetta; Chan, Kitti Wing Ki; Watanabe, Satoru; Pezzullo, Margherita; Mastrangelo, Eloise; Nastruzzi, Claudio

    2016-01-01

    RNA virus infections can lead to the onset of severe diseases such as fever with haemorrhage, multiorgan failure, and mortality. The emergence and reemergence of RNA viruses continue to pose a significant public health threat worldwide with particular attention to the increasing incidence of flaviviruses, among others Dengue, West Nile Virus, and Yellow Fever viruses. Development of new and potent antivirals is thus urgently needed. Ivermectin, an already known antihelminthic drug, has shown potent effects in vitro on Flavivirus helicase, with EC50 values in the subnanomolar range for Yellow Fever and submicromolar EC50 for Dengue Fever, Japanese encephalitis, and tick-borne encephalitis viruses. However ivermectin is hampered in its application by pharmacokinetic problems (little solubility and high cytotoxicity). To overcome such problems we engineered different compositions of liposomes as ivermectin carriers characterizing and testing them on several cell lines for cytotoxicity. The engineered liposomes were less cytotoxic than ivermectin alone and they showed a significant increase of the antiviral activity in all the Dengue stains tested (1, 2, and S221). In the current study ivermectin is confirmed to be an effective potential antiviral and liposomes, as drug carriers, are shown to modulate the drug activity. All together the results represent a promising starting point for future improvement of ivermectin as antiviral and its delivery. PMID:27242902

  4. Antiviral medication in sexually transmitted diseases. Part I: HSV, HPV.

    Science.gov (United States)

    Mlynarczyk-Bonikowska, Beata; Majewska, Anna; Malejczyk, Magdalena; Mlynarczyk, Grazyna; Majewski, Slawomir

    2013-11-01

    Sexually transmitted diseases (STD) are one of the most prevalent infectious diseases in the world and important cause of morbidity and mortality. Especially STDs of viral etiology are difficult to cure. In many cases the antiviral therapy can relieve the symptoms but not eliminate the virus. During the past decades, considerable progress has been made in the development of antiviral drugs. One of the oldest antiviral medications is acyclovir (ACV). It is approved to treat initial and recurrent genital herpes and as a suppressive therapy in severe recurrent genital infections as well. Drug resistance to ACV and related drugs is seen among immunocompromised hosts, including human immunodeficiency virus HIV-infected patients. Resistant infections can be managed by second-line drugs - foscarnet or cidofovir- but they are more toxic than ACV. In case of HPV there is not known specific target for the medication and that is why the substances used in human papilloma virus HPV infection therapy are either antimitotics or immunomodulators. The Part I review focuses on mechanisms of actions and mechanisms of resistance to antiviral agents used in a treatment of the genital herpes and genital HPV infection. In Part II we will show the therapeutic options in other sexually transmitted infections: hepatitis B, C and HIV. PMID:24032509

  5. Liposomal Systems as Nanocarriers for the Antiviral Agent Ivermectin

    Directory of Open Access Journals (Sweden)

    Romina Croci

    2016-01-01

    Full Text Available RNA virus infections can lead to the onset of severe diseases such as fever with haemorrhage, multiorgan failure, and mortality. The emergence and reemergence of RNA viruses continue to pose a significant public health threat worldwide with particular attention to the increasing incidence of flaviviruses, among others Dengue, West Nile Virus, and Yellow Fever viruses. Development of new and potent antivirals is thus urgently needed. Ivermectin, an already known antihelminthic drug, has shown potent effects in vitro on Flavivirus helicase, with EC50 values in the subnanomolar range for Yellow Fever and submicromolar EC50 for Dengue Fever, Japanese encephalitis, and tick-borne encephalitis viruses. However ivermectin is hampered in its application by pharmacokinetic problems (little solubility and high cytotoxicity. To overcome such problems we engineered different compositions of liposomes as ivermectin carriers characterizing and testing them on several cell lines for cytotoxicity. The engineered liposomes were less cytotoxic than ivermectin alone and they showed a significant increase of the antiviral activity in all the Dengue stains tested (1, 2, and S221. In the current study ivermectin is confirmed to be an effective potential antiviral and liposomes, as drug carriers, are shown to modulate the drug activity. All together the results represent a promising starting point for future improvement of ivermectin as antiviral and its delivery.

  6. Bilirubin: an endogenous molecule with antiviral activity in vitro.

    Directory of Open Access Journals (Sweden)

    Rosaria eSantangelo

    2012-03-01

    Full Text Available Bilirubin-IX-alpha (BR is the final product of heme metabolism through the heme oxygenase/biliverdin reductase (HO/BVR system. Previous papers reported on the microbicidal effects of the HO by-products biliverdin-IX-alpha, carbon monoxide and iron, through either direct or indirect mechanisms. In this paper the evidence of a virucidal effect of BR against human herpes simplex virus type 1 (HSV-1 and the enterovirus EV71 was provided. Bilirubin-IX-alpha, at concentrations 1-10 µM, close to those found in blood and tissues, significantly reduced HSV-1 and EV71 replication in Hep-2 and Vero cell lines, respectively. Bilirubin-IX-alpha inhibited viral infection of Hep-2 and Vero cells when given 2 hours before, concomitantly and 2 hours after viral infection. Furthermore, BR retained its antiviral activity even complexed with a saturating concentration of human serum-albumin. Moreover, 10 µM BR increased the formation of nitric oxide and the phosphorylation of JNK in Vero and Hep-2 cell lines, respectively, thus implying a role of these two pathways in the mechanism of antiviral activity of the bile pigment. In conclusion, these results support the antiviral effect of BR against HSV-1 and enterovirus in vitro, and put the basis for further basic and clinical studies to understand the real role of BR as an endogenous antiviral molecule.

  7. Approved Antiviral Drugs over the Past 50 Years.

    Science.gov (United States)

    De Clercq, Erik; Li, Guangdi

    2016-07-01

    Since the first antiviral drug, idoxuridine, was approved in 1963, 90 antiviral drugs categorized into 13 functional groups have been formally approved for the treatment of the following 9 human infectious diseases: (i) HIV infections (protease inhibitors, integrase inhibitors, entry inhibitors, nucleoside reverse transcriptase inhibitors, nonnucleoside reverse transcriptase inhibitors, and acyclic nucleoside phosphonate analogues), (ii) hepatitis B virus (HBV) infections (lamivudine, interferons, nucleoside analogues, and acyclic nucleoside phosphonate analogues), (iii) hepatitis C virus (HCV) infections (ribavirin, interferons, NS3/4A protease inhibitors, NS5A inhibitors, and NS5B polymerase inhibitors), (iv) herpesvirus infections (5-substituted 2'-deoxyuridine analogues, entry inhibitors, nucleoside analogues, pyrophosphate analogues, and acyclic guanosine analogues), (v) influenza virus infections (ribavirin, matrix 2 protein inhibitors, RNA polymerase inhibitors, and neuraminidase inhibitors), (vi) human cytomegalovirus infections (acyclic guanosine analogues, acyclic nucleoside phosphonate analogues, pyrophosphate analogues, and oligonucleotides), (vii) varicella-zoster virus infections (acyclic guanosine analogues, nucleoside analogues, 5-substituted 2'-deoxyuridine analogues, and antibodies), (viii) respiratory syncytial virus infections (ribavirin and antibodies), and (ix) external anogenital warts caused by human papillomavirus infections (imiquimod, sinecatechins, and podofilox). Here, we present for the first time a comprehensive overview of antiviral drugs approved over the past 50 years, shedding light on the development of effective antiviral treatments against current and emerging infectious diseases worldwide. PMID:27281742

  8. Flu Resistance to Antiviral Drug in North Carolina

    Centers for Disease Control (CDC) Podcasts

    2011-12-19

    Dr. Katrina Sleeman, Associate Service Fellow at CDC, discusses resistance to an antiviral flu drug in North Carolina.  Created: 12/19/2011 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID).   Date Released: 12/19/2011.

  9. Hepatitis C virus lymphotropism and peculiar immunological phenotype: Effects on natural history and antiviral therapy

    Institute of Scientific and Technical Information of China (English)

    Paolo Conca; Giovanni Tarantino

    2009-01-01

    Hepatitis C virus (HCV) has been recognized to be both a hepato- and lymphotropic virus. HCV lymphotropism represents an essential lap in the pathogenesis of virusrelated autoimmune and lymphoproliferative disorders, ranging from clonal expansion of B-cells with organ-and non-organ-specific autoantibody production up step-by-step model of B-cell lymphomagenesis, where the intermediated mixed cryoglobulinemia could be considered as a stage of suppressible antigen-driven lymphoproliferation. HCV infection of lymphoid cells could set up privileged reservoirs able to interfere with the host viral clearance efficiency and may be implicated in viral recurrence after apparently successful antiviral therapy. The HCV long-lasting extrahepatic replicative state generates an abnormal systemic immunological response, easily detectable by searching simple laboratory and clinical parameters, mainly represented by vasculitis-like skin features and hypocomplementemia.The presence or absence of this hypersensitivity pattern seems to correlate with the antiviral response and could be identified as a novel immunological cofactor. Further research is required to fully verify the real impact on therapeutic choice/regimen.

  10. Tiny individuals attached to a new Silurian arthropod suggest a unique mode of brood care

    Science.gov (United States)

    Briggs, Derek E. G.; Siveter, Derek J.; Siveter, David J.; Sutton, Mark D.

    2016-04-01

    The ˜430-My-old Herefordshire, United Kingdom, Lagerstätte has yielded a diversity of remarkably preserved invertebrates, many of which provide fundamental insights into the evolutionary history and ecology of particular taxa. Here we report a new arthropod with 10 tiny arthropods tethered to its tergites by long individual threads. The head of the host, which is covered by a shield that projects anteriorly, bears a long stout uniramous antenna and a chelate limb followed by two biramous appendages. The trunk comprises 11 segments, all bearing limbs and covered by tergites with long slender lateral spines. A short telson bears long parallel cerci. Our phylogenetic analysis resolves the new arthropod as a stem-group mandibulate. The evidence suggests that the tethered individuals are juveniles and the association represents a complex brooding behavior. Alternative possibilities—that the tethered individuals represent a different epizoic or parasitic arthropod—appear less likely.

  11. A framework for assessment and monitoring of arthropods in a lowland tropical forest.

    Science.gov (United States)

    Finnamore, Albert; Alonso, Alfonso; Santisteban, Jose; Cordova, Saida; Valencia, Gorky; de la Cruz, Alicia; Polo, Roberto

    2002-05-01

    By applying principles of adaptive management, and by using the valuable information that arthropods provide from assessment and monitoring programs, managers can identify and reduce possible impacts on biodiversity in development projects. In 1996, the Smithsonian Institution's Monitoring and Assessment of Biodiversity program worked together with Shell Prospecting and Development Peru to establish an adaptive management program to protect biodiversity in a natural gas exploration project in a Peruvian rainforest. In this paper, we outlined the conceptual steps involved in establishing an assessment and monitoring program for arthropods, including setting objectives, evaluating the results and making decisions. We also present the results of the assessment using some of groups of arthropods, and summarize the steps taken to identify appropriate groups for monitoring. PMID:12125749

  12. Spatial dynamics of understorey insectivorous birds and arthropods in a southeastern Brazilian Atlantic woodlot.

    Science.gov (United States)

    Manhães, M A; Dias, M M

    2011-02-01

    Spatial distribution and spatial relationships in capture rates of understorey insectivorous birds and density of arthropods were investigated in a patch of upper montane rain forest in Minas Gerais state, southeastern Brazil, from January to December 2004. The composition of the arthropod fauna collected was similar to that reported for other tropical forests, with predominance of Araneae, Coleoptera, Hymenoptera and Hemiptera non-Heteroptera. A total of 26 bird species were captured, among which the more common were Dysithamnus mentalis, Conopophaga lineata, Platyrinchus mystaceus, Basileuterus culicivorus and Sclerurus scansor. Variation in the bird capture rates among sampling net lines were not correlated with arthropod density. Rather, individual analyses of some bird species suggest that spatial distribution of understorey insectivorous birds is better explained by habitat type. PMID:21437393

  13. Antiviral function of grouper MDA5 against iridovirus and nodavirus.

    Science.gov (United States)

    Huang, Youhua; Yu, Yepin; Yang, Ying; Yang, Min; Zhou, Linli; Huang, Xiaohong; Qin, Qiwei

    2016-07-01

    Melanoma differentiation-associated gene 5 (MDA5) is a critical member of retinoic acid-inducible gene I (RIG-I)-like receptor (RLR) family which can recognize viral RNA and enhances antiviral response in host cells. In this study, a MDA5 homolog from orange spotted grouper (Epinephelus coioides) (EcMDA5) was cloned, and its roles on grouper virus infection were characterized. The full-length EcMDA5 cDNA encoded a polypeptide of 982 amino acids with 74% identity with MDA5 homolog from rock bream (Oplegnathus fasciatus). Amino acid alignment analysis indicated that EcMDA5 contained three functional domains: two caspase activation and recruitment domain (CARDs), a DEAD box helicase-like (DExDc) domain, a helicase superfamily C-terminal domain (HELICc), and a C-terminal regulatory domain (RD). Upon challenge with Singapore grouper iridovirus (SGIV) or polyinosin-polycytidylic acid (poly I:C), the transcript of EcMDA5 was significantly up-regulated especially at the early stage post-injection. Under fluorescence microscopy, we observed that EcMDA5 mostly localized in the cytoplasm of grouper spleen (GS) cells. Interestingly, during virus infection, the distribution pattern of EcMDA5 was significantly altered in SGIV infected cells, but not in red spotted grouper nervous necrosis virus (RGNNV) infected cells, suggested that EcMDA5 might interact with viral proteins during SGIV infection. The ectopic expression of EcMDA5 in vitro obviously delayed virus infection induced cytopathic effect (CPE) progression and significantly inhibited viral gene transcription of RGNNV and SGIV. Moreover, overexpression of EcMDA5 not only significantly increased interferon (IFN) and IFN-stimulated response element (ISRE) promoter activities in a dose dependent manner, but also enhanced the expression of IRF3, IRF7 and TRAF6. In addition, the transcription level of the proinflammatory factors, including TNF-α, IL-6 and IL-8 were differently altered by EcMDA5 overexpression during SGIV or

  14. Antiviral effect of methylated flavonol isorhamnetin against influenza.

    Directory of Open Access Journals (Sweden)

    Ahmed Abdal Dayem

    Full Text Available Influenza is an infectious respiratory disease with frequent seasonal epidemics that causes a high rate of mortality and morbidity in humans, poultry, and animals. Influenza is a serious economic concern due to the costly countermeasures it necessitates. In this study, we compared the antiviral activities of several flavonols and other flavonoids with similar, but distinct, hydroxyl or methyl substitution patterns at the 3, 3', and 4' positions of the 15-carbon flavonoid skeleton, and found that the strongest antiviral effect was induced by isorhamnetin. Similar to quercetin and kaempferol, isorhamnetin possesses a hydroxyl group on the C ring, but it has a 3'-methyl group on the B ring that is absent in quercetin and kaempferol. Co-treatment and pre-treatment with isorhamnetin produced a strong antiviral effect against the influenza virus A/PR/08/34(H1N1. However, isorhamnetin showed the most potent antiviral potency when administered after viral exposure (post-treatment method in vitro. Isorhamnetin treatment reduced virus-induced ROS generation and blocked cytoplasmic lysosome acidification and the lipidation of microtubule associated protein1 light chain 3-B (LC3B. Oral administration of isorhamnetin in mice infected with the influenza A virus significantly decreased lung virus titer by 2 folds, increased the survival rate which ranged from 70-80%, and decreased body weight loss by 25%. In addition, isorhamnetin decreased the virus titer in ovo using embryonated chicken eggs. The structure-activity relationship (SAR of isorhamnetin could explain its strong anti-influenza virus potency; the methyl group located on the B ring of isorhamnetin may contribute to its strong antiviral potency against influenza virus in comparison with other flavonoids.

  15. Isomin: a novel cytoplasmic intermediate filament protein from an arthropod species

    Directory of Open Access Journals (Sweden)

    Lupetti Pietro

    2011-02-01

    Full Text Available Abstract Background The expression of intermediate filaments (IFs is a hallmark feature of metazoan cells. IFs play a central role in cell organization and function, acting mainly as structural stress-absorbing elements. There is growing evidence to suggest that these cytoskeletal elements are also involved in the integration of signalling networks. According to their fundamental functions, IFs show a widespread phylogenetic expression, from simple diblastic animals up to mammals, and their constituent proteins share the same molecular organization in all species so far analysed. Arthropods represent a major exception in this scenario. Only lamins, the nuclear IF proteins, have so far been identified in the model organisms analysed; on this basis, it has been considered that arthropods do not express cytoplasmic IFs. Results Here, we report the first evidence for the expression of a cytoplasmic IF protein in an arthropod - the basal hexapod Isotomurus maculatus. This new protein, we named it isomin, is a component of the intestinal terminal web and shares with IFs typical biochemical properties, molecular features and reassembly capability. Sequence analysis indicates that isomin is mostly related to the Intermediate Filament protein C (IFC subfamily of Caenorhabditis elegans IF proteins, which are molecular constituents of the nematode intestinal terminal web. This finding is coherent with, and provides further support to, the most recent phylogenetic views of arthropod ancestry. Interestingly, the coil 1a domain of isomin appears to have been influenced by a substantial molecular drift and only the aminoterminal part of this domain, containing the so-called helix initiation motif, has been conserved. Conclusions Our results set a new basis for the analysis of IF protein evolution during arthropod phylogeny. In the light of this new information, the statement that the arthropod phylum lacks cytoplasmic IFs is no longer tenable. See commentary

  16. Elevated atmospheric CO2 alters the arthropod community in a forest understory

    Science.gov (United States)

    Hamilton, Jason; Zangerl, Arthur R.; Berenbaum, May R.; Sparks, Jed P.; Elich, Lauren; Eisenstein, Alissa; DeLucia, Evan H.

    2012-08-01

    The objective of this study was to determine the extent to which overall population sizes and community composition of arthropods in a naturally occurring forest understory are altered by elevated CO2. The Free Air Concentration Enrichment (FACE) method was used to fumigate large, replicated plots in the Piedmont region of North Carolina, USA to achieve the CO2 concentration predicted for 2050 (˜580 μl l-1). In addition, the extent to which unrestricted herbivorous arthropods were spatially delimited in their resource acquisition was determined. Stable isotope data for spiders (δ13C and δ15N) were collected in ambient and elevated CO2 plots and analyzed to determine whether their prey species moved among plots. Elevated CO2 had no effect on total arthropod numbers but had a large effect on the composition of the arthropod community. Insects collected in our samples were identified to a level that allowed for an assignment of trophic classification (generally to family). For the groups of insects sensitive to atmospheric gas composition, there was an increase in the numbers of individuals collected in primarily predaceous orders (Araneae and Hymenoptera; from 60% to more than 150%) under elevated CO2 and a decrease in the numbers in primarily herbivorous orders (Lepidoptera and Coleoptera; from -30 to -45%). Isotopic data gave no indication that the treatment plots represented a "boundary" to the movement of insects or that there were distinct and independent insect populations inside and outside the treatment plots. A simple two-ended mixing model estimates 55% of the carbon and nitrogen in spider biomass originated external to the elevated CO2 plots. In addition to changes in insect performance, decreases in herbivorous arthropods and increases in predaceous arthropods may also be factors involved in reduced herbivory under elevated CO2 in this forest.

  17. Feeding and the rhodopsin family G-Protein Coupled Receptors (GPCRs in nematodes and arthropods

    Directory of Open Access Journals (Sweden)

    Joao Carlos dos Reis Cardoso

    2012-12-01

    Full Text Available In vertebrates, receptors of the rhodopsin G-protein coupled superfamily (GPCRs play an important role in the regulation of feeding and energy homeostasis and are activated by peptide hormones produced in the brain-gut axis. These peptides regulate appetite and energy expenditure by promoting or inhibiting food intake. Sequence and function homologues of human GPCRs involved in feeding exist in the nematode roundworm, Caenorhabditis elegans (C. elegans and the arthropod fruit fly, Drosophila melanogaster (D. melanogaster, suggesting that the mechanisms that regulate food intake emerged early and have been conserved during metazoan radiation. Nematodes and arthropods are the most diverse and successful animal phyla on Earth. They can survive in a vast diversity of environments and have acquired distinct life styles and feeding strategies. The aim of the present review is to investigate if this diversity has affected the evolution of invertebrate GPCRs. Homologues of the C. elegans and D. melanogaster rhodopsin receptors were characterized in the genome of other nematodes and arthropods and receptor evolution compared. With the exception of bombesin receptors (BBR that are absent from nematodes, a similar gene complement was found. In arthropods, rhodopsin GPCR evolution is characterized by species-specific gene duplications and deletions and in nematodes by gene expansions in species with a free-living stage and gene deletions in representatives of obligate parasitic taxa. Based upon variation in GPCR gene number and potentially divergent functions within phyla we hypothesize that life style and feeding diversity practiced by nematodes and arthropods was one factor that contributed to rhodopsin GPCR gene evolution. Understanding how the regulation of food intake has evolved in invertebrates will contribute to the development of novel drugs to control nematodes and arthropods and the pests and diseases that use them as vectors.

  18. Feeding and the rhodopsin family g-protein coupled receptors in nematodes and arthropods.

    Science.gov (United States)

    Cardoso, João C R; Félix, Rute C; Fonseca, Vera G; Power, Deborah M

    2012-01-01

    In vertebrates, receptors of the rhodopsin G-protein coupled superfamily (GPCRs) play an important role in the regulation of feeding and energy homeostasis and are activated by peptide hormones produced in the brain-gut axis. These peptides regulate appetite and energy expenditure by promoting or inhibiting food intake. Sequence and function homologs of human GPCRs involved in feeding exist in the nematode roundworm, Caenorhabditis elegans (C. elegans), and the arthropod fruit fly, Drosophila melanogaster (D. melanogaster), suggesting that the mechanisms that regulate food intake emerged early and have been conserved during metazoan radiation. Nematodes and arthropods are the most diverse and successful animal phyla on Earth. They can survive in a vast diversity of environments and have acquired distinct life styles and feeding strategies. The aim of the present review is to investigate if this diversity has affected the evolution of invertebrate GPCRs. Homologs of the C. elegans and D. melanogaster rhodopsin receptors were characterized in the genome of other nematodes and arthropods and receptor evolution compared. With the exception of bombesin receptors (BBR) that are absent from nematodes, a similar gene complement was found. In arthropods, rhodopsin GPCR evolution is characterized by species-specific gene duplications and deletions and in nematodes by gene expansions in species with a free-living stage and gene deletions in representatives of obligate parasitic taxa. Based upon variation in GPCR gene number and potentially divergent functions within phyla we hypothesize that life style and feeding diversity practiced by nematodes and arthropods was one factor that contributed to rhodopsin GPCR gene evolution. Understanding how the regulation of food intake has evolved in invertebrates will contribute to the development of novel drugs to control nematodes and arthropods and the pests and diseases that use them as vectors. PMID:23264768

  19. Habitat Heterogeneity Affects Plant and Arthropod Species Diversity and Turnover in Traditional Cornfields.

    Science.gov (United States)

    Martínez, Eliana; Rös, Matthias; Bonilla, María Argenis; Dirzo, Rodolfo

    2015-01-01

    The expansion of the agricultural frontier by the clearing of remnant forests has led to human-dominated landscape mosaics. Previous studies have evaluated the effect of these landscape mosaics on arthropod diversity at local spatial scales in temperate and tropical regions, but little is known about fragmentation effects in crop systems, such as the complex tropical traditional crop systems that maintain a high diversity of weeds and arthropods in low-Andean regions. To understand the factors that influence patterns of diversity in human-dominated landscapes, we investigate the effect of land use types on plant and arthropod diversity in traditionally managed cornfields, via surveys of plants and arthropods in twelve traditional cornfields in the Colombian Andes. We estimated alpha and beta diversity to analyze changes in diversity related to land uses within a radius of 100 m to 1 km around each cornfield. We observed that forests influenced alpha diversity of plants, but not of arthropods. Agricultural lands had a positive relationship with plants and herbivores, but a negative relationship with predators. Pastures positively influenced the diversity of plants and arthropods. In addition, forest cover seemed to influence changes in plant species composition and species turnover of herbivore communities among cornfields. The dominant plant species varied among fields, resulting in high differentiation of plant communities. Predator communities also exhibited high turnover among cornfields, but differences in composition arose mainly among rare species. The crop system evaluated in this study represents a widespread situation in the tropics, therefore, our results can be of broad significance. Our findings suggest that traditional agriculture may not homogenize biological communities, but instead could maintain the regional pool of species through high beta diversity. PMID:26197473

  20. Habitat Heterogeneity Affects Plant and Arthropod Species Diversity and Turnover in Traditional Cornfields.

    Directory of Open Access Journals (Sweden)

    Eliana Martínez

    Full Text Available The expansion of the agricultural frontier by the clearing of remnant forests has led to human-dominated landscape mosaics. Previous studies have evaluated the effect of these landscape mosaics on arthropod diversity at local spatial scales in temperate and tropical regions, but little is known about fragmentation effects in crop systems, such as the complex tropical traditional crop systems that maintain a high diversity of weeds and arthropods in low-Andean regions. To understand the factors that influence patterns of diversity in human-dominated landscapes, we investigate the effect of land use types on plant and arthropod diversity in traditionally managed cornfields, via surveys of plants and arthropods in twelve traditional cornfields in the Colombian Andes. We estimated alpha and beta diversity to analyze changes in diversity related to land uses within a radius of 100 m to 1 km around each cornfield. We observed that forests influenced alpha diversity of plants, but not of arthropods. Agricultural lands had a positive relationship with plants and herbivores, but a negative relationship with predators. Pastures positively influenced the diversity of plants and arthropods. In addition, forest cover seemed to influence changes in plant species composition and species turnover of herbivore communities among cornfields. The dominant plant species varied among fields, resulting in high differentiation of plant communities. Predator communities also exhibited high turnover among cornfields, but differences in composition arose mainly among rare species. The crop system evaluated in this study represents a widespread situation in the tropics, therefore, our results can be of broad significance. Our findings suggest that traditional agriculture may not homogenize biological communities, but instead could maintain the regional pool of species through high beta diversity.

  1. Spatial distribution and internal metal concentrations of terrestrial arthropods in a moderately contaminated lowland floodplain along the Rhine River

    Energy Technology Data Exchange (ETDEWEB)

    Schipper, Aafke M. [Department of Environmental Science, Institute for Wetland and Water Research, Radboud University Nijmegen, P.O. Box 9010, 6500 GL Nijmegen (Netherlands)], E-mail: a.schipper@science.ru.nl; Wijnhoven, Sander [Centre for Sustainable Management of Resources, Institute for Science, Innovation and Society, Radboud University Nijmegen, P.O. Box 9010, 6500 GL Nijmegen (Netherlands); Netherlands Institute of Ecology, Centre for Estuarine and Marine Ecology, Monitor Taskforce, P.O. Box 140, 4400 AC Yerseke (Netherlands); Leuven, Rob S.E.W.; Ragas, Ad M.J.; Jan Hendriks, A. [Department of Environmental Science, Institute for Wetland and Water Research, Radboud University Nijmegen, P.O. Box 9010, 6500 GL Nijmegen (Netherlands)

    2008-01-15

    Soil metal concentrations, inundation characteristics and abundances of 14 arthropod taxa were investigated in a moderately contaminated lowland floodplain along the Rhine River and compared to the hinterland. Internal metal concentrations were determined for the orders of Coleoptera (beetles) and Araneida (spiders) and were related to soil concentrations. The floodplain was characterized by larger arthropod abundance than the hinterland, in spite of recurrent inundations and higher soil metal concentrations. Most arthropod taxa showed increasing abundance with decreasing distance to the river channel and increasing average inundation duration. For Cd, Cu, Pb and Zn, significant relations were found between arthropod concentrations and concentrations in soil. Significant relations were few but positive, indicating that increasing soil concentrations result in increasing body burdens in arthropods. For arthropod-eating vertebrates, these results might imply that larger prey availability in the floodplain coincides with higher metal concentrations in prey, possibly leading to increased exposure to metal contamination. - Recurrent floodplain inundations affect terrestrial arthropod numbers and metal contamination levels.

  2. The first myriapod genome sequence reveals conservative arthropod gene content and genome organisation in the centipede Strigamia maritima

    NARCIS (Netherlands)

    Chipman, Ariel D; Ferrier, David E K; Brena, Carlo; Qu, Jiaxin; Hughes, Daniel S T; Schröder, Reinhard; Torres-Oliva, Montserrat; Znassi, Nadia; Jiang, Huaiyang; Almeida, Francisca C; Alonso, Claudio R; Apostolou, Zivkos; Aqrawi, Peshtewani; Arthur, Wallace; Barna, Jennifer C J; Blankenburg, Kerstin P; Brites, Daniela; Capella-Gutiérrez, Salvador; Coyle, Marcus; Dearden, Peter K; Du Pasquier, Louis; Duncan, Elizabeth J; Ebert, Dieter; Eibner, Cornelius; Erikson, Galina; Evans, Peter D; Extavour, Cassandra G; Francisco, Liezl; Gabaldón, Toni; Gillis, William J; Goodwin-Horn, Elizabeth A; Green, Jack E; Griffiths-Jones, Sam; Grimmelikhuijzen, Cornelis J P; Gubbala, Sai; Guigó, Roderic; Han, Yi; Hauser, Frank; Havlak, Paul; Hayden, Luke; Helbing, Sophie; Holder, Michael; Hui, Jerome H L; Hunn, Julia P; Hunnekuhl, Vera S; Jackson, LaRonda; Javaid, Mehwish; Jhangiani, Shalini N; Jiggins, Francis M; Jones, Tamsin E; Kaiser, Tobias S; Kalra, Divya; Kenny, Nathan J; Korchina, Viktoriya; Kovar, Christie L; Kraus, F Bernhard; Lapraz, François; Lee, Sandra L; Lv, Jie; Mandapat, Christigale; Manning, Gerard; Mariotti, Marco; Mata, Robert; Mathew, Tittu; Neumann, Tobias; Newsham, Irene; Ngo, Dinh N; Ninova, Maria; Okwuonu, Geoffrey; Ongeri, Fiona; Palmer, William J; Patil, Shobha; Patraquim, Pedro; Pham, Christopher; Pu, Ling-Ling; Putman, Nicholas H; Rabouille, Catherine; Ramos, Olivia Mendivil; Rhodes, Adelaide C; Robertson, Helen E; Robertson, Hugh M; Ronshaugen, Matthew; Rozas, Julio; Saada, Nehad; Sánchez-Gracia, Alejandro; Scherer, Steven E; Schurko, Andrew M; Siggens, Kenneth W; Simmons, DeNard; Stief, Anna; Stolle, Eckart; Telford, Maximilian J; Tessmar-Raible, Kristin; Thornton, Rebecca; van der Zee, Maurijn; von Haeseler, Arndt; Williams, James M; Willis, Judith H; Wu, Yuanqing; Zou, Xiaoyan; Lawson, Daniel; Muzny, Donna M; Worley, Kim C; Gibbs, Richard A; Akam, Michael; Richards, Stephen

    2014-01-01

    Myriapods (e.g., centipedes and millipedes) display a simple homonomous body plan relative to other arthropods. All members of the class are terrestrial, but they attained terrestriality independently of insects. Myriapoda is the only arthropod class not represented by a sequenced genome. We present

  3. The Multiple Impacts of Tropical Forest Fragmentation on Arthropod Biodiversity and on their Patterns of Interactions with Host Plants

    Science.gov (United States)

    Benítez-Malvido, Julieta; Dáttilo, Wesley; Martínez-Falcón, Ana Paola; Durán-Barrón, César; Valenzuela, Jorge; López, Sara; Lombera, Rafael

    2016-01-01

    Tropical rain forest fragmentation affects biotic interactions in distinct ways. Little is known, however, about how fragmentation affects animal trophic guilds and their patterns of interactions with host plants. In this study, we analyzed changes in biotic interactions in forest fragments by using a multitrophic approach. For this, we classified arthropods associated with Heliconia aurantiaca herbs into broad trophic guilds (omnivores, herbivores and predators) and assessed the topological structure of intrapopulation plant-arthropod networks in fragments and continuous forests. Habitat type influenced arthropod species abundance, diversity and composition with greater abundance in fragments but greater diversity in continuous forest. According to trophic guilds, coleopteran herbivores were more abundant in continuous forest and overall omnivores in fragments. Continuous forest showed a greater diversity of interactions than fragments. Only in fragments, however, did the arthropod community associated with H aurantiaca show a nested structure, suggesting novel and/or opportunistic host-arthropod associations. Plants, omnivores and predators contributed more to nestedness than herbivores. Therefore, Heliconia-arthropod network properties do not appear to be maintained in fragments mainly caused by the decrease of herbivores. Our study contributes to the understanding of the impact of fragmentation on the structure and dynamics of multitrophic arthropod communities associated with a particular plant species of the highly biodiverse tropical forests. Nevertheless, further replication of study sites is needed to strengthen the conclusion that forest fragmentation negatively affects arthropod assemblages. PMID:26731271

  4. The Multiple Impacts of Tropical Forest Fragmentation on Arthropod Biodiversity and on their Patterns of Interactions with Host Plants.

    Directory of Open Access Journals (Sweden)

    Julieta Benítez-Malvido

    Full Text Available Tropical rain forest fragmentation affects biotic interactions in distinct ways. Little is known, however, about how fragmentation affects animal trophic guilds and their patterns of interactions with host plants. In this study, we analyzed changes in biotic interactions in forest fragments by using a multitrophic approach. For this, we classified arthropods associated with Heliconia aurantiaca herbs into broad trophic guilds (omnivores, herbivores and predators and assessed the topological structure of intrapopulation plant-arthropod networks in fragments and continuous forests. Habitat type influenced arthropod species abundance, diversity and composition with greater abundance in fragments but greater diversity in continuous forest. According to trophic guilds, coleopteran herbivores were more abundant in continuous forest and overall omnivores in fragments. Continuous forest showed a greater diversity of interactions than fragments. Only in fragments, however, did the arthropod community associated with H aurantiaca show a nested structure, suggesting novel and/or opportunistic host-arthropod associations. Plants, omnivores and predators contributed more to nestedness than herbivores. Therefore, Heliconia-arthropod network properties do not appear to be maintained in fragments mainly caused by the decrease of herbivores. Our study contributes to the understanding of the impact of fragmentation on the structure and dynamics of multitrophic arthropod communities associated with a particular plant species of the highly biodiverse tropical forests. Nevertheless, further replication of study sites is needed to strengthen the conclusion that forest fragmentation negatively affects arthropod assemblages.

  5. The Multiple Impacts of Tropical Forest Fragmentation on Arthropod Biodiversity and on their Patterns of Interactions with Host Plants.

    Science.gov (United States)

    Benítez-Malvido, Julieta; Dáttilo, Wesley; Martínez-Falcón, Ana Paola; Durán-Barrón, César; Valenzuela, Jorge; López, Sara; Lombera, Rafael

    2016-01-01

    Tropical rain forest fragmentation affects biotic interactions in distinct ways. Little is known, however, about how fragmentation affects animal trophic guilds and their patterns of interactions with host plants. In this study, we analyzed changes in biotic interactions in forest fragments by using a multitrophic approach. For this, we classified arthropods associated with Heliconia aurantiaca herbs into broad trophic guilds (omnivores, herbivores and predators) and assessed the topological structure of intrapopulation plant-arthropod networks in fragments and continuous forests. Habitat type influenced arthropod species abundance, diversity and composition with greater abundance in fragments but greater diversity in continuous forest. According to trophic guilds, coleopteran herbivores were more abundant in continuous forest and overall omnivores in fragments. Continuous forest showed a greater diversity of interactions than fragments. Only in fragments, however, did the arthropod community associated with H aurantiaca show a nested structure, suggesting novel and/or opportunistic host-arthropod associations. Plants, omnivores and predators contributed more to nestedness than herbivores. Therefore, Heliconia-arthropod network properties do not appear to be maintained in fragments mainly caused by the decrease of herbivores. Our study contributes to the understanding of the impact of fragmentation on the structure and dynamics of multitrophic arthropod communities associated with a particular plant species of the highly biodiverse tropical forests. Nevertheless, further replication of study sites is needed to strengthen the conclusion that forest fragmentation negatively affects arthropod assemblages.

  6. Recommendations for the design of laboratory studies on non-target arthropods for risk assessment of genetically engineered plants

    Science.gov (United States)

    This paper provides recommendations on experimental design for early-tier laboratory studies used in the risk assessment process to evaluate potential adverse impacts of arthropod-resistant genetically-engineered plants on non-target arthropods. While we rely heavily on the currently used proteins f...

  7. Deriving criteria to select arthropod species for laboratory tests to assess the ecological risks from cultivating transgenic crops

    Science.gov (United States)

    Arthropods form a major part of the biodiversity in agricultural landscapes. Many species are valued because they provide ecosystem services, including biological control, pollination, and decomposition, or because they are valued for cultural or economic reasons. Some arthropods reduce crop yield a...

  8. The Multiple Impacts of Tropical Forest Fragmentation on Arthropod Biodiversity and on their Patterns of Interactions with Host Plants.

    Science.gov (United States)

    Benítez-Malvido, Julieta; Dáttilo, Wesley; Martínez-Falcón, Ana Paola; Durán-Barrón, César; Valenzuela, Jorge; López, Sara; Lombera, Rafael

    2016-01-01

    Tropical rain forest fragmentation affects biotic interactions in distinct ways. Little is known, however, about how fragmentation affects animal trophic guilds and their patterns of interactions with host plants. In this study, we analyzed changes in biotic interactions in forest fragments by using a multitrophic approach. For this, we classified arthropods associated with Heliconia aurantiaca herbs into broad trophic guilds (omnivores, herbivores and predators) and assessed the topological structure of intrapopulation plant-arthropod networks in fragments and continuous forests. Habitat type influenced arthropod species abundance, diversity and composition with greater abundance in fragments but greater diversity in continuous forest. According to trophic guilds, coleopteran herbivores were more abundant in continuous forest and overall omnivores in fragments. Continuous forest showed a greater diversity of interactions than fragments. Only in fragments, however, did the arthropod community associated with H aurantiaca show a nested structure, suggesting novel and/or opportunistic host-arthropod associations. Plants, omnivores and predators contributed more to nestedness than herbivores. Therefore, Heliconia-arthropod network properties do not appear to be maintained in fragments mainly caused by the decrease of herbivores. Our study contributes to the understanding of the impact of fragmentation on the structure and dynamics of multitrophic arthropod communities associated with a particular plant species of the highly biodiverse tropical forests. Nevertheless, further replication of study sites is needed to strengthen the conclusion that forest fragmentation negatively affects arthropod assemblages. PMID:26731271

  9. Mosquito gut antiparasitic and antiviral immunity.

    Science.gov (United States)

    Saraiva, Raúl G; Kang, Seokyoung; Simões, Maria L; Angleró-Rodríguez, Yesseinia I; Dimopoulos, George

    2016-11-01

    Mosquitoes are responsible for the transmission of diseases with a serious impact on global human health, such as malaria and dengue. All mosquito-transmitted pathogens complete part of their life cycle in the insect gut, where they are exposed to mosquito-encoded barriers and active factors that can limit their development. Here we present the current understanding of mosquito gut immunity against malaria parasites, filarial worms, and viruses such as dengue, Chikungunya, and West Nile. The most recently proposed immune mediators involved in intestinal defenses are discussed, as well as the synergies identified between the recognition of gut microbiota and the mounting of the immune response. PMID:26827888

  10. Background internal dose rates of earthworm and arthropod species in the forests of Aomori, Japan

    International Nuclear Information System (INIS)

    In this study, we measured the concentrations of several natural radionuclides in samples of one earthworm species and 11 arthropod species collected from four coniferous forests in Rokkasho, Aomori Prefecture, Japan, and we assessed the background internal radiation dose rate for each species. Dose rates were calculated by using the radionuclide concentrations in the samples and dose conversion coefficients obtained from the literature. The mean internal dose rate in the earthworm species was 0.28 μGy h-1, and the mean internal dose rates in the arthropod species ranged between 0.036 and 0.69 μGy h-1. (author)

  11. Review of available evidence regarding the vulnerability of off-crop non-target arthropod communities in comparison to in-crop non-target arthropod communities

    OpenAIRE

    Lange, de, E.C.M.; Lahr, J.; Brouwer, J.H.D.; Faber, J. H.

    2012-01-01

    EFSA is revising and updating the Ecotoxicology Guidance Document on Terrestrial Risk Assessment of Pesticides (SANCO/10329/2002). For this purpose an overview of available scientific information on several topics is needed. The aim of the current literature survey was to collect and summarize the published scientific literature on (1) the composition of non-target arthropod species that occur in and outside crops, (2) their vulnerability to pesticides and (3) their potential to recover from ...

  12. [Effects of plant viruses on vector and non-vector herbivorous arthropods and their natural enemies: a mini review].

    Science.gov (United States)

    He, Xiao-Chan; Xu, Hong-Xing; Zhou, Xiao-Jun; Zheng, Xu-Song; Sun, Yu-Jian; Yang, Ya-Jun; Tian, Jun-Ce; Lü, Zhong-Xian

    2014-05-01

    Plant viruses transmitted by arthropods, as an important biotic factor, may not only directly affect the yield and quality of host plants, and development, physiological characteristics and ecological performances of their vector arthropods, but also directly or indirectly affect the non-vector herbivorous arthropods and their natural enemies in the same ecosystem, thereby causing influences to the whole agro-ecosystem. This paper reviewed the progress on the effects of plant viruses on herbivorous arthropods, including vector and non-vector, and their natural enemies, and on their ecological mechanisms to provide a reference for optimizing the management of vector and non-vector arthropod populations and sustainable control of plant viruses in agro-ecosystem.

  13. The cultivation of Bt corn producing Cry1Ac toxins does not adversely affect non-target arthropods.

    Science.gov (United States)

    Guo, Yanyan; Feng, Yanjie; Ge, Yang; Tetreau, Guillaume; Chen, Xiaowen; Dong, Xuehui; Shi, Wangpeng

    2014-01-01

    Transgenic corn producing Cry1Ac toxins from Bacillus thuringiensis (Bt) provides effective control of Asian corn borer, Ostrinia furnacalis (Guenée), and thus reduces insecticide applications. However, whether Bt corn exerts undesirable effects on non-target arthropods (NTAs) is still controversial. We conducted a 2-yr study in Shangzhuang Agricultural Experiment Station to assess the potential impact of Bt corn on field population density, biodiversity, community composition and structure of NTAs. On each sampling date, the total abundance, Shannon's diversity index, Pielou's evenness index and Simpson's diversity index were not significantly affected by Bt corn as compared to non-Bt corn. The "sampling dates" had a significant effect on these indices, but no clear tendencies related to "Bt corn" or "sampling dates X corn variety" interaction were recorded. Principal response curve analysis of variance indicated that Bt corn did not alter the distribution of NTAs communities. Bray-Curtis dissimilarity and distance analysis showed that Cry1Ac toxin exposure did not increase community dissimilarities between Bt and non-Bt corn plots and that the evolution of non-target arthropod community was similar on the two corn varieties. The cultivation of Bt corn failed to show any detrimental evidence on the density of non-target herbivores, predators and parasitoids. The composition of herbivores, predators and parasitoids was identical in Bt and non-Bt corn plots. Taken together, results from the present work support that Bt corn producing Cry1Ac toxins does not adversely affect NTAs. PMID:25437213

  14. The cultivation of Bt corn producing Cry1Ac toxins does not adversely affect non-target arthropods.

    Directory of Open Access Journals (Sweden)

    Yanyan Guo

    Full Text Available Transgenic corn producing Cry1Ac toxins from Bacillus thuringiensis (Bt provides effective control of Asian corn borer, Ostrinia furnacalis (Guenée, and thus reduces insecticide applications. However, whether Bt corn exerts undesirable effects on non-target arthropods (NTAs is still controversial. We conducted a 2-yr study in Shangzhuang Agricultural Experiment Station to assess the potential impact of Bt corn on field population density, biodiversity, community composition and structure of NTAs. On each sampling date, the total abundance, Shannon's diversity index, Pielou's evenness index and Simpson's diversity index were not significantly affected by Bt corn as compared to non-Bt corn. The "sampling dates" had a significant effect on these indices, but no clear tendencies related to "Bt corn" or "sampling dates X corn variety" interaction were recorded. Principal response curve analysis of variance indicated that Bt corn did not alter the distribution of NTAs communities. Bray-Curtis dissimilarity and distance analysis showed that Cry1Ac toxin exposure did not increase community dissimilarities between Bt and non-Bt corn plots and that the evolution of non-target arthropod community was similar on the two corn varieties. The cultivation of Bt corn failed to show any detrimental evidence on the density of non-target herbivores, predators and parasitoids. The composition of herbivores, predators and parasitoids was identical in Bt and non-Bt corn plots. Taken together, results from the present work support that Bt corn producing Cry1Ac toxins does not adversely affect NTAs.

  15. The SARS-coronavirus papain-like protease: structure, function and inhibition by designed antiviral compounds.

    Science.gov (United States)

    Báez-Santos, Yahira M; St John, Sarah E; Mesecar, Andrew D

    2015-03-01

    Over 10 years have passed since the deadly human coronavirus that causes severe acute respiratory syndrome (SARS-CoV) emerged from the Guangdong Province of China. Despite the fact that the SARS-CoV pandemic infected over 8500 individuals, claimed over 800 lives and cost billions of dollars in economic loss worldwide, there still are no clinically approved antiviral drugs, vaccines or monoclonal antibody therapies to treat SARS-CoV infections. The recent emergence of the deadly human coronavirus that causes Middle East respiratory syndrome (MERS-CoV) is a sobering reminder that new and deadly coronaviruses can emerge at any time with the potential to become pandemics. Therefore, the continued development of therapeutic and prophylactic countermeasures to potentially deadly coronaviruses is warranted. The coronaviral proteases, papain-like protease (PLpro) and 3C-like protease (3CLpro), are attractive antiviral drug targets because they are essential for coronaviral replication. Although the primary function of PLpro and 3CLpro are to process the viral polyprotein in a coordinated manner, PLpro has the additional function of stripping ubiquitin and ISG15 from host-cell proteins to aid coronaviruses in their evasion of the host innate immune responses. Therefore, targeting PLpro with antiviral drugs may have an advantage in not only inhibiting viral replication but also inhibiting the dysregulation of signaling cascades in infected cells that may lead to cell death in surrounding, uninfected cells. This review provides an up-to-date discussion on the SARS-CoV papain-like protease including a brief overview of the SARS-CoV genome and replication followed by a more in-depth discussion on the structure and catalytic mechanism of SARS-CoV PLpro, the multiple cellular functions of SARS-CoV PLpro, the inhibition of SARS-CoV PLpro by small molecule inhibitors, and the prospect of inhibiting papain-like protease from other coronaviruses. This paper forms part of a series of

  16. Emerging complexity and new roles for the RIG-I-like receptors in innate antiviral immunity

    Institute of Scientific and Technical Information of China (English)

    John; S.Errett; Michael; Gale; Jr.

    2015-01-01

    Innate immunity is critical for the control of virus infection and operates to restrict viral susceptibility and direct antiviral immunity for protection from acute or chronic viral-associated diseases including cancer. RIG-I like receptors(RLRs) are cytosolic RNA helicases that function as pathogen recognition receptors to detect RNA pathogen associated molecular patterns(PAMPs) of virus infection. The RLRs include RIG-I, MDA5, and LGP2. They function to recognize and bind to PAMP motifs within viral RNA in a process that directs the RLR to trigger downstream signaling cascades that induce innate immunity that controls viral replication and spread. Products of RLR signaling also serve to modulate the adaptive immune response to infection. Recent studies have additionally connected RLRs to signaling cascades that impart inflammatory and apoptotic responses to virus infection. Viral evasion of RLR signaling supports viral outgrowth and pathogenesis, including the onset of viral-associated cancer.

  17. Maternal Antibiotic Treatment Impacts Development of the Neonatal Intestinal Microbiome and Antiviral Immunity.

    Science.gov (United States)

    Gonzalez-Perez, Gabriela; Hicks, Allison L; Tekieli, Tessa M; Radens, Caleb M; Williams, Brent L; Lamousé-Smith, Esi S N

    2016-05-01

    Microbial colonization of the infant gastrointestinal tract (GIT) begins at birth, is shaped by the maternal microbiota, and is profoundly altered by antibiotic treatment. Antibiotic treatment of mothers during pregnancy influences colonization of the GIT microbiota of their infants. The role of the GIT microbiota in regulating adaptive immune function against systemic viral infections during infancy remains undefined. We used a mouse model of perinatal antibiotic exposure to examine the effect of GIT microbial dysbiosis on infant CD8(+) T cell-mediated antiviral immunity. Maternal antibiotic treatment/treated (MAT) during pregnancy and lactation resulted in profound alterations in the composition of the GIT microbiota in mothers and infants. Streptococcus spp. dominated the GIT microbiota of MAT mothers, whereas Enterococcus faecalis predominated within the MAT infant GIT. MAT infant mice subsequently exhibited increased and accelerated mortality following vaccinia virus infection. Ag-specific IFN-γ-producing CD8(+) T cells were reduced in sublethally infected MAT infant mice. MAT CD8(+) T cells from uninfected infant mice also demonstrated a reduced capacity to sustain IFN-γ production following in vitro activation. We additionally determined that control infant mice became more susceptible to infection if they were born in an animal facility using stricter standards of hygiene. These data indicate that undisturbed colonization and progression of the GIT microbiota during infancy are necessary to promote robust adaptive antiviral immune responses. PMID:27036912

  18. Beyond TLR Signaling—The Role of SARM in Antiviral Immune Defense, Apoptosis & Development.

    Science.gov (United States)

    Panneerselvam, Porkodi; Ding, Jeak Ling

    2015-01-01

    SARM (Sterile alpha and armadillo motif-containing protein) is the recently identified TIR domain-containing cytosolic protein. Classified as a member of the TLR adaptor family, the multiple locations and functions of SARM (sometimes playing opposing roles), provoke an enigma on its biology. Although originally assumed to be a member of the TLR adaptor family (functioning as a negative regulator of TLR signaling pathway), latest findings indicate that SARM regulates signaling differently from other TLR adaptor proteins. Recent studies have highlighted the significant functional role of SARM in mediating apoptosis and antiviral innate immune response. In this review, we provide an update on the evolutionary conservation, spatial distribution, and regulated expression of SARM to highlight its diverse functional roles. The review will summarize findings on the known interacting partners of SARM and provide analogy on how they add new dimensions to the current understanding on the multifaceted roles of SARM in antiviral activities and apoptotic functions. In addition, we provide a future perspective on the roles of SARM in differentiation and development, with substantial emphasis on the molecular insights to its mechanisms of action. PMID:26268046

  19. Evasion of antiviral innate immunity by Theiler's virus L* protein through direct inhibition of RNase L.

    Directory of Open Access Journals (Sweden)

    Frédéric Sorgeloos

    Full Text Available Theiler's virus is a neurotropic picornavirus responsible for chronic infections of the central nervous system. The establishment of a persistent infection and the subsequent demyelinating disease triggered by the virus depend on the expression of L*, a viral accessory protein encoded by an alternative open reading frame of the virus. We discovered that L* potently inhibits the interferon-inducible OAS/RNase L pathway. The antagonism of RNase L by L* was particularly prominent in macrophages where baseline oligoadenylate synthetase (OAS and RNase L expression levels are elevated, but was detectable in fibroblasts after IFN pretreatment. L* mutations significantly affected Theiler's virus replication in primary macrophages derived from wild-type but not from RNase L-deficient mice. L* counteracted the OAS/RNase L pathway through direct interaction with the ankyrin domain of RNase L, resulting in the inhibition of this enzyme. Interestingly, RNase L inhibition was species-specific as Theiler's virus L* protein blocked murine RNase L but not human RNase L or RNase L of other mammals or birds. Direct RNase L inhibition by L* and species specificity were confirmed in an in vitro assay performed with purified proteins. These results demonstrate a novel viral mechanism to elude the antiviral OAS/RNase L pathway. By targeting the effector enzyme of this antiviral pathway, L* potently inhibits RNase L, underscoring the importance of this enzyme in innate immunity against Theiler's virus.

  20. Deep sequencing analysis of HBV genotype shift and correlation with antiviral efficiency during adefovir dipivoxil therapy.

    Directory of Open Access Journals (Sweden)

    Yuwei Wang

    Full Text Available Viral genotype shift in chronic hepatitis B (CHB patients during antiviral therapy has been reported, but the underlying mechanism remains elusive.38 CHB patients treated with ADV for one year were selected for studying genotype shift by both deep sequencing and Sanger sequencing method.Sanger sequencing method found that 7.9% patients showed mixed genotype before ADV therapy. In contrast, all 38 patients showed mixed genotype before ADV treatment by deep sequencing. 95.5% mixed genotype rate was also obtained from additional 200 treatment-naïve CHB patients. Of the 13 patients with genotype shift, the fraction of the minor genotype in 5 patients (38% increased gradually during the course of ADV treatment. Furthermore, responses to ADV and HBeAg seroconversion were associated with the high rate of genotype shift, suggesting drug and immune pressure may be key factors to induce genotype shift. Interestingly, patients with genotype C had a significantly higher rate of genotype shift than genotype B. In genotype shift group, ADV treatment induced a marked enhancement of genotype B ratio accompanied by a reduction of genotype C ratio, suggesting genotype C may be more sensitive to ADV than genotype B. Moreover, patients with dominant genotype C may have a better therapeutic effect. Finally, genotype shifts was correlated with clinical improvement in terms of ALT.Our findings provided a rational explanation for genotype shift among ADV-treated CHB patients. The genotype and genotype shift might be associated with antiviral efficiency.